Low alloy steel welding with Carbon steel

[metboss]

Hi all,

We want to weld a Drilling tubular material with Vanes (rectangular shaped blades). Tubular material T-95 grade (API 5CT) of size 13” OD to be welded(fillet weld) with AISI 1040 carbon steel material of size 100 mm length x 15 mm thickness (rectangular bars).
What should be pre-heat and PWHT temperature to keep hardness value (weld metal & HAZ) within the acceptable range of API 5CT (i.e. 26 HRC max). What are the other parameters to be considered while qualifying the WPS?

Thank you in advance for your response.

 

[kingnero]

26 HRC ? That gives you not much leeway. Will require quite a bit of preheat.
I don't know the american codes (very well), do you have impact requirements?
Mind that too much preheat negatively affects the charpies.

 

[weldstan]

PWHT may well be required.