Section 56.95-10 - Type and extent of examination required(a)General. The types and extent of nondestructive examinations required for piping must be in accordance with this section and Table 136.4 of ASME B31.1 (incorporated by reference; see § 56.01-2 ). In addition, a visual examination must be made.(1) 100 percent radiography is required for all Class I, I-L, and II-L piping with wall thickness equal to or greater than 10 mm (0.393 in.). Note 1 to paragraph (a)(1):
Throughout this this section, where for some reason, such as joint configuration, radiography is not applicable, another approved examination may be utilized.
(2) Nondestructive examination is required for all Class II piping equal to or greater than 18 inches nominal diameter regardless of wall thickness. Any test method acceptable to the Officer in Charge, Marine Inspection may be used.(3) Nondestructive examinations of other piping systems are required only when deemed necessary by the Officer in Charge, Marine Inspection (OCMI).(b)Visual examination. Visual examination consists of observation by the marine inspector either before, during, or after manufacture, fabrication, assembly, or test. All welds, pipe and piping components must comply with the limitations on imperfections specified in the product specification or with the limitations on imperfections specified in § 56.70-15(b)(7) and (8), and (c) , as applicable.(c)Nondestructive types of examinations - (1)100 Percent radiography. Where 100 percent radiography is required, each weld in the piping must be completely radiographed. If a butt weld is examined by radiography, for either random or 100 percent radiography, the method used must be as follows: (i) X-ray or gamma ray method of radiography may be used. The selection of the method must be dependent upon its adaptability to the work being radiographed. The procedure to be followed must be as indicated in PW-51 of Section I of the ASME BPVC (incorporated by reference; see § 56.01-2 ).(ii) If a piping component or a weld other than a butt weld is radiographed, the method used must be in accordance with UW-51 of Section VIII of the ASME BPVC (incorporated by reference; see § 56.01-2 ). (2)Random radiography. Where random radiography is required, one or more welds may be completely or partially radiographed. Random radiography is desirable in field welding, where conditions such as position, temperatures, and cleanliness are not as controlled as in shop welding. It may be employed whenever an Officer in Charge, Marine Inspection questions a pipe weld not otherwise required to be tested. The standards of acceptance are the same as for 100 percent radiography.(3)Ultrasonic. Where 100 percent ultrasonic testing is specified, the entire surface of the weld being inspected must be covered using careful methods to be sure that a true representation of the actual conditions is obtained. The procedures to be used must be submitted to the Commandant for approval.(4)Liquid penetrant. Where liquid penetrant examination is required, the entire surface of the weld being examined must be covered. The examination must be performed in accordance with appendix VIII to Section VIII of the ASME BPVC. The following standards of acceptance must be met: (i) All linear discontinuities and aligned penetrant indications revealed by the test must be removed. Aligned penetrant indications are those in which the average of the center-to-center distances between any one indication and the two adjacent indications in any straight line is less than three-sixteenths inch. All other discontinuities revealed on the surface need not be removed unless the discontinuities are also revealed by radiography, in which case the pertinent radiographic specification applies.(5)Magnetic particle. Where magnetic particle testing is required, the entire surface of the weld being examined must be covered. The testing must be performed in accordance with Appendix VI to Section VIII of the ASME BPVC. The following standards of acceptance are required for welds. All linear discontinuities and aligned indications revealed by the test must be removed. Aligned indications are those in which the average of the center-to-center distances between any one indication and the two adjacent indications in any straight line is less than three-sixteenths inch. All other revealed discontinuities need not be removed unless the discontinuities are also revealed by radiography, in which case the requirements of paragraph (c)(1) of this section must be met.CGFR 68-82, 33 FR 18843, Dec. 18, 1968, as amended by CGD 72-206R, 38 FR 17229, June 29, 1973; CGD 78-108, 43 FR 46546, Oct. 10, 1978; CGD 77-140, 54 FR 40615, Oct. 2, 1989; CGD 95-028, 62 FR 51202, Sept. 30, 1997; USCG-2000-7790, 65 FR 58460, Sept. 29, 2000; USCG-2003-16630, 65185, Oct. 31, 2008