How to calculated a fiber elongation for pipe Cold Bending
How to calculated a fiber elongation for pipe Cold Bending
(OP)
Hi
Any one can help me find out how to calculated fiber elongation after bending as per ASME B31.4 para 332.4.2 (a)
Please help.
Thanks
C.P.
Any one can help me find out how to calculated fiber elongation after bending as per ASME B31.4 para 332.4.2 (a)
Please help.
Thanks
C.P.





RE: How to calculated a fiber elongation for pipe Cold Bending
RE: How to calculated a fiber elongation for pipe Cold Bending
So, the fiber elongation limitation can be calculated as follows;
measure a pre-determined distance on the extrados of the bend (before actual bending). After the bending operation, measure this distance and subtract the two and divide by 100 = % fiber elongation. You use the OD surface of the extrados because this is where the maximum fiber elongation will ocurr.
You had better re-read 332.4.2 in ASME B31.3 because for certain materials, the fiber elongation is limited to 50% of the minimum reported elognation for the material. This means that if the material has a 25% tensile elongation on the material test report, you will be limited to 50% of this value (12.5%) for cold working, otherwise you will need to heat treat the material to remove the effects of deformation from cold bending.
RE: How to calculated a fiber elongation for pipe Cold Bending