Thank you for the help Kent!

Thank you Lawrence very helpful. We have done a similiar application of this design in the past (i.e. early 2000's) with a nickel alloy(C-276) before I worked here. We have around 1,000 parts to weld and it will be welded by manual GMAW in a welding rotator(positioner) working with the equipment we have on hand. we are putting the 1/8" gap between the shoulder of the insert and the edge of the tube for pentration and to reduce excessive reinforcment. With the 1/8" insert shoulder and the 1/8" square groove joint design opening (which has been ok'd with the customer to use a square groove verus a V groove as shown) we will still have 1/4" of the insert still inside past the edge of the tube, the insert is made from solid 1" rd so I dont for see us burning through that material with approiate travel speeds and welding parameters.

There are no prequalified WPS for nickel alloys or anything other than low carbon and high strength low alloy steels included in AWS D1.1, Table 3.1.

So, my comment that you would have to qualify the WPS still applies even if it isn't an ASME application.

I would lean toward GTAW on this project because of the thin wall thickness and small diameter.  

As for qualifying the WPS, I would lean toward AWS D1.1 for the method of qualifying the WPS provided the customer accepts the proposal. AWS D1.1 is more explicit with regards to the information that must be recorded on the PQR, NDT, and mechanical testing required to qualify the WPS. AWS D1.1 also provides a rational basis of determining reasonable ranges for the welding parameters based on the data collected while qualifying the WPS.

While there may be some disagreement, I would start the qualification process by qualifying fillet welds, both the largest single pass fillet weld and the smallest multiple pass weld to establish the usable ranges for voltage, amperage, and travel speed. Then verify the mechanical properties can be met and the welds meet soundness requirements by welding a CJP grooved test assembly.

As Lawrence pointed out, AWS D1.1 isn't intended for this type of application based on the base metal family or thickness, but the approach can be applied for many applications. My concern with qualifying the WPS using either AWS B2.1 or ASME Section IX is they do not provide a rational basis of determining the usable range for the welding parameters. AWS D1.1 offers a good approach for one that isn't intimate with welding or developing WPSs that are usable and welder friendly.

The other modification I would recommend is to adopt test thicknesses that are more in line with the thickness you will be welding. For example, use 1/8 inch thick samples for the single pass fillet weld, 1/4 inch thick samples for the multiple pass fillet weld, and 1/8 inch for the grooved test assembly. 

Best regards - Al

You can Idaho engineer that feeder to push wire into a tig puddle, but you may get a lot of wire whipping around as it comes out of the tip, as you don't have anyplace to put a straightener.  The power supply should work fine, and you can run a water cooled machine torch.  You should be able to rig that hf box to give you a hf start.  Gonna want a torch holder capable of some adjustment if possible. Lotty of Jerry rigging, but it MIGHT work.  Positioner will take some fooling with as you probably want a delay to establish the puddle before it starts to turn.  Watch out for wire sticking in the puddle when you terminate the weld