Difference between "elongation" and "computed elongation"

[maryam1979]

What is the difference between "elongation" and "computed elongation" in ASME Sec. II (e.g. SA213)? Can we use "computed elongation" instead of "elongation" while we are working according to ASME Sec. VIII div. 1?

 

[metengr]

ASME SA 213, section 9.2 specifies computed elongation values (based on a decrease in wall thickness - 1/32" decrease) for strip tests used to measure elongation. Please Read Note 2 in Table 5.

If you used strip tests for determining mechanical properties, yes, you can use computed elongation as mentioned in 9.2 and using the thickness of the strip in Table 6.

 

[deanc]

Agree with metengr

Here is a handy guide.

http://www.aalco.co.uk/technical/datasheets/Aalco_Datasheet_Al_Test_Certificates.pdf