Standard Fittings for Compressed Gas Cylinders

STANDARD FITTINGS FOR COMPRESSED GAS CYLINDERS Thomas J. Bruno and Paris D.N. Svoronos... 

Container valve connections that do not fit must not be forced. Threads on regulator connections or other auxiliary requirements must match those on the container valve outlet. The valve outlet connection should conform to recognized standards such as ANSI/CGA V-1, American National, Compressed Gas Association Standard for Compressed Gas Cylinder Valve Outlet and Inlet Connections [14]. However, it must be acknowledged that connections other than those found in ANSI/CGA V-1 may exist. If a user chooses such a connection, extreme care must be taken to ensure that such connections do not cross-connect with existing connections in ANSI/CGA V-1, and that they have been properly engineered for the intended gas service and pressure. The threads on a cylinder valve outlet, as well as on regulators and other ancillary equipment, should be examined at frequent intervals to ensure they are clean and undamaged. 

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