scope:

a. This standard covers steel plug valves with flanged or buttwelding ends, in nominal sizes of 1 to 24 in. corresponding to nominal pipe sizes (NPS) in ANSI B36.10.

b. This standard covers valves in nominal pressure ratings of 150 to 2500 lb as in ANSI B16.5.

c. The valve is the lubricated or nonlubricated type having two-way coaxial ports. This standard is intended to include valves fitted with internal body or port liners or applied hard facings on either bodies, body ports, plugs, or plug ports. The material and extent of liners is not covered herein and must be stated in the purchase order when desired.

Three-way and four-way plug valves are not included in this standard.

d. Plug valves covered by this standard are classified under four general design groups as follows:

1. Short Pattern:

The short pattern design has the same face-to-face dimensions as 150 and 300 lb flanged steel gate valves, corresponding to those in ANSI B16.10.

2. Regular Pattern:

As the plug ports in the regular pattern design are larger, the body, although designed as nearly as possible for streamline flow, does not approach the shape of a venturi throat. In this type, the plug port area is substantially greater than for the venturi valve.

3. Venturi Pattern:

Valves of the venturi pattern shall be designed for minimum pressure loss consistent with the reduced port area used in this type of valve, and shall have a conjunction of body and plug ports approximating a venturi throat.

4. Round-Port Full-Bore Pattern:

The round-port full-bore pattern shall have a circular port through both plug and body equal to at least the inside diameter of the comparable ANSI B16.5 fitting.

The standard nomenclature for valve parts is shown in Fig. 1. Although the figure indicates a lubricated design, nonlubricated valves may be similar, except for the omission of the lubrication groove and the substitution of mechanical means for freeing the plug.