ASME B16.40 pdf download

ASME B16.40 pdf download.MANUALLY OPERATED THERMOPLASTICGAS SHUTOFFSAND VALVES IN GAS DISTRIBUTION SYSTEMS.
(a) ASME B16.40 covers manually operated iherinoplastic valves in nominal sizes 1/2 through 6 (as shown in Table 5). These valves are suitable for use below ground in thermoplastic distribution mains and service lines. The maximum pressure at which such distribution piping systems may be operated is in accordance with the Cede of Federal Regulation (CFR) Title 49. Part 192. Transportation of Natural and Other Gas by Pipeline; Minimum Safety Standards, for tempcratrure ranges of
—2O’F to 100°F (—29°C to 38°C).
(h) This Standard sets qualification requirements for each nominal valve size for each 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 natural gas lincludes synthetic natural gas (SNG)I. and liquefied petroleum (LPI gases (distributed as a vapor, with or without the admixture of air) or mixtures thereof.
(d) Standards and Specifications referenced under this Standard are shown in Appendix II.
(e) 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 “rounding off’ as defined in ASTM Practice E 29. 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. 1)ecimal values and tolerances do not imply a particular method of measure me nt.
b) The values stated in either inch units 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 front the two systems may result in nonconformance with the standard.
1.1 Definitions
fasteners: nuts, bolts, washers, clip rings, and other devices used in the assembly of valves.
The valve shall then be opened against the appliedditierential pressure. using a torque less than or equal to that of Table 3 at the —20°F (—29°C) values and then closed (no differential pressure across the seat required). The valve shall then be tested to meet the requirements of para. 3.3.2 while at —20°F (—29°C). except nonfreezing leak-detection agents shall be used. The valve shall then be heated to a temperature of 1(X) ± 5°F (38 ± 3°C) and held there for 18 hr minimum. The closed valve shall then be pressurized with air or other gas to a differential pressure across the seat equal to the design pressure. The valve shall then be opened against the applied-differential pressure using a torque equal to that of Table 3 100°F (38°C) values and then closed (no differential pressure across the seat required.). The valve shall then be tested to and meet the requirements of para. 3.3.2. while at 100°F (38°C).
3.3.3 Sustained-Pressure Test. Each basic valve design shall be subjected to sustained-pressure tests to determine the effects of 1,0(X) hr pressure loading. Each variation in material, size. or configuration of molded pressure-containing parts shall constitute a different basic design. Where minor design variations are produced by differences in machining of valve-end connections to match pipe of different size or Sl)R rating. only valves with the lowest SDR rating (corresponding to the SDR equivalent rating of the valve) and in the largest site need to be tested.
(a) Pressure-Boundary Tests. Six samples of each basic valve design shall be connected at both ends to thcnnopla.stic pipe of appropriate wall thickness of a length of at least five Limes its outside diameter or 20 in. (510 mm), whichever is less. These assemblies shall be subjected to a sustained-pressure tes for 1.000 hr (valves in open position), using water at 73 ± 4°F (23 ± 2°C) as described in the Sustained-Pressure Test section of ASTM D2513.