S9074-AQ-GIB-010/248 Rev 1
b. As an alternate to the tensile tests, studs may be tested by bending as follows: (1) For other than aluminum alloy and titanium alloy studs, hammer each stud over until at least one-fourth of its length touches the test plate, or until the stud is bent more than 90 degrees and the entire inner surface of the stud is within one diameter of the test plate, or until the stud itself fails. The bending of difficult studs may be assisted with a device similar to that shown in figure 7-10. The welds shall exhibit no cracks. In the case of collared studs, remove a portion of the collar to permit hammering of the stud. (2) For aluminum alloy (5000 series) studs, each stud shall be bent to an angle of 15 degrees. For titanium alloy studs, bend testing is applicable only to the ¼-inch stud, which shall be bent to an angle of 10 degrees. There shall be no visible evidence of cracking in the weld zone or shank. The device used for bending may be similar to that shown in figure 7-10. c. Section each stud-weld junction through the diameter along the long axis of the stud; for horizontal position studs, the cut shall be vertical (i.e., 12 to 6 o’clock). Polish, etch, and examine the weld and HAZ under 5× to 10× magnification. Linear indications 1/16 inch and greater in length shall be cause for rejection. d. All stud welds shall be subjected to visual examination. Visible gouging of the stud or base material or visible separation between the stud and base material shall be cause for rejection. For titanium, the weld and the backside of the qualification plate opposite where the studs are welded shall meet the criteria of 4-5.1.1.1. e. For stud welding to base material thicknesses less than d/2 for aluminum or less than d/3 for all other materials, the backside of the qualification plate opposite where the studs are shot shall be free of burn-through, and rejectable melt-through and oxidation as specified in MIL-STD-2035. 4-4.4.2 Procedure Requirements. The stud welding procedure shall contain, at a minimum, the requirements listed in 4-4.4, excluding 4-4.4.j. For S-51, S-52, S-53, and S-53A materials, procedures shall also include: a. Details of the stud and base material contact area preparation and cleaning. b. Statement of workmanship standards, including welding environment, material storage, and handling. 4-4.4.3 Internally Threaded Studs. Internally threaded studs shall be qualified in accordance with 4-4.4.1, provided the stud is long enough to be subjected to bending. If the stud is too short to facilitate bending, the internally threaded stud shall be qualified by subjecting either an unthreaded stud of sufficient length or externally threaded stud that is of the same stud base diameter, end configuration, and material to the requirements of 4-4.4.1. The qualified diameter of the internally threaded stud is the actual stud base diameter, not the internal thread size. 4-4.5 WELDS MADE WITHOUT ADDING FILLER METAL. The test assembly shall consist of a duplicate of the production welds. Each test assembly shall be fully tested in accordance with 4-5. Where test assembly size or shape does not permit the above, testing two macro sections may be substituted for the destructive tests. Unless otherwise approved, the thickness qualified shall be limited to the test assembly thickness ±10 percent. 4-4.6 SEAL WELDS, PIPE SOCKET WELDS AND TUBE-TO-TUBESHEET WELDS (EXCEPT FOR TUBE-TO-HEADER SEAL WELDS; SEE 4-4.8). 4-4.6.1 Socket Joints. For all socket welds, the following shall apply: a. If the base material/filler material combination involved is not covered by Appendix B, a butt weld qualification in accordance with Chapter 4 is required. This butt weld qualification shall be in addition to the tests required for 4-4.6.1. b. For automatic, mechanized, and robotic welding of socket joints, two pipes shall be prepared in accordance with 4-4.1.10 and inspected in accordance with 4-4.6.1.1.1 for each position to be qualified. c. In vertical pipe axis position socket welds, the fitting shall be on top of the pipe (i.e., 4F). d. Qualified thickness shall be per table 7-6. e. Base and filler material groupings of tables 7-1 and 7-2 and the cross-qualification rules of table 7-3 shall apply, except for non-ferrous welds in pipe wall thicknesses less than 3/16 inch, where table 7-3 shall not apply, except for S-34 and S-42 materials welded to themselves or each other.
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