Page 41 - Training 2019

These are very important variables in determining the best seal for the
press.

It is of the utmost importance that all felt material be pre-soaked before
installing it in the chamber. When the felt is not pre-soaked, it will abrade
within minutes and create sealing failure. Most manufacturers of high-
quality enclosed-chamber end seals pre-soak felt seals prior to shipping,
eliminating any problems for their customer. Felt seals should be pre-
soaked in oil, generally for at least 15 minutes, then drained and left out
to saturate for a period of 24 hours. After the felt seals have been soaked
and saturated for 24 hours, all unused seals should be kept in a sealed
(air-tight) container or bag until ready for installation. This will ensure
that the seals maintain their sealing integrity.

Problem areas that are over looked:

Another more common harmful issue here is chips on the ends of the anilox
roller. Rollers get dinged and damaged while changing, cleaning, storing,
moving, or just by sitting innocently on a cart and having something else
banged up against them. We strongly recommend anilox blanket
covers; they can pay for themselves so quickly. These dings not
only carry ink up to the end seal causing build ups, they can
physically tear up an end seal rather quickly.

Inspect the anilox roller and point out the problem to the printer and advise
them that we can supply anilox blankets (covers) to protect their anilox
rollers.

Another area that needs to be inspected is their chamber blade unit. Have
a look at where the end seals fit. Is this area damaged or clogged with dry
ink or coating? If the end seal does not fit properly it will not seat and cause
leaks. Many of these areas are damaged when the operators try and chip
the dried ink off the aluminium frame. The picture below is an extreme
example of what can happen with leaking chamber end seals.

Anilox Roll Influence:

One of the most important factors in an end seal’s quality of performance
has nothing to do with its material. Believe it or not, the anilox roll can
determine whether a seal works or fails. Ink is forced out of the
microscopic anilox cells and is metered by the doctor blade. Cells in a
ceramic anilox roll should never be engraved on the end of the roll where
an end seal is riding. This causes the ink to be forced up onto the end
seal and slung onto the press frame, where it creates bad condi

CHAMBER BLADE END SEALS TRAINING MANUAL 7
Updated - 24 June 2019