Carbon steel fittings stay cost-effective when the coating matches the real environment. Over-specifying nickel on an indoor oil line wastes money; under-specifying zinc outdoors creates rust claims. This article is a practical plating pick list for OEM buyers.
See production examples in carbon steel pipe fittings. If corrosion risk is high, compare stainless steel pipe fittings before you force a heavy coating onto carbon.
Zinc plating
Still the default for many adapters and plugs. Define clear vs yellow and any salt-spray expectation. Remember plating thickness can affect external threads — machining allowance matters.
Electroless nickel
More uniform on complex geometry and useful when wear plus corrosion both matter. Cost and process control differ from barrel zinc; call it out early on the RFQ.
Black oxide and oil
Fine for indoor appearance and mild protection, not a coastal coating. Be honest about storage and shipping humidity.
RFQ wording that helps
Write media, indoor/outdoor, washdown, and target tests. Send the print through Contact. Broader process context lives on OEM / ODM and in our factory notes.
Frequently asked questions
01Can plating replace stainless?
Sometimes for mild environments. Not when chlorides, washdown chemicals, or bare corrosion rules dominate.
02Should threads be gauged before or after plating?
Follow the print and quality plan. Many programs machine with coating allowance and verify after finish on critical externals.