EXTREME FIBER ELONGATION 1

[kandula1]

Hi,
Can anyone explain me regarding extreme fiber elongation, and its control using Normalizing or PWHT?

 

[metengr]

kandula1;
Extreme fiber elongation is a calculated value based on the type of forming operation for material. If for example you are cold forming (bending) pipe bends, the extreme fiber elongation would be the amount of tensile strain that is calculated on the outer surface or extrados of the bend after forming. The amount of stretch or elongation in the steel surface is compared to a value in the ASME B&PV Code book to determine if thermal treatment is required post bending.

During cold forming, the material properties will change in the region where maximum elongation occurs. When this happens, the material locally strengthens but also suffers from a loss in ductility. Loss of ductility could result in service related cracking. To undo this phenomenon, the material can be thermally treated to restore original strength and ductility.

 

[kandula1]

THANKS FOR CLARIFICATION

 

[fedeghi]

How would you specify a hot forming of an helliptical head (let's to request the supply a dia=1000 thk=22 head).
Is there a norm to be recalled, in order to be sure that the heat treatment is applicable and coherent with my application?

Thanks!

 

[metengr]

Please start a new thread.