This standard includes requirements for valves fitted with internal body, plug, and port linings or applied hard facings on the body, body ports, plug, and plug port. The extent of linings and the facing materials of which they are made are not covered in this standard.
This standard also provides additional requirements for plug valves that are in full conformance to the requirements of ASME B16.34 for Standard Class 150 through 2500. Ductile iron valves, Class 150 and 300, shall follow the additional requirements of ASME B16.42 for pressure-temperature ratings, wall thickness, flange dimensions, and material grade.
Plug valves covered in this standard belong to one of four general design groups that in many cases have different face-to-face and end-to-end dimensions. Some types of plug valves are not made to all patterns. The four groups of valve design are described below.
The standard nomenclature for valve parts is shown in Annex B. Figure B.1, Figure B.2, Figure B.3, and Figure B.4 illustrate typical plug valve designs and are not to be construed as precluding other available designs that comply with the requirements of this standard. The only purpose of these figures is to identify part names. The construction of a valve is acceptable only when it complies with this standard in all respects.