New quality-based line speed control
Papertech’s Slow-on-Defect converting line speed control system enables line speed control based on the quality of product to be converted. Line downtown due to unexpected quality related process interruptions can be greatly reduced, improving line availability and therefore OEE.
Many converting line operators are used to loading parent reels on their lines without knowing anything about the quality of the tissue they are expected to convert. Unfortunately, the quality of the base tissue web has a lot to do with how efficiently the converting line can operate. Large holes, edge tears, folds and creases can all lead to process interruptions when the line speed is too great to allow the defects to pass through the various converting processes without issue.
Fortunately, web inspection systems on tissue machines can capture all web defects contained in a reel. A parent reel quality report defining the location of each defect in the reel can be passed to a converting line when a parent reel is loaded into the unwind cradle. New quality-based line speed control systems can interpret the quality report and can control the converting line speed based on predefined criteria. In this manner a line can slow to a crawl to pass a large hole and then speed up again when no web defects are expected. The converting process is not interrupted, and line efficiency is not compromised by the usual web break, clean-up and line restart process.