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Electro-Zinc Plating and Passivate Plating

2004

Hello,

My Company produces strapping system, which need roller conveyors to transport bundles. At present we use electro-Zinc plating for those roller finishing. It's cheaper. Our problem is that those rollers have "finger prints". It shows at first as "yellow", later on it turns to "black". I was told that if we do "passivate plating" treatment would solve the problem. Is that right? If it is right, then what about the price?

I appreciate if anyone could help me about it.

Regards,

CARRIE LIU
- WHITBY, ONTARIO, CANADA

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I have to make a few assumptions since your question didn't mention them. First, that the parts are either clear chromated or not chromated at all. Second, that the parts are not like that when they are received. This is a common problem with larger zinc plated parts since the surface is so active and easily stained. Passivating the surface is usually not necessary if the parts are rinsed properly and a good chromate is applied. If possible, switch to a yellow chromate. If not, a good blue-bright(clear) chromate and a sealer will give you longer life before the zinc starts to turn. Also, it's always a good idea for employees to wear clean gloves when handling the parts from the plating cycle to assembly.

Jim Conner
Anoplex Software

Mabank, Texas USA

2004