xray of welds

[synodc]

I have looked in our company specs and API 1104 but can't find any requirements on wait time before a production weld on pipeline should be x-rayed. Are there any guidelines for this?

 

[metengr]

If the B31 piping codes do not require it, it is by company engineering specification.

 

[SJones]

Minimum time or maximum time? If minimum, then it is customary to have a substantial delay between test weld completion and NDT for acceptance - 24 to 48 hours are frequently specified - when undertaking welding procedure qualification. This then allows production NDT to occur much sooner since the lack of delayed cracking has been 'qualified'. After all, an offshore laybarge isn't going to wait around that long before getting the joint under water!

Welding Journal, Vol 82, (11), 2003, pp. 321s - 329s will give you some background to help formulate your approach.

Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04