E7010-P1 equal to E7010-G ? ?

By GDS in KSA Date 06-30-2002 08:03

Quite a bit of pipeline welding is done using E7010-G for the root and possibly hot pass. Our contractors would now like to use AWS A5.5 E7010-P1 electrode, which is becoming more popular lately than E7010-G. My company places certain restrictions on the use of the “G” electrode (mainly, the use of E7010-G is limited to the electrode brand used in the PQR) due to the wide-open nature of the E7010-G designation. Many electrode manufacturers have demonstrated that their company specifications for E7010-P1 currently meet or exceed the same requirements as their E7010-G electrodes satisfied in the past. Does the current experience elsewhere in the world suggest that a new WPS qualification is still required if using E7010-P1 in place of E7010-G, or do other oil and gas companies recognize the E7010-P1 electrode as a refinement of E7010-G? In other words, do you recognize E7010-P1 as equivalent to, or better than, E7010-G without the need for requalification? It looks as if using E7010-P1 in place of E7010-G on a WPS qualified with the “G” electrode does not pose a problem. Your response and suggestions would be greatly appreciated before we make a final decision.

By DGXL

Date 06-30-2002 18:28

GDS,
If you are performing the work for ARAMCO, they have (at least when I was with them 8 years ago) the option of of requiring the exact specification/classification of electrode that was used to qualify the PQR. Some projects also required the same electrode manufacture used during the procedure qualification, it depended on the proponents engineer. Note: This is becoming very common here in the U.S. for many structural applications as well.

I think the rational here may be based upon the as-welded metal deposit.

> The P1 has a slightly higher yield strength requirement (60 ksi vs 57 ksi) than the G classification.
> The P1 does not require PWHT to achieve it's optimum mechanical properties, aging accomplishes this.
> The G classification may require PWHT if the proponent requires.
> The P1 has a CVN requirement of 20 ft-lbs @ 0 degrees F. CVN testing is not required for the G classification.

I also don't think I would compare the E7010G as being "better" then the E7010-P1 due the fact that the P1 has more stringent mechanical property requirements. I would approach this issue as "Does the E7010G electrode meet the requirements of an E7010-P1 electrode?" My answer would be "no".

Get your hands on the current AWS A5.5 specification, this may help. Let the Forum know how you resolve this issue please.

And watch out for the camels. Where theres a camel, theres sure to be camel spiders...

By GDS in KSA Date 07-02-2002 10:52

DGXL,
Thanks for the reply. Your assessment is correct and the ARAMCO restrictions to E7010-G still apply. We compared requirements in AWS A5.5 and feel, at this point, that E7010-P1 is equal to or better than E7010-G but not vice versa. We also feel that using E7010-P1, instead of E7010-G, while using a WPS that was qualified using an E7010-G would not require requalification, but we would like to hear from more of the welding community. Why force many contractors to requalify when Lincoln and Hobart have demonstrated that their E7010-P1 is the same as E7010-G? We have compaired several such WPSs and there is no noticable difference in the results.

By stringer_2000 (*)

Date 07-02-2002 14:32

Please don't take this the wrong way, but just out of curiousity, how did you compare the WPS's? What type of results are you talking about?

By stringer_2000 (*)

Date 08-25-2002 08:29

How did you make out with the E-7010 P1 electrodes?