AWWA C228-14 pdf download.Stainless-Steel Pipe Flange Joints for Water Service
4.1.1 Materials. Materials shall comply with the requirements of the Safe Drinking Water Act and other federal regulations for water systems as applicable.
4.1.2 Permeation. Te selection of materials is critical for water ser- vice and distribution piping in locations where there is likelihood the pipe will be exposed to signifcant concentrations of pollutants composed of low molecu- lar weight petroleum products or organic solvents or their vapors. Documented research has shown that pipe materials (such as polyethylene, polyvinyl chloride) and elastomers, such as those used in jointing gaskets and packing glands, are subject to permeation by low molecular weight organic solvents or petroleum prod- ucts. If a water pipe must pass through such a contaminated area or an area subject to contamination, consult with the manufacturer regarding permeation of pipe walls, jointing materials, and so on before selecting materials for use in that area.
4.1.4 Fasteners. At a minimum, stainless-steel bolts and threaded rods shall be in accordance with ASTM A193 and with a minimum tensile strength of 75,000 psi (515 MPa); nuts shall be stainless steel in accordance with ASTM A194. Bolts shall have regular, unfnished square or hexagonal heads, in accordance with ASME B18.2.1, and nuts shall have regular square or hexagonal dimensions, in accordance with ASME B18.2.2. Bolting shall have product marking in accor- dance with applicable ASTM standards.
Minimum bolt lengths shall be the sum of the mating fange maximum thicknesses, the gasket, the depth of the nut and washer(s), plus 1⁄8 in. (3.2 mm) minimum before torquing. If threaded rods (studs) are used, they shall be the same length as the bolts determined previously, plus the depth of the nuts and the washer(s), plus ¼ in. (6.4 mm) minimum before torquing. Treaded fasteners shall be lubricated or coated to prevent galling.
4.1.5 Gaskets. Tis standard is predicated on gaskets of the type, thick- ness, and material shown in Table l for the class of fange, working pressure limit, and diameter listed.AWWA C228-14 pdf download.