341.4.2–341.5.1 ASME B31.3-2004 Table 341.3.2 Acceptance Criteria for Welds and Examination Methods for Evaluating Weld Imperfections (Cont’d) NOTES: (1) Criteria given are for required examination. More stringent criteria may be specified in the engineering design. See also paras. 341.5 and 341.5.3. (2) Longitudinal groove weld includes straight and spiral seam. Criteria are not intended to apply to welds made in accordance with a standard listed in Table A-1 or Table 326.1. Alternative Leak Test requires examination of these welds; see para. 345.9. (3) Fillet weld includes socket and seal welds, and attachment welds for slip-on flanges, branch reinforcement, and supports. (4) Branch connection weld includes pressure containing welds in branches and fabricated laps. (5) These imperfections are evaluated only for welds ≤ 5 mm ( 3 / 16 in.) in nominal thickness. (6) Where two limiting values are separated by “and,” the lesser of the values determines acceptance. Where two sets of values are separated by “or,” the larger value is acceptable. T w is the nominal wall thickness of the thinner of two components joined by a butt weld. (7) Tightly butted unfused root faces are unacceptable. (8) For groove welds, height is the lesser of the measurements made from the surfaces of the adjacent components; both reinforcement and internal protrusion are permitted in a weld. For fillet welds, height is measured from the theoretical throat, Fig. 328.5.2A; internal protrusion does not apply. (9) For welds in aluminum alloy only, internal protrusion shall not exceed the following values: (a) for thickness ≤ 2 mm ( 5 / 64 in.): 1.5 mm ( 1 / 16 in.); (b) for thickness > 2 mm and ≤ 6 mm ( 1 / 4 in.): 2.5 mm ( 3 / 32 in.). For external reinforcement and for greater thicknesses, see the tabulation for Symbol L. 341.3.2, for Category D fluid service, unless otherwise specified. 341.4.3 Examination — Severe Cyclic Conditions. Pip- ing to be used under severe cyclic conditions shall be examined to the extent specified herein or to any greater extent specified in the engineering design. Acceptance criteria are as stated in para. 341.3.2 and in Table 341.3.2, for severe cyclic conditions, unless otherwise specified. (a) Visual Examination. The requirements of para. 341.4.1(a) apply with the following exceptions. (1) All fabrication shall be examined. (2) All threaded, bolted, and other joints shall be examined. (3) All piping erection shall be examined to verify dimensions and alignment. Supports, guides, and points of cold spring shall be checked to ensure that movement of the piping under all conditions of startup, operation, and shutdown will be accommodated without undue binding or unanticipated constraint. (b) Other Examination. All circumferential butt and miter groove welds and all fabricated branch connection welds comparable to those shown in Fig. 328.5.4E shall be examined by 100% radiography in accordance with para. 344.5, or (if specified in the engineering design) by 100% ultrasonic examination in accordance with para. 344.6. Socket welds and branch connection welds which are not radiographed shall be examined by magnetic particle or liquid penetrant methods in accordance with para. 344.3 or 344.4. (c) In-process examination in accordance with para. 344.7, supplemented by appropriate nondestructive examination, may be substituted for the examination 73 required in (b) above on a weld-for-weld basis if speci- fied in the engineering design or specifically authorized by the Inspector. (d) Certification and Records. The requirements of para. 341.4.1(c) apply. 341.5 Supplementary Examination Any of the methods of examination described in para. 344 may be specified by the engineering design to sup- plement the examination required by para. 341.4. The extent of supplementary examination to be performed and any acceptance criteria that differ from those in para. 341.3.2 shall be specified in the engineering design. 341.5.1 Spot Radiography (a) Longitudinal Welds. Spot radiography for longitu- dinal groove welds required to have a weld joint factor E j of 0.90 requires examination by radiography in accor- dance with para. 344.5 of at least 300 mm (1 ft) in each 30 m (100 ft) of weld for each welder or welding operator. Acceptance criteria are those stated in Table 341.3.2 for radiography under Normal Fluid Service. (b) Circumferential Butt Welds and Other Welds. It is recommended that the extent of examination be not less than one shot on one in each 20 welds for each welder or welding operator. Unless otherwise specified, accept- ance criteria are as stated in Table 341.3.2 for radiogra- phy under Normal Fluid Service for the type of joint examined. (c) Progressive Sampling for Examination. The provi- sions of para. 341.3.4 are applicable. (d) Welds to Be Examined. The locations of welds and the points at which they are to be examined by spot