Urbanite 876 Upper Former issue

[lem]

Hey Guys,

Having an issue with a 2x 24in web configuration running into our upper former where the inside web is ripping, sometimes in half, as it comes off the nose of the forming board. The lower former has no issues with this though the webs to that board have a lot less distance to travel.

We've tried adjusting the nips and tension springs on the reelstand and are still having the issue. At the point where you can actualy hear it stop ripping the nip settings are too loose so that the lead heading down to the lower is walking side to side so that isn't working.

This is a 10 unit Urbanite with an 876 folder. 4 units stacked 2 high on the back end full color "s" wrap web and 6 units on the front end with 4 unit's stacked 2 high with 2 single units on the floor running just black for inside print content.

Anyone have any insight or previous experience with something similar as this? It is only the inside web that is ripping also, not the outside web.

 

[BeauchampT]

Have seen something similar on an older press. The bottom web would snap at top of former while starting up, and sometimes on run. Turned out it was the balance we had set between our former board air, silicone, and the draw nip settings below the former.

Have you tried reducing the tension on the former board by reducing the folder draw???

 

[lem]

It's looking like reducing tensioning via springs for that particular web/roll is the key along with reducing running speed quite a bit to reduce web wandering.

It seems that even with a small reduction in basis weight over the last few years along with our aging press there's not much else you can do. I hadn't run this config in quite a few years as I was daytime pressman and only dealt with the lower former. Consulting with a night journeyman led me to this solution.

Thanks for the the help none the less!