Transcript
Innovation & New Technology Final Project Report SynthoTrax I-Seal Robot August 2013 A consolidated summary report by Sam Wilson, Innovation Project Manager on behalf of Angus McIntosh, Innovation & New Technology Manager
Key Contributors: Sam Wilson: SGN David McLeod: SGN Angus McIntosh: SGN Simon Langdale: Synthotec Ltd Wez Little: Synthotec Ltd Mark Tindley: Synthotech Ltd
“The information in this report has been provided by SGN. While the report has been prepared in good faith, no representation, warranty, assurance or undertaking (express or implied) is or will be made, and no responsibility or liability is or will be accepted by SGN or any of SGN’s subsidiaries in relation to the adequacy, accuracy, completeness or reasonableness of this report. All and any such responsibility and liability is expressly disclaimed.”
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Document Control
Version
Status
Date
Author(s)
Summary of Changes
V1.0
Draft
15/05/2015
Synthotech Ltd
Initial draft
V1.1
Draft
05/06/2015
Sam Wilson / David Mcleod
Second draft
V1.2
Final
28/06/2015
Angus Mcintosh
Final Approval
Reviewers Name
Job Title
Email
David McLeod
Innovation Delivery Manager
[email protected]
Sam Wilson
Project Manager – Innovation
[email protected]
Angus McIntosh
Innovation & New Technology Manager
[email protected]
Management Approval
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Name
Role
Angus McIntosh
Innovation & New Technology Manager
Signature
Contents
Key Contributors .......................................................................................... Error! Bookmark not defined. Reviewers .............................................................................................................................................. 3 Management Approval .......................................................................................................................... 3 1 Introduction ........................................................................................................................................ 5 1.1 Executive Summary ..................................................................................................................................... 5 1.2 Summary of Recommendations .................................................................................................................. 6 1.3 Project Background ..................................................................................................................................... 7 1.4 Network Innovation Funding ....................................................................................................................... 7 1.5 Investment Options ..................................................................................................................................... 8 1.6 SynthoTrax I-Seal Robot .............................................................................................................................. 8 1.7 Project Objectives ...................................................................................................................................... 11 2 Alpha Testing – Preliminary Works Prior to Field Trial ........................................................................ 12 2.1 Access Fitting ............................................................................................................................................. 12 2.2 Access System ............................................................................................................................................ 16 17 2.3 In-pipe Robotics Platform .......................................................................................................................... 19 2.4 Sealant Application System ....................................................................................................................... 32 2.5 In-pipe CCTV Inspection............................................................................................................................. 36 2.6 External Support Systems .......................................................................................................................... 41 2.7 Synthotech ISP ........................................................................................................................................... 42 2.8 Report Conclusion and Recommendations ............................................................................................... 58 Appendix A - Glossary of Terms ............................................................................................................ 65 Appendix B - Development Specification .............................................................................................. 66 Appendix C - Development of methodology for SynthoTrax ISP ............................................................. 70 Appendix D - Original SynthoTrax ISP Proposal ..................................................................................... 73 Appendix E - I-Seal ............................................................................................................................... 81 Appendix F - CCTV Inspection Camera Comparison................................................................................ 82 Appendix G - SynthoTrax ...................................................................................................................... 85 Appendix H - Relevant Standards .......................................................................................................... 86 Appendix I - Work Completed............................................................................................................... 89 Appendix J - References ....................................................................................................................... 90 Appendix K - Bond and Bolt case study ................................................................................................. 95
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Final Project Report
1 Introduction 1.1 Executive Summary This feasibility report evaluates the possibility of developing a robotic system that can remediate potentially leaking gas joints, under live conditions, up to a distance of 200 metres from a single live access point. As part of SGNs drive to maintain safe gas transportation while meeting the 30/30 program and operating in the OFGEM RIIO period of 2013 to 2021, SGN are focused on maintaining their larger diameter gas network in both Southern and Scotland Networks. As part of this process, they aim to reduce customer dissatisfaction, minimise cost and maximise available resources to provide long-term network integrity. As part of OFGEM RIIO Tier 3, 18” to 48” metallic mains need to be assessed against risk and costly replacement. It has been identified through the OFGEM review that larger diameter metallic gas mains are less likely to fail through fracture and more prone to failure through leaks within the existing joints. Synthotech Ltd have extensive experience of in-pipe CCTV camera technologies, and have developed the SynthoTrax robotic platform. This system has successfully completed over 35 working jobs on live gas mains throughout the UK including three surveys for SGN. The purpose of this feasibility report is to investigate the potential to extend the capability of the Synthotech SynthoTrax architecture to enable remote internal joint sealing of gas pipes that: 1. 2. 3. 4.
Are between 18” and 48” diameter metallic mains Can operate at low pressure (≤75mbar) and medium pressure (>75mbar, ≤ 2bar). Can remediate up to 400m of main from one excavation Can drill (if required), inject and seal gas main joints from inside the main under live conditions.
The feasibility has looked into the individual requirements for; 1. 2. 3. 4. 5. 6.
Access Fitting Access System In-pipe robotic platform Sealant Application System In-pipe CCTV External Support Systems
The feasibility highlights a system called CISBOT developed in North America; however, details are limited on this product, and therefore not fully evaluated. The feasibility also highlights how the SynthoTrax architecture can be converted into a joint remediation system with three possible variants. 1. Spray system 2. Point Contact System 3. Drill and inject System. These options have increasing cost and complexity; however, the development process is generic across the three solutions. Therefore, the project has the potential to run as per its original proposal, with completion by December 31st 2013.
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Final Project Report Potential SynthoTrax ISP methodologies Spray System
Point Contact
Drill & Inject
Access Fitting
Already Capable
Already Capable
Already Capable
Access System
Already Capable
Some Development
Some Development
In-pipe Platform
Already Capable
High Development
High Development
Some Development
High Development
High Development
Already Capable
Already Capable
Already Capable
Some Development
Medium Development
Medium Development
Sealant application system In-pipe CCTV External Support System
Where it has been defined as already capable, some programming and modification may be required to ensure compatibility additional developments in other sub-systems.
In conclusion, the development of a robotic sealant application system based on the SynthoTrax platform for live access through 160mm diameter access holes (ALH System Three Valve) is possible, with a low risk of failure and achievable within the predicted timescale and budget. Further work could look at combining the SynthoTrax platform with an acoustic leakage detection device currently under various third party developments. The intended outputs from the system are to; 1. Highlight conformance to RIIO within Tier 3 (18-48") mains. 2. Manage risk associated with leaking Tier 3 mains through joints 3. Offer improved efficiency over classical sealing methods* (Mainspray, encapsulation etc.) Another option would be to investigate the use of the Large CISBOT system developed by ULC Robotics. Information on the system was limited and as a result has not been covered fully in this report. However the information that was publicly available indicates that the system is one of the most advanced robotic solutions on the market and should be investigated further by SGN.
1.2 Summary of Recommendations Alpha Testing – Preliminary works prior to field trial 1. It is recommended that the in-pipe sub-systems are designed to gain access through a 160mm diameter hole. 2. It is recommended that SGN review the future cross project requirements of remediation and inspection work in relation to construction of permanent access points. 3. It is recommended that SGN review the diameter range of 18” and up to but not including 24” and the quarter diameter access requirements in relation to full circumferential clamps and permanent access valves. Access Systems It is recommended that the access system choice be made against the final in-pipe device, whether this is a specific or a current applicable system. The access system should minimise excavations, the preference methodology for this would be a vertical insertion system. A vertical insertion method has the additional benefit of being particularly compatible with keyhole excavation techniques. In pipe robotic platform There is currently not enough information for the feasibility to comment on the suitability of the ‘Big CISBOT’ and therefore this has been left out of the communication and recommendations. 6
Final Project Report Although the SynthoTrax system meets all of the performance requirements from this section of the report, technology developments would be required to allow a complete system to meet all of the performance requirements from every section of this report. Based solely on this section of the report the recommendation would be the use of the SynthoTrax Robotic platform. Sealant Application System No single system could meet the performance for this section of the report. There is insufficient information regarding the 'big CISBOT' to draw any conclusions or recommendations as to its applicability within the scope of this project. In order to cover the full range of outline performance specifications a development would be required. The recommended action would be to develop the SynthoTrax architecture to seal the cast joints by, either; 1. Controlled Directional Spraying of Cast Joints 2. Point contact sealant injection into the Cast Joints 3. Drilled sealant injection into the Cast Joints In pipe CCTV The recommendation here would be to use the native camera options available based upon sub-system used elsewhere within the device. Should a development activity follow this project then task specific camera systems should be implemented within the complete device.
1.3 Project Background Synthotech Limited is a modern engineering company with a proven history of design, development, manufacture, and supply services to the utilities and industrial market sector both in the UK and worldwide. They currently design and manufacture practical engineering solutions for problems that face the gas and utilities industries worldwide. They have extensive experience of in-pipe camera technologies, and have developed the SynthoTrax robotic platform, which has successfully completed over 35 working jobs on live gas mains throughout the UK, including three surveys for SGN. In 2009, Synthotech started work on an Intelligent Robotic Vehicle, which has subsequently been developed into a full vision system for 18” to 48” diameter mains operating at pressures up to 2bar. Since then they have also developed a scanning system for use with the SynthoTrax platform, allowing PE pipe to be scanned internally. They have manufactured the I-Seal System, a versatile, safe and efficient method of repairing leaking joints on gas pipe work systems. I-Seal has been used successfully by the UK gas industry since 1986. At SGN we are focused on maintaining our larger diameter gas networks both North and South. As part of this process we aim to reduce customer dissatisfaction and minimise cost, whilst providing long term integrity to our network. Moving into GD1, tier 2 and 3 mains will need to be assessed against risk and costly replacement. It has been identified through the OFGEM review that larger diameter metallic gas pipes are less likely to fail through cracks and fractures, and more likely to fail due to leaks within the existing joints.
SGN approached Synthotech to carry out an industry wide feasibility study and to investigate the potential to develop the SynthoTrax platform so that it can internally seal leaking joints on larger diameter gas mains.
1.4 Network Innovation Funding Innovation is a key element of the new RIIO (Revenue = Incentives + Innovation + Outputs) model for price controls, introduced in to the gas distribution market from 1st April 2013. One of the key innovation proposals
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Final Project Report was the introduction of both the Network Innovation Allowance (NIA) and the Network Innovation Competition (NIC) for all Network Licensees funded under the RIIO framework. The purpose of these funding mechanisms is to provide a consistent level of funding to Network Licensees to allow them to carry out research, development and demonstration of projects which at an early stage yield uncertain commercial returns. In addition, where benefits are linked to the decarbonisation of the network, it may be difficult to commercialise the respective carbon and/or environmental benefits and shareholders may be unwilling to speculatively fund such Projects. Network Innovation Allowance (NIA) – to fund smaller innovation Projects that will deliver benefits to Customers as part of a RIIO-Network Licensee’s price control settlement; or to fund the preparation of submissions to the NIC. Network Innovation Competition (NIC) – an annual competition to fund selected flagship innovative Projects that would deliver low carbon and environmental benefits to Customers.
1.5 Investment Options Option One: Do nothing
Option Two: SynthoTrax I-Seal (Delivery in 1 year)
Option Three: SynthoTrax I-Seal (Delivery in 2 years)
Option Four: Contact ULC Robotics and field trial the Large CISBOT system
1.6 SynthoTrax I-Seal Robot Synthotech and SGN have developed the following outline performance specification from the original proposal. At this stage of the feasibility, Synthotech has made some assumptions. These are documented at the end of this section of the report. A brief outline of the proposed system is depicted, and then detailed below;
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Final Project Report
SL joint Sealing System
Pipeline Access
Access Fitting
Robotic Access System
In-pipe Robotics platform
In-pipe locomation
Sealant application
Pre & post Redidiation inspection
Actuatuate to leak location
In pipe CCTV
Sealant application
Leak detection?
Figure 1 – outline performance specification flowchart.
Figure 2 – system representation
Access Fitting Pipe access standardisation where possible. For 18” to 24” Mains through a Full Circumferential Clamp and a Donkin 555 valve vertically into the main For 24” to 48” Mains through a 160mm diameter access hole (6” BSP Non Tapped) using an ALH System 3 Valve. Access into Steel, Cast Iron, Ductile Iron and Spun Iron Mains
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Final Project Report Capability to sit within a standard access chamber dimensions Pipe depths are nominally 1000mm, with depth range from 750mm to 1500mm. To be designed with a view for compatibility with future keyhole technologies. Access System Standardisation across the SynthoTrax range where possible ‘No-gas’ (leak tight) sealing system due to the high risk nature of natural gas Full installation and retrieval capability from single access point, or installation and retrieval from go and grab (access point to egress point) points Multitasking of the go and grab access points to meet the insertion distance from a single access point requirement Manufactured from appropriately reduced/non-sparking materials to meet codes of practice for gas standards where required. Running seal system with a safety factor of 2 Over pressure system with a safety factor of 1.5 Robust design for continued use Lightweight and portable for continuous connection and removal In-Pipe platform / Propulsion / Locomotion Capable of application with mains between 18" and 48" Capable of launch through standard pipeline access methodologies Not to be adversely affected by the sealant medium used for sealing the joints Maintains manoeuvrability within pipelines allowing negotiation of obstacles To have inbuilt fail safe systems To travel and function within pipelines at distances of 200m from the access point To provide the required stability for sealing (inc drilling*) operations To operate within an atmosphere of Natural Gas To be used at pressure of up to 2 bar Sealant Application Capable of application in mains between 18" and 48" Capable of launch through standard pipeline access methodologies and equipment To function within pipelines at distances of 200m from the access point To operate within an xatmosphere of Natural Gas To be used at pressure operating up to 2 bar with an over pressure of 1.5x To Seal joints effectively with/against the expected flow of gas within the main Able to seal all available joints from a single insertion Be compatible with existing approved LC9 Sealants Able to seal a leaking joint up to a test pressure of 3 bar Pre & Post remediation Inspection Standardisation where possible with existing SynthoCam CCTV systems Full circumferential vision in 18” to 48” metallic main diameter pipes Able to operate within Natural Gas Able to illuminate the full working environment Function at 200 metres from the access location Able to operate at 2 Bar external pressure To be able to survey pre and post remediation Vision not to be affected by the leakage sealant
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Final Project Report
1.7 Project Objectives The aim of this Feasibility report is to investigate the technical plausibility behind the development of a robotically based system that can remotely travel to, locate, and seal leaking joints. The system will; 1. 2. 3. 4. 5.
Be applied within metallic pipelines between 18” and 48” diameter. Seal joints of said mains (Lead yarn - Bell and socket) Operate in 'low pressure' (≤75mbar) and 'medium pressure' (>75mbar, ≤ 2bar) natural gas flows. Cover up to 400m of joints from one excavation Conduct all operations under 'live gas' conditions.
The intended outputs from the system are to include; 1. Highlight conformance to RIIO within Tier 3 (18-48") mains. 2. Manage risk associated to leaking Tier 3 mains through joints 3. Offer improved efficiency over classical sealing methods (Mainspray, encapsulation etc.)
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Final Project Report
2 Alpha Testing – Preliminary Works Prior to Field Trial 2.1 Access Fitting Aim The aim of the Access Fitting feasibility study is to identify if a suitable access fitting exists for use as part of the leakage sealant delivery system. Objectives The objectives of the access fitting feasibility study are to:
Identify what is required from an access fitting Identify what are the critical aspects of an access fitting Identify what access fitting(s) are currently available Recommend an access fitting for use or development Identify potential information required to confirm successful application
Research Undertaken The research was carried out by; Visiting Trade Stands Visiting and reviewing existing technology on sale within the UK and talking to importers and exporters of fittings worldwide Visiting pipe access fitting companies within the UK Visiting and reviewing emerging technology within the UK market Web Searches Web searches identifying any existing systems that meet the objectives. Workshop Testing Testing concepts, in particular with larger diameter pipe within a workshop environment SynthoCam™ and SynthoTrax™ Product and Data File Review Reviewing the issues and technical difficulty/ease that the current SynthoCam™ and SynthoTrax™ product range encounters within metallic pipe and fittings
Comparison of technologies For live access into large diameter metallic main (18" - 48"), there are currently access methodologies available, temporary and permanent.
Temporary Access Fittings Most work carried out within the UK gas distribution networks on large diameter pipes is carried out using temporary saddle valves that are securely connected onto the main to allow drilling and live access. Following completion of the work the access fitting allows a completion plug or flange to be fitted, and the temporary valve is then removed. The ubiquitous example of this type of valve is the WASK base set, however this set is limited to a 56mm diameter access hole. Other valves available include the Pipetech Gas Master which is also limited to 56mm, and the ALH System One base set which is limited to a 73mm diameter access hole. For larger temporary access the only system available is the ALH System Three valve, which is the industry standard in the UK. This valve allows an access hole of up to 160mm in diameter under live gas conditions. 12
Final Project Report
Permanent Access Fittings Permanent access fittings are traditionally only used when a main needs supporting due to an over drilling requirement, or where a new connection is required. The predominant methodology for providing a permanent access fitting utilises a full encirclement clamp. Connected to the Access Fittings there needs to be a permanent valve. The primary valves used in the UK are the AVK range, with WASK and Aeon also providing valves into the market. Typically, AVK 555 valves are used.
Figure 3 and 4 – AVK Encirclement clamp (L) and AVK 555 Valve (R) Access Hole For any development where there is a live access requirement, it is always preferable to have the largest access hole possible. This not only aids tool insertion but it also allows the in-pipe device to be comparable in size with the main to be remediated. However full bore access is not only costly, it is in most cases impracticable and unlikely. One of the key factors for this feasibility is to highlight the additional requirements, cost and implications of having to develop a new range of access fittings, access valves and live access drilling machines. Therefore, the final solution must be compatible with existing equipment currently approved by the GDNs (gas distribution networks) in particular equipment that they have already invested in. A requirement of the development is to work with equipment that is already proven and available. For temporary fittings and permanent fittings on pipe sizes above 24”, the standard practice is to drill a 160mm diameter hole (6” BSP Non-Tapped). On pipes sizes from 18” to 24", a full encirclement clamp would need to be fitted due to the current UK network requirement to limit drilling diameters to one quarter of the diameter of the main (only 4 ½” BSP Non Tapped for an 18” main). Temporary and permanent There are advantages to both temporary and permanent fittings Temporary fittings are able to be fitted and completed very quickly using non-tapped plugs. However, they are not reusable, and the completion fitting or 'plug' is subsequently viewed as a permanent fitting. Permanent fittings take considerably more time to assemble, and represent increased costs associated to the branch fitting and valve that will be left in situ. However, once fitted, the access fitting can be re-used multiple times during the asset life.
Figure 5 WASK nontapped plug
Temporary, Permanent and RIIO Previously under the last OFGEM regulatory period there was no advantage to permanently assembling a valve and branch fitting for access into the larger diameter mains. This is because the pipe was due to be replaced 13
Final Project Report with Polyethylene by 2032. Due to the confidence gained over the last regulatory period with larger diameter mains, and the subsequent reduction in risk associated to catastrophic failure of said pipes, a significant number or larger diameter mains have been de-risked and are now identified as non-mandatory replacement. They do not have to be replaced as long as the maintenance of the main is satisfactory. This is a key driver for this development, being able to maintain the joints over a longer period with reduced excavation. When the cost of a permanent access point in a busy street is quantified in relation to the future life and maintenance cost of the asset, then the system becomes a more favourable and viable solution when compared with repeated temporary access locations, drilling and excavations. New Innovations The Bond and Bolt System from ALH Systems in conjunction with the Synthotech SynthoTrax is currently being trialled with National Grid Gas. This allows access into large diameter gas mains using the ALH System Three valve without requiring a full circumferential excavation. The system works by excavating to the top of the main, shot blasting the surface, and bonding a slave saddle to the top of the main. The saddle is then bolted into the main using a special live gas bolt system. Once the bonding adhesive has cured (currently 24Hrs), the valve assembly is fitted followed by the drilling, access and completion using a non-tapped plug. This provides a significant reduction in excavation and re-instatement while developing a half permanent and half temporary fitting. Further review is required when more field trials have been completed.
Figure 6 – ALH bond & bolt system with an ALH system 3 valve.
Standards There are no current standards for temporary fitting valve systems. These are included with other fittings and processes such as bagging off and flow stopping. For example, the ALH Systems Three Valve has been approved via their IRIS flow stopping approval. The following standards are for the permanent fitting encirclement clamps. Gas Industry Standard LC8 Part 4 ANSI B31.8 The following standards are for the permanent fitting valve systems Gas Industry Standard V7 Part 1 BS5150 BS EN 12266 The Gas Transporters Mains Laying Manual will provide the detail working procedures for the use of such valves, encirclement clamps and processes. This would need to be combined with the latest version of D7, the working procedure for the use of CCTV equipment inside live gas mains. 14
Final Project Report Gap Analysis Currently a 160mm diameter hole cannot be drilled into 18” to 23” mains. This limitation is currently down to policy requirements rather than equipment availability. Temporary access into these sizes would provide considerable cost saving within this size range. Discussion / Conclusion At this stage there is no established geometry for the Leakage Sealant Application System, therefore the required final dimensions of the access system are unknown. The best-engineered solution is always to design a fitting to match the requirements of the tool to be inserted. Nevertheless, as this is not always a practical or cost effective solution it is necessary to design the equipment for insertion using existing equipment. This project is focused on supplying a live access and cost effective remediation method for larger diameter mains, and as such, both temporary and permanent fittings will be applicable under given circumstances. It is understood that consideration is given to the true value of preventative remediation and as such the costs involved in permanent fitting and the long term benefit versus long term requirements of temporary fittings. The potential increase in maintenance requirements for Tier III assets as these pipelines continue to age may mean an increased requirement for temporary drillings and excavations. The increased number of temporary drillings on these pipelines may give rise to additional issues especially in circumstances where network topography and local restrictions limit potential access locations. For the purposes of this feasibility a temporary fitting will be used, this utilises the most holistic access methodology in the ALH System Three Valve using a 160mm access hole. This causes more problems when looking at a solution for 36” to 48" metallic mains because of the ratio of size between the access hole and the main diameter. This high ratio poses significant technological challenges on design of the in-pipe sub-system. This section of the feasibility will have to be constantly reviewed during the next stage of project development to ensure that it is still achievable with the given size restraints.
Recommendations: 4. It is recommended that the in-pipe sub-systems are designed to gain access through a 160mm diameter hole. 5. It is recommended that SGN review the future cross project requirements of remediation and inspection work in relation to construction of permanent access points. 6. It is recommended that SGN review the diameter range of 18” and up to but not including 24” and the quarter diameter access requirements in relation to full circumferential clamps and permanent access valves.
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2.2 Access System Aim The aim of this section of the feasibility study is to identify if equipment already exists that allows no gas insertion of large diameter equipment such as a CCTV and leakage sealant system. Where no equipment currently exists, the aim is to recommend a suitable system or development solution. Objectives The objectives of the access system feasibility study are to; Identify what is required from an access system to work in conjunction with a CCTV and leakage sealant system. Identify what are the critical aspects of an access system Identify what access systems are currently available Recommend an access system or a ‘best fit’ for development Identify potential information required to confirm feasibility success. Research Undertaken The research was carried out by;
Web Searches Web searches identifying existing fittings that meet the objectives. Talking to Pipe and Fitting Manufacturers and companies worldwide. Workshop Testing Testing concepts with larger diameter pipe within a workshop environment. Attending worldwide pipe seminars Consultation with in house gas engineers. Talking to global supply and procurement companies
There are generally only a few reasons to access metallic pipe under live conditions through an access fitting, normally access is required for;
Flow stopping operations Insertion of CCTV equipment Insertion of test equipment / bypass Syphon Gas quality checks
As such, there are few manufacturers of current insertion equipment. The main companies within the UK are WASK, ALH Systems Limited, Pipetech, and Synthotech. Synthotech are primarily concerned with the insertion of CCTV/Robotics and test equipment while the others mainly supply flow stopping and bypass equipment. The requirement for the access system will ultimately be determined by the size of the complete Remote Sealant Application system and the subsequent agreed access fitting. For the feasibility study, the outline performance specification will be used to identify appropriate access requirements. From practical experience and the global technology watch it can be seen that the largest bore possible is most suited for robotic application within gas mains. Therefore, branch saddles and tees provide the greatest chance of successful application. However, these provide a permanent access and egress fitting, it is important to focus on the smaller temporary access fittings as described in the previous section. The access and glanding system needs to meet a number of criteria, these criteria are generic and would apply to a wide range of device designs.
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Final Project Report
Allow easy insertion into the gas main To direct the in pipe system in a chosen direction Be scalable for 18” to 48” metallic mains (if required) Have good robustness and security while attached to the main Ensure pressure tightness during operational use
Comparison of technologies The design of an Access System and Access fitting are linked by the development of the Remote Sealant application system. The ultimate size and geometry of the tool has a critical impact upon the use and choice of the access systems and fittings. This relationship is depicted in Figure 7.
Pipe Size
Size/geometry Constraints
Access Fitting
Device
Size/geometry Constraints
Access System
Figure 7 – project development summary
The access fitting is assumed to be a predetermined item as the cost of developing a new system would be prohibitive to most projects. Therefore the access system is determined by the current approved list of access fittings and the final design of the Remote Sealant application device. The existing access systems that were viable for use with this project were
Synthotech, SynthoTrax Vertical Insertion System 18” to 48” metallic mains ALH System metallic Flow Stop Equipment Pipetel Explorer CISBOT Access System
For a full list of entry systems reviewed, See Appendix C Technology Watch Findings Synthotech and ALH Systems have UK gas approval for use at 2 Bar. Both systems are able to use the ALH System Three access valve, and with adaptors can be connected onto permanent standard access valves. Both the ULC Robotics and Pipetel explorer use a custom angled wrap around clamp that can be used at medium pressure. These access systems have not been designed for vertical insertion and are not approved for use on UK Gas networks. Size of system in relation to size of main The size of the access system inherently linked to the total size of the in-pipe systems rather than the size of the main. The choice of access fitting is related to the size of the main as seen in the first part of this feasibility study. Therefore the cross sectional size of the in pipe system is a factor of the largest access bore (using a
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Final Project Report standard existing fitting) and the length is limited by a ridged bending radius within the main (For rigid chassis robotic platforms). Glanding System Where the units are tethered the glanding system needs to allow for a ‘running seal’. This is a seal that sits around the CCTV camera feed/sealant delivery tube. In some circumstances, sealing efficiency can drop below 100 % due to constant movement and debris. Any glanding system should maintain minimal movement of gas or fluids either in or out of the pipe while producing a safe working environment in and around the excavation. An un-tethered device needs wireless control with onboard power, but has the advantage of not needing a running seal particularly required at higher pressures.
Figure 8 – Synthotech SynthoTrax being vertically launched into a 36” medium pressure gas main
Figure 9 – PipeTel Explorer launch assembly and angled valve
Figure 10 – ULC Robotics CISBOT launch assembly Figure 11 – ALH system twin bag launch system
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Final Project Report Gap Analysis The identified systems theoretically all have the capability of working with in-pipe systems. These systems would have to be evaluated in line with geometrical constraints of the final in-pipe systems as highlighted in the design tree (Figure 7). All the systems have similar capability of between 150mm and 160mm diameter access holes. Pressure capability for running seals within this project is 2 Bar which all systems are able to cover. Discussion / Conclusion There are current glanding systems available that could be implemented at the required pressure ratings. However each system is designed around specific equipment. Without the final dimensions of the in-pipe systems current access systems cannot be reviewed for applicability. Recommendations It is recommended that the access system choice be made against the final in-pipe device, whether this is a specific or a current applicable system. The access system should minimise excavations, the preference methodology for this would be a vertical insertion system. A vertical insertion method has the additional benefit of being particularly compatible with keyhole excavation techniques.
Figure 12 – Schematic of an Access System
2.3 In-pipe Robotics Platform The in-pipe Robotics platform will form the basis for the internal sealing and inspection sub-systems. The platform will be required to supply all necessary support to internal sub-systems including power, data control relay and stability. Aim The aim of this section of the report is to investigate the requirements and potential solutions of the internal robotic platform. This will be the basis of the internal robotics package that will provide locomotion, power, and stability to the sealing system.
Objectives The objectives of this section are to;
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Identify what is required from a propulsion system for 18” to 48” metallic mains. Identify what are the critical aspects of a propulsion system. Identify what propulsion systems are currently available. Identify what are the critical aspects of a stable work platform Recommend a propulsion system and stable work platform combination for use or development. Identify potential information required to confirm successful application of the feasibility study success.
Research Undertaken The research undertaken investigated locomotion systems available, which are considered appropriate for this application. This research included: Visiting
Trade Stands - (Water and Waste Exhibition & Drain Trader Exhibition, World Gas, No-Dig etc.). Reviewing existing technology on sale worldwide Robotics companies within worldwide utilities Reviewing emerging technology within the global market
Web Searches Global technology search. Identifying any existing systems that meet the objectives. Developments by universities and research houses that offer practical solutions. Visiting suppliers and hiring equipment for test Operational Environment This section of the report will identify the requirements of the in-pipe Robotics platform. Platform Loading While a device operates within the gas mains a number of forces will act upon it in various directions. These can impose various limitations on the complete system - most notably application distance from a single access point.
Figure 13 – Platform Loading Schematic Bu = Buoyancy FT = Tractive effort FD = Drag force induced by fluid motion. (May act in either direction dependant on flow direction) FCa = Resistive frictional force from tether cable. FCo = Resistive frictional force generated through device and pipe contact. 20
Final Project Report Mg = Device weight. Aerodynamic Drag Aerodynamic drag that would act upon the in pipe robotic platform may be either beneficial of detrimental depending upon flow direction. The magnitude of the effect that this would have on the can be estimated through the application of the drag equation. 1 𝐹𝐷 = 𝜌𝐶𝐷 𝑢2 𝐴 2 As the unknowns include final device geometry and in-pipe conditions, only assumptions can be made. In the equation above 𝐶𝐷 represents the coefficient of drag (The coefficient of drag takes into account both skin friction and form drag). This figure is unique for a given shape and represents the aerodynamic properties of the shape. The coefficient of drag for a given shape is usually determined experimentally, but as the final device is not available for evaluation, this value is tabulated below.
This equation represents an idealised estimation where fluid compressibility, heat transfer and such are not accounted for.
Key. A = 80mm diameter object 0.7 Kg/m3 Fluid Density 0.3 Coefficient of Drag B = 160mm diameter object 0.7 Kg/m3 Fluid Density 0.4 Coefficient of Drag C = 50mm diameter object 1.4 Kg/m3 Fluid Density 0.6 Coefficient of Drag D = 320mm diameter object 2.1 Kg/m3 Fluid Density 0.8 Coefficient of Drag
Figure 14 – drag forces in a gas pipeline. Assumed coefficient of drag 0.5
The aerodynamic effects on an in-pipe device will be significantly less than those involved with traction and cable friction (overleaf). This remains reasonable where there is an appreciable difference in cross sectional area of the main and in-pipe device. As a consequence of drag and the subsequently induced flow turbulence the in-pipe platform will result in a downstream pressure drop. As the system is intended for use under 'live gas' conditions the in-pipe system should maintain a minimal satisfactory pressure drop within the gas flow. This can be evaluated throughout design via methods including computational fluid dynamics to ensure compliance with operator requirements (see Figure 16). Tether Resistance Most in-pipe systems are 'tethered' to an external power source, to display CCTV feeds and to relay information. This tether gives rise to a resistance related to the weight and friction coefficient of the cable used. The associated resistance acts to limit the maximum application distance based upon the traction
21
Final Project Report available from the in pipe robotic platform. An additional circumstance of this resistance is limited platform speed, as greater torques and thus lower speeds are needed to propel the in-pipe platform. The total frictional force applied to the robotic platform is estimated by the static friction equation below. Is should be noted that generally kinematic (moving) friction is generally less than static friction. 𝐹𝐶𝑎 = 𝜇𝑀-𝑔𝐿 To minimise the limiting effects of friction at long lengths the tether should be made or coated with low friction materials and be as lightweight as possible.
Figure 15 – frictional resistance Vs application distance As an example, typical values of static and kinematic friction between steel and a HDPE coating can be around 0.36 and 0.23 consecutively. It is highly unlikely that the upper limits of cable weight and friction coefficients could be accounted for using the free body weight of the robotic device alone. From an ergonomic perspective a 25Kg weight in-pipe robotic platform would ultimately give a maximum tractive capacity of 245 N (based on a Coefficient of friction of 1 which is an over estimate). Pipe Gradient The gradient of the gas mains will affect application distance through increased resistance or additional drive. In either situation, traction will be reduced as a function of the gradient (through a diminished perpendicular reaction). The majority of large mains are approximately level diminishing the severity of these effects. Additionally where gradients exist, the access location can be offset to gain additional application distance 'downhill' to compensate the reduced application distance 'uphill'. Tractive effort There are a variety of methods available for producing a tractive effort within a pipe. The scales of the forces that can be achieved vary between methods and systems, i.e. platform to platform. A variety of methods are discussed below in propulsion systems with some typical expectations.
22
Final Project Report
Figure 16 – example of a concept SynthoTrax ISP spray unit flow characteristics in an 18” diameter pipe Comparison of Technology Propulsion Methodologies Manual push - pull Push Rod systems may be used for Camera Inspection, remedial Spraying or Sealant Leakage Injection. For this example, a typical Push Rod CCTV System has been used as the basis of the evaluation. In a Push Rod inspection system, a camera head is attached to a length of semi rigid cable. This cable is passed through a glanding system into a live pipe. By 'pushing' more cable through the glanding and into the pipe the camera head is moved along the inside of the pipe allowing inspection up to a distance of around 100m. The glanding system allows live access to the pipe without allowing the contents of the pipe to leak into the atmosphere. When conducting a push rod inspection there are number of limiting factors on the insertion distance. These are;
Angle of the insertion system relative to the pipeline. Diameter of the host pipe. Diameter and rigidity of the insertion coiler. Main condition and contamination level - debris, weasel etc.
To gain the maximum survey distance the diameter and rigidity of the cable should be maximised while the angle of insertion should be minimised (assuming that there are no pipeline bends). Increased host pipe diameters affect survey distance negatively as the push rod cable buckles and coils within the pipe to a greater extent through increased buckling modes (Frequency of coiling). It is also important to minimise the effects of friction between the camera head/cable and the internal pipe surface (low Coefficient of friction).
23
Final Project Report Angle of Insertion
75o
65.5o
Diameter of Host Main
12” metallic
12” metallic
Diameter & Rigidity of Insertion Coiler
9mm fibreglass
9mm fibre glass
Insertion Length achieved
30m
55m
Figure 17 – manual push pull issues In larger diameter pipes (greater than 18”) push rod systems are very limited in application distances from an access location. However, within larger mains a larger diameter, significantly more rigid plastic tubing and rods are available. Even so, this methodology is typically limited to around 55 meters in a large pipe such as a 48” main. Greater distance can be achieved by pulling equipment though pipelines, however this is usually only done under 'dead' or gas free conditions. It is possible that following development this could be applied in live pipelines, this will be discussed under the passive drive section to follow. Traction based Devices. The second method of propelling a platform down a pipe is a crawler based system. These are usually powered track or wheel based vehicles that are inserted into the pipe and pull a tethered cable behind them (Some systems do not require a tether). Crawler systems are larger and more powerful than manual push rod systems. Generally, the increased capacity for lighting enables them to inspect larger diameter pipes with better results. As crawler systems are self-propelled, they are usually capable of travelling greater distances than Push Rod systems. Application distances are typically in the range of 100m to 500m. The crawler platforms can typically be outfitted with various inspection cameras and other tools for drilling, spraying, assessment and in some cases can have other added functionality such as laser profiling devices. Due to the added complexity of crawler systems, they are larger than Push Rod systems the minimum diameter pipe that they can survey is around 150mm. Crawlers also have greater requirements for live launch i.e. larger access fitting bores than more traditional push rod systems. There are a number of crawler systems in the gas industry that can be used under live access conditions. They generally gain access via a cut out section, however some have the ability to be launched vertically through an under pressure drilling from ALH Systems Limited or Pipeline Technology Limited for example. One of the issues with the current range of crawlers used in global gas distribution networks is they are based upon standard drainage crawlers, and as such are too large to easily gain access and egress from the pipelines. Synthotech have an existing robotic vision system designed specifically for live access through a 6” BSP tapping using an ALH Systems III drilling base and machine. ULC Robotics may also have a live vertical launch capability (however, at this stage this is currently unconfirmed).
24
Final Project Report
Figure 18 – SynthoTrax Platform with actuated pan and tilt inspection camera Figure 19 shows a pictorial representation of passive and driven systems currently in use. These systems are classified into several elementary forms according to moving patterns; most of them have been designed depending upon specific applications.
Figure 19 – drive mechanisms Classifications are (a) Pig type. (b) Wheel type. (c) Caterpillar type (Synthotech crawler). (d) Wall-press. (e) Walking type. (f) Inchworm type. (g) Screw type. Passively driven devices In the water, petrochemical and oil industries long survey lengths have been achieved through utilizing the fluid flow within the pipe (Pigging) as a propulsion mechanism. This is not considered applicable due to the inherent pressure drops that this may cause within the networks. Although the flow within the gas pipes may not be capable of carrying inspection equipment or a work platform along a long stretch of pipe it may be able to carry a guide wire with much less weight. This guide wire could be 'captured' at a second insertion point and then used to pull the working platform through the pipeline. More details are included in the design matrix included in the section 11. Current in-pipe Robotic Platforms Some of these devices (SynthoTrax, Kiwa Gas & Endo Services) have been previously reported in a 'Feasibility Review into CCTV Survey Capability inside a 4" Metallic Gas Main under Live Gas Conditions at Operation Pressure up to 2 Bar for Scotia Gas Networks', 9th August 2012 25
Final Project Report Kiwa Gas Technology Kiwa Gas Technology is the main Dutch gas research and development company who develops products for all of the main Dutch and European gas companies. They currently have a development called the PIRATE (Figure 20). This is an Autonomous Inspection Robot for Gas Distribution Networks. It is a series of actuated arms that ‘clamp’ the pipe as it is left to negotiate the network. This system has significant potential for use as the articulation should make it possible to gain access and egress from a pipe. It will also be able to transverse the range of pipes required. After a visit to Kiwa in Holland it became evident that the product as a vehicle was a great success. However the development of the PIRATE had not allocated any space for systems such as CCTV or leakage sealant injection. The development team were unable to confirm where or when the product may have such platforms available. Despite the system not currently having a CCTV application, the PIRATE is a contender for a Remote Sealant Application system, pending the final size and configuration of the leakage sealant injection system and compatibility with any camera module. This device is particularly applicable to this application because of its ability to negotiate tight bends which would make it well suited to accessing pipes through a reduced bore, allowing for a much longer vehicle than a ridged chassis would permit. The PIRATE has an open chassis design, the control and automation elements are be exposed to fluid flow. This may cause problems if debris/water were to ingress into drive motor gears or corrosive / aggressive fluids (such as the leakage sealant) into the electronics. The PIRATE is also designed for small size low pressure gas pipes so therefore some modification to the current design would be necessary for larger diameter gas pipes.
Figure 20 – Kiwa gas robot The PIRATE concept is based on a wireless flexible wall press platform and has particular benefits in range over tethered alternatives (potentially capable of 1000m). This system would be particularly suited to application within metallic mains as the internal walls of the pipeline provide a waveguide to aid wireless data transmission at certain frequencies. However requirements associated with sealant application is sealant supply, drilling (if required) power, would critically increase the complexity of the in pipe device.
Endo Service Endo Service is a German company that make the CRAB ROBOT System. It is an active traction remote-controlled crawler with builtin camera-modules and illumination, for visual inspection for long pipe-systems. Different types of crawlers are available for pipes diameters from 85mm to around 600mm. the CRAB ROBOT (Figure 21.) can negotiate small tube-bends with a bend radius greater than 1.5 x pipe diameter. This device is steerable and can inspect pipes from 85mm inside diameter and manoeuvre vertically up and down into pipeline systems. The CRAB ROBOT, once again has potential as a standard vehicle for the CCTV and leakage sealant injection system as it clamps the inside of the pipe wall, to gain increased traction. However access for the CRAB ROBOT would be a problem with this device as the system is designed for end on access only, and therefore could only
26
Figure 21. Endo Service Crab Robot
Final Project Report be launched through a like size bore, and would require a 1.5 x diameter bending radius into the pipeline. In discussion with Endo Service, the company would be interested in developing the system so that it has reduced access diameter, in part due to limited sales they have had because of this problem. However, the company had not succeeded so far with the alteration and were not able to put an anticipated success rate on a project with this aim. Explorer and Explorer 2 The Explorer is a long-range un-tethered wireless pipeline crawler that has live launch capability (Figure 22 to 23). The device was originally developed by Carnegie Mellon University with funding from the American Department of Energy (DOE) and the Northeast Gas Company. The device is now available through PipeTel who have commercialised the device. The Explorer is now available through them and is offered in two formats, the explorer 6/8 and the explorer 10/14. The explorer 6/8 can inspect pipes 6" to 8" while the explorer 10/14 can inspect pipelines from 10" to 14". PipeTel are also currently developing an Explorer 20/26.The PipeTel also states that pipes up to 36" can be inspected. The increased functionality of the Explorer 2 has been included within these devices and they both offer NDE inspection as well as a CCTV inspection. The Explorer 6/8 became available through Pipetel in December 2010 while the Explorer 10/14 became available in June 2011. The development work was under taken between 2001 and 2006.
Figures 22 and 23 – PipeTel Explorer 6/8 (L) and PipeTel Explorer 10/14 ®
The Explorer devices can be vertically launched into a steel gas line through either a 45° or 90° custom clamp fitting. The Explorer is not stated to have any specific pipe usage and is specifically a long range inspection device for un-piggable metallic natural gas transport and distribution pipelines. The wireless method of communication that the explorer device uses is based on using the metallic pipeline as a waveguide to transfer RF signals to and from the device. The device does not seem to have any specific platforms for adding a leakage sealant injection platform. PipeTel do not currently offer the Explorer devices for sale and rather offer a pipe inspection service utilising these devices. Pipemouse The Pipemouse (Figure 22-23.) is a gas inspection device based on similar principals to the Kiwa gas robot and the Explorer. The Pipemouse is another segmented modular device described as a 'train'. The 'cars' of the train are used to house all of the necessary components i.e. batteries, electronics and inspection equipment. Due to the modular and flexible design of the Pipemouse this device is also able to negotiate a number of un-piggable pipe configurations including the ability to negotiate mitred elbows in back to back out of plane orientations, partially ported valves and unbarred branch connections.
27
Final Project Report The Pipemouse is propelled using an adaptable wheeled wall press mechanism described as a triad, this is the same principle employed by the Kiwa gas device.
Figure 24 – PipeMouse Schematic
Most in pipe inspection devices use electronic tethers (SynthoTrax Inuktun VT 300 etc) the explorer devices, Kiwa gas device and Makro (a wireless drainage inspection device) are untethered. The Pipemouse uses the combination of a fibre optic tether for data transmission and on board batteries for energy storage. The use of a fibre optical tether within the device raised some problems. From the Pipemouse report fluid drag acting on the tether caused signal loss and damage to the tether where mitred bends were encountered. Ultimately the use of the fibre optic tether has benefits over electronic tethers and wireless devices autonomous or not. Wireless data transmission requires significant amounts of power which, in battery operated device, can be a significant energy drain. Although larger electronic tethers are capable of powering devices the range becomes limited through tether friction and voltage drop. A fibre optic tether would best be suited to a situation where large distances are to be covered and other communication methods such as wireless are not suitable or economical. To minimise the risks involved with a fibre optic tether it would be best implemented within in a straight pipeline without obstructions.
Figure 25 – PipeMouse Picture The Pipemouse was funded by the American Department of Energy and the Northeast Gas Association. The research contractors were Foster Miller and GE Oil and Gas. The major design challenges of the project were enabling the device to pass partially ported valves and negotiate mitred bends, both of which are not currently believed to reside within the remits of this project. Pearpoint Pearpoint by Radiodetection offer a range of crawlers for the drainage industry. They offer many other products and services to the water and gas industries including leak detectors, cable detectors, dryers and flow monitors. Ibak Ibak are an engineering firm that offer a range of drainage inspection equipment ranging for camera heads to full van fit out systems and specialist software. The equipment the offer generally has a limited range and limited pressure tightness. Although the crawler platforms they offer would fit within the pipelines there is currently no live access available. 28
Final Project Report Inuktun Inuktun are a Canadian company that offer range of inspection equipment. The Versatax 300 is the greatest performing device that they offer with a range of 1981m from a single access location. The VersaTrax 300 is a tethered crawler with two traction units. ECA Hytec ECA Hytec produce a range of equipment for underwater, nuclear and in-pipe applications. They offer many remotely controlled devices with a range of abilities including subsea inspection, nuclear inspection and pipeline inspection crawlers. These systems are generally too large for holistic pipeline insertion. Synthotech SynthoTrax™ The Synthotech crawler system has been designed for live access through a 6” BSP tapping for access into metallic pipe. This would allow direct access into 24” and above or through a full encirclement clamp for 18” to 24” metallic mains. CISBOT CISBOT is a system that remotely injects anaerobic sealant into cast iron mains under 'live gas' conditions. ULC robotics potentially provide two systems, a push rod based systems for small mains and a traction based systems for large mains. Inspector systems Inspector Systems Rainer Hitzel produces and operates a range of in-pipe robotics platforms. These systems are generally used within the process industry for both direct inspection and NDT related maintenance operations. The systems can be supplied with an array of tooling to perform internal grinding and milling operations and show the potential for augmentation with additional capabilities.
Figure 26 – Inspector Systems Pictures However these systems have been developed for a specific purpose and they are applied through cut out sections. The systems are sized close to that of the host pipe which would mean an increased pressure drop would be seen in 'live gas' conditions. Gap Analysis The outline performance specification for the in-pipe platform is detailed below; 1. 2. 3. 4. 5. 6. 7. 8.
Capable of application in mains between 18" and 48" Capable of launch through standard pipeline access methodologies Not to be adversely affected by the sealant medium used for injection into the joint Maintains manoeuvrability within pipelines allowing negotiation of obstacles To travel and function within pipelines at distances of 200m To provide the required stability for sealing (inc drilling*) operations To operate within an atmosphere of Natural Gas To be used at pressure of up to 2 bar
The capabilities of the most applicable technologies from this section of the report are highlighted below. 29
Final Project Report Outline Performance Specification
In-pipe Platform CISBOT (6"12")
CISBOT (16"- SynthoTrax 36")
Mainspray
Inspector Systems
1
No
Yes
Yes
Yes
No
2
No
U/N
Yes
Yes
No
3
Yes
Yes
Yes
Yes
U/N
4
No
Yes
Yes
No
No
5
No
U/N
Yes
No
Yes
6
Yes
Yes
Yes*
No
Yes
7
Yes
Yes
Yes
Yes
U/N
8
Yes
Yes
Yes
Yes
U/N
Figure 27 – in-pipe platform comparison table U/N – unknown, *tested in 8” cast main
Within this section of the report, the SynthoTrax was the only system to meet the outline performance specification. Should the 'Big CISBOT' be available then this system could meet most of the requirements for the in-pipe platform and more general project requirements up sizes of 36". The 6" to 12" CISBOT would not be applicable due to its size and limited application distance. Further contact with ULC Robotics is required to investigate the capabilities of the Large CISBOT system.
30
Final Project Report Company
Device Name
Description
Maximum working Pressure
Minimum Pipe Size
Max. Application Distance
Camera System.
Sealant Application
Internal Drilling
Live Launch Capability
Endo Service
Crab Robot system
An in pipe video inspection system
-
50mm - 500mm
100m
Pan and tilt
No
No
No
InukTun
VT100
A portable pipe inspection system
30m/3Bar
100mm - 610mm
183m
Inuktun spectrum 45
No
No
No
InukTun
VT150
A long range pipe inspection crawler
30m/3Bar
150mm in line chassis 300mm parallel track
160m (457m optional)
pan and tilt & static rear
No
No
No
InukTun
VT300
A long distance pipe inspection crawler
30m/3Bar
300mm
1981m
Spectrum 90 & 2 Axial
No
No
No
InukTun
Crystal cam push cam
Push Rod inspection equipment
-
50mm - 500mm
90m
Inuktun Crystal cam
No
No
No
InukTun
Micro VGTV
A variable geometer crawler
30m/3Bar
above 317
90m
Yes
No
No
No
InukTun
NanoMag
A magnetic pipe inspection crawler system
-
above 105mm
30m
Spectrum 45 pan and tilt
No
No
No
InukTun
VT450 TTC
An inspection crawler with a manipulator arm
-
Above 367 (Min entry 381)
160m (457m optional)
Pan and Tilt
No
No
No
Pearpoint
P420
A 6-wheel small pipeline crawler
-
150mm-750mm
-
Pearpoint P494f of P494z
No
No
No
Pearpoint
P400
A large 4 wheel tractor unit
-
300mm
-
Pearpoint P494f of P494z
No
No
No
Pearpoint
P448
A large 4 wheel tractor unit
-
500mm
-
Pearpoint P494f of P494z
No
No
No
ALH Systems
Mainspray
A Push Rod sealant application system
2 Bar
~50m
No
Yes
No
Yes
ULC Robotics
PRX250k
A pipe inspection powered push rod system
4.13 Bar
101.6mm
152.4m
wide angle camera
No
No
Yes
ULC Robotics
CISBOT
A Cast Iron Joint Sealing Robot
2 Bar
12" (36")
90m (305m)
Custom Internal CCTV
Yes
Yes
Yes
Ibak
KRA 85
A drainage pipe Inspection traction unit
1 Bar
225mm
-
Ibak axial or Pan and tilt
No
No
No
Ibak
KRA 75
A drainage pipe Inspection traction unit
-
150mm
-
Ibak axial or Pan and tilt
No
No
No
Ibak
KRA 65
A drainage pipe Inspection traction unit
-
100mm
-
Ibak axial or Pan and tilt
No
No
No
Ibak
T 86
A drainage pipe Inspection traction unit
-
200mm
-
Ibak axial or Pan and tilt
No
No
No
Ibak
T 76
A drainage pipe Inspection traction unit
-
150mm
-
Ibak axial or Pan and tilt
No
No
No
Ibak
T 66
A drainage pipe Inspection traction unit
-
100mm
-
Ibak axial or Pan and tilt
No
No
No
Synthotech
SynthoTrax
A live inspection/evaluation robotic platform
Approved at 2 Bar tested to 6 Bar
355mm
500m
Synthotech Pan and Tilt
No
Yes
Yes
PipeTel
Explorer
A long distance wireless live launch inspection device for metallic gas pipes
45 Bar
6"-8" / 10"-14"
Case studies up to 1463m
Yes
No
No
Yes
31
Final Project Report
Discussion / Conclusion Standard push rod systems do not meet the project requirements, as the maximum insertion distance is too short from a single insertion location. Passively propelled systems are not considered viable due to the potential for increased pressure drops over the remediation zone during working when compared with other methodologies. It would be mandatory to use an active traction based platform with a 'wall press mechanism' to provide adequate traction and stability. Free weight traction could not meet the frictional forces expected over the application distances required within practicable weigh limits. Current motorised units can currently meet the insertion distances required under live conditions, however with the exception of the 'Big CISBOT' there is not a system that could currently support internal drilling of mains from 18" to 36". There is no system capable of joint drilling within a 48" main. Despite this, the Mainspray system is capable of anaerobic sealant application within all pipe sizes required but at limited application distances. As drilling of the joint is a methodology of improving the sealant delivery, it may not be completely necessary (if the sealant could be delivered effectively achieved by another method). Due to the stability requirements of a drilling platform and the inherent access limitations imposed by a standard access methodology a system that does not need to drill the joint to apply sealant may be more robust through increased simplicity. Recommendations There is currently not enough information for the feasibility to comment on the suitability of the ‘Big CISBOT’ and therefore this has been left out of the communication and recommendations. Although the SynthoTrax system meets all of the performance requirements from this section of the report, technology developments would be required to allow a complete system to meet all of the performance requirements from every section of this report. Based solely on this section of the report the recommendation would be the use of the SynthoTrax Robotic platform.
2.4 Sealant Application System Aim The aim of this section of the report is to investigate the requirements and potential solutions for the internal sealant application sub-system. This sub-system will be responsible for the application of the sealant to the joint. Objectives The objectives of the access system feasibility study are to;
Identify what is required from the sealant application system Identify what joint sealant systems are currently available Identify the limitations of currently available systems Recommend a sealant application sub-system
Research Undertaken The research was carried out by,
32
Web Searches Web searches identifying existing fittings that meet the objectives. Talking to Metallic Pipe and Fitting Manufacturers and companies worldwide. Workshop Testing
Final Project Report
Testing concepts with Tier 2 diameter Metallic pipe within a workshop environment. Attending worldwide pipe seminars Consultation with in house gas engineers. Talking to global supply and procurement companies
Comparison of Technology External Injection Examples of External injection systems include Synthotech I-Seal and ALH Main-seal. These systems use an anaerobic sealant to seal the leaking joints from the outside of the pipeline. These systems therefore require an excavation onto each joint that is to be sealed.
Figure 29 – ALH mainspray injection system The injection guns used for sealant delivery can typically achieve injection pressures of between 2.5 and 4 Bar. Encapsulation Encapsulation is a method for sealing leaking cast joints. This methodology involves excavating around the joint and sealing externally via encapsulation with a number of possible materials one example of which is Series 6 from ALH systems.
Figure 30 – an example of encapsulation CISBOT ULC Robotics currently has a system for live sealing of cast iron joints. CISBOT is a system that drills into the 'yarn' of a bell and spigot joint and injects the aerobic sealant 'Anacure'. The standard CISBOT can be applied to cast iron mains from 6" to 12" in diameter, cover 24 joints per day and a distance around 91m of gas main from a single access location.
33
Final Project Report The system is supplied by ULC robotics as a contracted service that is paid per joint (within North East America). Pipeline Access The CISBOT system uses a custom permanent encirclement fitting with an excavation of 1.2m by 1.8m. This fitting is used to house the drill that forms a hole within the main as well as the launch and glanding system for the in pipe platform. These fittings can be inclined at either 45 or 30 degrees to achieve the distances required via a 'push rod' methodology.
Figures 31 and 32 – CISBOT access fitting (L) and CISBOT drill (R) In-pipe Robotics Platform The standard CISBOT platform is a push rod system that is propelled within the pipeline by a glanded push rod. The platform is manipulated along the pipe by an electronically controlled automatic feed system. CCTV systems are used to aid the alignment of the system with the joint that is to be sealed. To seal a leak, a hole is drilled from the internal wall of the main into the 'yarn' of the joint. Once completed, sealant is injected into the joint using the same in-pipe platform.
Figures 33 and 34 – CISBOT 6 to 12” push rig (L) and CISBOT in pipe video shot (R)
Details on the larger CISBOT are scarce, information on the developments have been removed from the ULC website over recent months and has been reported to be under development with National Grid. From previously obtained literature the larger device is capable of locomotion and sealant injection at any circumferential location within the gas main as well as being launched vertically into the pipeline. Mainspray Mainspray is a system supplied by ALH systems. Mainspray uses an umbilical based push rod to deliver an anaerobic sealant to the joint of a metallic gas main. A spray head is inserted into the gas main using a no-gas glanding. This head is pushed along the main the maximum distance possible. On retrieval a detector signals that the main has increased in thickness, (this
34
Final Project Report occurs at the bell and spigot joints) a spray of anaerobic sealant is then applied to the local area. This system uses capillary action to draw the anaerobic sealant into the 'Yarn' of the joint and achieve a seal.
Figure 37 – ALH systems main spray
Mainspray for large diameter mains (24" - 48") uses additional equipment to further increase the likelihood that the sealant is delivered to the required surface effectively. Gap Analysis The outline performance specification for the Sealant application system is detailed below; 1. Capable of application within mains between 18" and 48" 2. Capable of launch through standard pipeline access methodologies 3. To function within pipelines at distances of 200m 4. To operate within an atmosphere of Natural Gas 5. To be used at pressure of up to 2 bar. 6. To Seal joint effectively with/against the expected flow of gas within the main 7. Able to seal all available joints from an insertion (No re-launches) 8. Be compatible with existing approved LC9 Sealants 9. Able to seal a leaking joint up to a test pressure of 3 Bar. The capabilities of the most applicable technologies from this section of the report are highlighted below. Outline Performance Specification
Sealant System CISBOT (6"12")
CISBOT (16"- Encapsulation 36")
Mainspray
External Injection
1
No
Yes
No
Yes
No
2
No
U/N
No
Yes
No
3
No
No
U/N
No
U/N
4
Yes
Yes
U/N
Yes
U/N
5
Yes
Yes
Yes
Yes
Yes
6
Yes
Yes
Yes
Yes
Yes
7
Yes
Yes
No
Yes
No
8
Yes
Yes
Yes
Yes
Yes
9
U/N
U/N
U/N
U/N
U/N
Figure 38 – joint sealant application comparison table (U/N – unknown)
35
Final Project Report Within this section of the report the Mainspray System was found to be the product that met the most of the application requirements. Should the 'Big CISBOT' be available then this system could meet most of the requirements for the Sealant application system and more general requirements in all but 48" mains. The CISBOT system does not meet the application distance requirements. The 6" to 12" CISBOT would not be applicable due to its size range and limited application distance. Discussion / Conclusion The report has not made the assumption that a drilled access hole into the yarn of the cast joint is a prerequisite for an effective repair. However, neither has the assumption been made that this would not affect remediation quality. One conclusion that can be drawn is that the application of an internal drilling system represents a greater technical challenge over a system that does not require a drilled entry point for sealant injection. Additionally a system that does not drill the joint maintains the greatest seal length possible as the 'puncture hole' used for sealant injection may create a new potential leak path. A system that was able to apply sealant without a drilled hole would also potentially be capable of a quicker remediation as drilling is a time consuming operation not required. Recommendation No single system could meet the performance for this section of the report. There is insufficient information regarding the 'big CISBOT' to draw any conclusions or recommendations as to its applicability within the scope of this project. In order to cover the full range of outline performance specifications a development would be required. The recommended action would be to develop the SynthoTrax architecture to seal the cast joints by, either; 4. Controlled Directional Spraying of Cast Joints 5. Point contact sealant injection into the Cast Joints 6. Drilled sealant injection into the Cast Joints
2.5 In-pipe CCTV Inspection Aim The aim of the CCTV feasibility study is to identify and recommend a suitable CCTV inspection system for use within the Remote Sealant Application Device. Objective The objectives of the access system feasibility study are to; Identify the outline performance requirements of a CCTV inspection system when for use with a leakage sealant injection system. Identify, review and assess current CCTV systems currently available for this application Recommend an existing CCTV system, or a CCTV system for development as part of the debris extraction system Recommend a device(s) for the complete system Research Undertaken The research involved investigated CCTV systems available, which could be considered appropriate for this application. This included: Visiting: Trade stands – (water and waste exhibition and drain trader exhibition) Reviewing existing technology on sale worldwide
36
Final Project Report
CCTV companies within worldwide Reviewing emerging technology within the global market Testing concepts, in particular with larger diameter cast iron pipe, within a workshop environment Testing concepts, in particular with larger diameter cast iron pipe, within a field application environment SynthoCam™ archive video review SynthoTrax™ video review Reviewing of SynthoCam™ video footage from metallic pipe
Review of CCTV Technologies Cameras For effective application within this project, a camera system must be capable of high quality video capture with pan and tilt capabilities for accurate internal joint assessment. If there is to be a camera system for use with leakage sealant, then it must not be adversely affected by swarf, debris, gas main particulates and sealant spray. The camera system must be able to withstand a working pressure of 2Bar and remain ingress protected accordingly. The camera system(s) must also be compatible with all other aspects of the project i.e. access, glanding, sealant injection & locomotion systems. The most effective solution would be a single camera system that could be applied from 18” to 48” mains, however it is likely that multiple camera feeds will be necessary for precise control of the in-pipe device. There is a variety of cameras available for use in harsh environments. These include but are not limited to drainage cameras, live gas cameras, borehole cameras, nuclear inspection cameras and underwater cameras. All cameras have the same variables. These need to be assessed to ensure that the system is fit for purpose. Lighting It is possible for a camera to have excellent vision outside a pipeline (main), yet provide limited vision inside. This is due to the quality, quantity and arrangement of the light available. A small camera module may still provide a ‘good’ picture in a large main providing it has sufficient lighting and focal length to allow it to focus on the ‘whole’ circumference of the main. Diffused lighting and/or dimming capability is essential when looking at fittings, components and joints within gas mains, this is due to the reflection that concentrated lighting can cause especially where the angle between the light source and camera lens allows light to reflect directly into the camera. Operating pressures, flow captured debris, fluid mediums, fluid flow and dynamics in relation to the CCTV unit will all have a potential negative effect on the quality of the vision. Contrast and Brightness One of the main criteria for a quality picture is the configuration of contrast and brightness specifically when considered in relation to the pipeline material. CCTV application within metallic pipes can be difficult due to the variations within the pipe including service texture, dust, debris and colour. Lighting that is used to illuminate the pipe must be powerful enough to provide full circumferential lighting while allowing maintaining a low contrast, avoiding high areas of lighting flux that would reduce the overall picture resolution. TV Lines Television Lines (TVL) is a specification of a camera relating to the image quality, in particular the horizontal resolving power of a given device. A high specification of TVL for a device with correct lenses gives a better definition in captured images. Noise and interference CCTV camera data can suffer significant interference from background noise and electrical signals. Therefore, all tethered cables relaying video data should be shielded, balanced, or encapsulated, and all un-tethered systems need to operate at specific wireless frequencies. Aside from general visual disturbances, such as fluid
37
Final Project Report flow, interference from 'electrical noise' can affect picture quality. In short, specific technology is required to achieve full vision quality, with good colour and contrast, in both types of systems. Camera Vision With every camera system there are certain limitations factors for vision, and these need to be considered.
Gas conditioning agents Debris Power supply Gas pressure
Camera vision is traditionally axial meaning that it is forward facing and static, therefore blind spots and optical illusions may be encountered. A Pan and Tilt camera system can be remotely positioned providing a full forward view or circumferential directional view. A Fisheye camera is an axial camera that has an ultra wideangle lens enabling the full internal circumference of the pipe to be seen from a single view. Unclear vision can be caused as a result of the camera being pushed through debris, dust, water puddles or gas conditioning agents. To circumvent this camera skids are often used to lift the cameras into the centre of the pipelines. However due to access bore size restraints the inclusion of skids can be problematic on smaller pipe sizes.
Forward Facing Camera
Ultra wide angle 'Fisheye' lens
Pan and Tilt Camera
Figure 39 – schematic of forward, pan and tilt and fish eye camera views Drainage Cameras Drainage cameras are inserted into pipe networks via large access manholes. The non-live access point means that a skid can be used to lift the camera out of the dirt and debris, and allow it to travel over obstacles such as internal weld beads. Due to the lack of space restrictions, additional lighting can also be placed onto any skid unit and or camera. Interruption to gas flow rates is not an issue in drainage inspection as thus cameras can be significantly larger than those found in gas applications.
38
Final Project Report Live Gas Pipeline CCTV Equipment
Figure 40 – Synthotech pan and tilt camera and a Pearpoint forward facing camera Intrinsic safety Most cameras used within the gas distribution market are not intrinsically safe. There are currently only two intrinsically safe cameras commercially available. These are from ECA Hytec and Pearpoint. However, due to the restraints based around achieving the intrinsically safe ratings these cameras generally give a more limited image and have greater requirements for access into gas mains. Generally, systems used in the worldwide gas industry are not intrinsically safe. Utilising cameras that are not intrinsically safe is not an issue providing an approved access system is used in conjunction with robust work procedures. It must also be noted that any potential leakage is most likely to occur during the insertion of the tether/coiler. Most live launch systems use similar seals. Synthotech have seals with 2 and 4 bar approval. Borehole Cameras Two main categories exist within the scope of borehole cameras: Those used within deep drillings within the petrochemical industry Those used within shallower water drillings The standard specification of a water borehole camera shows no real advantage over the average drainage camera. A borehole camera is essentially a push rod inspection system with a skid unit and a non-ridged cable. Borehole camera cables do not need to be ridged because the cameras are deployed vertically under the influence of gravity.
Figure 41 and 42 – a Geovision borehole camera (L) and a U-Cam borehole camera system (R)
39
Final Project Report The Borehole cameras found within the petrochemical industry have maximum working pressures that are much greater than what would be required throughout this project. Due to the increased pressure that these cameras are capable of withstanding, these cameras are usually co-axial (meaning that there are two cameras; one looking along or down the pipe and one looking at the pipe wall) rather than Pan and Tilt. The Borehole cameras can also become sufficiently long with included lighting i.e. built-in, that access to the pipes concerned with this project would be more complex than either a gas or drainage cameras that meet the required application requirements. Comparison of CCTV technologies Following a review of CCTV technologies looking at operating pressures, size, reliability, and scalability, six companies products have been selected for consideration;
Radiodetection for Pearpoint cameras ECA Hytec Synthotech for SynthoCam cameras Inuktun Ibak ULC Robotics
Key comparisons metrics for CCTV:
Camera quality Lighting capability Size Vision capability Operation in potentially hazardous areas i.e. gas Pressure Rating Ability to be used in water and gas
A comparison of available CCTV inspection cameras is available within the appendix There are multiple possibilities for a camera system as a part of the complete device. Due to the likelihood that several live camera feeds will be required it would be advantageous if these systems could be based on the same architecture to increase system simplicity and robustness. The preference would be to use SynthoCam systems where required due to the inherent integration required for these systems with other Synthotech equipment. The outline performance specification for the CCTV Inspection system is detailed below; 1. 2. 3. 4. 5. 6. 7. 8.
Standardisation where possible with existing CCTV systems Full circumferential vision in 18” to 48” metallic main diameter pipes Have full Pan and Tilt capabilities Able to operate within Natural Gas Able to illuminate the full working environment Function at 200 metres from the access location Able to operate at 2 Bar external pressure To be able to survey pre and post remediation
The capabilities of the most applicable technologies from this section of the report are highlighted below. This section is based upon the host system capabilities as camera systems are all very similar in their standalone performance therefore deriving conclusions is less meaningful.
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Final Project Report Outline Performance Specification
In-pipe Platform CISBOT (6"12")
CISBOT (16"36")
SynthoTrax
Mainspray
Inspector Systems
1
U/N
U/N
Yes
No
U/N
2
No
U/N
Yes
No
U/N
3
No
No
Yes
No
Yes
4
Yes
Yes
Yes
Yes
U/N
5
U/N
U/N
Yes
No
U/N
6
No
No
Yes
No
Yes
7
Yes
Yes
Yes
Yes
U/N
8
Yes
Yes
Yes
No
U/N
Figure 43 – in-pipe platform comparison Discussion / Conclusion High picture quality, particularly for larger diameter pipelines is essential. It is considered that the camera must be able to provide clear detail of the complete internal joint which necessitates the use of a pan and tilt system. Pearpoint do not currently offer a pan and tilt camera for the gas industry. The Synthotech Pan and Tilt camera also has the advantage of being modular and can be connected to a push rod system as well as a robotic platform and has a smaller outer diameter compared to other cameras. Due to the complex nature of the task at hand custom vision systems may be required. These systems could then be specifically targeted where detailed vision is required, for example joint evaluation and tool location. Synthotech have delivered many task specific CCTV devices based upon a proven architecture. Recommendation The recommendation here would be to use the native camera options available based upon sub-system used elsewhere within the device. Should a development activity follow this project then task specific camera systems should be implemented within the complete device.
2.6 External Support Systems There are several additional sub-systems that are required to relay information to the user, control the in-pipe systems and provide power and sealant. The external support systems required are;
Robotic control interface Sealant pumping system Coiler system for robotic tether Ancillary equipment
The current SynthoCam CCI could be used to both relay CCTV and provide robotic control. Additional systems would need to be developed to relay sealant, pneumatic power and control to the in-pipe device. There are many examples of sealant delivery systems in Mainspray, CISBot and in the Synthotech water extraction system. This system needs to verify the volume of sealant that is delivered to each joint, and have a variable application pressure. The coiler system is used to house the robotic tether; there are several examples of systems that range in complexity from push rods to complex internal robotic systems that relay several fluids (Sealant and Pneumatics etc). The coiler systems that are used with these systems can also be upgraded to allow multiple
41
Final Project Report fluids to be accommodated for with larger -multiport swivel fittings. This would allow for increased pneumatic and sealant delivery capabilities. Ancillary equipment that would be required would include;
Tether running seals and spares Associated tooling Running Seal lubricant Additional system specific consumables
The main development within this section would be the electronic control and monitoring of the sealant delivery. This would likely be completed by a solenoid actuated pneumatic directional control valve or through the use of i.e. a peristaltic pump.
2.7 Synthotech ISP From the previous sections it has been shown that no single device is capable of meeting the outline performance specifications. In light of this the following section of the report highlights the Synthotech development concept to meet the outlined performance Specification. The Synthotech ISP concept is to utilize, where viable, the SynthoTrax live internal CCTV Robotic architecture. This system is capable of application distances up to around 200m from a single excavation. This system is currently readily used in the inspection of bell and spigot joints within mains from 18" to 48" (Tier 3) especially to ensure that such joints have been fitted with an additional internal mechanical seals. Synthotech have previously developed additional 'add-on' capabilities for the robotic platform including a laser based profiling device and an actuated Pan and Tilt Inspection system. As a part of this feasibility Synthotech have confirmed the capability of a SynthoTrax based Platform to drill holes into 8" cast Iron metallic mains. The concept has been proven that the system can currently be used to accurately locate and drill holes into the yarn of 8" mains (Fig. 54 - 57). Pipeline Access The ISP concept proposes three methodologies for gaining pipeline access. The methodologies maintain a low requirement for excavation, traffic management and reinstatement. ALH System III and Base
SynthoTrax Access System
ALH System III Valve and Base
36” main
Figure 44 – SynthoTrax Access into an ALH System 3 Base on a 36” medium pressure main
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Final Project Report Permanent – Valve Access
SynthoTrax Access System
AVK Valve and encirclement clamp
18” main Figure 45 – SynthoTrax access into an 18” metallic Main through an encirclement clamp and valve Bond and Bolt Bond & Bolt is a new access methodology currently under development and trial with National Grid and ALH systems. Bond & Bolt can gain access to large diameter mains using a ALH system III valve with an excavation that only uncovers the top of the main.
SynthoTrax access system
ALH System III Valve
Bond & Bolt access fitting
48” main
Figure 46 – SynthoTrax access into a 48” metallic main using bond and bolt
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Final Project Report In-pipe Robotics Platform SynthoTrax The SynthoTrax Robotic Platform is a free weight tracked robotic system. This platform could be used to house a directional spraying system within mains from 18" to 48".
Figure 47 – SynthoTrax in-pipe platforms Tier III Concept (The Beam) One of the major technical challenges of complex in-pipe working is access. Highly functional in pipe devices generally require an increased access bore size. With increased cost associated with larger excavations, specialist teams and higher component cost etc gaining access via standard holistic and temporary access fittings is highly beneficial. 'The Beam' is a Synthotech robotic platform concept that address the issues of maximising the in-pipe space envelope, rigidity & tractive capacity in a package that can be launched into Tier III pipelines through a 6" access bore. The system is based around an expanding wall press system and directional control wheels. The system will be capable of locomotion laterally along the pipe as well as rotation around the circumference of the pipeline. The system could be developed modularly to access pipes from 18" - 48" using 'swap-out' components.
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Final Project Report Push Guide methodology It was mentioned previously that there could be a passively driven vehicle using a guide wire. This system is not traditionally used in the UK, and is only really used on dead pipes. However, where a section of main is long and straight, there is no reason why a push/guide system under live gas conditions could not be considered to ensure that the minimal excavations are utilised.
Figure 48 – push-pull methodology
Sealant Deliver System Synthotech currently have a prototype system that is primarily for the removal of water from pipelines at pressures of up to 5 Bar. This system is push Rod based, uses a camera to detect any local water and a Pump/separator combination to withdraw the water through the Push Rod. This system has the capacity to pump into pipelines rather than pump out. The system allows for monitoring and modification of application pressure and could be used to monitor sealant delivery per joint. There are three options available for the delivery of anaerobic sealant to the cast joints; These methods vary in complexity and potential control of sealant application as ordered above. 1. Directional Spraying 2. Contact spraying/Injection 3. Drilled Injection
Directional Spraying system A Development project could yield a 'Bolt- on' Sealant sub-assembly for the current SynthoTrax robotic platform. This system could use a combination of laser targets and CCTV system to control and direct a jet of sealant accurately to the full circumferential cleft of a bell and spigot joint. The system could be based on a single direction controllable jet of sealant or be based around a rotating dual spray head that targets a set circumferential zone. A directional spraying system would have the advantages that; No drillings required to inject sealant As a result there would be a possible increase in joints per hour
45
Final Project Report Less specific design methodology means potential additional uses Directed fitting spraying (Top Tees etc) Potential to spray any cracks found on inspection before any other remediation work is under taken Sealant application where drilling is not possible Potential reduction to sealant waste vs blind uncontrolled sealant application To accomplish this there would be several deliverables;
Dual cable access glanding Modified methodology Modular telescopic Sealant spray system Sealant Pump and Control unit Modified SynthoTrax Control Interface Spray guards
Contact Spraying / Injection system A system could be developed that applied sealant to the cast joint through contact with the cleft of the joint. This system would have to access the joint at included locations to avoid debris that can normally fill the bottom of the main and the cleft of the cast iron mains joints. This system would press a elastomeric sealing face into the joint cleft and direct the injection of anaerobic sealant into the joint. For larger mains it may be necessary to apply sealant in more than one location to guarantee a quality seal. To accomplish this in the largest mains the standard SynthoTrax platform would need further redevelopment. A contact spraying / Injection system would have the advantages that;
No drillings required to inject sealant As a result there would be a possible increase in joints per hour Sealant application where drilling is not possible Increased Sealant application pressure at joint interface may mean better impregnation vs. spraying techniques Potential reduction to sealant waste vs. spraying techniques To accomplish this a there would be several deliverables;
Bespoke in-pipe platform Semi ridged Tool mountings. Dual cable access glanding / Multi-Core tether Modified methodology Telescopic contact sealant injection system Sealant Pump and Control unit Modified SynthoTrax Control Interface Spray guards
A point contact system may also be capable, with further development to apply an additional viscous sealant bead into the cleft of the Spigot Joint. To accomplish this; the Beam concept platform would be required. The system would be required to clean the cleft of the joint to ensure adhesion of approved sealants. Drilled Injection system A system could be developed that applied sealant to the cast joint through a hole drilled into the cast iron joint. For larger mains, it may be necessary to apply sealant in more than one location to guarantee a quality seal. To accomplish this in the largest mains the standard SynthoTrax platform would need significant redevelopment.
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Final Project Report The main limiting factor within this development activity would be the restricted access bore of 6" needed to utilize holistic access methodologies. To address this issue use of the Tier III concept in pipe platform is proposed. A Drilled Injection system would have the advantages that; Increased Sealant application pressure at drilled interface may mean better impregnation vs. spraying and point contact techniques Potential reduction to sealant waste vs. spraying and point contact techniques To accomplish this there would be several deliverables;
Bespoke in-pipe platform Modular Circumferential Drilling system Modular Circumferential Injection System Ridged Tool mountings. Dual cable access glanding / Multi-Core tether Modified methodology Telescopic Drill and Sealant Injection System Sealant Pump and Control unit Modified SynthoTrax Control Interface
Technical Considerations. Tether Cable The tether cable supplies the in-pipe system with all resources required. The cable(s) for use within this system will be required to deliver;
Electronic power Electronic control Data Relay (CCTV video, closed loop control data) Pneumatic power (compressed nitrogen) Hydraulic power / Sealant
The cable needs to remain as lightweight as possible to ensure the maximum application distance. The design limitations that maximising application distance causes are; slower sealant application slower Pneumatic Response low vehicle Speed In order to deliver all of the in-pipe requirements it is likely that a custom tether cable will be required. This cable will be comprised of;
Power Transmission Live Twisted Pair Data lines Sealant Delivery Lines x2 (contingency) Pneumatic Feed lines x 4: Drill actuation Wall Press Actuation Sealant Application mechanism Contingency Line Pneumatic Return line (larger Bore than above) PU sheath Aramid Strain core ( emergency retrieval) 47
Final Project Report The cable can be assembled as an umbilical, a multi tether or a complete moulded solution. A complete moulded solution would offer the most ergonomic application process especially when compared to a multi tether option where multiple glands are needed and tangling of the cable can become a high risk over elevated distances. Electronics The current SynthoTrax tether system has the capacity for 2x 48 volt power lines and 3x twisted pairs that are used for control and data relay. The SynthoTrax control architecture uses a RS-485 protocol for control data transmission. Bi-directional motor control is gained using 4 pin outs from the PIC in combination with solid state relays (nonmechanical) in a 'H' Bridge configuration. This architecture can be up rated and expanded to increase the number of controllable systems as well as the running power and voltage for larger systems. Sealant Delivery The delivery of sealant would depend upon several variables, these would include;
sealant viscosity pipeline size (Required sealant) delivery tube length / application distance in-pipe delivery tube temperature sealant output pressure (controllable) Required joint injection pressure
Delivery Pressure Methodology There are two main methodologies for sealant injection, direct pumping and passive pumping. In active pumping, the sealant would be passed directly through a pump (i.e. a Peristaltic pump), In passive pumping an increased pneumatic pressure is used to apply the sealant (i.e. water accumulator). Both methods have very similar operating pressures, flow rates, and can easily be used to measure flow of the sealant
Figure 48a – Push-sealant pumping methods. Pneumatic & Hydraulic Transfer The hydraulic, pneumatic and sealant delivery transfer lines within the tether will cause a pressure difference between the pump and the in-pipe platform. 'Pipe friction' is calculated using the Darcy-Weisbach equation shown below. 𝐻= 𝜆
48
𝑙𝑣 2 ∆𝑃 = 𝑑2𝑔 𝜌𝑔
Final Project Report In this equation 𝜆 (lambda) is the friction of coefficient for the pipe. This can be determined experimentally and is expressed in Moody diagrams, (Fig.) and curve-fitting equations that approximately describe these data sets, these approximations are normally accurate to around 10%.
Figure 48b – friction factors graphs
Using the Darcy-Weisbach equation in combination with experimental curve fitting equations to iterate a solution to the friction factor, the pressure drops across a length of pipe can be found. These results are tabulated below to show pressure drops within the size range of the project. (Note the Log scale)
Figure 48c – pressure drop graph The graph shows that the hydraulic lines generate a significant pressure loss at the flow speeds highlighted (between 1Bar and 100Bar) where as the air-lines offer a vastly reduced loss, highlighting the capacity for actuation over distance. A more subtle insight is the diminishing benefit to larger tubing sizes. This is highlighted by the reducing difference in pressure loss with respect to tubing increasing size. When this is compared to the weight increase of the tether due to larger tubing (weight increases as a factor of the square of tubing radius, based on sealant weight) oversized tubing offers a reduced benefit and a significantly increased weight. To increase the pressure available for injection into the joints, pump pressure can be increased; additionally a flow-restricting orifice at the injection point would reduce the flow rate and speed consequently boosting the pressure.
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Final Project Report
Figure 48d – flow speed graph Fundamentally, the slower that sealant can be injected into the joints offers benefits in terms of reduced tether weight and therefore increased application distances. Even within the higher end of the range considered it can be seen that sealant injection is feasible over 200m. The remaining variables to this conclusion are pump outlet pressure, application pressure and the time required per joint. Power transmission and actuation can typically be achieved either electronically, mechanically, hydraulically or pneumatically. Whilst mechanical systems can be more efficient, they are not well suited to this project. A comparison of the remaining methodologies is included below.
Electrical
Hydraulic
Energy source
Usually from an external source
Electric motor or diesel driven
Electric motor or diesel driven
Energy storage
Limited (batteries)
Limited (accumulator)
Good (reservoir)
Distribution system
Excellent, with minimal loss
Limited basically a local facility
Good Can be treated as a plant wide service
Energy cost
Lowest
Medium
Highest
Rotary actuators
AC and DC motors Good control on DC motors AC motors cheap
Low speed Good control Can be stalled
Wide speed range Accurate speed control difficult
Linear actuator
Short motion via solenoid Otherwise via mechanical conversion
Cylinders Very high force
Cylinders Medium force
Controllable force
Possible with solenoid and DC motors Complicated by need for cooling
Controllable high force
Controllable medium force
Points to note
Danger from electric shock
Leakage dangerous and unsightly, Fire hazard
Noise
Figure 48e – Actuation comparison table
50
Pneumatic
Final Project Report For use within a development, the requirements of the system must first be known to allow the most suitable choice to be made. Generally, electronic systems, most notably motors integrate into most situations well and offer a high degree of controllability. However, in situations where linear actuation, increased force, or stalling capacity is required these systems are not optimal. For use within this system, a combination of electronics and pneumatics would offer the most flexible solution. Pneumatics in this case has several advantages over a hydraulic system, these are; Reduced tether weight (gas is less dense than hydraulic fluid resulting in greater range due to a reduced tether cable drag force) Reduced viscosity (offers increased range with less pressure drop and greater flow rates for increased operational speed) leaks are much less messy 'Softer' response offers increased flexibility within the environment (suspension) Gas can be easily stored and regulated (Compressed nitrogen) Actuators can be very small (allows integration onto the in-pipe device) Pneumatic systems can be controlled and monitored electronically offering additional benefits in terms of performance and systems ergonomics. I/P (current to pressure converters) and analogue controllers (such as joysticks) would offer a highly user controllable system where required. Additionally with electronic closed loop control, these systems can be made repeatable, traceable and automated to meet best-case performance. Sealant Reactivity The anaerobic sealant used to seal the lead yarn joints contains several chemicals that can affect certain materials. The main constituents of Mainspray are;
1. 2-ethylhexyl methacrylate
2. Hydroxy Propyl Methacrylate
3. Cumene Hydroperoxide
2-ethylhexyl methacrylate is the main constituent of Mainspray; it is a methacrylate ester and will dissolve Perspex and cause stress cracking in many other plastics and rubbers. Additionally this compound can cause swelling of some rubbers used in standard o-rings. Usually polymers containing nitrile groups tend to have good solvent resistance and are therefore less susceptible to solvents than metacrylate based materials (like Perspex). However even within the grouping of nitrile-based polymers it is likely that some materials will offer superior resistance. Determining the effects of Mainspray on any elastomers and polymers used within the construction of the final device will inevitably be a method of trial and error based upon logical material selection. There is data
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Final Project Report available that lists the compatibility of construction materials and certain chemicals, however due to the immense number of compounds and mixtures specific data is not readily available. Robotic Platform Free Weight vs. Wall Press Limited traction is available using the free body weight of an in-pipe device. A wall press device has the advantage that large gains in traction are feasible. The main drawback to such systems is complexity, especially as in this instance where the difference between the access hole cross sectional area (6" BSP tapping) and working cross sectional area (48" main) is so large. Traction is the maximum force that can be generated on the running wheels without slippage; this is denoted in a similar way to resistive friction, for example; 𝐹 = 𝜇𝑀𝑔 With a limited space envelope and considering the practicalities of an ergonomic device, free weight traction is limited and less adaptable. A pneumatically actuated wall press system offers the advantage of a variable potential tractive force that is controlled though actuator pressure. i.e. 𝐹 = 𝜇𝑀𝑔 + 𝜇 ∑ 𝑅
An additional benefit of pneumatics in this instance is the spring like basis. There are additional factors that can influence the available traction. Within the likely conditions these could include; Contaminants (Sealant, weasel, water and grit will lubricate the contact patch and reduce traction) Contact shape and material ( material choice can dramatically effect 𝜇 value and shape will in part determine wear rate ) Relative surface motions ( incorrect wheel alignment will 'waste' traction through inefficiencies ) Adopting the theory of a four point wheel contact then;
Figure 48f – pipe traction graph An increasing number of wheels can be used to reduce the reaction force at each of the contact patches (area where the wheel(s) meet the running surface) whilst maintain the total available traction. This is effectively distributing the load over a wider area. This may be important to both increase the total tractive effort and minimise loading upon the cast mains to within acceptable limits. Traction is unaffected by the size of the contact patch; both small and large contact areas offer the same traction whilst reaction force and friction coefficients remain the same. The available traction can however be 52
Final Project Report increased using a material with a higher coefficient of friction - these materials generally have a greater rate of wear. In these cases, a greater contact patch is used to spread the wear over a larger area and increase wheel life. The loading caused by the wall press device should be considered in terms of worst case scenario within the pipe range. A load case must be explored to include;
Minimum expected Cast Main wall thickness Average Minimum material strength Reduction in strength due to access hole (@ D/3) Reduction in strength due to internal and external pitting Pipeline loading through depth of cover and hydrostatic head Internal pipeline pressure Secondary loading from road traffic etc Safety factor
For the purposes of this feasibility study an initial investigation was conducted with the following specifications; Property
Value
Material Modulus
6.61x1010 Pa
Compressive Strength
572 MPa
Tensile Strength
151 MPa*
Access hole size
6" BSP
External load through top cover
20,000 Pa
Internal Pressure
2 Bar
Secondary Loading (Surcharge Pressure)
45,000 Pa
Pipeline Size
18" (B.S. 78 : 1938)
Wall Thickness
.63" (16.002mm)
Simulated Beam Span
3m
*tensile strength taken as material limit doe to lower value and brittle failure characteristics The results computed consisted of a fixed beam support, maximum tapping size and both full radial/top loading. The results of these studies are shown in Figure 48g.
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Final Project Report
Figure 48g – Pipeline loading plot
The initial results showed a maximum stress of around 40MPa, compared with the Tensile strength of 151MPa there is sufficient capacity for additional loading. This study has however omitted several important factors including corrosion pits. These pits would lower the overall material strength as well as acting as local stress riser. These could contribute to brittle failure under certain circumstances. (Deformations above are greatly exaggerated) Assuming four contact loads of the in-pipe device of 30Kg a total additional load of ~1200N would act upon the pipeline. This is not comparable to the total external loading of the pipe that is in this example of around 300,000N. During any developmental work, these models will need to be revised in accordance with the project parameters. Further work on validating and verifying these simulations must be undertaken to ensure accuracy. Suspension The variable in-pipe environment can pose severe problems for rigid wall press systems. Such systems would not be able to maintain a reaction with the pipe wall where local changes in diameter are encountered. For this reason hydraulic or electronic wall press actuation systems would not be adequate alone and would require a form of suspension. If this was not implemented there would likely be a significant loss in possible application distances and a reliance on free weight traction. A suspension system would allow the in-pipe platform to maintain traction whilst maximising flexibility. A suspension system could be based around springs or pneumatic cylinders. It would be recommended that the system utilise pneumatic rams as the application pressure could possibly be used for both the actuation and suspension of the wall press system offering a dual purpose and increased efficiency. Wheel systems There are several methodologies that can be implemented for pipeline contact. These methods are described below in the table with comparisons:
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Final Project Report Methodology Load Distribution Complexity DoF
Tracked
Standard wheel
Power castors
Omni wheels
Omni Tracks
Good
Poor
Poor
Poor
Good
low
low
high
Low
high
2
2
3
3
3
2
2
3
2
2
medium
low
low
medium
high
high
low
high
low
high
(Degrees of freedom) DoA (Degrees of actuation) Potential for Ingress Space Requirements
Figure 48h – wheel system comparison. Tracked wheel systems offer the best distribution of load within the pipeline, they also offer the highest potential coefficients of friction due to the large area available for wear. These systems are more complicated to implement due to the addition design constraints that they impose, including dirt ingress, belt tension and suspension requirements. Tracked systems also require a great amount of space and thus would be more difficult to implement within the space constraints introduced by the access bore. A standard tracked system would not be capable of in-pipe rotation and longitudinal travel; however a tracked Omni wheel system would be able to meet this requirement. In-pipe rotation means better in pipe rigidity and better control. Tracked Omni wheel systems have a low efficiency because of the misalignment of driving direction necessary to generate the 'free' DoF. This free DoF does however mean that there are fewer requirements for actuation that reduces mechanical complexity and increases performance in many areas (i.e. space envelope and cable weight).
Figure 48i – a Mecanum and an Omni wheel
Standard wheel systems would require two full sets of wheel aligned in both directions of travel. These wheel sets would also require additional actuation to break contact with the pipeline wall to allow free travel in both directions. A power castor system would allow for travel in any combination of longitudinal and circumferential directions and would represent the most versatile system. However to make the most of this system the alignment of each wheel station should be monitored in a closed loop. Wall press application pressure should be dropped where stationary turns are made to avoid wear and damage to the wheels (this would be best practice for both Omni wheels and Omni tacks also).
55
Final Project Report A power castor system could offer a more controllable system with less computational requirements but the mechanical complexity would be high due to the limited space envelope. Omni wheels or Mecanum would offer a more mechanically simple system but accurate rotational control would be difficult - especially considering the uneven, high friction nature of the pipeline surface. There would be additional sensing, computation and control requirements for Omni wheel systems vs. a power castor. Wheel Torque Electric motors are unable to be stalled without being damaged. If electric motors are used to provide wheel torque and locomotion then counter measures against stalling are required. To accomplish this either a current limiting circuit is required to stop burnout of the motors at slow speed, or, the system is designed so that at maximum traction the motors are able to spin the wheels freely as per the following example with approximate values; 𝑓𝑚𝑤 = 𝜇𝑚𝑤 𝑅 < 𝜇𝑚𝑐 𝑀𝑐𝑎𝑏𝑙𝑒 𝑔 <
(0.8)30(9.81) = 235.44 <
𝑇𝑚𝑤 𝑟 𝑤
1000𝑁 𝑇𝑚𝑤 < 4 (0.035)
Which would give; 𝑇𝑚𝑤 > 250(0.035) = 8.75𝑁𝑚 8.75Nm would therefore represent the working continuous working output torque of four drive motors. This would provide a towing limit of 1000N without stall with an available traction of 235.44N per wheel. The current SynthoTrax system uses two 48v motors that can deliver continuous output of 4.5Nm. These motors can be geared together to increase the torque output. Additionally there are various gearing options available for the motors planetary gearing. This means that multiple motors with lower gear ratios (individually producing less torque) could be used to give both increased total torque and greater speed. The disadvantage to increasing the platform driving torque and speed is power. The increased current draw will require thicker heavier power cables. Additionally where power is used in a non-constant manor (i.e. AC signal) induction across the power and data transfer lines may result in additional electrical interference. Sensors & control Historically CCTV camera systems allow for the capture of purely qualitative data relating to the in-pipe environment. CCTV systems can be computationally manipulated and used to gain some quantitative data, for example laser profiling and optical measurement systems. To gain additional in-pipe intelligence there are a multitude of additional transducers systems that can give further information. These may include;
Level / Tilt sensors Acoustic sensors Ultra sonic wall thickness Positional sensors Load sensors gas sensors (i.e. methane / oxygen) A benefit of additional transducers is that they allow for closed loop control. In a closed loop system the output is monitored and alterations made to the input to ensure that the output is within a determine range. Some examples are given below.
In the instance of in-pipe robotics, these examples can be misleading as the driver of a car forms a control loop when turning on/off the wipers or using the throttle. Where actuation is used within a remote 56
Final Project Report environment feedback is critical to ensure an output. This is normally achieved via the use of camera system to, for example, ensure that an in-pipe device is travelling or that an internal drilling system is cutting the pipe material.
Figure 48j – closed loop control companions
Where internal CCTV systems cannot be used to gain confidence that, the 'output' is as required closed loop control is a necessity. The most notable case of this, within this project, is the injection of sealant into a joint. This is because this cannot be verified optically using in-pipe inspection techniques. Closed loop control has many benefits over open loop systems, however has additional cost, complexity and space requirements. For these reasons it is critical to ensure that closed loop control is only used where open loop system would not suffice. Hole Drilling Cast Iron Cast Iron is a name given to a range higher carbon cast materials, these can be unalloyed, low alloyed or highly alloyed. Cast Irons generally contain around 0.8-3% Silicon and 2-5% carbon, generally in the form of Graphite. The microstructure of the material can be either Ferrite, Pearilte or a combination of the two. Grey Cast Iron contains large flakes that give an acoustic dampening effect and a low rate of wear. Drilling Cast Iron is typically a free machining and self-lubricating material (Predominantly due to the high graphite content). Cast Iron age hardens and can reach a hardness of around 200 Birnell. When drilling Cast Iron a high feed (Drill pressure) and relatively low rotational speed are used. The use of coolant/lubricants is not recommended as it can combine with the material swarf and form an abrasive paste that acts to clog instruments. A Carbide tipped drill bit would offer the best solution for the cutter. This has the benefit of a High hardness tip that offers a low wear rate and a flexible shaft that can tolerate snagging without fracture (Compared to solid Carbide). Cast Iron Swarf Swarf produced from the drilling of Cast Iron is hard and fine. In general, Cast Iron swarf can damage sliding tool components where it acts as an abrasive power. Care must be taken to ensure that vulnerable areas of the in-pipe platform are adequately protected from this swarf. Drill location control system rigidity The drill system requires significant rigidity to drill a hole accurately and efficiently. This can be achieved to a limited degree without a wall press system in smaller mains but would be exponentially more complex in larger mains. Some flexibility is required within the drill system to allow minor movement of the drill along the pipe surface. The pitted internal surface of the Cast Iron may bend the drill into a pit on application. Drilling with a bent drill will eventually lead to failure though crack propagation within the drill shaft. Depth control The simplest methodology for depth control would be an adjustable stop. The stop would be set according to the size and thickness of the main and allow for drilling into the yarn only and not through the bell of the joint. The drill system must have a reversible rotation to aid in the retrieval of the drill bit.
57
Final Project Report Leakage Detection Over the last few years, there have been great steps forward in the development of acoustic leak detection systems for water and sewage systems. There is currently a great deal of interest in the development of leakage detection within the gas industry, in particular driven by the OFGEM RIIO requirements. The main system that is already claiming that it is able to detect leaks within live gas pipes is the JD7 point location system. Other systems that have received wider acclaim and are currently investigating the possibility of transferring over to the gas industry are the Acoustek and the SewerBat Systems. As part of any final design, consideration should be included into the possibility of including such a device. Sealant Development Risk Matrix
Controlled Spray
2
3
2
12
2
Contact Spray
4
4
3
48
3
Drilled Injection
4
5
4
80
Risk
Developme nt (D)
1
Likelihood (L)
Technology (T)
Description
Item / Note
Method
Risk = T X D X L Figure 49 – Sealant application risk matrix
2.8 Report Conclusion and Recommendations This report has focused on providing possible solutions to the scope, broken into the following sections; 1. 2. 3. 4. 5. 6.
Access Fitting Access System In-pipe platform Sealant Application system In-pipe CCTV External Support Systems
For each section, there has been a recommendation and or a developmental requirement. It has been highlighted that Synthotech Innovative Engineering supply CCTV and robotic equipment, and that the recommendations within this report have reviewed multiple product suppliers. Where development as discussed they are focused on the existing Synthotech Innovative Engineering range of CCTV systems and existing robotics architectures. An existing solution and possible solution are believed to be available from UCL Robotics in North America. Where appropriate the known information about the CISBOT ULC Robotics product has been included for referenced. SGN are in discussion with UCL Robotics concerning their CISBOT product range. This report has shown that there are feasible, developmental solutions available that can meet the elements of the complete performance specification. The report has highlighted the requirements of three such devices that could meet the requirements in their entirety, based on three sealing methodologies; 1. Directional spraying 58
Final Project Report 2. Contact injection 3. Drilled Injection These methodologies are listed in increasing complexity. Development and testing work is required to determine the effectiveness and suitability of each approach. Due to the relative simplicity of directional spraying (option 1) & the similarity of contact injection and drilled injection (options 2 & 3), it is initially anticipated that these developments could be completed (if required) within the originally proposed timeline by applying additional resource to the project. Current sealant methods used externally generally use thicker anaerobic leakage sealants. The ULC Robotics CISBOT product uses the same methodology and sealant (Chemence Anacure) internally. The Mainspray product used within the UK and overseas markets also has the capability to seal by just directionally spraying and ‘wetting’ the yarn. This has a proven track record and a full UK approval. The simplicity of spraying the sealant rather than having to drill and inject means a significantly faster and more cost effective development. If a more focused contact injection or drilled injection is required, then the complexity of the propulsion (locomotion) system and sealant delivery system increases significantly - requiring more resources to complete. To highlight the development programme a brief outline of what developmental actives are required is detailed below.
Colour
Development Activity In-pipe Locomotion system Access System Sealant Delivery System Drilling System External Support Systems Figure 49a – development flowchart
59
Final Project Report Feasibility Recommendations It is recommended that SynthoTrax ISP is developed with all three sealant methodologies up to producing preliminary working designs. The most suitable system should then be selected for the complete system in line with the Scotia Gas Networks requirements.
A
B
C
Figure 50 – Spraying system (A), point contact injection (B) and drilled injection (C)
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Final Project Report
Feasibility Risk Matrix Before the feasibility study work was started, a Feasibility Risk Matrix was derived on the information that had been gathered for the initial proposal. As part of the end process of the feasibility study, the Feasibility Risk Matrix was completed again. As can be seen by Figure 57 the risk of the project has been reduced from a risk level of 200 to 55.
Risk
Likelihood (L)
Development (D)
Technology (T)
1
Access Fitting
2
2
3
12
1
1
1
1
2
Access System
3
3
2
18
2
2
2
8
3
In-pipe Platform
3
5
4
60
2
3
2
12
4
Sealant Injection System
4
5
4
80
2
4
3
24
5
CCTV Inspection
2
3
1
6
1
2
1
2
6
External Support Systems
3
4
2
24
2
2
2
8
Risk = T X D X L
33
9
Figure 51. Feasibility Risk Matrix
Key Technology
1 = Existing Technology
5 = New Technology
Development
1 = Low Development
5 = Higher Development
Likelihood
1 = Likely
5 - Unlikely
61
After Feasibility
Risk
(L)
Likelihood
Development (D)
Technology (T)
Description
Item / Note
Before Feasibility
Item 1 – Access fittings to based around ALH System III valve Item 2 – Access system to be re-developed in line with project objectives based on the standards SynthoTrax methodology Item 3 – Development of the SynthoTrax based device Item 4 – the development of a Sealant application system (spray based) Item 5 – CCTV system to be an existing product with possible development/modification for use with the device Item 6 – Synthotech feel that this project is possible and in line with previous developments undertaken
Final Project Report
Figure 52 – feasibility risk assessment
62
Final Project Report Concept Trialling
Figure 53 – SynthoTrax platform with a concept drilling rig inside an 8” cast iron main
Figure 54 – SynthoTrax ISP concept drilling into a cast iron joint
Figure 55 – Reverse view of SynthoTrax ISP concept drilling into a cast iron joint.
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Final Project Report
Figure 56 – SynthoTrax ISP concept drill being removed from a cast iron joint, after drilling
Figure 57 – SynthoTrax ISP concept drilled hole next to joint line
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Final Project Report
Appendix A - Glossary of Terms CCD
Charge Coupled Device
CCTV
Close Circuit Television
CH4
Methane
EN
European Number Standard
GIS
Gas Industry Standard
HDPE
High density Polyethylene
ISO
International Standard Organisation
Km
Kilometre
NDE
Non destructive examination
NDT
Non destructive testing
PE
Polyethylene
SL
Synthotech Limited
GMO
General Motor Oil
MEK
Methyl ethyl ketone
SGN
Scotia Gas Networks
ISP
I-Seal Process
OFGEM
Office of Gas and Electricity Markets
RIIO
Revenue = Incentives + Innovation + Outputs
Tier I
3" - 8" Mains
Tier II
10" - 16" Mains
Tier III
18" - 48" Mains
30/30
Mains Replacement Programme
SynthoTrax Platform
Refers to the Base robotic in pipe with only locomotion capabilities
SynthoTrax Architecture
Refers to the power, control and actuation systems and methodology of the SynthoTrax platform
CCI
Crawler Control Interface
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Final Project Report
Appendix B - Development Specification Development of 2 bar specification – SynthoTrax ISP Mandatory and non-mandatory requirements For the purposes of this Synthotech Gas Standard, the following auxiliary verbs have the meanings indicated: Can
indicates a physical possibility;
May
indicates an option that is not mandatory;
Shall
indicates a GIS requirement;
Should
indicates best practice and is the preferred option. If an alternative method is used then a suitable and sufficient risk assessment needs to be completed to show that the alternative method delivers the same, or better, level of protection.
Disclaimer This engineering document is provided by Synthotech Limited for review as part of a development project. Any equipment that complies with this engineering document does not mean compliance with any gas transporters specifications. Where this engineering document is used by any other party, it is the responsibility of that party to ensure that the engineering document is correctly applied, including authorisation by the appropriate Gas Transporter. Brief history First published as SL/D22/SGS/01 January 2013 © Synthotech Limited, on behalf of Scotia Gas Networks. This Synthotech Gas Standard is copyright and must not be reproduced in whole or in part by any means without the approval in writing of either Synthotech Limited or Scotia Gas Networks. 1 Scope This Synthotech Gas Standard specifies requirements for SynthoTrax ISP equipment for large diameter gas main internal joint remediation remotely operated through small access and egress points. This device is for use at pressures up to and including 2bar for insertion up to 200metres in a single direction. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. Formal standards BS EN 682:2002, Elastomeric seals — Materials requirements for seals used in pipes and fittings carrying gas and hydrocarbon fluids. Gas Industry Standards GIS/E48, Specification for polyethylene service line tracing equipment. 3 Terms and definitions For the purposes of this standard the following terms and definitions apply. 3.1 SynthoTrax ISP
66
Final Project Report The complete system for insertion of a robotic device under live gas conditions, that is capable of remediating a joint via the application of a leakage sealant. 3.2 SynthoTrax ISP Vehicle The Robotic motorised device that will access into the pipe through a small access hole, drive along a pipe identifying joints, accessing the joint and injecting an appropriate leakage sealant to stop any gas sealant. 3.2 Access Fitting This is the access fitting on the gas main, whether it is end on insertion, or vertical insertion through a permanent access valve or a temporary access valve 3.3 Glanding System This is the system that encompasses SynthoTrax ISP during insertion, operation and removal, limiting and thus controlling 3.4 Insertion Coiler This is the tethered power and communication umbilical between the SynthoTrax ISP Vehicle and the Control Unit 3.5 Control Unit The computerised control device that controls the operation of the SynthoTrax ISP Vehicle 3.6 Leakage Sealant The leakage sealant that is used as the fluid medium for application into a metallic joint to prevent the joint from leaking 3.7 ISP System The system by which the Leakage Sealant is applied to remediate the joint. 4 Application The SynthoTrax ISP System It shall be possible to use the equipment on mains operating at pressures up to a maximum of 2 bar. It shall be able to enter the gas supply under “live gas” conditions via a suitable fixed valve, applied valve or temporary valve that are used by the Gas Transporter with minimal or no release of gas. The equipment shall be able to be maintained on at least a 12 monthly basis. It shall be compatible with the current range of leakage sealants. It shall be small enough to enter a 160mm diameter hole to enable entry into the existing metallic pipe work. It shall be manoeuvrable enough to be able to cope with insertion around 90° bends in the pipe range of 18” to 48”. It shall be able to provide accuracy of detection of a joint, and allow joint remediation under live gas conditions. It shall be capable of use at a distance of 200 m from the insertion point. 4 Strength The equipment shall be designed and constructed to ensure it is robust enough to withstand everyday usage, which may include use in excavations and building sites. It shall also be designed and constructed, so that its operation is unaffected by site conditions such as contamination by mud or water. As the equipment will be used outside in potentially wet conditions, i.e. rain, it shall be sufficiently waterproof to allow normal operation under these circumstances. The equipment shall be made from materials which are unlikely to become distorted. 5 Construction and materials All components shall be suitable for use with natural gas. The equipment shall be resistant to petroleum-based products such as oil, petrol and diesel, etc. The access system will be made of a non sparking material and the combination of the parts will be designed to eliminate static. The equipment will be designed to be as 67
Final Project Report lightweight as possible without affecting its operational capability. Where possible the equipment will be 90% recyclable. 6 Design 6.1 The tool shall be capable of being connected to an appropriate main fitting or main access valve (temporary or permanent) to facilitate live access to a low or medium pressure metallic main pipe. It shall be possible to attach and remove the tool without disturbing the main valves or fitting. It shall remain attached to the service fitting under all operating and pressure conditions. 6.2 The tool shall incorporate a shut-off device so that gas can be contained in order to facilitate access to the service fitting, insertion and retraction of the SynthoTrax ISP Vehicle, and subsequent re-commissioning of the main fitting. 6.3 The tool shall be tested to ensure that it is operable and to prevent it from becoming detached from the main fitting under all operating conditions. There shall be provision to proof pressure test the tool, and its attachment, to a service fitting to a pressure of operating pressure prior to exposure to live gas conditions. 6.4 Under static conditions the tool shall be capable of retaining live gas at medium pressure operating conditions, and the pressure drop from the tool shall not exceed 1 mbar over a 1 min period at a test pressure of 2bar. Under operational conditions, including live access to a metallic main and the insertion and retraction of the SynthoTrax ISP vehicle into the metallic main, the pressure drop shall not exceed 10 mbar over a 5 min period at a test pressure of 2bar. 6.5 The tool must be designed to negotiate most obstructions within the gas main while under live conditions. 6.6 The tool must be able to remotely drill into a metallic joint circumferentially at a distance 200metres away from the access point 6.7 The tool must be able to remotely inject a leakage sealant at a distance 200metres away from the access point. 6.8 The gland seal material shall be in accordance with BS EN 682. The equipment shall have no sharp edges or other protrusions that can injure hands, fingers, etc. when in operation. 7 Performance 7.1 Proof test When tested in accordance with Annex A, the pressure drop across the tool shall be no more than 1 mbar over the 30 min period. 7.2 Attachment of the tool to a main fitting 7.2.1 When connected to the main fitting the tool should be tested in accordance with Annex B, and the pressure drop shall be no more than 1mbar over a 5 minute period. NOTE The purpose of this test is to demonstrate that the sealing arrangement between the tool and the Main fitting can adequately contain the maximum operating pressure. 7.2.2 Where there are variations of main fittings that are to be accommodated by the attachment, the set up shall be tested with each type of main fitting. 7.3 Operation 7.3.1 When tested in accordance with Annex C, the pressure drop across the closure seal shall be no more than 5 mbar during the complete operation. 7.3.2 When tested in accordance with D, the pressure drop across the closure gland during insertion and retrieval shall not exceed 5 mbar. 7.4 Tool operation When tested in accordance with Annex D, the SynthoTrax ISP platform will be deployed over 200metres, and remotely driven into position to drill into a joint, to inject a leakage sealant into the drilling. 8 Handling characteristics 68
Final Project Report The equipment shall be designed with suitable handholds to ensure that an operative can securely grip the equipment during use and/or transportation. The equipment shall have no sharp edges or other protrusions that can injure hands, fingers, etc. when lowering, lifting or transporting. 9 Marking Products conforming to SL/D22/SGS/01 shall be permanently marked with the following information: a) the number and date of this standard, i.e. SL/D22/SGS/01); b) the name or trademark of the manufacturer or their appointed agent; c) the manufacturer’s contact details; d) production date; e) model and serial number; 10 Storage The equipment shall be supplied with appropriate carrying cases which shall be capable of securely storing the components when not in use. Thos components not in storage case must be robust enough for self storage. 11 User instructions User instructions shall be provided with each item of equipment. 12 Maintenance The equipment shall have access to internal parts only through use of special tools to help ensure only those persons deemed competent undertake any maintenance activities on the units. Each unit of equipment shall be provided with clear instructions detailing how any fitted batteries and bulbs or any other component can be exchanged or maintained without invalidating product certification. Specification Appendix Annex A – Proof Test Annex B – Attachment Test Annex C – Operation Test Annex D – Robotic Test
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Final Project Report
Appendix C - Development of methodology for SynthoTrax ISP The methodology being used is based on insertion to the furthest possible joint, and sealant operation is being carried out on reversal. Access SynthoTrax ISP Insertion Method (Schematic Simplified for Temporary Valve) 1. Assemble an ALH System 3 Valve onto the main. 2. Drill a 160mm diameter pipe and leave the system with the valve closed. 3. Feed cable through gas seal “burger pack” on the Glanding System Chamber 4. Feed cable through the insertion tube. 6. Screw “burger pack” gas seal to the Insertion tube cap.
7. Attach the cable to SynthoTrax ISP (B). 8. Fix the cable restraint to SynthoTrax ISP crawler. 9. Attach the claw to SynthoTrax ISP (A).
10. Pull SynthoTrax ISP into insertion tube.
11. Attach the completed insertion tube to the gate valve. 12. Connect the Leakage Sealant delivery chambers to the control unit and purge with nitrogen.
70
Final Project Report 13. Open the gate valve and purge air out of the insertion tube. 14. Turn on SynthoTrax ISP 15. Carry out a full functionality test 16. Lower SynthoTrax ISP to the bottom of the pipe. 17. Slowly drive SynthoTrax ISP forwards while continuing to lower the claw down. 18. Release the claw when SynthoTrax ISP has rotated through 90 degrees and is fully in contact with the base of the pipe.
17. Raise the camera to the centre of the pipe and begin the survey
Operation Note: Internal leakage checking before and after by using some form of acoustics or differential pressure. 18. Drive along the pipe confirming all obstacles and carrying out a full survey. 19. Arrive at the last joint, and choose the side view camera. 20. When located at the appropriate point on the joint, the drilling system is rotated round to the correct position. 21. A hole is drilled into the joint 22. The drill is removed and a tap is inserted into the hole 23. The Leakage Sealant injection system is then rotated to the hole, and connected to the thread. The sealant is then primed, and injected until the appropriate backpressure is reached. 24. The Leakage Slant injection system is then removed, leaving the one-way nipple in place. 25. The process is repeated if required circumferentially on the joint. 26. Continue to reverse until you reach the next joint and repeat the above actions.
71
Final Project Report Egress 27. Reverse the SynthoTrax ISP back to the insertion point. 28. Line up the SynthoTrax ISP with the claw 29. Engage and connect the claw to the back of SynthoTrax ISP 30. Drive SynthoTrax ISP backwards, while lifting the claw back into the insertion chamber. 31. When SynthoTrax ISP is fully into the insertion tube, close the valve to the ALH System 3 Valve. 32. Switch off all controls, vent off the chamber and remove from the pipe. 33. Disconnect and strip down the system putting it away. 34. Complete the pipe as per Network Transporters standard operating procedures.
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Final Project Report
Appendix E - I-Seal
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Final Project Report
Appendix F - CCTV Inspection Camera Comparison Pearpoint Systems Pearpoint offer a range of push rod and crawler camera systems to the drainage sector, they offer a CCTV system for use on metallic gas mains. Pearpoint have UK Gas approval for
4” to 8” mains Access via WASK base 25mm Intrinsically Safe Camera 50mm diameter camera Standard crawler system
ECA Hytec ECA Hytec offers a range of crawler and submersible systems for use in specialised markets such as petrochemical, defence and the nuclear industry. They are based in the South of France. They do not have any UK approval but have a Pan and Tilt Explosion Proof Camera. This system would have use in mains up to 48”. Synthotech Systems Synthotech currently supply a range of gas specific CCTV systems for the UK gas market. The systems are designed for 3” to 48” metallic mains and 63mm to 180mm PE pipelines. The systems include push rod systems, pan and tilt systems and motorised robotic systems. Synthotech currently have approvals for
3” to 8” metallic mains 10“ to 24” metallic mains 18” to 48” metallic mains Access via WASK and ALH bases Access via Vertical Insertion into 3” and 4” mains Access horizontally through cut outs PE pipe access through top tees for 63mm to 180mm PE pipe PE pipe access through a 250mm branch saddle for 355mm to 630mm PE pipe 2 bar gas approval 24, 35, 50mm and 50mm Pan and Tilt cameras
Inuktun Inuktun specialise in remote access robotics and CCTV inspection systems. They offer a range of crawlers as well as several camera heads and push rod systems. Their equipment is based around drainage applications but they do not offer live inspection capabilities. Inuktun cameras range in sizes from 23mm to 121mm and offer both axial and Pan and Tilt cameras. Ibak Ibak are an engineering firm that offer pipe inspection cameras and crawlers. Ibak also provide other equipment as well as bore cameras, powered cable reels vans, push rob systems and drainage software. They are predominantly based around the drainage industry and do not offer live access equipment.
82
Final Project Report Gap Analysis The following matrix (Figure 41) illustrates that current statue of some of the cameras investigated Company
Camera Name
Maximum working Pressure
Resolution
Minimum Pipe Size (Diameter)
Functionality
Explosion Proof
Ibak
Hydrus
1 Bar
-
50mm
Axial
No
Ibak
Juno
-
-
100mm
Axial
No
Ibak
Orion 2.5
1 Bar
-
100mm
Pan & Tilt
Yes - optional
Ibak
Orion L
-
-
100mm
Pan & Tilt
Yes - optional
Ibak
Orpheus
-
-
150mm
Pan & Tilt
Yes - optional
Ibak
Argus 5
-
-
200mm
Pan & Tilt
Yes - optional
ECA Hytec
VS 1665
1000m
380 TV Lines
32.5 OD
Axial
No
ECA Hytec
VS 870/1870/3870
300m/1000m/
460 TV Lines
80mm/80mm/
Axial
No
3000m
102mm OD
ECA Hytec
DTR 100Z
30 Bar
460 TV Lines
99 OD
Swivel
No
ECA Hytec
VSPN 154/304/3004
150m/300m/
10.1M pixels
86mm/86mm/
Axial
No
Axial
No
3000m ECA Hytec
VS 300/1300/3300
300m/1000m/
97mm OD 570 TV Lines
3000m
65mm/65mm/ 86mm OD
ECA Hytec
DTR 65 HRC
300m
450 TV Lines
65mm OD
Pan and Tilt
No
ECA Hytec
DTR 120 ZN
30m
460 TV Lines
155mm OD
Pan and Tilt
No
ECA Hytec
FTR 80 C
3m
450 TV Lines
85mm OD
Pan and Tilt
No
Synthotech
24mm
1 Bar
320 TV Lines
32mm
Axial
No
Synthotech
35mm
1 Bar
320 TV Lines
63mm
Axial
No
Synthotech
50mm
1 Bar
320 TV Lines
75mm
Axial
No
Synthotech
Synthotech PAT
2Bar/5Bar/
380 TV Lines
75mm
Pan & Tilt
No
Pan & Tilt
No
20Bar Pearpoint
P494
11 Bar
48mm OD 425 TV Lines
150mm 76 OD
Pearpoint
P494Z
11 Bar
425 TV Lines
200mm
Pan And Tilt
No
Inuktun
Spectrum 120HD
30m/3Bar
1080i
121mm OD
Pan & Tilt
No
Inuktun
Spectrum 120
30m/3Bar
525 TV Lines
121mm OD
Pan & Tilt
No
Inuktun
Spectrum 90
30m/3Bar
460 TV Lines
90mm OD
Pan & Tilt
No
Inuktun
Spectrum 45
30m/3Bar
420 TV Lines
45mm OD
Pan & Tilt
No
Inuktun
Crystal Cam
304m
400 TV Lines
50mm OD
Axial
No
JD7
LDS1000
16 Bar
HD
12" (304.8mm)
-
No
JD7
Investigator
16 Bar
HD
32"
-
No
(76.2mm)
Of all of the cameras the most applicable from each manufacturer have been highlighted, of these six cameras the most applicable are the Synthotech Pan and Tilt, the Pearpoint P494, the JD7 LDS1000 and the ECA Hytec DTR 65 HRC due to their pressure ratings. Of these four the Synthotech Pan and Tilt has the smallest outer diameter (48mm), while the Pearpoint P494 is 76mm and the ECA Hytec DTR 65 HRC is 65mm, this means that insertion of the Synthotech camera may prove easier. Of these four cameras the ECA Hytec camera has the 83
Final Project Report best resolution followed by the Pearpoint camera. All four cameras are capable of meeting the pressure requirements of the in-pipe environment.
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Final Project Report
Appendix G - SynthoTrax
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Appendix H - Relevant Standards GIS/PL2-1:2008 Gas Industry Standard Specification for Polyethylene pipes and fittings for natural gas and suitable manufactured gas part 1: General and polyethylene compounds for use in polyethylene pipes and fittings GIS/PL2-2:2008 Gas Industry Standard Specification for Polyethylene pipes and fittings for natural gas and suitable manufactured gas Part 2: Pipes for use at pressures up to 5.5bar GIS/PL2-8:2008 Gas Industry Standard Specification for Polyethylene pipes and fittings for natural gas and suitable manufactured gas Part 8: Pipes for use at pressures up to 7 bar GIS/TE/E1.8:2006 Gas Industry Standard Specification for Access tool for live entry into a low pressure polyethylene services GIS/PL2-6:2008 Gas Industry Standard Specification for Polyethylene pipes and fittings for natural gas and suitable manufactured gas Part 6: Spigot end fittings for electro fusion and / or butt fusion purposes GIS/E19:2006 Gas Industry Standard Specification for Primary iris stop bags GIS/E20:2006 Gas Industry Standard Specification for Secondary iris stop bags GIS/E48:2006 Gas Industry Standard Specification for Polyethylene service line tracing equipment GIS/PL2-4:2008 Gas Industry Standard Specification for Polyethylene pipes and fittings for natural gas and suitable manufactured gas Part 4: Fusion fittings with integral heating elements
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Final Project Report GIS/PL3:2006 Gas Industry Standard Specification for Self-anchoring mechanical fittings for natural gas and suitable manufactured gas GIS/TE/P6.1:2006 Gas Industry Standard Specification for Bypass equipment with integral pressure monitoring points for MP PE mains T/PR/D7 Work Procedure for The internal inspection of gas mains using optical inspection systems including closed circuit television (CCTV) systems AS/NZS 2537.5:2011 Mechanical jointing fittings for use with crosslinked polyethylene (PE-X) for pressure applications - Plastics pipes and fittings - Crosslinked polyethylene (PE-X) pipe systems for the conveyance of gaseous fuels - Metric series - Specifications - Fittings for mechanical jointing (including PE-X/metal transitions) (ISO 14531-3:2006, MOD WIS 4-32-14 Specification for PE80 and PE100 Electrofusion Fittings for nominal sizes up to and including 630. EN1555-3:2002 Plastics piping systems for the supply of gaseous fuels. Polyethylene (PE). Fittings ISO/DIS 8085-1. Polyethylene fittings for use with polyethylene pipes for the supply of gaseous fuels. Metric series. Specifications. Part 1. Fittings for socket fusion using heated tools AS/NZS 4130:2009 Polyethylene (PE) pipes for pressure applications AS/NZS 2033:2008 Installation of Polyethylene pipe systems AS/NZS 4645.3:2008 Gas Distribution networks – Plastics pipe systems DIN SPEC 91159 (2011-03) Plastics Piping Systems For The Transport Of Water Intended For Human Consumption - Migration Assessment - Guidance On The Interpretation Of Laboratory Derived Migration Values AS 3723-1989 Installation and maintenance of plastics pipe systems for gas Superseded by AS/NZS 4645.3:2008 ISO 4427-1:2007/Cor 1:2008 Plastics piping systems - Polyethylene (PE) pipes and fittings for water supply - Part 1: General - Technical Corrigendum 1 87
Final Project Report ISO 21307:2011 Plastics pipes and fittings - Butt fusion jointing procedures for polyethylene (PE) pipes and fittings used in the construction of gas and water distribution systems ISO 14236:2000 Plastics pipes and fittings - Mechanical-joint compression fittings for use with polyethylene pressure pipes in water supply systems ISO 4427-2:2007 Plastics piping systems - Polyethylene (PE) pipes and fittings for water supply - Part 2: Pipes ISO 4427-3:2007 Plastics piping systems - Polyethylene (PE) pipes and fittings for water supply - Part 3: Fittings JIS K 6775-3:2005 Polyethylene pipe-fittings for the supply of gaseous fuels - Part 3: Electrofusion fittings ISO 8085-3:2001/Cor 2:2008 Polyethylene fittings for use with polyethylene pipes for the supply of gaseous fuels - Metric series Specifications - Part 3: Electrofusion fittings - Technical Corrigendum 2 ISO 11413:2008 Plastics pipes and fittings - Preparation of test piece assemblies between a polyethylene (PE) pipe and an electrofusion fitting
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Appendix J - References 1
Introduction to Fluid Mechanics, Nakayama, Y.Boucher, R.F. 2000 Elsevier
2
Parker O-ring Handbook
3
Mechanics of materials, PP Benham,RJ Crawford, CG Armstrong
4
Inspector Systems Customer Information 2009
5
Gas Vac Mains and Syphn dewatering equipment
6
Machinery's Handbook (28th Edition),Oberg, Erik; Jones, Franklin D.; Horton, Holbrook L.; Ryffel, Henry H. © 2008 Industrial Press
7
Ullmann's Chemical Engineering & Plant Design, Ullmann, Fritz © 2005 John Wiley & Sons
8
Contact Mechanics, Johnson, K.L. © 1985 Cambridge University Press
9
Surface Engineering For Corrosion and Wear Resistance, Davis, J.R. © 2001 Maney Publishing
10
Introduction to Closed-Loop Control, Electric Motors and Drives: Fundamentals, Types and Applications, Third Edition, Austin Hughes, 2000
11
Flight Control Systems: Practical Issues in Design and Implementation, by Roger W. Pratt, 2000
12
Mechanical Engineer's Pocket Book, Third Edition, 2006
13
Sigma Aldrich, 2-Ethylhexxyl Methacrylate data sheet
14
Sigma Aldrich, Hydroxy Propyl Methacrylate data sheet
15
Sigma Aldrich, Cumene Hydroperoxide data sheet
Airblast. Airblast B.V., P.O Box 1075, 1700 BB Heerhugowaard, The Netherlands Tel.: +31-72-5718002 Fax: +31-72-5714340 E-mail:
[email protected] Web : http://www.airblast.com/ AIT Advanced Inspection Technologies. Advanced Inspection Technologies Inc.,7351 Office Park Place, Suite 146, Melbourne, FL, 32940, United States Tel: +1 (321) 610-8977 Fax: +1 (321) 574-3814 Web : http://aitproducts.com/ Allied Pipefreezing Services Limited Allied Pipe Freezing Services Ltd, Unit 2 Caroline Court, Billington Road, Burnley, Lancashire, BB11 5UB, United Kingdom Tel: 0845 658 0425 Fax: +44 (0)1282 410241 Email:
[email protected] Web : www.alliedpipefreezing.co.uk KMT Aqua-Dyne KMT GmbH - KMT Aqua-Dyne, Auf der Laukert 11, D-61231 Bad Nauheim, Germany Tel: +49-6032-997-283 Fax: +49-6032-997-274 E-mail
[email protected] Web: www.aqua-dyne.com/ Clemco Anschrift, Carl-Zeiss-Strabe 21, D - 83052 Bruckmuhl Tel : +49(0)80 62 - 9008-0 Fax : +49(0)80 62 - 9008-50 Email :
[email protected] Web : http://www.clemco.de/ Hennigan Engineering 90
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[email protected] Web: www.henniganengineering.com/ Perco Perco Engineering Services Ltd, Cornhill Close, Lodge Farm Industrial Estate, Northampton, NN5 7UB, UK Tel : +44 (0) 1604 590200 Fax : +44 (0) 1604 590201 http://www.perco.co.uk Fraunhofer IFF Fraunhofer Institute for Factory Operation and Automation IFF, Postfach 14 53, 39004 Magdeburg, Germany Tel. +49 391 4090-0 Fax +49 391 4090-596 Email :
[email protected] Web : www.iff.fraunhofer.de Weda Weda Sweden, Wedavägen 4A, Södertälje Phone: +46 (0)8-550 325 50
Fax: +46 (0)8-550 310 50 E-mail :
[email protected] www.weda.se Non Entry Systems Non Entry Systems Ltd. Dragon House, Bruce Road, Swansea SA5 4HS United Kingdom Tel : +44(0)7966152187 FAX : +44(0)700609862 Email :
[email protected] Web : www.nonentry.co.uk Secor Telephone: 281-556-1661 Fax: 281-556-1683 Email:
[email protected] Web: www.secoronline.com/secorHome12.asp Urakami Research and Development Co. 4-17-24 Konandai, Konan-ku, Yokohama 234-0054 Tel:+81-45-833-5033 Fax :+81-45-832-5081 E-mail:
[email protected] Web www.urakami.co.jp/index.html Suction Excavator Via Croce, 26, 35011 Campodarsego, Padova - Italy Tel : +39 049 5564422, Fax : +39 049 5564784
[email protected] Web : www.suction-excavator.com ALH Systems Limited 1 Kingdom Avenue, Northacre Industrial Estate, Westbury, Wiltshire, BA13 4WE Tel: 01373 858234 Fax: 01373 858235 Email:
[email protected] Web : www.alh-systems.co.uk Hy-Ram Engineering Ltd Pelham Street, Mansfield, NG18 2EY Tel: 01623 422982 Fax: 01623 661022 E-mail:
[email protected] Web : www.hyram.com/index.php Metal Samples Corrosion Monitoring Systems P.O. Box 8, 152 Metal Samples Rd, Munford, AL 36268
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[email protected] www.alspi.com/access.htm NupiGeco Via Stefano Ferrario Z.I. Sud-Ovest, 21052 Busto Arsizio (VA) Tel : 39 0331 344211 Fax: 39 0331 351860 Email :
[email protected] Web : www.nupigeco.com/ Westwood Pipelines Westwood Pipelines Ltd, Unit A, Station Road Industrial Estate, Epworth, Nr. Doncaster, DN9 1JZ Tel: +44 (0)1427 875770 Fax: +44 (0)1427 875790 http://www.westpipes.com/ George Fischer Limited Paradise Way,Coventry CV2 2ST Tel: 024 7653 5535 Fax: 024 7653 0450 Email:
[email protected] Web : www.georgfischer.co.uk The Fusion Group Smeckley Wood Close, Chesterfield Trading Estate, Chesterfield, S41 9PZ, UK Tel : +44 (0)1246 260111 Fax : +44 (0)1246 450472 Web : www.fusiongroup.com Plasson UK Ltd Plasson House, Albert Drive, Burgess Hill, West Sussex RH15 9TN Tel: +44 (0) 1444 244446 Fax:+44 (0) 1444 258683 Email:
[email protected] Web : http://www.plasson.co.uk/main.asp Argu Phone: (08) 9419 3686 Fax: (08) 9419 3187 Email:
[email protected] Web : http://www.agru.com.au/index.htm Friatec Steinzeugstrasse 50 68229 Mannheim Tel : +49 621 486-0 Web : +49 621 486-1279 Email :
[email protected] Web : http://www.friatec.com/content/friatec/en/index.html Radius Systems Berristow Lane, South Normanton, Alfreton, Derbyshire, DE55 2JJ Tel : +44 (0)1773 811112 Email :
[email protected] Web : http://www.radius-systems.com/index.asp WRc Plc Frankland Road, Blagrove, Swindon, Wiltshire, SN5 8YF Tel: +44 (0) 1793 865000 Fax: +44 (0) 1793 865001 Email:
[email protected] Web : www.wrcplc.co.uk ATS Enterprises Unit 2/13-15 Steel Street, Capalaba Queensland 4157, Australia Tel : 61 (07) 3245 7766 Fax : 61 (07) 3245 3611 Web : http://www.atsent.com.au/
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[email protected] Radiodetection (UK), Western Drive, Bristol, BS14 0AF, UK Tel: +44 (0) 117 976 7776 Fax: +44 (0) 117 976 7775 Email :
[email protected] Web : www.radiodetection.com Ridgid Tel : 1-800-474-3443) http://www.ridgid.com/ ULC Robotics 55 Corbin Ave, Bay Shore, NY 11706 Tel: 631-667-9200 Fax: 631-491-0128 Email :
[email protected] Web : www.ulcrobotics.com Inspector Systems Johann Friedrich Böttgerstr, 19 63322, Germany Tel : +49 6074 917 123 0 Fax: +49 6074 917 123 9 Web : www.inspector-systems.com RedZone Robotics 91 43rd Street Pittsburgh, PA 15201 | (412) 476-8980 Email :
[email protected] Tel : +1 (412) 476-8980 Web : www.redzone.com EV Adelaide, SGS Upstream Services, 65 Kapara Road, Gillman, SA 5013, Australia Tel: +61 8 8447 6833 Fax: +61 8 8447 6442 Units 4 & 5, Energy Development Centre, Energy & Science Park, Bridge of Don, Aberdeen, Scotland, AB23 8GD Tel: +44 1224 822555 Web : www.evcam.com Halliburton 10200 Bellaire Blvd. Houston, TX 77072 Tel : 281 575 3000 Web : www.halliburton.com Gradient Lens Corporation 93
Final Project Report 207 Tremont Street Rochester, New York 14608 Call 800.536.0790 or 585.235.2620 Web : www.gradientlens.com Katimex Bahnhofstr. 50, D- 54584 Jünkerath, Germany Tel. +49 / 65 97 / 92 77 - 20 Web : www.katimex.com Meta Vision Systems Ltd Oakfield House, Oakfield Industrial Estate, Eynsham Oxfordshire, OX29 4TH UK Telephone: +44 1865 887900 Fax: +44 1865 887901 Web : www.meta-mvs.com R&R Visual, Inc. 1828 W Olson Rd, Rochester, IN 46975, United States Email :
[email protected] Tel: 800-776-5653 Fax: 574-223-7953
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Appendix K - Bond and Bolt case study Case study number
CS-Bond and Bolt 1
Mains diameter
48”
Case study location
London
Mains pressure
31mbar
Case study date
2011
Survey distance
160m
Equipment used
SynthoTrax and Bond & Bolt
Introduction With large diameter mains needing to be inspected and replaced, Synthotech pioneered the SynthoTrax system for small access into live mains. The Bond & Bolt system developed by ALH Systems in conjunction with Synthotech and National Grid Gas for The SynthoTrax System now allows the excavation to become even smaller. Overview Traditionally to gain live motorised access into a large diameter gas main a section had to be cut out. This involves an Iris Stop operation, bypass and large excavation providing high risk live gas work, major environmental impact and high excavation costs. Typically an excavation was approximately 10metres long by 2.5 metres wide by 2.5metres (62.5m3).
2.5m
10m
2.5m
With the SynthoTrax system, the motorised vision vehicle is vertically launched under live gas conditions into the main. The excavation requirements are significantly reduced, eliminating the requirement for an Iris Stop operation, bypass, lowering the risk of the live gas work, environmental impact and reducing the large excavation costs. Typically a SynthoTrax system excavation is less than 2.5m x 2.5m x 2.5m (15.63m3) SynthoTrax and Bond&Bolt fixes a slave launch saddle onto the top of the large diameter main using a bonding agent and bolt fasteners into the parent pipe. This allows an access drilling to be made into the main without any need to excavate round or below the main for anchorage and security. This again significantly reduces the large diameter excavation requirement thus minimising even further the risk of live gas working environmental impact and excavation costs, while maximising the operational efficiency. Typically a SynthoTrax and Bond&Bolt system excavation is less than 1.2m x 1.2m x 1m on a 48”main (1.44m3). A SynthoTrax excavation is a 75% saving and SynthoTrax and Bond&Bolt excavation is a 97% saving against volume displaced.
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Final Project Report Traditional Excavation Methodology
SynthoTrax Excavation
SynthoTrax and Bond&Bolt
62.5 m3
15.63m3
1.44m3
Conclusion SynthoTrax and, SynthoTrax and Bond&Bolt represent significant cost reduction while reducing the environmental impact, mitigating excavation risk, live gas working and reducing disruption to third parties. SynthoTrax and Bond&Bolt is the operational solution of the future.
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Crossrail Ltd is building the exciting new East to West link across Central London. This route involves 21 km`s of twin – bore rail “running” tunnels and above ground lines. National Grid Gas own and operate Pipework in the Medium Pressure Tier located above this planned tunnelling works. Integrity of this Major asset is of paramount importance to the project and the safety of London. This facilitating work was to concentrate on ‘live’ large diameter Medium Pressure Gas Mains located in ground settlement areas above tunnel boring activities and was to give confidence to National Grid as to their assets performance during and following the planned works. Gas Mains requiring assessment were identified by the Network Operator – National Grid Gas (Distribution). This confidence would be achieved by Internal Robotic surveying. This was chosen as the preferred method of assessment and would confirm the presence, location and condition of existing internal seals assembled through the 1960`s and 1970`s from a small excavation footprint. It would also allow cataloguing of any unidentified, unknown or significant features within the asset. Robotic inspection was chosen rather than that of the alternative – excavating and encapsulating each joint. Factors in this decision would include the cost of encapsulating and the amount of excavation required for encapsulation on a main of this size – due to the distance of approximately 12 feet between joints on 36” or 48” diameter main and the depth of cover, the resulting work would in effect require an ‘open cut’ trench for the entire identified Gas main. Synthotech Limited was appointed to undertake in-pipe visual surveying using the SynthoTrax™ Robotic Inspection System. Aim: The aim of the SynthoTrax™ Survey was to provide video footage, screen shots, site photographs and location measurement of joints and other in-pipe items of interest across the identified settlement areas. Objectives: 1) Survey as far as deemed possible by the Synthotech Operator / required by National Grid Gas representative. The survey will be conducted from one access point and extended as far as deemed safe or practicable. 2) Prepare and Present video footage recordings of all observations undertaken. 3) Highlight each joint or item of interest by taking a screen shot picture from the visual survey 4) Give a location distance of each joint/item of interest from the entry point. 5) Provide site photographs of excavation and marked position of items of interest. Benefits of SynthoTrax: Selection and use of the SynthoTrax™ system over the encapsulation of individual joints includes; Small access excavation footprint – typically 4mx4m x (mains diameter & depth of cover for a circumferentially chained success base, 2m x 2m x depth of cover , for a Bond and Bolt access drilling. One excavation to allow visual surveying of multiple joints – up to 200metres in each direction rather than one excavation per joint as per Encapsulation No further works required should a Mechanical internal seal be observed, and believed to be in good condition. Reduced time to complete, a SynthoTrax™ survey is completed in less than one day. Reduced risk of injury to Operative and Public due to minimal excavation works Reduction in traffic management issues Reduced cost to complete work on identified pipeline Reduced environmental impact as a result
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Change in material to steel
Rise in main to square section over Bridge
Acro props and rail in CIPP over bridge
Location: Commercial Road, London, E1
Potential Cost Benefit Against a traditional large excavation, flows stop and horizontal insertion, a saving in excess of £60,000 for two access points. Against multiple excavations using push rod systems, the cost saving would be approximately £60,000 against eight or nine smaller excavations. Approximately 115 joints, preventing 114 excavations in central London, preventing 115 encapsulations at an approximate cost of £5,000 per excavation is £570,000 saving.
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