valve material 3

[cbcarreon]

Can anyone help me tell the difference between valve material ASTM A352 LCB and A350 LF2? I requested for a quotation of a trunnion mounted ball valve with a body material of ASTM A350 LF2 operating at max 100 deg c. and not sour service. but instead i got a A350 LCB specs. Can i use this material specified by the vendor?

 

[gr2vessels]

One is casting, the other forging. The suitability of one or the other depends on many other things like trim, configuration, etc. Your specification however, is a bit confusing. Why would you specify LF2 material for relative high temperatures, when the ASTM A350 LF2 has been developed for low / criogenic temperature applications. If the low temperature is not part of your specification, it makes no difference which one are you using, they both are suitable, but not recommended for your application.
cheers,
gr2vessels

 

[tsenthil]

LF2 & LCB are basically same Low Temperature Carbon Steel, which can be used up to -49 deg C.

LF2 means forging and LCB is the equivalent Cast Version. Normally Forging version limited to 4". Above 4" Casting is much cheaper.

Whats the minimum design temperature? If it less than -29 deg C then you can use WCB or SA105.

 

[BValve]

It is correct that LF2 and LCB are equivalent while first is forged , second is cast.
Both can be normaly used (impact tested)from -46°C to max temp. as per respective ratings depending on design pressure.
LF2 and LCB are not considered as cryogenic grades which startfrom minus -46°C.

I guess your ball valves are flanged, if they have to be welded to pipe, be careful with material group of pipe (They are from different material groups as per conservative design code ASME B16.34 and have different max. carbon equivalent).

Finally, note that in europe where most high end valves are manufactured, A350 LF2 is the most common material for split body ball valves up to 60" size. Cast is commonly used for small sizes (one pattern, thousand of units, high alloy steels and top entry designs where weight saving is a must.

Regards.

 

[cbcarreon]

thank you guys! i really appreciate your feedbacks, you've been very helpful.

Best regards,