Is 82Ar-18CO2 (Blueshield7) prequalified?

Date 10-03-2007 21:49

I don't see any requirements in Section 3 regarding shielding gases other than the flow rate. Since Section 3 does not address shielding gases, I would say there are no prequalified limitations or requirements on shielding gases.

Now, there are several subsections under Section 5.3 that have limitations or requirements on shielding gases, but those requirements would apply to welding procedures regardless if they are prequalified or qualified through testing.

By shaun420 (*)

Date 10-03-2007 22:01

Thanks for the quick response. I just noticed theres a provision stating that electrode and shielding gas combinations have to be covered in AWS A5.18 or A5.28. Can someone with a copy of that check for me? I don't have a copy of either...

By pax23

Date 10-03-2007 22:19

ER70S-6 is classified within A5.18.

Within A5.18 I find the following, CO2 is the standard shielding gas required by A5.18 for tensile tests performed by the filler metal manufacturer's in order for them to classify their products to E70S-6. However, see note c below which is tagged to the CO2 in the table.

"c. CO2 = carbon dioxide shielding gas (AWS A5.32 Class SG-C). The use of CO2 for classification purposes shall not be construed to preclude the use of Ar/CO2 (AWS A5.32 Class SG-AC-Y) or Ar/O2 (AWS A5.32 Class SG-AO-X) shielding gas mixtures. A filler metal tested with gas blends, such as Ar/O2, or Ar/CO2, may result in weld metal having higher strength and lower elongation. Testing with 100% argon shielding (AWS A5.32 Class SG-A) is required when classification testing is based on GTAW only (see A4.2 in Annex A)."

A5.18 also states the following in its annex:
"A7.4 ER70S-6 [ER48S-6]. Electrodes and rods of the ER70S-6 [ER48S-6] classification are intended for both single- and multiple-pass welding. They are especially suited for sheet metal applications, where smooth weld beads are desired, and structural and plate steels that
have moderate amounts of rust or mill scale. These electrodes permit the use of higher current ranges with either CO2 (AWS A5.32 Class SG-C) shielding gas or with mixtures of argon and oxygen (AWS A5.32 Class SGAO-X) or argon and carbon dioxide (AWS A5.32 Class
SG-AC-Y). However, these electrodes do require a higher level of oxidation than the previously described electrodes when using either binary or ternary argon shielding gas mixtures per the AWS A5.32 specification. Typical base metal specifications are often the same as those for the ER70S-2 [ER48S-2] classification."

The D1.1 code also requires all shielding gases to conform to A5.32 which I expect Blueshield 7 does but you need to verify.

By Lawrence (*****)

Date 10-03-2007 22:31

Shaun

The answer will be yes... The combination is common enough.

The person who is selling you the gas needs to be the one who does the footwork to verify.

Make the clown earn his pay.

Blueshield 7.......... Like it's some exotic mixture.

sheesh

By shaun420 (*)

Date 10-03-2007 22:37

Haha...thanks for the info!