AWWA C509-23 PDF

This standard describes iron-body resilient-seated gate valves with nonrising stems (NRS) and outside screw-and-yoke (OS&Y) rising stems, including tapping gate valves, for water supply service having a temperature range of 33–125°F (0.6–52°C).

1.1.1 Velocity. These valves are intended for applications where fluid velocity does not exceed 16 ft/s (4.9 m/s) when the valve is in the full-open position. 
1.1.2 Sizes. Gate valves described by this standard are 3–72 in. (75–1,800 mm) nominal pipe size (NPS). 
1.1.3 Valve pressure rating. The minimum design working water pressure shall be 200 psig (1,380 kPa [gauge]) for 3–12 in. (75–300 mm) sizes and 150 psig (1,034 kPa [gauge]) for 14–72 in. (350–1,800 mm) sizes. 
1.1.4 Conditions and materials not covered. This standard is not intended to describe special conditions of gate valve installation or operation, such as built-in power drive, installation in unusually corrosive soil, conveyance of unusually corrosive water, excessive water hammer, frequent operation (as in filter service), or operation in a throttled position. These conditions are beyond the intended scope of this standard and require special consideration in design and construction.