Board Mill of SCA Obbola Invested in Web Monitoring System
Procemex Ltd was recently awarded a contract to SCA Obbola paper mill for a delivery of a Web Monitoring System. Commissioning in 2015, the new modern Web Monitoring System replaced the previous one that reached the end of life. This new system will substantially increase quality monitoring and decrease web break times and therefore improve SCA Obbola’s positioning at the market.
Procemex Web Monitoring System is a proven solution for downtime reduction at paper, board and pulp mills. Should a web break occur, a film recording of the event is captured and stored for further analysis. A new generation of high resolution smart camera and strobe LED lighting technology is able to cope with speeds in excess of 3000 metres per minute (9000 ft/min).
Highly Quality Conscious
SCA Obbola team, Mr. Göran Holmlund, Supervisor Maintenance Automation and Mr. Jonas Långström, Production Technician at SCA Obbola, began to look for a modern web monitoring system for the kraftliner machine. They had faced some problems with the former system, therefore they decided to have several trial runs made with different web monitoring system suppliers. Procemex Pinhole and Procemex Standard Camera solutions were also evaluated at that time. After careful testing and comparison, SCA Obbola team decided to go with Procemex Web Monitoring System.
“We needed a tool for trouble shooting, since we had a lot of web breaks,” says Jonas Långström. “We did a lot of guessing and that’s why we needed a system that can help us with our board machine.”
Göran Holmlund continues that they had only five cameras still working in the old system, which had no support any more. They turned to different suppliers and made several comparisons between different systems. Some of the cameras were too big to fit into tight spaces available. The final comparison was made between two suppliers, Procemex being one of those. “We visited also many companies for bench-marking,” Mr. Holmlund pointed out.
“Demonstrations and trials were made before the actual decision ,” said Göran Holmlund. “We were not happy with the first trial, because the camera positions were not optimal, but the second one was very good. We had better image quality and we were happy with the results.”
Cameras along the Web
The whole system comprises of 18 cameras, out of which 17 are Procemex Pinhole cameras and one mobile, movable trouble shooting camera. Since then, high-speed cameras in stainless steel housings have captured images of every centimetre of web as it runs through the board machine. Even at the extreme wet and hostile conditions of a board machine Pinhole cameras stay clean by means of high speed air flow. The air is blown through a 5 mm hole in front of the camera housing. As the air flow speeds up when passing the pinhole lens it forms a strong protection against dirt and prevents water and dirt from entering the lens and camera housing. The housing has no protection window that could get dirty or wear out.
Additionally, benefits of pinhole cleaning are trouble-free operation, low air consumption, 100% continuous visibility and the simplicity of the concept. There are no moving and wearing parts.
The rapid development of paper and board machine speeds has meant that the human eye has a little or no chance of spotting faults in the manufacturing process. Obtaining evidence about the root causes of sheet breaks have become very difficult without technical support.
Break Root Cause Capturing
Procemex technology makes it easy to capture images and identify the root cause of web breaks. To be able to see and detect different web break reasons, the smart cameras need good lighting. Procemex Eco-Powered Strobe LED Flashlights have very low energy consumption and remain cool preventing fires which may occur with conventional hot halogen lights, as well as avoiding dirt sticking on the glass due to the hot surface of older type lights.
The web monitoring strobe LED lights are in stainless steel housings along the paper machine. They have been designed to take ambient temperatures up to 250C/480F and have an indirect cooling system for hot positions. Free choice of air or water for cooling brings innovation.
The image quality became better with Procemex system, explained Göran Holmlund, “The lights are better, so the image quality differs a lot from the previous one, defects are shown much clearer. The lights work perfectly.”
“We chose Procemex for a couple of reasons: Picture quality being number one, then ease of use. The handling of the system is easy and minimum maintenance needed. Also the upgrading is made easy, you don’t need to change the camera, but you can change the camera properties by the software,” say Långström and Holmlund together.
“Pinhole cameras keep clean, you don’t have to polish the lens all the time, Procemex cameras lights? stay clean. And this affects of course to the image quality, as well. This is the major advantage compared to the old system,” says Jonas Långström.
When Web Break Occurs
But how does the SCA Obbola team actually react when a web break occurs? After a web break, the cameras, which operate constantly, send the most recently stored video data from the camera’s RAM memory to the system’s hard disc for further analysis. A graphic display on the screen of the Procemex system shows web break history and the precise point of the break of the web. Therefore, the break can be analyzed very quickly.
“Now we can locate the web break causes more easily, troubleshooting is faster and easier. Also analysing is quick, because the cameras are synchronized with each other,” Johan Lundström states. ”The cameras cover a wider area of the web and that helps us in detecting the defects more easily.”
The Procemex cameras are synchronized in such a way that the same point on the web is in view from one camera position to the next. The data recording tracks back to see where the web fault or paper defect - for example an edge crack or a hole—appears for the first time.
No More Unnecessary Fixing
The time saved in determining the cause of a break and the increased production line efficiency directly contribute to the rapid return on investment for a Web Monitoring System.
At SCA Obbola the adapting of the system has also been effortless: “The machine teaches the operators itself,” commented Jonas Långström, “ Very simple to use.”
“The project as whole went well, the team worked together, Procemex had a lot of meetings with us, and they listened to our wishes.”
The mobile camera is included in the Procemex Web Break Monitoring System and it is used continuously at the mill: “We use the movable camera all the time, looking for defects in different places. The only problem there is to have a right kind of light at the spot, but this will be fixed also shortly.” In the set-up phase Procemex did fine-tuning and re-positioning of the cameras to get the optimum images of every camera position.
When thinking about the payback time of the system, Jonas Långström points out that “Although the system is expensive, it’s an incredible tool, I don’t think we could trouble-shoot without a camera system.”
“If you don’t have any camera systems working, you cannot prevent web breaks as well as we can do now,” emphasizes Johan Lundström. “We can locate the web defects and fix them before any web breaks happen. And we can prevent repeated web breaks to happen.”
For more information:
Mr. Jari Keranen
Director, Sales, Procemex Ltd
tel. 358 40 548 3324
Mr. Mika Valkonen
CEO, Procemex Ltd
tel. 358 14 337 2111
Mrs. Kristiina Pispala
358 40 191 8882