ASME B16.40-2013 pdf download

ASME B16.40-2013 pdf download.Manually Operated Thermoplastic Gas Shutoffs and Valvesin Gas Distribution Systems.
1.5 Definitions
basic valve design: for a given valve design, each variation in material, size, or configuration of molded pressure- containing parts shall constitute a different basic valve design, except where minor design variations are produced by differences in machining of the same molded piece(s) to produce different end sizes or dimensional ratios (DRs).
DR: the dimensional ratio defined as the pipe outside diameter (O.D.) divided by the pipe wall thickness, 1. DR = O.D./t.
DRy: the valve DR equivalent is the designated valve
DR based on the lowest DR of the ASTM D2513 pipe
ends used in long-term hydrostatic testing under this
Standard.
fasteners: nuts, bolts, washers, clip rings, and other devices used in the assembly of valves.
lubricated valves: valves that require pressure lubrication to effect a leak-tight seal (by the insertion through fittings of lubricant to the sealing surfaces of the valve).
NVS: nominal valve size.
pressure: unless otherwise stated, pressure is gage pressure.
production pressure tests: pressure tests that include seat and closure-member and shell tests.
seat and closure-member test: an internal pressure test of closure-sealing elements (seats, seals, and closure members, such as gate, disc, ball, or plug).
shell test: an internal pressure test of the pressure- containing envelope.
valve design pressure: the pressure calculated by the method described in Mandatory Appendix I using the valve shell material’s Hydrostatic Design Basis (HDB) at 73°F (23°C).
1.6 Quality Systems
Nonmandatory requirements relating to the product manufacturer’s Quality System Program are described in Nonmandatory Appendix A.
2 CONSTRUCTION
2.1 General
(a) The workmanship used in the manufacture and assembly of each valve shall provide gas tightness, safety and reliability of performance, and freedom from injurious imperfections and defects.
(b) Design details not addressed in this Standard are the responsibility of the manufacturer.
2.2 Materials
2.2.1 Valve Shell. The pressure-containing valve shell shall be made from either polyethylene (PE) or polyamide 11 (PA-Il) materials specified in and qualified to the requirements for pipe and fittings as listed in ASTM D2513.
2.2.2 Parts Other Than the Valve Shell. Parts other than the valve shell, which contribute to pressure containment or retaining differential pressure across the closure element, shall be resistant to the gases in para. 1.1(c). Such parts shall be designed to withstand normal valve-operating loads and, in addition, shall provide long-term pressure-containment integrity consistent with the valve shell. The sustained pressure tests of para. 6.3.3 shall qualify the design and material selected for these parts, which include, but are not limited to, the closure member, stems or shafts (if they are designed to retain pressure), and fasteners retaining shell sections.
2.2.3 Lubricants and SeaLants. Lubricants and seal- ants shall be resistant to the action of gases referred to in para. 1.1(c). Lubricated valves, as defined in para. 1.5, are not within the scope of this Standard.
2.2.4 Responsibility. When service conditions, such as gases having high hydrogen content or compounds likely to form condensate, dictate special materials considerations, it is the users’ responsibility to specify this information to the manufacturer.
3 CONFIGURATION
3.1 Operating Indication
(a) Valves designed for one-quarter turn operation shall be designed to visually show the open and closed position of the valve. A rectangular stem head with an arrow thereon or a separate position indicator shall indicate the closed position of the valve port when the longitudinal axis of the stem head or indicator is perpendicular to the axis of the connecting pipe. If a separate indicator is used, it shall be designed such that it cannot be assembled to incorrectly indicate the position of the
valve
(b) Valves designed for more than one-quarter turn operation shall close by clockwise stem rotation, unless otherwise specified by the user. The direction for closing the valve shall be indicated.