Do Hastelloy C276 threads gall??

[Biggy]

Does any one have any experience of Hastelloy C276 threads galling, like stainless steel does?

Also does anyone have any data on the coefficient of friction for Hast C276 threads?

Thanks in adavance

Biggy

 

[INBCPE]

We had an aqueous waste water neutralization system in our plant that used Corcoran pumps (Hastelloy C276). I never understood why they had threaded connections, but they did. We never had serious problems with leaks, and these connections were right on the pump casing. Some of the casings were six or seven years old, and we used to tear them apart every six months to change seals. But I suspect that they do gall in clean service. In our case the joint threads (and every other leak exposed to air) quickly formed a tough salt barrier that kept the joint intact. You might want to pose this question to a metalurgist or supplier. The alloy suppliers are usually pretty helpful. You might even want to call Corcoran to get their position on the subject. Their number is 815-485-2156. Ask for Bill Kramer. Their model 4000D and 3000D pumps came in Hastelloy C276, and had threaded connections. If he asks for a serial number, give him #2838.

Hope that helps.

 

[Biggy]

Thanks for that.
I have been in touch with Haynes International and they have wear and galling data for their alloys and the simple answer is yes they do, but not to the same extent as stainless.

Biggy

 

[evelrod]

Biggy, based on my own experience and the fact that you often only get ONE shot at this---I would continue to use some form of lubricant. Perhaps a wax base in your case???


Rod

 

[Biggy]

Unfortunaltey I cannot use wax or 'ordinary greases' to chemical compatibility.

I am proposing to use a PTFE based grease (Fomblin or Halocarbon) to reduce the wear but, with all these sort of issues, the proposal is the easy bit. It is actually getting the approvals to 'try' it.

Thanks for the help.