UL 147A:2018 free download Nonrefillable (Disposable) Type Fuel Gas Cylinder Assemblies
9 Assembly
9.1 A nonrefillable cylinder assembly shall include all of the components required for its intended functionand installation,and shall be furnished as a single unit or assembly.
9.2 The cylinder assembly shall be provided with an integral shutoff valve that closes automatically whenthe cylinder assembly is disconnected from the gas-consuming equipment.
9.3 The valve stem shall be recessed, or otherwise protected so that the valve is not subjected to directimpact when the container is dropped onto a flat surface.
9.4 The cylinder assembly shall incorporate a Type CGA No.600 connection in accordance with theCompressed Gas Association Standard for Compressed Gas Cylinder Valve Outlet and Inlet Connections,cGA v-1-2003.
9.5 A nonrefillable metal container assembly shall incorporate pressure relief device(s) or system(s) thatwill operate to reduce the risk of rupture or propulsion of container parts from pressure buildup from a firecondition.See the Fire Test,Section 16.
10 Materials
10.1 Operating and pressure-containing parts of shutof and relief valve assemblies shall have thestrength and durability to provide reliable service of the assembly.
10.2 To comply with the requirement of 10.1, a material for gas-confining parts shall have a melting point(solidus temperature) of at least 950°F (510°C) and a tensile strength of at least 10,000 psi (68.9 MPa)at 204°C (400°F).
Exception: A valve disc，soft seat, seal ring, diaphragm,or gasket is not required to comply with thisrequirement.
10.3 Materials shall be resistant to the action of the fuel gas to which they are exposed to duringservicing.
10.4 With reference to the requirement in 10.3, elastomeric and polymeric materials shall be subjected tothe Accelerated Aging Test,Section 17, the Fuel Gas Compatibility Test,Section 18, and the LowTemperature Test, Section 19.
Exception: Chlorotrifluoroethylene polymers，tetrafluoroethylene，fluorinated ethylene propylenepolymers，and polyamides with a composition of polyhexamethylene adipamide or polycapromidepolymers (nylon 6 or 6/6) are not prohibited from being used without additional testing.
10.5 lf atmospheric corrosion of a ferrous part impairs the intended operation, the part shall be providedwith a corrosion-resistant protective coating.
10.6 A protective coating shall resist corrosion to the degree not less than that provided by the protectivecoatings specified in 10.7.
10.7 Cadmium plating shall have a thickness of not less than 0.0003 inch(0.008 mm), and zinc platingshall have a thickness of not less than 0.0005 inch (0.013 mm).
Exception: When threads constitute the major portion of the area of a part, the thickness of the cadmiumor zinc plating shall not be less than 0.00015 inch (0.0038 mm).
10.8 A fuel-confining part of an inlet or relief valve that is made of drawn brass or machined from a brassrod made of copper alloy containing more than 15 percent zinc and incorporating internal threads shallwithstand without cracking, the Moist Ammonia-Air Stress Cracking Test, Section 20.
10.9 Parts made of metals having widely varying coefficients of thermal expansion and exposed to heatshall not be used in combination when threaded together with the intent to reduce the risk of externalleakage of fuel.
10.10 Copper or brass materials containing more than 67 percent copper shall not be used for parts incontact with MPS-Gas.
10.11 A brazing material used for joining parts of a cylinder assembly shall have a melting point (solidustemperature) not less than 1000°F(538 C).
UL 147A:2018 free download
