Trim material A105 or WCB hardfaced with stellite

[engmazing]

Could someone help me with the question below?

Is it acceptable, as alternative, carbon steel (A105 or WCB) hardfaced with stellite instead AISI 304 or AISI 316 in trim's valves?

I've faced a problem with a chinese manufacturer: I requested these trims types: AISI 410/STL, AISI 304 and AISI 316. Obs.: All shells are A216 WCB.

However they provided all trim's in A105 or WCB hardfaced + stellite. Have experienced something similiar to it? I would be very grateful for opinions.

 

[anand25111987]

Hi diegoverly,

Assume your requirement is for a gate valve according to API600 spec. API 600 spec trim chart classifies the AISI410 steel as TRIM 1.If the seat surface is hardfaced with stelliting
and the gate surface is 410 then it is acceptable according to API600. But end users like Saudi Aramco accepts the TRIM material to be atleast equal to the parent body material. The required trim material can be overlayed on the seating surfaces( like your vendor has proposed). You need to refer the users specification for more clarity.

Thanks ,
AP

 

[engmazing]

Thanks for help.

The user specification is:

AISI 410/STELL for steam, AISI 304 for hydrocarbons in H2S services and AISI 316 for hydrocarbons in H2 services.

 

[Roberto1956]

Pay attention to last edition of API 600 that void the TRIM 1. The reason is galling problem caused by two stainless steel faces under great face contact pressure. Some manufactures are offering a upgrade of API 600 specially if you are buying a valve with API stamp.

 

[CKchi]

Hi Diegoverly,
This reply may be late, i assume you are talking about GGC vavles.

AISI 410/STELL - Trim 8; F304- Trim 2, F316- Trim 12.

I am working in a Neway, a chinese valve company, i would say it's common to trim in A105 or WCB hardfaced + stellite to prevent galling.
For example if trim F316
Body: WCB
Stem: F316
Seat: A105N + STL.6