Classification ER70S-6

[1973Patrick]

Hi,
Issue with classification ER70S-6 - SF 5.18 and A No.1 classification.
ASME IX QW-442 says maximum 1.60 Mn and Si 1.0 for A No.1
ASME II C SFA 5:16 says Si 0.80-1.15 and Mn 1.40-1.85 (same as AWS 5.18)
Why these 2 differences and what should I use?
We have a 2.4 mm LNT 26 Lincoln filler material with Si 0.82 and Mn 1.47

Patrick

 

[jwhit]

If you are doing a procedure you will use both. The SFA 5.18 is the material specification. Most ( I did not review 5.18 for this) compositions in 5.18 will meet A No. 1 which is a grouping of similar composition filler metals. When filling out the QW482 or QW483 forms you will have Spec No. SFA5.18, AWS Class ER70S-6, F No.6 and A No. 1. Composition of the filler must meet what is shown in 5.18 ER70S-6. ER70S-2 has a different composition but the class is the only thing that changes. If you had a filler with 1.65 Mn, for example, which was classed as ER70S-G, your A No. would be listed as NONE since it doesn't fall into the A No. 1 range.

 

[metengr]

Also, I have seen many ER70S-6 filler metals meet the ASME A-No 1 classification, while other filler metals were formulated that resulted in not fitting an A-No classification, and as such, the procedure was qualified with as deposited filler metal with no A-No reported or N/A.

 

[weldstan]

In the past 15 years, I have seen no ER70S-6 filler metal heat chemistries that did not meet A-1 analysis. You can specify a 1.6% max Mn content in your WPS and obtain verification chemistry to the A-1 analysis if you so desire. You can also qualify the procedure with ER70S-6 and the PQR is valid for all ER70S-6 purchased filler metals and specify None or N/A for the A No. analysis as per metengr and jwhit.

 

[Duwe6]

further caveat: the "A" really stands for 'Analysis of Weld Puddle'. The alloy content of unused wire is not the official analysis. What you need is the "As-Welded" analysis; the act of welding changes a lot of the bare-wire constituents, especially depletes the deoxidizer elements like Si and Al.

Fillers with flux; SMAW, FCAW, and especially SAW have dramatically different As-Welded chemistries when compared to the bare wire used. The flux supplies most of the alloying elements.