ASME B16.40-2013 pdf – Manually Operated Thermoplastic Gas Shutoffs and Valves in Gas Distribution Systems
ASME B16.40-2013 pdf – Manually Operated Thermoplastic Gas Shutoffs and Valves in Gas Distribution Systems.
(a) This Standard covers manually operated ttwrmoplastic valves in nominal valve sizes through 12. liwse valves are intended for use below ground in thermoplas.tic fuel gas distribution mains and service lines. The maximum operating pressure (MOP) at which such distribution piping systems may be operated is in accordance with the Code of Federal Regulations (CFR) Title 49. Part 192. Transportation of Natural and Other Gas by Pipeline; Minimum Safety Standards, for temperature ranges of -2rF to 140F (—29CC to OC),
(7) This Standard sets qualification requirements for each basic valve design as a necessary condition for demonstrating conformance to this Standard.
(C) This Standard sets requirements for newly manufactured valves for use in below-ground piping systems for fuel gas lincludes synthetic natural gas (SNG)I and liquefied petroleum (Li’) gases (distributed as a vapor. with orwithout tlwadmixtureof air) or m,xturesthercof.
Standards and specifications referenced under this Standard are shown in Mandatory Appendix IL
For the purpose of determining conformance with this Standard, the convention for fixing significant digits. where limits maximum or minimum values are specified, shall be “rounded ocr as defined in ASIM Practice E2’J. 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
1.4 Relevant Units
11w values staled in either inch or metric units are to be regarded separately as standard, Within the text the values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the Standard.
fa) The workmanship used In the manufacture and assembly of each valve shall pnwide gas tightness. safety arid reliability of performance, and freedom from iniuriDes imperfections and defects.
(Zi) Design detaiLs not addressed in this Standard are the responsibility of the manufacturer.
2.2.1 Valve Shell, The pressure-containing valve shril shall be made from either polyethylene (PE) or 1w,Iyamlde 11 (PA-lI) materials specified In and qualifIed IL) 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-tei-m pressure-containment intcgrty ci,nsistent with the valve shell. The sustained prs-ssLIrv tests of para. 6.33 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 consideratioris, it is the users’ responsibility to specify this information to the manufacturer.
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 thert-on 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 avis 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.
(1) Valves designed for more than one-quarter turn operation shall close isv clockwise stem rotation, unless otherwise specified by the user. The direction for closing the valve shall be indicated.