Methylene chloride vapor is normally used in the process for PC. The vapor is
created by heating a container with methylene chloride to the boiling point.
The parts are exposed to the methylene chloride vapor for less than three
seconds. The whole process must be performed in a closed and well ventilated
room, that prevents the operator from coming in contact with the fumes. Parts
must not come in contact with liquid methylene chloride.
After the polishing process, parts must be allowed to dry, in order to
evaporate the methylene chloride.
Finally the parts are gradually heated in an air circulation oven and kept at
120 ºC (250 ºF) for one hour to release surface stresses and to evaporate the
entrapped methylene chloride.
Dirt particles and all foreign matter, such as oils and greases should be
removed from the parts by carefully
cleaning and drying before polishing.
Because of the risks involved, this process must only be performed by an
experienced person. The chemical vapors are harmful if inhaled; special
equipment must be employed to avoid that the operator comes into contact with
the chemicals. In addition, various government agencies have strict
regulations concerning the exposure limits to this group of chemicals. Please
refer to the MSDS provided by the chemical supplier.
