Friday, May 13, 2016

No means No

Paul,
Here’s a question. I’m certified through the Iron Workers Union and I been welding for almost 19 years. Everywhere I've ever worked they says no welding downhill and if you weld downhill you won't pass the structural test.  When running a vertical weld with 7018 rod is it correct to run a downhill pass before you start your vertical ups on Structural Steel? (This email was in response to welding per AWS D1.1:2015 Structural Code – Steel)
Joshua R.

Joshua,
I guess the short answer is "No".
To do so, you would need a weld procedure (WPS/PQR) that qualifies welding vertical up & down with E7018.  You might struggle to find an electrode manufacturer that would support vertical down with E7018.  We’re required to use electrodes within the manufacturer’s requirements.
You (the Welder) would also need to have taken a vertical up and a vertical down Welder Qualification test with E7018 (or another Low-Hydrogen electrode).  These would be F4 electrodes.  Welding vertically down is often done with F3 electrodes, but a structural test with an F3 (E6010) will not qualify you to weld with an F4 (E7018).
I always say that the pre-qualified section of AWS-D1.1 (Clause 3 – Prequalified Weld Procedure Requirements) is filled with good engineering advice.  My “day job” consists of Ultrasonic Testing (UT) of steel structures.  Often, when I find rejects, I also find that some requirement of Clause 3 was not met. When asked, “What should we do now?” my response is always the same, “Meet the Clause 3 requirements.”  That’s not often a popular response.
Clause 3, wouldn't allow welding vertically down with E7018, so again, my best answer is still, “No”.

Good Luck,
PWC