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Selection of coating process for 10 year life on brake solenoids

I work for company which uses brake solenoid for vertical transport solution equipment. Brake solenoid is expected to work under following conditions: Max temp surrounding plungers is 130 °C, high relative humidity of 94%. Presently we are using hot dip galvanizing for low carbon steel plungers which reciprocate on opening and closing of solenoid. Salt spray test results indicate generation of white rust after 8 hours. Plating thickness varies from 0.008 to 0.012 mm. Pl. suggest whether 1. Plating process and thickness selected is correct for application where Solenoid is expected to work for at least 10 years without generation of white rust.

Prashant M.
Brake solenoid - Thane, Maharashtra, India
2004

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Dear Mr Prashant,

You are probably using a simple zinc plating with Blue Passivation. You may want to look at Zinc - Iron Alloy plating if you desire a 10 year service life.

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

2004