brass fittings on stainless steel

[tjagiello]

Hi guys,

I recently got a stainless steel body rotary pump which has 3/8" NPT female connectors. I'm in the UK and I'm having quite a hard time finding stainless steel 3/8" NPT-BSP male/male adapters. Do you think it's ok to use brass ones instead? they are easily available, but I'm a bit worried they might corrode due to different types of metals used for the connection. The pump will be pumping fresh cold water @ 2-9bar and will be running for around 10min a day.

Regards,
Tom

 

[Cervantis]

We use brass and stainless as a standard connection all the time. One area does not have and never complains of leaks and the other area fights them all the time. The one area that does not have leaks uses SS and brass, while the other area does not consistently use SS and brass. As for the corrosion, with brass that is not an issue or at least has never been shown to be an issue. Brass is soft, and the threads have a tendency to get "dinged" a bit in transport or in application. We deal more with the pitch diameter on brass due to where we get the product from. Most of our brass finishes early and does not give us the number of engagements we would like to see. But that is a supplier problem and not a material issue.

 

[Cervantis]

I might also recommend looking at the forum for Materials Engineers under corrosion engineering for additional experience and thoughts.