ASME B16.40:2002 pdf free download

ASME B16.40:2002 pdf free download.MANUALLY OPERATED THERMOPLASTIC GAS SHUTOFFS AND VALVESIN GAS DISTRIBUTION SYSTEMS.
(a) ASME B16.40 covers manually operated thermoplastic valves in nominal sizes 14 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 Code of Federal Regulation (CFR) Title 49. Part 192. Transportanon of Natural and Other Gas by Pipeline:
Minimum Safety Standards, for temperatrure ranges of
—20’F to l0O°F (—29°C to 38°C).
(b) This Standard sets qualification requirements for each nominal valve size br each valve design as a necessary condition for demonstrat ins conformance to this Standard.
(C) This Standard sets requirements for newly manufactured valves for use in below ground piping systems for natural gas Iindudcs synthetic natural gas (SNG)I. and liquefied petroleum (LP) gases (distributed as a vapor, with or withow 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 confonnance 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 he 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.
If) 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 from the two systems may result in nonconformance with the standard.
1.1 Definitions
fasienerx: nuts, bolts, washers, clip rings, and other devices used in the assembly of valves.
The valve shall then be opened against the applieddifferential 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 he 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 lOtY 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 SDR rating. only valves with the lowest SDR rating (corresponding to the SDR equivalent rating of the valve) and in the largest size need to be tested.
(a) Pre.csure-Boundwy Test.. Six samples of each basic valve design shall be connected at both ends to thermoplastic pipe of appropriate wall thickness of a length of at least five times us outside diameter or 20 in. (510 mm). whichever is less. These assemblies shall be subjected to a sustained-pressure test for 1.000 hr (valves in open positiorn. using water at 73 ± 4°F (23 ± 2°C) as described in the Sustained-Pressure Test section of ASTM D 2513. The SDR equivalent for the valve shall he used in determining the test pressure from Table 4A. Failure of two of the six samples tested shall constitute failure in the Lest. Failure of one of the six samples tested is cause for retest of six additional samples. Failure of one of the six samples in retest shall constitute failure in the test. Evidence of failure shall be as defined in ASTM I) 1598 applied to a valve test sample.
An additional six samples of each basic valve design shall also be subjected to a similar sustained-pressure test for 1.000 hr. using water at a temperature of 100 ± 4°F (38 ± 2°C) and an appropriate test pressure from Table 4B. Criteria for failure shall he the same as described above for the 73°F (23°C) test.