ASME B16.40:2013 pdf free download

ASME B16.40:2013 pdf free download.Manually Operated Thermoplastic Gas Shutoffs and Valves in Gas Distribution Systems.
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 requirement.s 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 bead 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.