Splicer And Infeed Troubleshooting - Web Breaks On The Splice

The following troubleshooting guide applies specifically to web breaks occurring at the moment of the splice.

Problem:  Poor or outdated splice tape.
Solution: Splice tape has an expiry date and must be stored at a cool range of temperatures in order to retain its properties.  Try a different batch of tape.

Problem:  Damaged paper.
Solution:  Enough paper must be stripped off the roll before mounting it. This shouldn't be much.  However any nick will cause the brake.  Inspect rolls carefully.

Problem:  Temperature of paper at splice.  
Solution:  Rolls that have been in cold storage do not work well on splices.  The various tapes in the industry are good, but when the web is very cold, the splice will not always stick well.  Some printers will get a device especially designed to heat the core of the roll so that the temperature will be just right.  Either heat up the temperature of the paper in storage or buy a core heater.  Probably the latter has the quickest payback.

The following solutions apply to a flying paster

Problem:  Splice not timed properly (flying paster)
Solution:  Change the position of the marker (usually a black sticker) to a different position.   Though it is a high speed process, there is usually a little room for forgiveness.  Try to find the sweet spot.

Problem:  Rollers are wearing (flying paster)
Solution:  At the moment that the splicing arm fires, it is usually a foam roller that will press the moving web onto the prepared tape.  This foam roller will wear and lose it's effectiveness after a year or two.  How do you know the time has come to replace it?  You start missing splices.

The following solutions apply to a zero-speed splicer

Problem: Rollers not set properly on vacuum roller.
Solution:  The roller that holds the prepared splice must be set at the correct distance from the running web.  This is and adjustable setting and must be maintained.

Problem:  Not enough vacuum.
Solution:  At the moment of the splice, if there is not enough vacuum, the splice will not attached properly.  The weight of the roll can also cause it to slide off the vacuum holes, especially if the roll is not evenly weighted.  Ensure there is enough to hold it firmly and let the roll settle for a bit before securing it to the vacuum roller.

Problem:  Knife is not cutting running web properly.
Solution:  Over time these need sharpening.  Ensure they are razor sharp.

Problem:  Roll is not aligned properly on splice.
Solution:  A sure sign that this is the case is if you see bits of splice tape stuck to the edges of the festoon rollers.  Be present at every splice to line the roll up properly.

I can't find my problem.
Start Over :Web Press Troubleshooting Guide

No comments:

Post a Comment