CLEANING OF EQUIPMENT FOR OXYGEN SERVICE - AIGA

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AIGA 012/04
The chlorinated solvent is heated to its boiling point in the bottom of the vat with the vapour rising
upwards. The parts to be cleaned are immersed in the vapour phase in the lower part of the vat (the
vapour zone) where they are suspended during the cleaning process. The solvent condenses on the
surface of the parts, dissolving oil and grease, which drain off together with the solvent, which
accumulates in the bottom of the vat. The surplus of vapour is condensed on the cooled walls in the
upper part of the vat (the cooling zone). Remaining vapour, if any, is evacuated through slots just
below the upper edge of the vat.
This self-distilling principle means that clean solvent condenses on the parts even if the solvent in the
sump is heavily contaminated.
During the cleaning procedure parts with cavities must be turned upside down for emptying of
contaminated solvent.
The cleaning stops when the temperature of -the parts reaches the boiling point of the solvent. If this
happens before the parts are adequately cleaned, the parts have to be cooled down with cold solvent
before the degreasing process can proceed.
Vapour degreasing can be combined with ultra sonic immersion and spraying, usually in separate
areas of the machine.
Regular checks of the solvent in the sump according :o the solvent manufacturers recommendations
is necessary to ensure that the condition of the solvent) being used is always suitable for safe and
efficient use.
Special precautions are necessary including the requirement of entry permits into a confined space,
he use of suitable breathing apparatus and the wearing of protective clothing.
Applications:
Vapour degreasing can be applied to all kind of parts is the vapour can reach and condense on all
surfaces. Problems may occur for small and thin details which ire quickly heated up to the boiling
temperature.
4.2 Immersion Cleaning Machines with Non-Chlorinated Volatile Organic Solvents
A) Venting fan
B) Lid
C) Pump