Coater blanket

Hi All,
can anyone shed light on why the coater blanket on XL75 picks up quite a lot of ink. We run with medium weight anilox an have the pressure backed of until just kissing, ink is building up and we get 2 heavy horizontal strips that are thick.
Any ideas are appreciated.

 

Hi! You can pictures to post? What anilox you have?

 

Sometimes we experience that if there is a light film of coating on the blanket while there's a lot of ink coverage on the job. Increasing the flow of coating % usually alleviates the issue.

 

That cannot be done on an anilox roller equipped machine, the only way to increase / decrease the coating is to change the actual anilox roller.

 

do you monitor the flow of your coating with a Zahn cup before pumping it up to your coater? Id begin with that and then if the problem persists id be looking at your annilox roller for clogged cells and also if its the right roller for what your trying to do.

 

Few possible causes...

Coater activating late, allowing ink to transfer to
coating blanket at start-up.
• Excessive pressure between blanket roll and
impression roll causing squeeze out of coating
and pick up of ink on blanket
• Insufficient amount of coating being carried by
blanket.
• Ink volume too great for single station
application or to allow sufficient bodying before
coating application.
• Ink tack too low, producing a weak strength ink
film.
• Excessive water pick up from fountain solution
by ink causing extended open time and ink film
weakness.
• Coating not rewetting properly.
• Blanket too soft or tacky due to having been
washed repeatedly with petroleum solvent.
• Improper blanket cleaning or possible
contamination.

 

Yes I would agree with that
If you are backing the pressure off the blanket to impression cylinder,
are you setting the pressure of the anilox roller to blanket?
is the under packing correct, is the blanket thickness correct?
if you are using under blankets is it fitted correctly should be white side up black to impression cylinder,
what consumables are you using? cheap blankets and coating may be causing your problem.
are you using the clean off facility at the end of the run?
is the anilox roller clean how often do you send it away for cleaning?

 

Thanks for all the help, will investigate the possibilities.
Regards.

 

if the suction pipe is not sucking the coating well or the coating have finish

 

Just a thought it is some thing we had a long time ago have you changed the Anilox roller?
If you have you gone from light roller to a solid roller the bearings may not be designed for the solid roller as it is heavier and can cause some wear which could show up as some ovulation which could possibly show up as lines on the blanket?

just thought!

 

Thanks Ade.