Transcript
SMART Process Monitoring System For Improved Operational Efficiency Of Raw Material Handling Plant SubhraDhara1,R.K.Jha2 , H.N.Das2,A.Arora1 , J.Dasgupta3 & M.Das3 1
R & D Centre for Iron & Steel Bokaro Centre, SAIL, Bokaro, India 2
R & D Centre for Iron & Steel, SAIL, Ranchi, India 3
RMHP, Bokaro Steel Plant, Bokaro, India Email:
[email protected]
ABSTRACT Raw Material Handling Plant network comprises of 4 wagon tipplers, 7 stackers & reclaimers, conveyor systems having 20 junction houses and 6 additional junctions located over a widespread area (5 sq. Km aerial distance). Conventionally the critical co-ordination job had been undertaken by walkie-talkie & max intercom, relied solely on manual supervision. Inefficient operation lead to various operational problems e.g. Scrap/foreign material in transfer chute Off-centre of conveyor Jamming due to spillage of material Empty conveyor etc. resulting operational delay of 160 hrs./annum. In addition, there were reported problem of accidental double wagon tippling, which called for longer shutdown periods. Smart process monitoring system has successfully been designed, developed & commissioned in bulk raw material handling scheme, to de-bottleneck the limitations manual supervision. 36 Charged Coupled Device cameras were installed, for optimal coverage of whole RMHP operation. Out of 36 cameras, 16 Analogue cameras were used in tipplers & 20 nos. Internet Protocol based cameras were used in junction houses & transfer points. Both analogue & IP cameras were connected to network switches connected in ring topology using single Fibre Protocol (SFP), which were then connected to server. Client PC connected to the server had been installed at MCC#5, able to view images, even if any localised breakdown happens. CCD camera electronics and accessories were engineered and manufactured to provide reliable continuous remote viewing of critical processes and operations in hazardous environments. CCD cameras had been task-engineered to the specific viewing requirements by restraining high light condition used in industry. Linux
Based DVR adopted one chip technology for storing of image data on real time basis termed as simultaneous viewing and recording at 25 frames/sec. The system utilized one processing chip per camera to produce the best possible picture quality in both split and full screen display maintaining a balance between image contrast and brightness to an optimumvalue.Intelligent motion detection had also been configured for each channel, maximizing disk efficiency by ignoring periods of non-activity. The data search function provides quick image search and easy playback. The DVR system adopted most recent H.264 codec technology for image compression/de-compression and also can transmit image over LAN using TCP/IP protocol. In this application, four channel DVR with 1 TB hard disc capable of storing at least 07 days’ data has been chosen. Fibre optic cables were used for transmitting the camera signal, for low disturbance of signal and overcoming distance limitations. Suitable network switches at camera end and control room is used for the purpose. The system provides both local view of the wagon tipplers operation in wagon tippler control room and remote viewing of the same in master control room.The system eliminates inherent process limitations such as inaccurate placement of wagons in tipplers, offtracking of conveyor belt, over spelling of raw materials with special features like event recording, alarm generation and analysis of network video images etc. After the SMART process monitoring system, operational delay has been reduced from 16.02 hrs./month to 0 hrs./month. Additionally, no incidence of accidental double wagon tippling due to rolling back of wagon has been occurred, which has ensured safe working during de-coupling of wagons Keywords: CCD camera, process monitoring
INTRODUCTION Integrated steel plant produces numerous steel products generally classified as flat and long products with varying physical & chemical properties from basic raw materials such as iron ore, coal, limestone etc. on continual basis. There are several stages for operation between conversion of raw material to finished steel products. In modern steel plants, CCD cameras and DVR were successfully deployed mainly for process viewing of plant production process. The present application was considered for the Raw Material HandlingPlant
(RMHP) of Bokaro Steel Plant. The prime role of RMHP is receive & prepare the raw material as per design specification and then transport it onwards to further units such as Blast Furnace, Steel Melting Shop & Refractory material plant etc. for further processing. The Layout of RMHP is shown in Fig. 1. The raw material is received at wagon tippler and the same is tippled on to belt conveyors. The raw material is then conveyed to various distances for bedding and blending operations with the help of a network of conveyors and junction houses. The entire movement of conveyors for desired raw material movement is controlled from a central location, namely master control room (MCC-5). The control room operators do not have a direct view of raw material movement leading to sometimes undesired operation. In order to improve this complex process, an on-line viewing of raw material movement using camera vision system has been installed. In the installed system several CCD cameras has been positioned at the strategic locations at wagon tipplers and junction houses end for viewing the raw material movement.
CCD CAMERA SYSTEM CCD camera system can be broadly divided into two types namely analogue system and IP (Internal Protocol) system. A basic analogue system consists of a number of Analogue cameras connected to a Digital Video Recorder (DVR). The DVR is in return connected to the network switch over a LAN. A basic IP system consists of a number of IP cameras connected to network switch and a video management server over a LAN.
SYSTEM DESCRIPTION The system description of CCD camera over a fiber optic network at Raw Material Handling Plant for viewing of raw material is elaborated in this section. CCD cameras were installed in critical location of raw material handling plant. Analogue cameras connected with Digital Video Recorder (DVR) were used in some locations (wagon tipplers) and IP cameras were used in other location (Junction houses). The analogue camera were connected through DVR and IP camera directly to industrial grade network switches connected over a fibre optic network having a ring topology. Analogue cameras were selected for low latency requirements where as IP cameras were selected for obtaining high definition (HD) images. The image was recorded on motion detection mode where in the image was recorded only
Fig.1.0: Analogue and IP camera location when there was movement so that unnecessary recording during conveyor stoppage time is avoided. This has two basic advantages, firstly only the relevant image is recorded making it easy to search and analyze and secondly it saves the critical hard disc space in computer. Additionally, the recorded image can be played back in slow motion (1/4 x 1/8 x 1/10 x etc.) to evaluate reasons of any wrong operation during coil movement. Wagon Tippler (WT): Wagon tipplers receive the material through tippling the railway wagons on the bunkers. Here, the wagons are de-coupled manually, endangering the life of the personnel, hence monitoring of de-coupling process is monitored in the WT cabin. Area A in the Fig. 2. After tippling the wagon is shunted out of the tippler to place new loaded wagon, sometimes due to freeness of the wagon shunted out, it rolls back into the tippler and white tippling cause accident. Area B in the Fig 2.
A
B
C Conveyor
At - 25 m (below ground level)
A-Area where de-coupling of wagons are done manually, danger of life B- Area where wagons move back ward and cause accident C- Area where the tippled raw material is fed through conveyor and the alignment of belt on the drum
Fig.2.0: Wagon Tipping and conveyor movement tracking through camera
Through bunkers the material falls on the conveyor. The conveyor belt alignment and movement of raw material, ensure the function of the bunker. Area C on the Fig. 2. Junction Houses: The junction houses are,made to a) Change direction of the material movement. b) Route for different material to desired location. The different routes are at different levels, so sometimes junction houses are multi level. The tipplers receive different material required for steel making and are fed to junction houses. The junction houses provide route for different material to reach their desired destinations like: 1. To coke ovens for coal. 2. Lime stone, Dolomite to RMP. 3. Different grades of I/O to stacker, Reclaimer yard. 4. Coal fines and ore fins to sintering plant etc.
The image was recorded on motion detection mode where in the image was recorded only when there was movement in coil, so that unnecessary recording during mill stoppage time is avoided. This has two basic advantages, firstly only the relevant image is recorded making it easy to search and analyze and secondly it saves the critical hard disk space in computer. Additionally, the recorded image can be played back in slow motion (1/4 x, 1/8 x, 1/10 x etc.) to evaluate reasons of any wrong operation during coil movement.
REAL-LIFE DEPLOYMENT SCENARIO AND CONSTRAINTS Deployment of CCD system over a fiber optic network in a fully operational raw material handling plant was not an easy task as Wagon tippling operations and raw material movement are processed all around the shop floor on continual basis. The raw material movement typically uses unloading of wagons carrying raw material with the help of wagon tipplers, gravity falling of raw materials on conveyor belt through hoppers, again raising the conveyor belt over a inclined plane to some distance, terminating the same at junction house. The heightened raw material is again made to fall at junction house to another set of conveyor belt with a change of direction. This cycle of raising the raw material followed by gravity following and change of direction continuous till the raw material reaches it designated place with the help of stackers located at end of conveyor network. The entire flow of raw material at RMHP was studied and key vantage points were identified so that the entire RMHP raw material movement can be had at a glance at a central monitoring station using a limited no. of cameras. It was also observed that gravity falling of material from junction houses through feeders & chutes generated a lot of dust impairing visibility either through naked eyes or camera. This problem was obviated by placing the camera away from the junction houses but pointing to conveyors coming out of the junction houses. This resulted in giving an idea of material movement at junction houses but at the sometime gave a clean for cline of the raw material moving on the conveyor. During installation, one of the most important aspects was cable laying, which included RF co-axial, fibre optic & power cables. Cable laying and routing was done so as to make it clutter free and point free as far as possible. The fibre optic cable was laid using a ring topology. HDPE pipe was extensively used for cable laying. Wiring diagram of the proposed confirmation was finalized at the drawing board before the commencement of actual wiring at site. The network has be designed with robust hardware like Analogue & IP cameras, monitors,
power supply, armoured cables (fibre, RF, & power) PC server etc. camera house is also another issue for designing such system in a dusty industrial environment. IP 66 rated camera housing was used and the camera was mounted suitably at a distance so that dust effect is mitigated. Camera housing with continuous air pushing is not recommended as supply of clean and dry air may not always be possible at the shop-floor. Weekly cleaning of camera housing is recommended with the help of portable air blowers. A brief description of activities undertaken is given below.
Design and development of scheme for viewing of raw material movement system using camera vision technology in harsh environmentalconditions.
The location of camera is shown in Table 1.0 The major components of system is shown in Table 2.0 Interfacing of camera signal with mill wide fibre optic network for transmission of video image to control room. Development of method for capturing of raw material movement and generating respective snapshots through application software. The network enclosure location is shown in Fig. 3 Sl. no.
Table 1.0: Camera locations at site Camera location Qty. Analog
1
Wagon tippler – 1
4
2
Wagon tippler – 2
4
3
Wagon tippler – 3
4
4
Wagon tippler – 4
4
IP 5
Junction House 3
6
Junction House 20
7
Junction House 11
3
8
Junction House 12
6
9
Other Locations
3
Total
4 4
32(16 Analog and 20 IP)
Table 2.0: Major components of the system Sl. no.
Components
1.0
Analog camera & DVR systems with accessories
2.0 3.0 4.0
IP camera system with accessories Network switches & accessories Fiber Optic (FO) cable, RG & power cables with accessories
5.0 6.0
Networking system & software Console & power supply
WT
DVR1
DVR1
Switch
DVR 3
DVR1
JH 20 Switch Switch Client PC
Server
Switch
JH 11
Switch
Client PC
Client PC
JH1 2
MCC-5
Fig. 3.0: Network configuration
Switch
JH3
The Master Control Room location where viewing of cameras is done is shown in Fig.4
2 x 4 camera
2 x 4 camera 2xMonitor
Loc.: WT-1/2
2xMonitor
PS WT-1/2
WT-3/4
SWITCH
DVR
DVR
LIU
DVR
DVR
PS
PS
DVR Enclosure
3 Camera
4 Camera
4 Camera
DVR Enclosure
JH-11 JH-12 6+ 3 Camera
Network Enclosure (IP65)
PS SWITCH
JH-20
JH-03
PS
PS
PS
SWITCH
SWITCH
SWITCH
LIU
LIU
LIU
LIU Network Enclosure (IP65)
DVR enclosure -2 Network enclosure(IP 65)-5 36U/42U -1
Network Enclosure (IP65)
Network Enclosure (IP65)
Master Control Room (MCC-05) PS SWITCH LIU Network Enclosure (IP65)
36 U/42 U
Fig. 4.0: Network Enclosures Location
The Overall network design for analogue & IP Camera is shown in Fig.5
Network Enclosure (IP65)
SWITCH
SERVER (VMS software)
CLIENT PC (IP Camera viewing)
JH-11
JH-12
JH-20
JH- 03
CLIENT PC (Central management software for DVR )
WT-1
WT-2
WT-3
WT-4
Fig.5.0: Control room diagrams
Analogue camera
DVR
Wagon Tippler Control Room
Master Control Room
IP camera
Network Switch
Junction Houses
Fig. 6.0: Flow chart of network design
RESULTS 1. Daily sinter production rate from Sinter Machines#2&3 improve by 6% (Operational delay by reducing stoppage of Sinter Plant due to stoppage of conveyor belt reduced from 16.02 hrs./month to 0 hrs./month 2. Operational delay by reducing stoppage of Blast Furnace due to stoppage conveyor belt reduced from 9.68hrs./month to 0 hrs./month
of
3. No incidence of accidental double wagon tippling due to rolling back of wagon has been occurred, which has ensured safe working during de- coupling of wagons
CONCLUSION
Camera vision systems over a Fibre Optic Network are useful for close monitoring of any continuous process, which otherwise dependant on operator skills, who may remain blind folded to the object of interest due to vision hindrances Viewing of raw material movement has resulted in correct movement of raw material from wagon tippler to junction houses. This has led to reduced conveyor off-centre spillage of material & scrap/foreign material due to early viewing of such events.
System cost is comparatively low with high quantified benefits, leading to its justification on the Return on Investment (ROI) scale. Design of the system is such that it can be deployed to any raw material handling plant for process monitoring application in steel
REFERENCES 1. 2. 3. 4.
http://www.vision-systems.com/ www.pelco.com http://www.panasonic.com/business/psna/products-surveillance-monitoring/index.aspx http://www.thefoa.org/
