S9074-AQ-GIB-010/248 Rev 1
4-7.3 JOINT DESIGN. 4-7.3.1 Full Penetration Joints Welded from One Side Only. For these joints, the following shall apply: a. The omission of a backing ring or backing strip. For dissimilar metal weld joints, the addition of metallic backing or a change in metallic backing S-group (permanent or temporary), except as permitted by 4- 4.1.3.1.1. b. The addition or omission of a consumable insert, except that welding a full penetration joint with or without a consumable insert also qualifies for welding joints with a backing ring or backing strip. c. A change in the shape of a consumable insert. d. A change from a metal backing strip to a ceramic or other non-metallic backing strip. Full penetration joints welded from one side only with or without a backing ring, backing strip, or consumable insert also qualify for welding full penetration joints welded from both sides and partial penetration joints. e. A change from multipass welding to single-pass welding, except as allowed by 4-4.1.7.1. 4-7.3.2 Tube-to-Header Seal Weld Joints for Boiler Components. For these joints, the following shall apply: a. A 1/32-inch or greater decrease in root opening from that qualified. (Root opening is one-half the difference between nominal tube OD and nominal counterbore size.) b. A decrease in included angle of 5 degrees or more from that qualified (any beveling of the header side of the counterbore shall also be considered as part of the weld joint included angle). However, requalification is not required for joints with angular decreases of up to 10 degrees, provided the root opening is at least 1/16 inch greater than that qualified. c. For tube end lands 1/16 inch and smaller, a decrease in tube end land below that qualified. d. An increase in counterbore depth of 1/32 inch or greater beyond that qualified, except that qualification performed on 3/16-inch deep counterbores shall qualify up to and including 1/4-inch deep counterbores. 4-7.3.3 Butt and Fillet Joints in Robotic Welding. For robotic welding, a change from a butt (or other groove) joint to a fillet joint. 4-7.4 PROCESS. a. A change from one welding process to another process (shielded metal arc, gas metal arc, oxyacetylene, gas tungsten arc, flux-cored arc, etc.). b. For gas tungsten arc processes and plasma arc processes, the addition or omission of filler material or a change from electrically hot to cold-wire or vice versa. The addition of filler material at the end of the pass to fill craters is not cause for requalification. c. A change within a process of arc-metal transfer characteristics. For instance, in gas metal arc welding, a change from one mode to any other mode (e.g., spray transfer to globular transfer or vice versa, globular transfer to short-circuiting arc transfer or vice versa). A change to or from the pulsed arc mode in gas tungsten arc welding. d. A change from mechanized, automatic, or robotic to semi-automatic (also see 4-8.aa). e. A change from robotic, automatic, mechanized, or semi-automatic to manual and vice versa. f. A change from single-arc to multiple-arc, or vice versa, or a change to another type of multiple-arc (e.g., from series- to parallel-arc). g. In the plasma arc process, a change in the arc from transferred to non-transferred or vice versa. h. In the robotic, automatic, or mechanized plasma arc process, the addition or elimination of an oscillating motion of the torch or filler wire. i. In robotic, automatic, or mechanized weld cladding or hardfacing with oscillation, the addition or deletion of a dwell period in the oscillation.
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