ASME B16.33 pdf download

ASME B16.33 pdf download.MANUALLY OPERATEDMETALLIC GAS VALVES FORUSE IN GAS PIPING SYSTEMS
UP TO125 PSI.
ASME B16.33 covers requirements for manually operated metallic valves sizes NPS /, through NPS 2. for outdoor installation as gas shut-off valves at the end of the gas service line and before the gas regulator and meter where the designated gauge pressure of the gas piping system does not exceed 125 psi (8.6 bar). The Standard applies to valves operated in a temperature environment between —2OF and l5OF (—29°C and 66°C).
1.2 Design
This Standard sets forth the minimum capabilities. characteristics, and properties, which a valve at the time of manufacture must possess. in order to be considered suitable for use in gas piping systems. Details of design and manufacture (other than those stated in this Standard, including such design and production tests that will produce a valve that will huve the required capabilities to meet this Standard) remain the responsibility of the manufacturer.
1.3 Standards and Specifications
Standards and specifications adopted by reference in this Standard and the names and addresses of the sponsoring organizations are shown in Nonmandatory Annex A. It is not considered practical to refer to a specific edition of each of the standards and specifications in the individual references. Instead the specific edition references arc included in Nonmandatory Annex A. A product made in conformance with a prior edition of reference standards and in all other aspects conforming to this Standard will be considered to be in conformance even though the edition reference may be changed in a subsequent revision of this Standard.
4 DESIGN QUALIFICATiON
4.1 General
4.1.1 Each basic valve design shall be qualified and demonstrated as suitable for the service by testing randomly selected production salves of each size, type and pressure shell material according to the design qualification tests.
4.1.2 All teas, unless otherwise specified, shall be conducted at a temperature of 74°F ± I 5°F (23°C ± 8°C).
4.1.3 Before each test is conducted, the valve shall be in the condition in which it would be placed in service.
4.2 Gas Tightness
4.2.1 The valve shall provide a shut-off when in the closed position and shall not leak to the atmosphere in the open or closed position when subjected progressively to internal air pressure of first 4 ± 2 psi (0.3 + 0.1 bar) and then to at least 1.5 iins the pressure rating of the valve.
4.2.2 Method of Test for Gas Tightness. With the valve in the open position and the outlet plugged. the test pressure shall be applied to the inlet of the valve. The valve shall be immersed in a bath containing water at a temperature of 74°F ± 15°F (23°C ± 8°C) for a period of IS seconds. Leakage. as evidenced by flow (breaking away) of bubbles shall not be permined. The valve shall then he turned to the closed position. outlet opened and the test repeated.
4.2.3 Other means of leak detection may be used provided they can he shown to be equivalent in leak detection sensitivity.
4.3 Temperature Resistance
4.3.1 A valve should be operable at emperawres ranging from —20°F to 150°F (—29°C to 66°C) without affecting the capability of the valve to control the flow of gas.
4.3.2 The valve shall be maintained at a temperature of —20°F (—29°C) for a period long enough to allow all parts to come to equilibrium temperature. With the valve subjected to an internal air pressure am least equal to the pressure rating and with the outlet end of the valve arranged to vent to atmosphere, it shall he determined that it can be opened and closed.
4.4.3 Twist. The valve body. when tested in both the open and closed position, shall withstand the torque specified in Table 2 applied directly to the ends of the valve, without rup4ure or permanent delorination that would, after release of the torque, render the valve inoperable, incapable of providing a shut-off, or cause it to leak to atmosphere when tested as outlined in para. 4.2.
4.4.4 Bending. A valve in both the open and closed positions shall withstand the bending moment specified in Table 3 when applied as indicated in Fig. I. without rupture. After the bending stress is relieved, there shall be no permanent dekrmation that would render the valve inoperable, incapable of providing a shut-off.