The ink pumping management and wash-up systems are designed for its proper delivery and effective cleaning into the flexographic printing units.
These units integrate a pumping system carrying the ink from its pail to the printing unit and provides a proper control of its correct flow in and out of the applicator head. It grants ink flow consistency and proper pressure control in order to avoid over-pressure, air bubbles formation, and splashes.
In support of ink change operations, the system enables used inks evacuation from the circuit and its recollection in the original pail, subsequently it cleans the circuit in order to prevent the new ink to be contaminated.
The proper cleaning of the inking circuit, including pumps, pipelines and applicator heads, is achieved by flowing a washing liquid adequately chosen in accordance to ink characteristics (solvent, water, combined thinners) and using certain functions in sequence.
The basic wash-up sequences are:
Ink draining from the complete circuit;
Washing product flow into the circuit;
Draining of the washing product.
Each operation is carried out with different methods and time frames, depending on type, level of cleaning action and the ink features.
The type of washing products, their quantities and level of purity obviously influence the level of contamination left. However, in order to reduce quantities usage, some washing products can be recycled for a preliminary washing cycle.
With the automatic wash up system, washing sequences are controlled by a microprocessor. The wash-up cycle is operated with sequences and time frames already pre-set in a program. However, some of the parameters can be altered, independently for each printing unit, by accessing a set up function and can be recorded with a job code (recipe) re-usable at operator’s option. Wash up cycles are activated simultaneously, for all printing section pre-selected, with their individual parameters’ settings. This system allows precise personalized sequences replication resulting very effective with the use of different inks and thinners.