Weldable Primer WPS 1

[OSUWE2010]

If we are wanting to put a lite coat of weldable primer on the steel to prevent weathering, do we have to qualify a new WPS in order for this to be legal with AWS D1.1? The code seems to be fairly vague when it comes to this and does not say specifically no primer or how much is allowed, at least from what I can find.

 

[metengr]

No, a new WPS does not need to be qualified.

 

[OSUWE2010]

My main issue is that I can't find where it says you either have to qualify a new procedure or not. One way or another, I'd like to know where it say this.

 

[OSUWE2010]

Or, do I have to qualify the welder to be able to weld thru this weldable primer?

 

[metengr]

No, the company I worked for used primer coat on boiler tube ends, structural steel weld prep ends and no separate procedure qualification or welder performance was required.

 

[weldstan]

Approximately 40 years ago we impact test qualified procedures at -50F over three of the primers in use at the time. All of the welds on the aluminum type primers passed.

 

[Duwe6]

And when I was doing nuke work - Sect III - a new PQR/WPS was required. With a max DFT - dry film thickness of one mil, no welder requal was deemed necessary for SMAW 'stick' welding.

 

[DekDee]

You may not need a WPS but you should at least perform "in house" tests before you go ahead and cover everything.
We had a contractor in Malaysia request the use of it and I requested some basic tests be performed first.
Ran a few SMAW welds over a commercially available "weldable primer" and had internal porosity everywhere (nothing on surface).
Ran more tests and it was determined that maintaining a constant DFT was too hard to control - correct application and the welds were fine, overly thick DFT and the welds were hopeless.
Hope that helps,
Cheers,
DD

 

[weldstan]

What DekDee said is so true. When left on their own, the individuals applying the coating often believe that if the coating is perceived as too thin, applying more won't hurt and in fact will be beneficial.