Coast Guard, Dept. of Homeland Security § 56.75–30

pounds per square inch or the tempera- (b) [Reserved] ture exceeds 750 °F. or in Class I-L sys- [CGFR 68–82, 33 FR 18843, Dec. 18, 1968, as tems. amended by USCG–2003–16630, 73 FR 65184, [CGFR 68–82, 33 FR 18843, Dec. 18, 1968, as Oct. 31, 2008] amended by USCG–2003–16630, 73 FR 65184, Oct. 31, 2008] § 56.75–20 qualification. (a) The qualification of the perform- Subpart 56.75—Brazing ance of brazers and brazing operators shall be in accordance with the require- § 56.75–5 Filler metal. ments of part C, section IX of the (a) The filler metal used in brazing ASME Boiler and Pressure Vessel Code (incorporated by reference; see 46 CFR must be a nonferrous metal or alloy 56.01–2) and part 57 of this subchapter. having a melting point above 1,000 °F. and below that of the metal being (b) Manufacturers shall perform joined. The filler metal must meet and those tests required by paragraph (a) of this section prior to performing pro- flow freely within the desired tempera- duction brazing. ture range and, in conjunction with a suitable flux or controlled atmosphere, [CGFR 68–82, 33 FR 18843, Dec. 18, 1968, as must wet and adhere to the surfaces to amended by USCG–2003–16630, 73 FR 65184, be joined. Prior to using a particular Oct. 31, 2008] brazing material in a piping system, the requirements of § 56.60–20 of this § 56.75–25 Detail requirements. part should be considered. (a) Pipe may be fabricated by brazing (b) The brazing material used shall when the temperature to which such have a shearing strength of at least connections may be subjected does not 10,000 pounds per square inch. The max- exceed 425 °F. (For exception refer to imum allowable working pressure for § 56.30–30(b)(1).) brazing piping shall be determined by (b) The surfaces to be brazed must be this part. clean and free from grease, oxides, (c) Fluxes that are fluid and chemi- paint, scale, and dirt of any kind. Any cally active at the brazing temperature suitable chemical or mechanical clean- must be used when necessary to pre- ing method may be used to provide a vent oxidation of the filler metal and clean, wettable surface for brazing. of the surfaces to be joined and to pro- (c) After the parts to be joined have mote free flowing of the filler metal. been thoroughly cleaned the edges to be brazed shall be given an even coat- [CGFR 68–82, 33 FR 18843, Dec. 18, 1968, as ing of flux prior to heating the joint as amended by CGD 77–140, 54 FR 40615, Oct. 2, a protection against oxidation. 1989; USCG–2003–16630, 73 FR 65184, Oct. 31, 2008] [CGFR 68–82, 33 FR 18843, Dec. 18, 1968, as amended by USCG–2003–16630, 73 FR 65184, § 56.75–10 Joint clearance. Oct. 31, 2008] (a) The clearance between surfaces to § 56.75–30 Pipe joining details. be joined shall be no larger than is nec- essary to insure complete capillary dis- (a) Silver brazing. (1) Circumferential tribution of the filler metal; between pipe joints may be either of the socket 0.002–inch minimum and 0.006-inch or butt type. When butt joints are em- maximum. ployed the edges to be joined shall be (b) [Reserved] cut or machined square and the edges shall be held closely together to insure [CGFR 68–82, 33 FR 18843, Dec. 18, 1968, as a satisfactory joint. amended by USCG–2003–16630, 73 FR 65184, (b) Copper-alloy brazing. (1) Copper- Oct. 31, 2008] alloy brazing may be employed to join pipe, valves, and fittings. Circumferen- § 56.75–15 Heating tial joints may be either of the butt or (a) The joint shall be brought to braz- socket type. Where butt joints are em- ing temperature in as short a time as ployed, the included angle shall be not possible to minimize oxidation. less than 90° where the wall thickness

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is three-sixteenths of an inch or great- the pipe covering. The nondestructive er. The annular clearance of socket method shall be employed where the joints shall be held to small clearances design temperature exceeds 750 °F. which experience indicates is satisfac- Prior to the use of nondestructive tory for the brazing alloy to be em- method of examination by the above ployed, method of heating, and mate- procedure, it shall be demonstrated by rial to be joined. The annular clearance the user, in the presence of a marine shall be shown on drawings submitted inspector on specimens similar to those for approval of socket joints. to be examined, that consistent re- (2) Copper pipe fabricated with longi- sults, having an accuracy of plus or tudinal joints for pressures not exceed- minus 3 percent, can be obtained. ing that permitted by the regulations in this subchapter may have butt, [CGFR 68–82, 33 FR 18843, Dec. 18, 1968, as amended by CGFR 69–127, 35 FR 9979, June 17, lapped, or scarfed joints. If of the latter 1970; USCG–2003–16630, 73 FR 65185, Oct. 31, type, the kerf of the material shall be 2008] not less than 60°. (c) Brazing, general. (1) Heat shall be § 56.80–10 Forming (reproduces 129.2). applied evenly and uniformly to all (a) Piping components may be parts of the joint in order to prevent formed (, lapping, or upsetting local overheating. of pipe ends, of necks, etc.) (2) The members to be joined shall be by any suitable hot or held firmly in place until the brazing method, providing such processes re- alloy has set so as to prevent any sult in formed surfaces which are uni- strain on the joint until the brazing form and free of cracks or other de- alloy has thoroughly solidified. The fects, as determined by methods of in- brazing shall be done by placing the spection specified in the design. flux and brazing material on one side of the joint and applying heat until the § 56.80–15 Heat treatment of bends and brazing material flows entirely formed components. through the lap and shows uniformly (a) Carbon-steel piping that has been along the seam on the other side of the heated to at least 1,650 °F (898 °C) for joint. Sufficient flux shall be used to bending or other forming requires no cause the brazing material to appear subsequent heat treatment. promptly after reaching the brazing (b) Ferritic alloy steel piping which temperature. has been heated for bending or other forming operations shall receive a Subpart 56.80—Bending and stress relieving treatment, a full an- Forming neal, or a normalize and temper treat- ment, as specified by the design speci- § 56.80–5 Bending. fication before . Pipe may be bent by any hot or cold (c) Cold bending and forming of car- method and to any radius which will bon steel having a wall thickness of result in a bend surface free of cracks, three-fourths of an inch and heavier, as determined by a method of inspec- and all ferritic-alloy pipe in nominal tion specified in the design, and sub- pipe sizes of 4 inches and larger, or one- stantially free of buckles. Such bends half-inch wall thickness or heavier, shall meet the design requirements of will require a stress-relieving treat- 102.4.5 and 104.2.1 of ASME B31.1 (incor- ment. porated by reference; see 46 CFR 56.01– (d) Cold bending of carbon-steel and 2). This shall not prohibit the use of ferritic-alloy steel pipe in sizes and bends designed as creased or cor- wall thicknesses less than specified in rugated. If doubt exists as to the wall 129.3.3 of ASME B31.1 (incorporated by thickness being adequate, Class I pip- reference; see 46 CFR 56.01–2) may be ing having diameters exceeding 4 used without a postheat treatment. inches shall be nondestructively exam- (e) For other materials the heat ined by the use of ultrasonics or other treatment of bends and formed compo- acceptable method. Alternatively, the nents must be such as to ensure pipe pipe may be drilled, gaged, and fitted properties that are consistent with the with a screwed plug extending outside original pipe specification.

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