Galling between AISI 316 And Duplex J92205

[Erkamal]

Hi Friends,
i am working in valve industry.
my valve body is duplex casting. so what material of stud and nut will be used to preventing galling on high temperature service.
ASTM 194 & 193 are ok???

 

[TVP]

What is your definition of high temperature service?

 

[Erkamal]

Hi Frd,
it will go up to 130 deg.C. but i am more interested in galling issue.

So wol galling problem come in combination of AISI 316 to duplex?

 

[tbuelna]

Why would galling be an issue between your stainless steel valve body casting material and a stud/nut made of some other stainless steel alloy? I would assume the stud gets installed in the housing once and is never removed under normal conditions. That's the reason for using a stud, right?

As for a stainless steel alloy that is resistant to galling to use for the stud and nut, A286 would be a good choice.

 

[Roberto1956]

The studs and nuts need not be resistant material as the valve body unless the enviroment make it necessary. In this case you need to use stainless steel stud and nuts. To avoid galling some companies made surface treatment. I don't remember exactly the trade name but it was something similar to SHILAN and it was blue. gO TO THIS SITE AND i BELIEVE YOU WILL BE CLOSER TO IT:

http://www.praxairsurfacetechnologi...10460_SermaGard_coating_systems+protected.pdf

 

[Roberto1956]

I met this site in internet:

http://www.unbrako.com/xylan4.htm

Look at: Xylan 5214: Low friction, corrosion resistance, anti-galling (stainless steel) for fasteners. (suitable for bulk processing).