Welder Qualification ASME with T Shape test coupon 1

[kangomath]

Dear Experts,

This is my very first thread/question ever on this very useful website.
I would like to ask something about how to qualify a welder.
Is it possible to qualify a welder for all position if the welder is tested with a single V-groove test coupon which having Tee-shape like a T weld join on tank shell but slanted 80 degree?
Since on Figure QW-461.1 for overhead and vertical position having same inclination degree on 80 degree from horizontal axis, meanwhile the welder can making a weld on this angle in every angle (0-360) of rotation face for Vertical Position which is in my opinion having the same position with Overhead Position?
Thank you

 

[david339933]

I suggest you check out QW-120, as well as the figures and angles associated with it. This is not where you want to cheap out and try to cut corners. In this industry we talk a lot about good engineering practice. This is not GEP.

 

[david339933]

Link

 

[weldstan]

Why make it difficult? Qualify welders in the 6G position.

 

[kangomath]

Thank you for all replies.
I know 6G will qualify for all position. But I curious why ASME take 80 degree as a limit for a position of 3G, but also at 4G...is that mean if a weld bead position exactly 80,4G or 3G welder can also make a weld on that position without any additional qualification?

 

[gtaw]

Pay close attention the angle of inclination versus the angle of rotation.

In the case of a groove weld, 0 rotation is when the weld face is on the "bottom side" parallel to earth. So, if the rotation of the weld face of the groove weld is any value between 0 to 80 or 280 to 360 degrees we call the position overhead. The position is still overhead if the inclination is 0 to 80 degrees.

It is helpful if one folds a piece of paper to form a "V" and consider the surface of the paper as being the groove face of the weld. With the "V" open toward the ground and the length of the paper level, the position is overhead. As you hold the paper with the open portion of the "V" toward the ground, one can lift one end so the inclination is increased to 80 degrees as long as the paper isn't rotated to the left or to the right. However, it is still the overhead position if the inclination of 0 to 80 degrees and one rotates the paper away from yourself form 0 through 80 degrees or if one rotates the paper toward yourself from 360 through 280 degrees.

You can perform the same exercise with the same folded paper if the paper surface are considered to be the fusion face of the fillet weld, the open portion of the fold considered the face of the fillet weld.

The exercise makes it easier to visualize the positions.

The diagrams in ASME Section IX or AWS D1.1 are the same and are used to determine the required test positions when qualifying the WPS or the welder. It doesn't mean that one can qualify the WPS or the welder with the test coupons inclined or rotated. The coupons must be tested in one of the test positions depicted by the appropriate governing standard. The exception is when testing a tubular in the 6G position. ASME and AWS both allow for a +/- 5-degree tolerance.

I hope this helps.

Best regards - Al