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API Spec 6A Tensile Test Yield Offset Requirements. Tim Haeberle API SC6 2012 Summer Meeting. Background. PROBLEM: The yield strength acceptance criteria for bodies, bonnets, and end and outlet connections is limited to the 0,2% offset method yield strength values in Table 6. This is good!
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API Spec 6A Tensile Test Yield Offset Requirements Tim Haeberle API SC6 2012 Summer Meeting
Background PROBLEM: • The yield strength acceptance criteria for bodies, bonnets, and end and outlet connections is limited to the 0,2% offset method yield strength values in Table 6. This is good! • However, for mandrel hangers it is up to the manufacturer to specify not only the yield strength in MPa (psi), but also the method of determining the yield strength. • Unfortunately, if the manufacturer does not specify the method of determining the yield strength, methods other than the 0,2% offset method may be used, and these may give higher or lower values than would be obtained if the 0,2% offset method were used. Need to fix in API version
The Solution PROPOSED REVISION: • 5.3.5.2 PSL 2 to 4 tensile testing (for mandrel tubing hangers and casing hangers) “b) test method: Perform tensile tests at room temperature in accordance with the procedures specified in ISO 6892-1 or ASTM A370. Perform a minimum of one tensile test. The results of the tensile test(s) shall satisfy the manufacturer’s specified requirements. The 0,2% offset method shall be used for determination of the yield strength”. JUSTIFICATION: • A standardized method of determining the yield strength needs to be used for mandrel casing and tubing hangers.
API Ballot • Ballot ready for SC6 to approve at the 2012 Summer Meeting for formal balloting
Background CURRENT WORDING • 5.3.5.2 PSL 2 to 4 tensile testing (for mandrel tubing hangers and casing hangers) “b) test method: Perform tensile tests at room temperature in accordance with the procedures specified in ISO 6892-1 or ASTM A370. Perform a minimum of one tensile test. The results of the tensile test(s) shall satisfy the manufacturer’s specified requirements.” • 5.4.2.3 PSL 2 to 4 tensile testing (for bodies, bonnets, and end and outlet connections) “b) test method: Perform tensile tests at room temperature in accordance with the procedures specified in ISO 6892-1 or ASTM A370. Perform a minimum of one tensile test. The results of the tensile test(s) shall satisfy the applicable requirements of Table 6.” • API 6A Table 6, column 2 (for bodies, bonnets, and end and outlet connections) “0,2% offset yield strength”.