Fiber elongation after pipe bending 1

[iwikr]

Dear sir.

Postbending heat treatment is required when the maximum calculated fiber elongation after bending exceeds 50% of the specified basic min. elongation for the applicable material according to para. 332.4.2 of ASME B31.3.

Please let me know how to calculate fiber elongation(equataion)after bedning of the pipe or tube.

 

[BigInch]

Bending the pipe such that the inside radius of the bend remains the same length and all the elongation is at the outside radius of the bend (zero crimping);

L1 = calculate the length of the arc of the pipe after bending [Θ]º using the Bend Radius + (pipe outside diameter / 2).

L2 = calculate the length of the arc of the pipe after bending [Θ]º using the Bend Radius - (pipe outside diameter / 2).

Elongation = L2-L1
Strain = Elongation / L

where;

[Θ]= bend angle

L = original length of straight pipe

BigInch-born in the trenches.

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