Source of web breaks: Rollstand, flying paster or infeed.
Problem: Poor Paper Quality
Solution: Try a different position on the jumbo or a different paper altogether.
Comments: Though it is hard to see, when the paper rolls are weak, this will generally show up right away in the beginning of the web press. Check the edges of the roll. Paper defects are common. Sometimes nicks can occur or the slitter at the paper mill was simply dull. Also, hold the paper up to the light and check for pin holes.
Problem: Foreign Material On Idlers
Solution: Clean off idler rollers. Carefully check each one for dents that could cause a raised spot and break through the web.
Comments: Generally a splicer can have two sided tape build up on the idlers. Splice after splice can cause this buildup. Or perhaps a pieces of tape wrapped around the roller to take out wrinkles. Whatever the case, check the idlers carefully for any raised spots on the idlers from buildup or damage.
Problem: Excessive Tension
Solution: Lower tension
Comments: Some papers cannot handle higher tension. Lower your tension as much as possible before it begins to wander. If breaks are happening after the infeed, your screwed. You may have to reject the paper.
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