Abstract： ASME B16.40:2008 pdf download.Manually Operated Thermoplastic Gas Shutoffs and Valvesin Gas Distribution Systems. 2.2 MaterIals 2.2.1 Valve Shell. The pressure-containing valve shell shall be made from either polyethylene (PE) or polvamide...

ASME B16.40:2008 pdf download.Manually Operated Thermoplastic Gas Shutoffs and Valvesin Gas Distribution Systems.

2.2 MaterIals

2.2.1 Valve Shell. The pressure-containing valve shell shall be made from either polyethylene (PE) or polvamide 11 (PA-Il)

materials specified in and qualified to the requirements for pipe and fittings as listed in ASTM D 2513.

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 stern 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.

Recommended：