Is bend test of welded overlay req'd by ASME?

[Goahead]

Hi,

A carbon steel pressure vessel to be manufactured per
ASME Section IX requirements needs overlay of Cu/Ni 70/30.
The vessel case is manufactured and then the overlay
is applied. The overlay layer is not stressed by manufacturing procedures, beyond welding shrinkage stresses. It is stress relieved after overlay.

Test specimens with overlay fail upon bending.
Is bend testing for welded overlay really required per ASME Sect. IX?
Thanks.

http://www.welding-advisers.com/

 

[ijzer]

Yes , see QW-453

 

[weldtek]

I assume you're referring to bend tests of the procedure test plate failing? Can you tell us the base metal type & thickness, process, & nature of the failure?

 

[metengr]

Yes, ijzer is correct, see note 5 in QW-453 for procedure qualification of a corrosion resistant weld overlay. Sounds to me that you might need to apply a butter layer of high nickel weld followed by depositing the Cu/Ni weld cladding.

 

[Goahead]

August 12, 2005
Thank you all.
Base metal - 3/8" thick SA-516-70
Buffer material 2 layers of ERNiCu-7
Processes: SMAW and SAW
The side bend tests fail because the open discontinuities are greater than 1/16".
SAW - the cracks are in the ERCuNi layers.
SMAW - the cracks are close to the interface of ENiCu-7 and ECuNi
Any hints? Thanks,

http://www.welding-advisers.com/

 

[metengr]

Yes, I would maintain an interpass temperature of only 150 deg C after you deposit your final pass of the butter (or as you say buffer) layer of ERNICu-7, and while depositing the ECuNi filler metal.

 

[Goahead]

Thank you metengr.
Temperature is taken care of.
We will try now to limit iron dilution, in case it is the reason for bend test failures.
Thanks again.

http://www.welding-advisers.com/

 

[weldtek]

If you're using consumables from Special Metals, I'd suggest you talk to Sam Kiser. Let me know if you need his #.

 

[Goahead]

Thank you weldtek for your kind tip.
I started corresponding with Sam and got a nice answer.
The problem is still under investigation but I hope the solution will be found.
Best regards,

http://www.welding-advisers.com/