ASME B16.40:2019 pdf free download – Manually Operated Thermoplastic Gas Shutoffsand Valves in Gas Distribution Systems
1.1 General
(a) This Standard covers manually operated thermo-plastic valves in nominal valve sizes ‘h2 through 12.These valves are intended for use below ground in ther-moplastic fuel gas distribution mains and service lines.The maximum operating pressure (MOP) at whichsuch distribution piping systems may be operated is inaccordance with Transportation of Natural and OtherGas by Pipeline;Minimum Safety Standards [49 C.F.R..s192 (2017)] for temperature ranges of -20°F to140°F (-29C to 60°C).
(b) This Standard sets qualification requirements foreach basic valve design as a necessary condition fordemonstrating conformance to this Standard.
(c) This Standard sets requirements for newly manu-factured valves for use in below-ground piping systems forfuel gas [includes synthetic natural gas (SNG)]and lique-fied petroleum (LP) gases (distributed as a vapor, with orwithout the admixture of air) or mixtures thereof.
1.2 References
Standards and specifications adopted by reference areshown in Mandatory Appendix l1, which is part of thisStandard.It is not considered practical to identify the spe-cific edition of each standard and specification in the text.Instead, the specific edition referenced is identified inMandatory Appendix ll1.
1.3 Convention
For determining conformance with this Standard, theconvention for fixing significant digits where limits(maximum and minimum values) are specified shall beas defined in ASTM E29.This requires that an observedor calculated value be rounded off to the nearest unit in thelast right-hand digit used for expressing the limit. Decimalvalues and tolerances do not imply a particular method ofmeasurement.
1.4 Relevant Units
This Standard states values in both U.s.Customary andSl (metric) units.These systems of units are to be regardedseparately as standard.Within the text, the Sl units areshown in parentheses.The values stated in eachsystem are not exact equivalents; therefore, it is required
that each system of units be used independently of theother. Combining values from the two systems constitutesnonconformance with the Standard.
1.5 Definitions
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basic valve design: each variation in material, size,or
configuration of molded pressure-containing parts thatconstitutes a given valve design, except where minordesign variations are produced by differences inmachining of the same molded piece(s) to producedifferent end sizes or dimensional ratios (DRs).
DR: the dimensional ratio defined as the pipe outsidediameter (o.D.) divided by the pipe wall thickness, t.DR = 0.D./t.
DRv: the valve DR equivalent is the designated valve DRbased on the lowest DR of the pipe ends used in long-termhydrostatic testing under this Standard.ASTM D2513shall be the standard used for polyethylene (PE) andASTM F2945 shall be the standard for polyamide 11(PA-11).
fasteners: nuts,bolts, washers,clip rings,and other devicesused in the assembly of valves.
lubricated valves: valves that require pressure lubrication(by the insertion through fittings of lubricantto the sealingsurfaces of the valve) to effect a leak-tight seal.
NVS: nominal valve size.
pressure: unless otherwise stated, gage pressure.
production pressure tests: tests that include seat andclosure-member and shell tests.
seat and closure-member test: an internal pressure test ofclosure-sealing elements (seats, seals, and closuremembers,e-g-. gate, disc, ball, or plug).
shell test: an internal pressure test of the pressure-containing envelope.
valve design pressure: the pressure calculated by themethod described in Mandatory Appendix I using thevalve shell material’s hydrostatic design basis (HDB) at73F (23°C).