ASTM A312 welded pipe

[sw007]

I have one question about welded 304 Stainless Steel pipe.

The applicable pipe specification is ASTM A312. The manufacturer's welding procedures indicate that the pipe is welded by PAW without filler metal (first layer, Machine type) and GTAW (Second layer, Manual type) without filler metal.

My questions:

(1) According to ASTM A312, welded pipe shall be made using an automatic process with no addition of filler metal. Can we use Manual GTAW for the this welded 304SS pipe?

(2) Suppose Manual GTAW is used, can we weld a 12mm thick pipe without filler metal using GTAW Process?

Thanks.

 

[SJones]

1) If the manufacturer uses manual GTAW how will the pipe be certified as meeting the requirements of ASTM A312?

2) What does the manufacturer's PQR say they can weld?

Steve Jones
Materials & Corrosion Engineer

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

 

[sw007]

SJones:

The PQR tests were passed.

 

[SJones]

Then your question 2 has already been answered assuming that the PQR testing was appropriate for the service environment.

Steve Jones
Materials & Corrosion Engineer

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