API-1104 Base material for procedure qualification.

[alkeeprollin]

Hi,

With regards to API-1104 Section-5.4.2.2. Can you please inform if I am interpreting the section on base materials correctly.

1. If i qualify a weld procedure using API X70 to X70 pipe, this will allow me to formulate several weld procedure specifications
for welding X70 pipe material to any base material in group (a) or Group (b).

2. I will not be allowed to formulate a WPS for welding X70 pipe to X65 pipe material from the previosly mentioned X70 to X70 weld procedure because both material are in the same group(c).

3. A procedure qualification for a combination of materials only qualify the procedure for that combination of material.

 

[SJones]

1. Yes - if allowed by the end user

2. Technically and contractually, correct - but, realistically, would there be substantial difference in dropping the SMYS by 30 MPa? The actual properties of the L450 are likely to exceed the specified minima for L480. One for discussion with the end user.

3. Not addressed by API 1104. Most major operators would not allow grouping by strength. The principal base material essential variables tend to be: grade, manufacturing location (even down to steel source), manufacturing process, and chemical composition. If grouping is allowed under your contract, it could be argued that if both sides of the weld received the full range of tests, then the grouping arrangement can apply to both sides within the ranges agreed.

Steve Jones
Materials & Corrosion Engineer

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

All answers are personal opinions only and are in no way connected with any employer.

 

[alkeeprollin]

Hi Steve,

Thanks for sharing your Knowledge.
All questions answered.