Welded pipe joint efficiency for UG-27 calculation

[jakov11000]

Hello,

I have SA-53E/B (welded pipe) used as a shell.

ASME section II partD gives 14600 psi for max allowable stress at 200F.
In notes it is indicated that this value (14600 psi) includes 0.85 joint efficiency factor.

I read the UW-12 and my understanding is that I can use E=1 in UG27 formula for required shell thickness, provided that 14600 psi (value that includes E=0.85) is used as maximum allowable stress.
Is my understanding correct.

No additional NDE has been performed other than those specified by SA-53.

Many Thanks,
Jakov11000

 

[metengr]

Yes. However, the value of E=1 in UW-12 is based on volumetric examination of the ERW pipe under the requirements in SA 53. If this was not the case, you would either have NDT performed of the seam weld or take a greater weld reduction factor.