Boiler Feedwater Valve Material 1

[JNieuwsma]

Hi folks,

I haven't had any luck with this query on the Valve forum, so I'm hoping some of you B&PV people can help out...

I've come across a requirement for valves of "WB36" steel, specified for a boiler feedwater system at 200 deg. C/30 MPa (approx. 390 deg F/4350 psi). Never having heard of WB36 I did some research and determined that it's a DIN material (EN 1.6368), with no "direct" ASTM equivalent as far as I can tell.

FYI, specified chemical and mechanical properties of WB36 are as follows:
C 0.10-0-17
Si 0.25-0.50
Mn 0.80-1.20
P 0.025 max
S 0.020 max
Cr 0.30 max
Ni 1.00-1.30
Cu 0.50-0.80
Mo 0.25-0.50
Nb 0.015-0.045
N 0.020 max
Al 0.015-0050

Yield 430 N/mm^2 (62 ksi)
Tensile 580-740 N/mm^2 (84-107 ksi)

Questions:
1. To confirm my finding, is there no direct ASTM equivalent of WB36 material?
2. What ASTM material is generally specified for such an application?
3. Any other relevant comments or suggestions?

Thanks for the assistance!
Jonathan Nieuwsma

 

[davefitz]

most cast carbon steel valves are WCB.

 

[JNieuwsma]

<<most cast carbon steel valves are WCB.>>

Or WC6 or WC9 for higher temperatures, but in this case a Class 2500 WCB valve would seem acceptable to me. But the equivalent DIN material (No. 1.0619 or EN10213-2)was not specified; maybe there's something special about WB36?

JN

 

[unclesyd]

There appears to be no ASTM equivalent for 15NiCuMoNb5 (WB36). It falls between F12 (WC6) and F22(WC9). There is also some concern about it's in service embrittlement, due to copper precipitation.
Looking at the tables it is strong though somewhat limited in service temperature 450&#778;C .

I don’t see it except as a forging.

Check the following link.

http://www.tycovalves-na.com/ld/RAILT-0007-EN.pdf

 

[ruth44]

I have a Mannesmann data sheet for WB36It is in German and dated 1972. It lists chemical and mechanical properties as well as recommendatîons for application etc.
If it helps you I can email it to you.

Ruth44