Elongation

[Jose]

How many have to stretch a blanket when you put it in a press???? 1 milimeter, 2 milimeter .... after you tensile it.
thanks

 

[Kaoticor]

Sorry, I am not understanding your question. Can you provide more detail? Thanks,

K

 

[Cornishpastythighs]

When you install a blanket you should always use a Torque wrench and tighten up to Manufacturers specs. Run the blanket in for a few sheets and then re-torque. Blankets usually stretch out of spec because a gorilla with a wrench overtightens the blankets which results in blanket stretch, Register/fit issues, blanket caliper loss(Squeeze) or just plain ripping the buggers out of the bars. Always a good idea to check tightness once per week with a torque wrench.

 

[Alois Senefelder]

Blanket Tension

Blanket Tension

Jose,

By tensioning the blanket we elongate ( stretch) its length.

The task of tensioning is to make the blanket, which is made from compliant materials,
become an integral part of the cylinder to which it is wrapped round.

This is why blanket torque setting is an important technique in achieving the -
Correct Ink Transfer via Plate/Blanket/Impression Cylinders.

One more important setting is the - Blanket Height above or below the Cylinder Bearers.

Regards, Alois

 

[tkemerly]

May also want to consider that folks are now sometimes replacing the packing paper with mylar/perma-pack. I think that the blankets are more prone to movement thus effecting register at the tail. The Operators solution is to apply even more torque.

I would not use mylar/perma-pack on the blanket cylinder at this point, it is hard and as well takes away some more of the ability for the blanket to take a hit without smashing.

OMO....

 

[tkemerly]

How many have to stretch a blanket when you put it in a press???? 1 milimeter, 2 milimeter .... after you tensile it.
thanks

The type of backing on the blanket can effect this considerably... Some blankets have a nylon type weave placed into the backing to help resolve the fan out register at the tail...

OMO...