joining methods

[roky2]

dear sir,
I wants to know what are the suitable welding methods for API 5L grade B pipe?
Thank you.

 

[rneill]

For the longitudinal welds made during pipe manufacturer or for the circumferential butt welds completed during installation ?

 

[roky2]

Circumferential butt welding

 

[roky2]

Dear reneill,
I wants to know for the circumferential butt during instalation,pls advise me what are the suited methods to weld API 5L B Grade pipes.
Thanks

 

[rneill]

Generally, in the work I'm involved with the following are done:

- Shielded Metal Arc (SMAW) for all field welding
- Gas Metal Arc Welding (GMAW) and Tungsten Inert Gas Welding (GTAW) for the root pass of welding done in shops.
- We don't normally permit Flux Cored Arc Welding (FCAW) for piping welds.
- We don't normally permit the use of short circuit GMAW if the piping will be in sour service unless the root pass is back gouged and back welded (usually not possible with the sizes of piping we deal with).

You might want to consult API 1104 "Welding of PIpelines and Related Facilities" and in sour service NACE SP0472 "Methods and Controls to Prevent In Service Environmental Cracking of Carbon Steel Weldments in Corrosive Petroleum Refining Environments".