S9074-AQ-GIB-010/248 Rev 1
j. In robotic, automatic, or mechanized weld cladding or hardfacing, a change from a simple harmonic to a constant-velocity oscillating motion or vice versa. k. In the plasma arc process, a change in the type or model of welding equipment. l. In plasma arc weld cladding or hardfacing, a change of 10 percent or more in the diameter of the constricting orifice in the torch. m. In robotic, automatic, or mechanized plasma arc weld cladding or hardfacing, a change greater than ±15 percent in the travel speed range recorded in the procedure qualification record. n. In robotic, automatic, or mechanized weld cladding or hardfacing, a change greater than ±20 percent in oscillation displacement recorded in the procedure qualification record. A procedure qualified using a minimum oscillation displacement and a procedure qualified using a maximum oscillation displacement, with all other essential variables remaining the same, shall qualify for all weld bead oscillations in between. o. In robotic, automatic, or mechanized weld cladding or hardfacing with oscillation, a change in dwell time from that used for qualification greater than the following: (1) ±20 percent for cladding. (2) Any change for hardfacing. p. In robotic, automatic, or mechanized weld cladding or hardfacing with oscillation, a change in the frequency of oscillation greater than ±20 percent beyond the frequency used for qualification. q. In robotic, automatic, or mechanized weld cladding or hardfacing, the omission of self-regulating arc length or voltage control if the procedure was qualified with such control. In this regard, a constant potential power supply is considered to be a self-regulating voltage control. r. Where toughness testing is required by table 7-7, footnote 2, an increase in bead width or oscillation as follows (also see 4-8.j): (1) For manual or semi-automatic welding with weaving, an increase in bead width to more than 3/4 inch, or for qualified widths of more than 3/4 inch, a bead width increase greater than 3/8 inch. (2) For mechanized, automatic, and robotic welding with oscillation, an increase in amplitude (see 3-2.11.a) to more than 1/2 inch, or for qualified amplitudes of more than 1/2 inch, an amplitude increase greater than 1/4 inch or 20 percent, whichever is greater. s. For stud welding, a change in the lift greater than ±1/32 inch; also, a change in plunge exceeding ±1/16 inch. t. For stud welding, a change in the model of the power supply or stud gun. u. For stud welding, a change in flux type or load (e.g., a ball load to a ring load and vice versa, or a ball or ring load to a fluxless stud and vice versa). v. A change in shielding from ferrule or flux (see 4-4.4.e). w. For machine settings other than those specifically listed in 4-4.4, see 4-4.4.h. 4-7.5 ELECTRICAL CHARACTERISTICS. a. Except for a shielded metal arc process, a change in the welding current from AC to DC or vice versa, or a change in polarity. b. For base metals having toughness requirements, an increase in the heat input over that qualified (also see 4- 4.1.13, 4-7.5.f, and 4-7.9.1.g). Fabrication document requirements for heat input shall not be exceeded in any case for production welding. c. For socket and fillet seal weld procedures in pipe with nominal wall thickness less than 3/16 inch, a change in welding current greater than 15 percent from that used for qualification. d. In plasma arc weld cladding or hardfacing, a change greater than 10 percent in the welding current or voltage recorded in the procedure qualification record. e. In plasma arc weld surfacing, a change greater than 10 percent in the filler wire wattage recorded in the procedure qualification record. Wattage refers to resistance-heated filler wire and is a function of current voltage and wire stickout dimension.
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