Page 47 - Training 2019

If the roll lacks a dead band, ink will build up there and contribute to end
seal failure. Chips on the ends of the anilox rolls can also create ink build
up and compromise the integrity of the end seals.

Doctor blades that are too short or too long can be another source
of leaks.

When changing a doctor blade, it’s important to make sure that the new
blade is the right size for the chamber and installed correctly. Typically,
the blade should come to about halfway across the tops of the flexo end
seals when placed in the chamber. If the blade does not reach the seals,
then the seals can actually prevent contact between the doctor blade and
the anilox roll. If the blade extends beyond the outer edge of the end
seal, it may create a small opening between the underside of the blade
and the end seal which creates a path for ink to flow out of the chamber.
This is more prominent on thicker blades. If it’s too long, the blade may
also become wavy and not lay flush with the roll, causing uneven
metering and leaking.

Many new chambers come with special moulded rubber seals.

These can be very effective but also very expensive. Sometimes more
traditional flexo end seals can be substituted with good success.

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CHAMBER BLADE END SEALS TRAINING MANUAL
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Updated - 24 June 2019