ASME Section IX: QW-151.3 Question

[newweldeng09]

A 1.5 inch plate was tensile tested using turned specimens. Two .500" diameter specimens were pulled for each required set. Does one more specimen have to be pulled representing the full thickness of the test coupon?

 

[jwhit]

If the machine shop laid out the test plate correctly you should be in compliance with QW151.3(b)as long as your grip end is not greater than 1.25" in diameter and they took one sample from the root side and one from the face side. In my experience with .505 rounds they will machine a .75" diameter threaded grip from a 1" square which puts the specimen center at 1/2" from the surface.
I've found that it usually helps me if I sketch these things out and include the layout with the PO to the testing facility. I make the assumption that everyone around me is also spatially challenged thus needing it on paper.

 

[metengr]

Yes, this is acceptable based on Table QW-451.1, 2 tension tests are required followed by Note (2) requirements for details on multiple specimens.

 

[newweldeng09]

Thanks. If the tensile tests were taken in accordance with QW-151.1 (Reduced Section-Plate), then 3 test specimens of 1/2" thickness would be required for each set. Is this correct?

 

[metengr]

Correct. The information in QW-151 are specifics regarding specimen size - either full thickness coupon per tension test or if your tensile test machine cannot handle full thickness, smaller size specimens are permitted as long as they represent the full thickness.

 

[newweldeng09]

Thanks again. It seems that when using the turned specimens as mentioned above, a 1/2" of material is missing from the tensile tests in the welded area, based on the design of the turned specimens. But when using reduced section plates the entire thickness of the weld is evaluated. Why does ASME accept the turned specimens as an acceptable form of tensile testing?