AWS D1.1 and ASME Sect IX PQRs combinations

Date 06-25-2014 23:01

Dear Experts

Dear Sirs

Pls advise .

AWS D1.1-Structural Welding Code-Steel
ASME IX - ASME Boiler & Pressure Vessel Code

Current situation- Module Tubular Columns( 800mm in dia x 30mm thk ) at assembly stage ( Vertical Position -Butt weld in 2G position ).
Material - AWS Group II- ASTM A131-Grade EH36
Internal accessibility - Not allowed for safety reasons.
So Project suggest to use- Root Run using GTAW and Fill/Cap by FCAW

I want to prepare WPS combining -
1- PQR qualified in 6G position using GTAW in accordance with ASME IX ( Base Material- APL 5L X65 ( CVN at -46 deg C)
2- PQR qualified in 2G position using FCAW( with ceramic Backing Strip ) in accordance with AWS D1.1.( Base Material - AWS Group II-EH36-CVN at -40 deg C)

Can i do it? Does the codes prohibit such combinations? Is there any code Interpretations on this subject?

By 803056

Date 06-26-2014 14:43

The short answer is that ASME Section IX cannot be used as a basis of qualifying a WPS that meets AWS D1.1 welding code for the following reasons:

1) visual acceptance criteria of Section IX does not meet the requirements of AWS D1.1 clause 4.9
2) volumetric examination of the test coupon is not required by Section IX, thus it does not meet AWS D1.1 clause 4 for the required regiment of tests.
3) the acceptance criteria of Section IX does not meet the requirements of AWS D1.1 for guided bend tests.
4) the dimensions of the reduced section tensile test specimens are smaller than that required for AWS D1.1 for plate tests. I do not recollect the dimensions for samples removed from a tubular. You can check those dimensions yourself if you have a copy of D1.1.
5) the essential variables for Section IX are not as inclusive as those of AWS D1.1. Check the tables in AWS D1.1 and compare them to the tables in Section IX. There are glaring differences between the two standards.

Other than that, you're good to go if the Engineer allows you to proceed with your plan of attack.

Best regards - Al

By fschweighardt (***)

Date 06-27-2014 03:00 Edited 06-27-2014 03:03

Use FCAW with backing for the root and fill and cap. What were you going to use the ceramic for if you already had a GTAW root. While you are at it, what is the code of construction? You reference D1.1, and also ASME IX, (which is not a construction code). Are you prohibited from using steel backing?