S9074-AQ-GIB-010/248 Rev 1
4-8 PROCEDURE CHANGES REQUIRING LEVEL II REQUALIFICATION.
One additional qualification test assembly, as specified in 4-2.7.3, shall be welded whenever the following changes are made to a procedure qualified under level I: a. An increase in wire or rod diameter greater than 0.015 inch (0.020 inch for flat position) for gas metal arc and flux-cored arc, or greater than 1/32 inch for gas tungsten arc and plasma arc, than that previously qualified. b. An increase in covered electrode diameter greater than 1/32 inch for horizontal, vertical, and overhead welding and an increase in diameter greater than 1/16 inch for flat position welding or horizontal fillets. c. In robotic, automatic, mechanized, or semi-automatic welding, a decrease greater than 20 percent in the included angle of the welding groove beyond that qualified. d. A change in particle size of flux used in robotic, automatic, mechanized, or semi-automatic submerged arc welding.
e. In tube-to-tubesheet welds, a decrease in the number of weld passes. f. In oxy-fuel gas welding, a change in the type of fuel gas employed.
g. A change greater than ±25 percent in the welding current or voltage from the range qualified for robotic, automatic, mechanized, or semi-automatic welding. Any change in amperage or voltage shall not result in a change in arc metal transfer characteristics unless the procedure is requalified per 4-7.4.c. h. For cladding and hardfacing, a change from vertical-up to vertical-down (see 4-7.9.1.j for vice versa). For other welding, for materials not having toughness requirements, a change in weld progression from vertical-up to vertical-down or vice versa, except for root pass welds that are completely removed by back- gouging; see 4-7.6 for toughness applications. i. In robotic, automatic, or mechanized plasma arc welding, a change of more than 15 percent in the travel speed range recorded in the procedure qualification record. j. Where toughness testing is not required by table 7-7, footnote 2, for robotic, automatic, or mechanized welding with oscillation, a change in the amplitude (see 3-2.11.a), dwell, or frequency of oscillation greater than ±20 percent from that used for qualification (also see 4-7.4.r). Requalification is not required for oscillation parameter changes when oscillation amplitude remains smaller than the nominal electrode diameter. Qualification with minimum and maximum oscillation amplitude, with all other essential variables remaining the same, shall qualify for all amplitudes in between. k. In robotic, automatic, or mechanized welding by circumferential deposition, a change in the torch offset greater than a distance that moves the torch ±5 degrees of the circumference beyond the offset used during qualification. l. In robotic, automatic, or mechanized welding, the omission of self-regulating arc length or voltage control if the procedure was qualified with such control. m. For the plasma arc welding process, termination of a weld made with the keyhole technique after overlapping a completed part of the weld, as occurs in circumferential welds or in repair welding. n. For tube-to-header seal welding, a change greater than ±10 percent in the actual amperage recorded during qualification. o. For the robotic, automatic, or mechanized gas tungsten arc or plasma arc process, a change in filler metal feed rate greater than ±10 percent for powder metal and electrically hot wire or ±20 percent for cold wire from the feed rate used for qualification, except that for changes requiring level I requalification for weld cladding and hardfacing, see 4-7.2.m. p. For cladding and hardfacing, and all welding of S-44, the following changes shall also apply: (1) In robotic, automatic, or mechanized welding employing pulsed current, a change in the pulse frequency greater than ±25 percent or 2 hertz, whichever is greater, or a change in pulse duty cycle (pulse duration as a percent of total cycle time) greater than ±10 percent. (2) In robotic, automatic, or mechanized welding, a change in the tilt or lead angles greater than ±5 degrees beyond the angles used for qualification.
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