API 5CT Welding PROCEDURE

[falco]

Good Morning,

Perhaps someone can be of assistance. I am qualifying a procedure to Butt weld steel which is under the specification API 5CT Grade K55. This is normally used in drilling and we use it in geothermal application for vapor under 300 psi and 180 C.
I´m trying to find an API RP or API STD in which there are specifications about the welding procedure qualification guidelines for that type of steel.
I would understand that it might be beyond the ASME scope unless the API governing document would refer to SEC IX. If anyone knows about a standard or recommended practice I will highly appreciate if you can let me know it
best regards

 

[DekDee]

falco,
Pretty sure you will not find any documentation telling you what code/standard to qualify a specific material to.
The responsible Engineer will nominate a specific code/standard based on the service, pressure, temperature etc and you have to qualify your procedure in accordance with that code/standard.
If the material you want to use is not recognised by that code/standard then it is classed as an "Unassigned or Unlisted" material.
You can still qualify your WPS but in some cases you will be required to perform additional testing than if it was a "recognised" material.
Based on your product, pressure and temperature listed it could possibly fall under B31.1 or B31.3 which then leads you back to ASME IX,
Regards,
DD