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Factory-Made Wrought Belled End Pipe Fittings for Socket-Welding

GENERAL-This Standard Practice covers the design and manufacturing requirements for factory-made wrought belled end pipe fittings for socket-welding formed from either tubular sections or flat material. Included are the overall dimensions, tolerances, materials, socket end details, heat treatment, marking and other requirements for belled end fittings in sizes NPS 1/2 through 12. The requirements for these belled end fittings are stipulated into each of two pressure service classes: (1) Class MP for stainless steel fittings for use with ASTM A312 pipe; for titanium fittings for use with ASTM B861 or B862 pipe; and aluminum fittings for use with ASTM B241 pipe; and (2) Class MARINE for copper nickel fittings for use with Military Specification MIL-T-16240 pipe or ASTM B466 or B467 pipe.
PARTIAL COMPLIANCE FITTINGS-This Standard Practice may be used to specify Partial Compliance (PC) fittings by agreement between the manufacturer and purchaser. Special considerations include, but are not limited to: dimensions; such as unlisted reducing tee outlet size combinations, or end shapes; such as a street end tee, or custom tolerances. When such fittings meet all other stipulations of this Standard Practice, they shall be considered as being in Partial Compliance herewith, provided they are appropriately marked.
FITTING SHAPES AND TYPES NOT COVERED-This Standard Practice does not cover the design or construction of laterals, wyes, mitered elbows, tees of notch and point or saddle weld types, sweep elbows, sweep tees or any other fitting not described herein by sketch and table.
SERVICE CONDITIONS-This Standard Practice does not cover the criteria for selection of fitting type or fitting materials suitable for a particular fluid type or service.
INSTALLATION WELDING-This Standard Practice does not cover installation-welding requirements. Installation welding shall be done in accordance with the applicable piping system into which the fittings are installed. Pipe joint weld geometry suggestions contained in Section 13 reflect the proportions used in the fatigue tests conducted on pipe pieces used to qualify these fittings for Navy service.


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October 16, 2021

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