Valve Class
Valve Class
(OP)
Would appreciate anyone's help. Thanks in advance.
If a valve is supposed to be say Class 800, what does it mean? I am sure it is related to pressure and temperature but do not know the exact meaning.
Also if I have a valve with known capability to handle a known pressure and temperature, how do I know what Class it is?
I guess both questions are related .....
If a valve is supposed to be say Class 800, what does it mean? I am sure it is related to pressure and temperature but do not know the exact meaning.
Also if I have a valve with known capability to handle a known pressure and temperature, how do I know what Class it is?
I guess both questions are related .....





RE: Valve Class
It's listed in the API 602. Per grade of materials are maximum allowable design pressures presented at different temperature levels.
Class 800 is applicable for Socket weld or Threaded end valves.
Success.
Regards, FKE
RE: Valve Class
A valve that has a WP rating, a working pressure rating, might not have a ANSI class designation. ANSI class designations apply to flanges (and flanges on valves), and are sometimes applied to compatible weld end valves (where basically the flanges are not welded on to the valve body).
For a definition of WOG (water, oil, gas pressure withstanding capability and is not related to fluid compatibility), see here,
http://www.nibco.com/showFile.do?fileId=1336
BigInch
-born in the trenches.
http://virtualpipeline.spaces.msn.com
RE: Valve Class
hope this helps
mark
RE: Valve Class
For WOG valves, typically, we use WOG 2000# and up. I don't recall seeing a WOG 800#, not to say they don't exist.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?
RE: Valve Class
Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada
RE: Valve Class
API STD 602 indicates that "Class 800 is not a listed class designation, but is an intermediate class number widely used for socketwelding and threaded end compact valves." Also "This International Standard is applicable to valve end flanges in accordance with ASME B 16.5 and valve body ends having tapered pipe threads to ISO 7-1 or ASME B 1.20.1. It is applicable to extended body construction in sizes and pressure designations of Class 800 and Class 1500, and to bellows and bellows assembly construction as may be adaptable to gate or globe valves in sizes. It
covers bellows stem seal type testing requirements."
RE: Valve Class
Didn't this exist?
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?
RE: Valve Class
They are welded and threaded ends, as per FKE.
ht
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?
RE: Valve Class
Section 1 of API 602 stated "Class 800 is not a listed class designation, but is an intermediate class number widely used for socketwelding and threaded end compact valves."
Section 4 of API 602 stated:
4.1.2 Interpolated ratings
Pressure/temperature ratings for Class 800 shall be determined by the equation: P8 = 1/3 P6 + 2/3 P9
where
P8 is the pressure at the specified temperature, expressed in bar3, for Class 800 rounded to the nearest
(10 kpa);
P6 is the listed pressure, at the specified temperature, for Class 600, expressed in bar;
P9 is the listed pressure, at the specified temperature, for Class 9004, expressed in bar.
RE: Valve Class
Patricia Lougheed
Please see FAQ731-376 for tips on how to make the best use of the Eng-Tips Forums.
RE: Valve Class
RE: Valve Class
Sounds like ANSI Class 800 is socketweld and the likes.
Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada