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Ted Mooney, P.E. RET
Pine Beach, NJ
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for Metal Finishing since 1989
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Electroless nickel plating on SS 316 ball valve
August 15, 2011
dear sir
we need electroless nickel plating on SS316 ball vales of size about 1.6 meter diameter.
the problem is we don't have any idea about this plating process, equipments and chemicals.
so please send me the details about this plating process with the equipments .
Employee - Mumbai, Maharashtra, India
August 17, 2011
What you ask for would take pages. There are complete books on the subject as well as chapters in general books.
There are lots of problems with electroless plating an object that large. There is zero way that I would start out electroless plating on that part. Get some experience first on smaller parts. The cost of having a boo-boo on an EN tank that large is huge! Nickel is currently expensive to plate and there are a lot of things that can go wrong.
Another option is to get a highly qualified consultant that has actually EN plated ball valves that large to come in , set up the process and train all of the people.
- Navarre, Florida
August 19, 2011
I strongly recommend patented EN chemistries because they are far more efficient, give more consistent results and include technical support from the vendor. But if you want to go the "cheap easy way" a generic formula for acid electroless nickel follows:
20g/L nickel sulphate
25g/L sodium hypophosphite
30g/L lactic acid
2g/L propionic acid
1 ppm lead as stabilizer.
Ammonium hydroxide to pH 5
Only distilled water and premium quality chemicals.
Temperature 90° C
Frequent additions of chemicals are required to compensate reaction losses. By-products accumulate over time and interfere with quality of deposit and speed. At a certain point the bath becomes inoperable and has to be discarded.
The deposition takes place without (LESS) electric current over catalytic surfaces (i.e. steel, nickel). The deposit is a solid solution of around 90% nickel+10% phosphorous about 450HV as plated and hardenable up to 850-900HV. When the bath is new it should plate 0.001" /hour. Stainless steel is NOT catalytic, so it has to be properly activated in a Woods strike bath.
Good luck,
G. Marrufo-Mexico
Monterrey, NL, Mexico
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