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Plating Testing / Verification

Hello,
I work for a company that is a distributor for industrial casters and wheels. One of our customers does a great deal of business in Europe and all of the casters that we supply to them must conform to the European RoHS (Reduction of Hazardous Substances) initiative. It is my understanding that how RoHS effects casters basically has to do with the chemicals used in the plating process. Plating which uses Hexvalent Chromium is not allowed, where as Trivalent Chromium plating is acceptable. My question is this: Is there a method of testing a finished product that can identify the particular type of plating used on that product and what type of company should I go to for this type of service? I am searching for a way of verifying that the plating on the product we receive from our manufacturer's in China & Korea are indeed Trivalent Chromate plated and not Hexavalent Chromate plated. Right now we simply have to take the manufacturers at their word and there are many unscrupulous caster manufacturers overseas that are less than truthful. Thanks for your help!

Mike Cooper
Buyer & Inside Sales - Indianapolis, Indiana
August 28, 2009

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September 3, 2009

Mike,

RoHS is about the final product, not about how you get there. So if you chrome plate from a hexavalent solution and then verify that all of the hexavalent chromium has been removed before delivery then the parts would be RoHS compliant as the chromium would be in the metallic zero valent state. If you plate from a trivalent solution the result is the same in that you will be delivering metallic chromium in the zero valent state, not the trivalent state.

However when we talk about hexavalent and trivalent passivation of zinc plating then RoHS does apply. If you use the hexavalent passivation there will be hexavalent chromium on the final product. In this case you do need to use the trivalent passivates.

Hope this goes some way to clearing up the confusion.

Brian Terry
Aerospace - Yeovil, Somerset, UK