scope:

Valve Types

This Standard covers requirements for manually operated metallic valves in nominal sizes 2½ (DN 65) through 12 (DN 300) having the inlet and outlet on a common centerline. These valves are intended for controlling the flow of gas from open to fully closed positions, for use in distribution and service lines where the maximum gage pressure does not exceed 125 psig (8.6 bar). Valve seats, seals, and stem packing may be nonmetallic.

Application

This Standard sets forth the minimum capabilities, characteristics, and properties that a newly manufactured metallic valve must possess in order to be considered suitable for use in piping systems indicated above, carrying natural gas, manufactured gas [includes synthetic natural gas (SNG)], and liquefied petroleum gases (distributed as a vapor, with or without the admixture of air) or mixtures thereof.

Referenced Standards

Standards and specifications adopted by reference in this Standard and the names and addresses of the sponsoring organizations are shown in Mandatory Appendix I. It is not considered practical to refer to a specific edition of each of the standards and specifications in the individual references. Instead, the specific edition references are included in Mandatory Appendix I. A product made in conformance with a prior edition of reference standards will be considered to be in conformance, even though the edition reference may be changed in a subsequent revision of the standard.

Quality Systems

Nonmandatory requirements relating to the product manufacturer's Quality System Program are described in Nonmandatory Appendix A.

Convention

For the purpose of determining conformance with this Standard, the convention for fixing significant digits where limits, maximum or minimum values, shall be "rounded off" as defined in ASTM Practice E 29. This requires that an observed or calculated value shall be rounded off to the nearest unit in the last right-hand digit used for expressing the limit. Decimal values and tolerances do not imply a particular method of measurement.

Codes and Regulations

A valve used under the jurisdiction of a Federal Regulation, such as CFR Title 49, Part 192; the ASME Code for Pressure Piping, such as ASME B31.8; or the National Fuel Gas Code, Z223.1, is subject to any limitation of that code or regulation.

Definitions

NPS: nominal pipe size

NVS: nominal valve size

one bar: 100 kPa

PTFE: materials that comply with ASTM D 4894, Specification for Polytetrafluoroethylene (PTFE) Granular Molding and Extrusion Materials

All pressures, unless otherwise stated, are gage pressures.