Weld Overlay

[FYS]

Is there any requirements for PWHT due to application of Weld Overlay (CS backing material + Alloy 625-3mm weld overlay) on piping, manifold?

 

[metengr]

What is the code of construction for the piping, manifold?

 

[OGMetEngr]

Also, if NACE MR0175/ISO 15156 is required (sounds like a possibility) what is the hardness testing method for weld qualification? What carbon steel ASTM and chemical composition is the carbon steel?

 

[Guest102023]

Are you expecting to obtain full corrosion-resistant chemistry in just 3mmm thick weld overlay?

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

 

[OGMetEngr]

The requirement for weld dilution %Fe in, for example, API 6A is readily achievable with a 3mm final thickness overlay. The overlay must be done in two passes, then machined down to 3mm.

 

[gr2vessels]

A normal dilution of 7-10% Fe at the surface of 3 mm Alloy 625 will maintain full corrosion resistance PREN above 40 in most of the corrosive hydrocarbon environments;- refer below limits for maximum corrosion resistance:
ISO 21457 - maximum iron content at the finished surface shall be 10 weight percent.
Norsok M001 - maximum iron content at the finished surface shall be 10 weight percent.

 

[weldstan]

Are the welds in the pipe manifold subject to PWHT?