ASME B16.44 pdf download

ASME B16.44 pdf download Manually Operated Metallic Gas Valves for Use in Aboveground Piping Systems Up to 5 psi
1 SCOPE
1.1 General This Standard applies to new valve construction and covers quarter turn manually operated metallic valves in sizes NPS 4 1 ⁄ 4 and tubing sizes 1 1 ⁄ 4 O.D. These valves are intended for indoor installation as gas shutoff valves when installed in aboveground fuel gas piping downstream of the gas meter outlet and upstream of the inlet connection to a gas appliance. The valves covered by this Standard are intended for service at temperatures between 32°F (0°C) and 125°F (52°C) at pressure ratings not to exceed 5 psi (0.34 bar). When so designated by the manufacturer, these valves may be installed for service outdoors and/or at temperatures below 32°F (0°C) and/ or above 125°F (52°C).
1.2 Applicability This Standard sets requirements, including qualifica- tion requirements, for metallic gas valves for use in gas piping systems. Details of design, materials, and testing in addition to those stated in this Standard that are necessary to meet the qualification and production test- ing requirements of this Standard remain the responsibility of the manufacturer. A valve used under a code jurisdiction or governmental regulation is subject to any limitation of such code regulations.
1.3 Limitations This Standard does not apply to manually operated gas valves that are an integral part of a gas appliance. Manually operated gas valves intended for use in a particular appliance are covered in ANSI Z21.15/ CGA 9.1.
1.4 Convention For determining conformance with this Standard, the convention for fixing significant digits where limits (maximum and minimum values) are specified shall be as defined in ASTM E29. This requires that an observed or calculated value be 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.
1 1.5 Quality Systems Requirements relating to the product manufacturer’s quality system programs are described in Nonmandatory Appendix A.
1.6 Relevant Units This Standard states values in both SI (Metric) and U.S. Customary units. These systems of units are to be regarded separately as standard. Within the text, the SI units are shown in parentheses. The values stated in each system are not exact equivalents; therefore, it is required that each system of units be used indepen- dently of the other. Combining values from the two systems constitutes nonconformance with the Standard. All pressures, unless otherwise specified, are gauge pressures.
2 GENERAL CONSTRUCTION AND ASSEMBLY
2.1 General Each valve at the time of manufacture shall be capable of meeting the requirements set forth in this Standard. The workmanship employed in the manufacture and assembly of each valve shall provide for the specified gas tightness, reliability of performance, freedom from injurious imperfections, and defects as specified herein.
2.2 End Connections The valve body shall be provided with wrench flats at ends with tapered pipe threads.
2.3 Pipe and Tubing Connections
2.3.1 Taper Pipe Threads. Taper pipe threads, when provided, shall be in accordance with ASME B1.20.1.
2.3.2 Flare Tubing Connection. Valves with an inlet and/or outlet for 3 ⁄ 8 , 1 ⁄ 2 , or 5 ⁄ 8 O.D. tube shall be in accor- dance with the flare fitting dimensions shown in Table 1. Other flare sizes shall be made per manufacturer’s standards. 2.4 Operating Head The operating head of the valve shall be a lever, tee, flat, or square head type. Separately attached handles, if provided, shall be securely attached to the valve by the use of threaded fasteners, retaining pins, or their equivalent.
2.5 Operation The valve shall require one-quarter turn from the full closed position to the full open position, or from the full open position to the full closed position.
2.6 Position Indication The valve shall be so constructed that the operator can visually determine that the valve is in the open or closed position. When the valve is in the closed position, the operating lever or flow indicator shall be perpendic- ular to the longitudinal axis of the valve.
2.7 Tamperproof Features Where valves are specified to be tamperproof, they shall be designed and constructed to minimize the possi- bility of the removal of the core of the valve with other than specialized tools (i.e., tools other than common wrenches, pliers, etc.).