C700-77: AWWA Standard for Cold-Water Meters--Displacement Type (PDF)

This standard covers the various types and classes of cold water displacement meter in sizes 5/8-6 in., and the materials and workmanship employed in their fabrication. The displacement meters covered, known as nutating-disc or oscillating-piston meters, are positive in action, in that the pistons and discs displace or carry over a fixed quantity of water for each nutation or oscillation when operated under positive pressure. Included are sections on the following: references, affidavit of compliance, basis for rejection, materials, pressure castings, main castings, register box rings and lids, pistons and discs, measuring chamber diaphragms, pistons, spindles, thrust rollers, and thrust roller bearing plates, intermediate gear trains, covers (breakable top and bottom), coupling tail-pieces and nuts, and companion flanges. Also covered are the following types: general design including size, capacity, length, pressure requirement, frost protection devices, external case closure and fastenings, accessibility, registration accuracy, markings; detailed design of cases, connections, registers, register boxes, intermediate gear trains, measuring chambers, pistons and discs, strainers, and seal wire holes. The appendix contains information on units of measurement, register types, tests, testing equipment, registration accuracy, periodic tests, and meter storage.