Filler Substitution

[QANo1]

I have a SMAW WPS that is meant to be used for welding with E2553 filler or an allowable substitution, per Code. I want to use E2594, instead, but am not sure if it is permitted because E2553 does not fall into a specific A-number designation and the A-number is an essential variable. The chemistry between the two is very similar. How can I confirm whether or not the E2594 can be used?

 

[david339933]

As you stated, A number is an essential variable, and therefore any change outside of the A number qualified will mandate re-qualification. Are you sure E2553 isn't A-8?

 

[QANo1]

The Ni and Mo for E2553 are outside the ranges for A-8.

 

[david339933]

Then you are limited to the AWS Classification qualified E2553.

 

[QANo1]

Thank you.

 

[DekDee]

QANo1,
Based on ASME IIC the nominal composition of E 2553 is 25 Cr, 7.5 Ni, 3.5 Mo & 2 Cu
A-8 in ASME IX is Ni 7.5 to 15 and Mo is 4 maximum.
Not sure where you have the problem ?

What A No. is listed on the WPS ?
Cheers,
DD

 

[QANo1]

DekDee,

The nominal composition is what is on the WPS. The thing that is questionable to me, and it could just be I need some clarification on this, is that the full allowable range of the E2553 goes outside of the range for A-8.

E2553 = 6.5-8.5 Ni is allowed (IIC), but A-8 only allows for 7.5-15.

You are correct about the Mo. That was a mistake.

So when trying to fit a filler into an A-number, I figured the full range had to be within the A-number range. Is this wrong?

Thanks.

 

[DekDee]

QANo1,
Look at QW 404.5 (a) or (b).
Did you have a chemical analysis done on your PQR coupon ?
If not, what was the chemical composition of your electrodes on the batch certificate (actual - not typical) ?
If the composition of either (or both) fall within the requirements of A 8 that is the A number to be listed on PQR / WPS.
Same goes with E2594 - if the chemical analysis or composition on the certificate falls within the A 8 range then it is an acceptable substitution.

Ranges of filler metals, base metals etc are quite often lesser or greater than the allowable code requirements - the important thing is what you are actually using.
As an example - when you put in a purchase order for your E2553 you request Ni minimum of 7.5% so you stay in compliance with ASME IX A 8 requirements..
As the acceptable range (as per IIC) is 6.5 - 8.5 the manufacturer (or supplier) may have electrodes in stock of 6.5. 7.0, 7.5 & 8% Ni but the 6.5 & 7.0% are not acceptable for you.
Hope that makes sense,
Cheers,
DD

 

[QANo1]

Yes, makes perfect sense. I did read QW404.5 before posting on here, but this helps me understand it more clearly. I appreciate it.