Out of Roundness Definition ASTM A358

[slb210]

Hello,

I’ve seen out-of-roundness defined various ways depending on the standard. Can anyone please help me interpret the out-of-roundness per ASTM A358 (Electric Fusion Welded Stainless Steel Pipe) stating:

“Out-of-Roundness – difference between major and minor outside diameters, 1%.”

Is this similar to ASME Sec VIII Div UG-80; where Out-of-Roundness is defined as: (Major Outside Diameter – Minor Outside Diameter) / Nominal Outside Diameter?

 

[EdStainless]

Well nearly, the math is almost identical.
In A358 you are dividing by the average, and in UG-80 you are dividing by the specified outside diameter.
I would hope that they would be the same in the end.

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P.E. Metallurgy, Plymouth Tube

 

[slb210]

This helps, thank you for the clarification!