Resilient Seat Wedge Gate Valves 1. Valve shall conform to AWWA C509-87, Standard for resilient Seated Gate Valves. 2. Wedge shall be constructed of cast or ductile iron, fully encapsulated in synthetic rubber. 3. Wedge rubber shall be molded in place and bonded to the iron portion, and shall not be mechanically attached with screws, rivets, or similar fasteners. 4. Wedge shall seat against seating surface arranged symmetrically about the center line of the operation stem, so that seating is equally effective regardless of the direction of pressure unbalance across the wedge. 5. All seating surfaces in the body shall be inclined to be vertical at a minimum angle of 32 degrees (when stem is in a vertical position) to eliminate abrasive wear of rubber sealing surfaces. 6. Stem shall be sealed by at least two O-rings; all stem seals shall be replaceable with valve fully open and wile subject to full rated pressure. 7. Waterway shall be smooth and shall have no depressions or cavities in seat area where foreign material can be lodged and prevent closure or sealing. 8. Valve body and bonnet shall be epoxy coated, inside and out, with fusion bonded epoxy. Coating shall conform to AWWA C550-90, Standard for Protective Interior Coatings for Valves and Hydrants. 9. Gate valves shall be Mueller A2360, AFC 500, AVK 25/00, or M & H style 7000. Butterfly Valves Butterfly valves and operators shall conform to AWWA standards for rubber-seated butterfly valves, AWWA Standard C504, and to these specifications: 1. Type of body shall be short body, flanged or mechanical joint. 2. Body material shall be cast iron or ductile iron. 3. Class shall be specified on the plans or contract specifications. 4. Shaft shall be type 304 or 316 stainless steel. 5. Flanged holes shall be drilled to full size. 6. Valve seat shall be natural rubber or Buna-N and polished stainless steel, type 304 or 316, 90-degree seating angle only, with a 360-degree, uninterrupted seating surface. 7. Shaft seals shall be standard split-V packing or double O-ring seal cartridges. 8. Disc shall be ductile iron, cast iron, or fabricated steel. 9. Operating nuts shall be ductile iron.
