D1.2 Maximum weave width GTAW 1

[amorton5]

Hey everybody,
Welding a bunch of 1/2" fillet welds on aluminum, using ER4043.
The welders are putting in a root pass, one cover pass and then waving the cap or cover pass to complete.
They are using 3/16" tig wire and up to 1/4" tungsten.

Does anyone know the maximum weave width for AWS D1.2 using the GTAW process on a fillet weld.
The WPS says stringer or weave, I can't find anything in D1.2 2014 that limits weave width. I know the
old rule of thumb width of the cup but can we prove this in code.

 

[gtaw]

Since AWS D1.2 does not include prequalified welding procedures, one must qualify the WPS. Many heat treatable aluminum alloys and some of the nonheat treatable alloys are time at temperature sensitive. In short, one must limit the heat input and interpass temperature to minimize the width of the HAZ and the degradation of the mechanical properties.

If my memory serves me, D1.2 requires the contractor to qualify fillet welds separately from groove welds. The testing regiment for fillet welds isn't all that difficult, but there is a bone in the soup. The code also requires the mechanical properties be verified by welding a grooved joint. If the interpass temperatures are not controlled, the tensile test results will not pass muster.

The production WPS should include restriction on the heat input and interpass temperatures based on the welding parameters used to weld a test plate that produced acceptable results (as recorded in the PQR).

The bottom line is, "What did they do to qualify the WPS?" If the information wasn't recorded, maybe additional testing is in order.

The code specifies the minimum requirements that must be met. The contractor has a responsibility to take any necessary additional steps needed to ensure their product will perform as expected.

In this case, if the alloy is 6061-T6, I can assure you the mechanical properties of the weld are not met if the welders are using high heat input and maintaining high interpass temperatures.

Best regards - Al

 

[DekDee]

As usual Al - very informative response.