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  for Metal Finishing since 1989
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Pitting problems in aluminium

Hi everybody,

I have a problem with a problem with the result from bright dip. The metal is pitted everywhere around the metal. it is only a light pit but covering the whole aluminium. I am not sure the cause of it. However, we solve the problem by rinsing the alkaline cleaner with alkaline rinse and goes into a desmut tank before going to the bright dip tank. Normally, the alkaline cleaner is washed off in the hot rinse that is used to washed the bright dip. so the hot rinse is used as a common rinse. I suspected that it might be the problem as it is used as a common rinse tank. However the problem only arises after approximately 10 months of the usual process. If it is the rinsing tank, it should create the problem from the start. I also suspected the alkaline cleaner and the metal but I am not sure why? can anybody advice me on this problem.

Thank you very much.

Joe Yefrey
- Melbourne Australia
2002