C509-87: AWWA Standard for Resilient-Seated Gate Valves for Water and Sewerage Systems

This standard covers iron-body resilient-seated gate valves with nonrising stems and outside screw-and-yoke rising stems for installation in water and sewerage systems. Gate valves covered in this standard are 3 in., 4 in., 6 in., 8 in., 10 in., and 12 in., in nominal pipe size (NPS). Sizes refer to the nominal diameter, in inches, of the waterway through the inlet and outlet connections and the closure area. The design working pressure shall be 200 psig for all sizes. General information regarding definitions used, documents referenced, data to supplied by manufacturer and affidavits of compliance is supplied. The section on materials covers the physical and chemical properties of the following valve components: gray cast iron, ductile cast iron, steel brass or bronze, gaskets, O-rings, paint, and elastomers. General design concerns addressed are resistance to stress, basis of structural design, and size of waterway. The section on detailed design covers the following topics: parts to be made of gray or ductile cast iron, parts to be made of brass or bronze, bodies and bonnets, bonnet bolting, valve ends, guides, stems and stem nuts, stem sealing, packing, wrench nuts and handwheels, gaskets, valve seats, seat reinforcement, glands, and gland bolts and nuts. The discussion of fabrication examines workmanship, castings, painting and coating. Information related to testing, inspection, and rejection as well as marking and shipping is presented. An appendix describes the installation, operation and maintenance of resilient-seated valves. The history of the standard and information regarding use of the standard is presented in the foreword.