Industry 4.0 is all the rage amongst larger tissue producers and purports, amongst other things, to enable large-scale machine-to-machine communication such that individual manufacturing processes are no longer conducted in functional silos. Instead, holistic knowledge of all processes is to enable a continuous improvement cycle that drives different manufacturing performance measures, such as overall equipment effectiveness (OEE) to new levels, ultimately improving the enterprise’s earnings.
Unfortunately, production “silos” without cross process thinking still exist even in the most advanced facilities. It is, for example, not uncommon that the quality metric on most tissue machines is to get paper with correct weight, moisture and perhaps caliper onto the reel without a web break. Anything that gets reeled can be placed in the warehouse and/or passed to converting. Little to no concern is given to how the actual tissue surface quality might affect downstream converting operations.
The calculated OEE, a multiple of the tissue machine’s availability, performance and quality of the product produced, will reflect an inflated value as the quality measure will be positively skewed. Production looks great while potential problems are transferred downstream. It is no wonder then that most converting plant managers see tissue production as their primary enemy in meeting operational targets.
Tissue web defects such as holes, edge cracks and creasing can cause web breaks in the converting line, glue contamination, embosser wrap ups and other process problems. Converting line performance will suffer the most, but also line availability and quality. OEE can often seem stuck at levels below 50% – the room for improvement is almost always huge. But, are line operators or converting plant managers to blame? The answer is typically a resounding No!
Fortunately implementing better tissue machine quality control, tissue machine-to-converting line communication and converting line quality control is not difficult today. Papertech’s TotalVision web inspection and web monitoring solution makes true quality readily apparent and will assist production to:
- Detect and classify defects and mark their locations on a reel defect map.
- Provide the ability to trace defects to their root cause with visual information.
- Provide the ability to detect repeating defects and to match these with machine components that exhibit the same or similar rotational frequencies.
- Provide the ability to determine the root cause of web breaks or other visible process problems.
- Provide the ability to differentiate between dust and the actual web so that only true defects are recorded.
- Provide the ability to pass parent reel quality records to downstream processes.
Most importantly, TotalVision will prompt action to improve quality as the corrected machine OEE will beg for upward adjustment. Tissue machine-to-converting line communication is made possible via Papertech’s Slow-on-Defect solution, which allows for automated control of the converting line speed based on the classification of reel defects that are to pass through the converting process.
Slow-on-Defect will have a big impact on converting line performance, but also on quality (e.g. by allocating parent reels of better quality to outer plies on a multi-ply product) and on line availability (e.g. by avoiding line setup events).
Converting line OEE can be further optimized via Papertech’s QualityVision solution for online quality inspection that:
- Inspects the base tissue web, embossing and print and provides immediate quality feedback.
- Provides a final product quality record.
- Assists in rapid embosser and printer setup.
- Eliminates setup waste and reject waste. Papertech’s cross process solutions make some of Industry 4.0’s promises reality today. The “wall” between tissue production and converting is being broken down with very positive results.
Significant OEE increases on tissue machines and converting lines are not uncommon and investments in Papertech’s tissue solution set are often paid back in less than 6 months. Papertech welcomes collaboration with all those endeavoring to improve the future of tissue making. Please contact them for more information.
