ASME B16.40:2019 pdf free download – Manually Operated Thermoplastic Gas Shutoffsand Valves in Gas Distribution Systems
2.1 General
(a) The workmanship used in the manufacture andassembly of each valve shall provide gas tightness,safety and reliability of performance, and freedomfrom injurious imperfections and defects.
(b) Design details not addressed in this Standard arethe responsibility of the manufacturer.
2.2 Materials
2.2.1 Valve ShelL. The pressure-containing valve shellshall be made from either PE or PA-11 materials specifiedin and qualifled to the requirements for pipe and fittings aslisted in ASTM D2513 or ASTM F2945.
2.2.2 Parts Other Than the Valve Shell. Parts otherthan the valve shell that contribute to pressure contain-ment or retaining differential pressure across the closureelement shall be resistant to the gases in para.1.1[c).Suchparts shall be designed to withstand normal valve-oper-ating loads and, in addition, shall provide long-term pres-sure-containment integrity consistent with the valve shell.The sustained pressure tests of para.6.3.3 shall qualify thedesign and material selected for these parts, whichinclude, 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 andsealants shall be resistant to the action of gases referredto 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 asgases having high hydrogen content or compounds likelyto form condensate, dictate special materials considera-tions, it is the user’s responsibility to specify this informa-tion to the manufacturer.
3 CONFIGURATION3.1 Operating Indication
a) valves designed for one-quarter turn operationshall be designed to visually show the open and closedposition of the valve.A rectangular stem head with anarrow thereon or a separate position indicator shall indi-cate the ciosed position of the vaive port when the ion-gitudinai axis of the stem head or indicator isperpendicular to the axis of the connecting pipe.If a sepa-rate indicator is used, it shall be designed such that itcannot be assembled to incorrectly indicate the positionof the valve.
6.2 Production Testing
6.2.1 Shell Test.Each valve shall be tested at 4 psi ± 2psi (0.28 bar±0.14 bar) and at a minimum of 1.5 times thedesign pressure.The test pressure shall be applied to allpressure-containing areas of the valve (including stemseals and valve ends).This may require the valve to bein the partially open position. The shell test shall beconducted at a temperature of 73F ±15°F (23°C土8°C).The test fixturing shall not restrain the valveagainst any mode of failure or leakage.The minimumduration of each of the two shell tests shall be asshown in Table 6.2.1-1.
6.2.2 Seat Test.Each valve shall be seat closure testedat 4 psi±2 psi (0.28 bar±0.14 bar) and ata minimum of1.5times the valve design pressure.These pressures shall beapplied successively on each side of the valve seat(s) tocheck the valve-sealing performance in both directions.The seat test shall be conducted at a temperature of73F ±15F (23C± 8°C). The seat test”s fixturing shallnot restrain the valve against any mode of failure orleakage.The minimum duration of each portion of thetest shall be as shown in Table 6.2.1-1.