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Conversion of Class flange and PSI flange, and comparison of pressure levels of common flanges 2021/01/13 21:46:13

Conversion of Class flange and PSI flange, and comparison of pressure levels of common flanges

The most commonly used flange standards in the pipeline industry are the ANSI series, including ANSI B16.5, ANSI B16.47, AWWA C207 series, including BACKING FLANGE(BACK RING FLANGE), HUB FLANGE and AWWA C228 stainless steel series, EN1092-1 series, EN series. In addition to the four most common standards, there are JIS standards, BS standard,AS Australian standards, GOST Russian standards and South African standards.

In all these standards, forged flanges are classified according to their rated working pressure according to the designed pressure. Generally speaking, there are 7 levels: CLASS150, CLASS300, CLASS400, CLASS600, CLASS900, CLASS1500, CLASS2500. Normally, people would say "a 300-pound flange" instead of "a CLASS 300 flange". This is just a non-standard customary nomenclature. However, you must remember that a class 300 flange does not mean that the flange is rated at 300 psi. The formula is:

PT = Pr ST / 8750

PT = the rated working pressure of the specified material at temperature T, psi

Pr = pressure rating index

Allowable stress of flange material at temperature T, psi

 

According to experience, at ambient temperature, the maximum operating pressure of X-type carbon steel flanges is about 2.4 times. This rule is especially applicable to grades of 300 or higher. For example, at ambient temperature, the design pressure of a grade 300 carbon steel flange is 2.4 x 300 = 720 psi.

 

For the conversion of CLASS and PN, please check the EATHU technical webpage or blog, and please contact EATHU sale team or download the PDF of various flange standards from eathu homepage www.eathu.com


ASME B16.5

ClassWelding neckSlip onSocket weldingThreadedLapped jointBlind
CL150(PN20)1/2"- 24"1/2"- 24"1/2"- 3"1/2"- 24"1/2"- 24"1/2"- 24"
CL300(PN50)1/2"- 24"1/2"- 24"1/2"- 3"1/2"- 24"1/2"- 24"1/2"- 24"
CL4001/2"- 24"1/2"- 24"1/2"- 3"1/2"- 24"1/2"- 24"1/2"- 24"
CL600(PN110)1/2"- 24"1/2"- 24"1/2"- 3"1/2"- 24"1/2"- 24"1/2"- 24"
CL900(PN150)1/2"- 24"1/2"- 24"1/2"- 3"1/2"- 24"1/2"- 24"1/2"- 24"
CL1500(PN260)1/2"- 24"1/2"- 2-1/2"1/2"- 2-1/2"1/2"- 2-1/2"1/2"- 24"1/2"- 24"
CL2500(PN420)1/2"- 12"--1/2"- 2-1/2"1/2"- 12"1/2"- 12"


ASME B16.47 A (MSS SP-44)

ClassWelding neckBlind
15026"- 60"26"- 60"
30026"- 60"26"- 60"
40026"- 60"26"- 60"
60026"- 60"26"- 60"
90026"- 48"26"- 48"


ASME B 16.47 B (API 605)

ClassWelding neckBlind
7526"- 60"26"- 60"
15026"- 60"26"- 60"
30026"- 60"26"- 60"
40026"- 36"26"- 36"
60026"- 36"26"- 36"
90026"- 36"26"- 36"


AWWA C207

ClassSteel-ring flangesSteel-hub flanges
B (86psi)4"-144" (DN100-3600)-
D (175-150psi)4"-144"(DN100-3600)4"-96" (DN100-2400)
E (275psi)4"-144" (DN100-3600)4"-96"( DN100-2400)
F (300psi)4"-48" (DN100-1200)-


EN1092.1

PNPlate (type01)Slip on (type12)Weld neck (type11)Threaded (type13)Blind (type05)
2.5DN10-4000DN10-4000DN10-4000DN10-4000DN10-4000
6DN10-3600DN10-3600DN10-3600DN10-3600DN10-3600
10DN10-3000DN10-3000DN10-3000DN10-3000DN10-3000
16DN10-2000DN10-2000DN10-2000DN10-2000DN10-2000
25DN10-2000DN10-2000DN10-2000DN10-2000DN10-2000
40DN10-1600DN10-1600DN10-1600DN10-1600DN10-1600
63DN10-1200DN10-1200DN10-1200DN10-1200DN10-1200
100DN10-500DN10-500DN10-500DN10-500DN10-500
160--DN10-300--
250--DN10-300--
320--DN10-250--
400--DN10-200--


Please check eathu flange product page for dimension, weight list and price list, if you can't find the information you need, please contact eathu sale team.

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