Annex A API 650 Thickness formula
Annex A API 650 Thickness formula
(OP)
Hello everyone,
I have a question regarding the value of 145 used in thickness formula in Annex A of API 650.
In the thickness formula of annex-A of API 650, a constant value, of 145 mPa, is used instead of allowable stress of a particular material. For material, like A-36, which has allowable stress more than 145 mPa, this approach is understandable, but what about material like 283 Gr C, because allowable stress of 283 gr C is 137 mPa, WHICH IS LESS THAN 145.My question is should I use 137 instead of 145 in the Annex-A thickness formula or not?
Regards,
Inam
I have a question regarding the value of 145 used in thickness formula in Annex A of API 650.
In the thickness formula of annex-A of API 650, a constant value, of 145 mPa, is used instead of allowable stress of a particular material. For material, like A-36, which has allowable stress more than 145 mPa, this approach is understandable, but what about material like 283 Gr C, because allowable stress of 283 gr C is 137 mPa, WHICH IS LESS THAN 145.My question is should I use 137 instead of 145 in the Annex-A thickness formula or not?
Regards,
Inam





RE: Annex A API 650 Thickness formula
RE: Annex A API 650 Thickness formula
A.1.3 This Annex is applicable to any of the Section 4 materials, although the single allowable stress does not provide any advantage to higher strength steels.
However, that does not address the OP's question - why is the Annex A allowable stress greater than the tabulated product allowable stress for A283 material? Is it just that Annex A is so conservative that the 137 vs 145 is essentially rounding error?
RE: Annex A API 650 Thickness formula
Otherwise, just a quirk in the code generation process.
RE: Annex A API 650 Thickness formula
RE: Annex A API 650 Thickness formula
RE: Annex A API 650 Thickness formula