Warning: preg_match_all(): Compilation failed: missing closing parenthesis at offset 76 in /www/wwwroot/standards.biao-zhun.cn/wp-content/themes/begin/inc/inc.php on line 927
Warning: preg_match_all(): Compilation failed: missing closing parenthesis at offset 76 in /www/wwwroot/standards.biao-zhun.cn/wp-content/themes/begin/inc/inc.php on line 928
Warning: preg_match_all(): Compilation failed: unmatched closing parenthesis at offset 21 in /www/wwwroot/standards.biao-zhun.cn/wp-content/themes/begin/inc/inc.php on line 927
Warning: preg_match_all(): Compilation failed: unmatched closing parenthesis at offset 21 in /www/wwwroot/standards.biao-zhun.cn/wp-content/themes/begin/inc/inc.php on line 928
AWWA C207-18 pdf download.Steel Pipe Flanges for Waterworks Service, Sizes 4 In. Through 144 In. (100 mm Through 3,600 mm)
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. The selection of materials is critical for water service and distribution piping in locations where there is likelihood the pipe will be exposed to significant concentrations of pollutants composed of low-molecular-weight petroleum products or organic solvents or their vapors. Documented research has shown that pipe materials (such as polyethylene and 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 products. 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.
4.1.3 Manufacturing methods. Flanges shall be made from seamless forgings, cut from plate as a single piece, welded bar rings, or segmented and welded plates.
4.1.4.2. Minimum bolt lengths shall be determined by adding the sum of the mating flange maximum thicknesses, the gasket, washers, and the depth of the nut plus ¼-in. (6.4-mm) minimum. If studs with two nuts are used, they shall be the same length as the bolts determined previously, plus the depth of a second nut and washer, plus an additional 1 in. (3.2 mm). If studs with only one nut are used to mate to a flange with tapped holes, the studs shall be the same length as the bolts determined previously.
4.2.3 Drilling. For flanges up to 84 in. (2,100 mm) in diameter, bolt holes shall be drilled 1 in. (3.2 mm) larger in diameter than the nominal diameter of the bolt. For flanges larger than 84 in. (2,100 mm) in diameter, bolt holes shall be drilled 3/16-in. (4.8-mm) larger than the nominal bolt diameter. Bolt holes may be oversized by an additional 1 in. (3.2 mm) to accommodate insulators or to facilitate alignment with the mating flange. If bolt holes are oversized, washers shall be used.
4.2.4 Segmentation of flanges. Flanges shall be constructed by welding segments together when the OD of a flange exceeds the width of available plate material (approximately 78-in. [1,950-mm] ID and larger). The maximum number of segments in a single flange shall be four and segments shall be of approximately equal size.AWWA C207-18 pdf download.