ASME Sec IX (Hard Facing Overlay) 1

[GemmellG]

Developing weld procedure for the Hard Facing Overlay of P4 SA387-Gr.11 1\2" to 1" thick using Stellite 21 (SMAW) This is out of my area of expertise (Boiler Guy). Any impute would be very much appreciated. Client would like to see 0.100" min hard face surface after machining. Also client metallurgist has suggested to apply a butter layer of E309 before applying the stellite 21.

 

[metengr]

GemmellG;
You follow the requirements for ASME section IX WPS qualification for hard facing overlay (HFO). I would suggest a preheat of 350 deg F minimum, and my choice for the butter layer would be Inconel 82 versus 309, for the reason that if the service temperature exceeds 800 deg F, the Gr 11 metal weld region can exhibit carbide migration against the 309 butter.

 

[GemmellG]

Metengr thanks.

 

[MrGezus]

I assume to get the 0.100" minimum overlay, you would have to do one layer? All of my overlay procedures (ASME IX / API 6&16A) have been 0.125" finished machined thickness after weld. How do you accomplish the 0.100?