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Passivate

We are looking to start our own passivation process. What would we need in order to get started and is there any procedures that we should follow? Most items that are to be passivated are 316 stainless steel.

Billy Hawkes
instruments - Trevose, Pennsylvania, USA
2001

Hello Billy!

Take a look at letter 2030, below- it notes a few things on passivation. You'll also want to read the FAQs on this site. The baths are pretty straightforward, and I think AMS2700 and ASTM A967 are both good specs to use. I think there are citric acid passivation suppliers who frequent this forum, and they'll give you good advice should you choose to go the citric rather than the nitric route.

Good luck!

Lee Gearhart
metallurgist - E. Aurora, New York
2001

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2001

Billy:

There are lots of ways to set up your line depending upon the volume, size, etc. of the products that you are running. A typical line would consist of a bath with the passivation chemicals, two or three rinse tanks and a drying process.

The passivation bath is typically run between RT and 160F, with a pump and filter to keep the bath clean, and with ultrasonics if you want speed and super clean parts. The rinse tanks are typically backflowed to keep the final rinse very clean. The size and construction of the tanks depends on your product and your desires for volumes,speed temperature, etc.

Drying depends on size, shape and desire for speed. Hot air dryers are available, spin dryers, etc. Drying in a hot air dryer will accelerate the process dramatically and provide parts that are completely dry when packaging or storing them. If desired, parts can just be air dried at RT.

We agree with Lee Gearhart that it is easy to set up a safe, economical and high performance line with citric acid systems available on the market. There are excellent turnkey systems available.

Please contact us if you need help. We can set you up with a complete system, or help you to set up your own.

Regards,

Lee Kremer
Stellar Solutions, Inc.

McHenry, Illinois