Summary for chain cleaning cracks Discussion
Yellow zinc passivation on chain coupling parts is being blocked by residual oil, but longer cleaning times are causing cracks in the chain plates. Amit Y. Nangre explains that the chain is a 5/8" duplex chain used in flexible couplings, and that cleaning in cyanide or chromate baths does not fully remove oil; if the chain stays longer in the bath, cracks appear soon after plating. The reply advises first clarifying the cleaning method, asking whether the process is only degreasing or includes electrolytic cleaning. It also warns against using cyanide-based cleaners because they are hazardous to people. As an alternative pre-cleaning step, the answer suggests cleaning the chains with a 50/50 diesel and kerosene mix before chemical cleaning. The thread does not give a complete final process, but it points to safer pre-cleaning and better process control to avoid both poor plating and cracking.
2006
Dear Sir,
We are a flexible coupling manufacturer in India. We manufacture various types of flexible couplings one of them is chain coupling. In the chain coupling we manufacture we use a 5/8″ duplex chain.This chain is coated with yellow zinc passivation.
We have basically two problems:
No.1 – Before we plate the chain we have to clean the oil on the chain.We tried cleaning the chain in cyanide bath also in chromate bath but the complete chain does not get cleaned and if we keep the chain for longer time in the bath then the cracks develop. After few seconds of the plating of the chain cracks develop in the plates of the chain.
No.2 – To avoid the crack we do not wash the chain in the bath for longer time and go ahead with plating.But in the regions where the oil remains in the chain it does not get plated.
Can you please let us know what procedure should we follow to avoid both the above problems.
With regards,
Amit Y. Nangre
Dear Mr. Amit,
You have not mentioned your cleaning process , you are doing only degreasing or any electrolytic cleaning? please mention that, do not use cyanide base chemicals for cleaning it is very much hazardous for humans.
Or you do cleaning of chains with diesel& kerosene 50/50% before going for chemical cleaning.
Vishwas Nangare
motorcycle accessories mfgr.
– Aurangabad, Maharashtra, India
2006
Q. Hi I am having the same problem, the zinc starts cracking five minutes after plating process.
We don’t do any electrolytic cleaning, do you have any suggestions?
Omar Reyes
June 19, 2012