scope:

This standard describes iron-body, brass-mounted, nonrising-stem (NRS) gate valves including tapping gate valves, 3 in. (75 mm) NPS through 48 in. (1,200-mm) NPS, (Footnote *) and outside screw and yoke (OS&Y) rising-stem gate valves, 3 in. (75-mm) NPS through 12 in. (300- mm) NPS, with either double-disc gates having parallel or inclined seats, or solid-wedge gates. These valves are suitable for use in approximately level settings in water systems. These valves are intended for applications where fluid velocities do not exceed 16 ft/sec (4.9 m/sec) when the valve is in the full open position.

Valve pressure ratings. The design working water pressure shall be 200 psig (1,380 kPa) for valves 12-in. (300-mm) NPS and smaller, and 150 psig (1,050 kPa) for valves with diameters of 16-in. (400-mm) NPS and larger. Valves for operating pressures that fall outside these limits are beyond the scope of this standard and require special consideration in design and construction.

Conditions and materials not described. This standard is not intended to describe special conditions of gate-valve installation or operation, such as built-in power drive, installation in vertical or steeply inclined lines, conveyance of unusually corrosive water, excessive water hammer, frequent operation (as in filter service), or operation in a throttled position. Such conditions are beyond the intended scope of this standard and require special consideration in design and construction. Joint accessories for end connections, such as bolts, gaskets, glands, follower rings, and so forth, are not described in this standard.

Footnote * Valves 14-in. (350-mm) NPS and 18-in. (450-mm) NPS are not considered standard-size valves and are not described in this standard.

Purpose

The purpose of this standard is to provide purchasers, manufacturers, and suppliers with the minimum requirements for reduced-wall, metal-seated gate valves for water supply service, including materials, design, testing, inspection, rejection, marking and shipping.

Application

This standard can be referenced in specifications for purchasing and receiving reduced-wall, metal-seated gate valves for water supply service. The stipulations of this standard apply when this document has been referenced and then only to reduced-wall, resilient-seated gate