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Ultraseal vs Zinc Chromate

We have meen having our hardware coated with what is being called "Ultraseal". A potential new supplier has access to what he is calling "Zinc Chromate". I don't understand the difference and would like an expert's comparison.

Wayne Mick
Manufacturer / Plating purchaser - Arthur, Ontario, Canada
June 3, 2008

Hi, Wayne. Ultraseal is a trade name for a final sealing step after zinc plating and chromating. In another context Ultraseal means the entire process of zinc plating, chromating, and sealing. Theoretically, a process which includes this sort of extra step should produce more corrosion-resitant parts than just zinc plating and chromating. So, in theory, a process that lacks the final sealing step may not be adequate (then again it may, some chromates don't need or benefit from final sealing). But we cannot compare specific proprietaries to other proprietaries or to generic processes here.

The main problem is that it is your company's job (your designer's job) to specify exactly what finishing processes you need. This can certainly be done by retaining a consultant to develop specifications for you, and it can possibly be done by your designer spending some time with people from several different shops to become better versed in how to write the specification. But, unfortunately, nobody from this distance will be able to advise you whether zinc plating (to no particular spec), followed by chromating (to no particular spec) offered by a shop with whom we are not familiar, will meet the actual needs of your hardware with which we are also not familiar :-)

Good luck and Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
June 3, 2008