… Taps, cocks, valves and similar appliances for pipes, boiler shells, tanks, vats or the …
Explanatory notes
… by opening or closing an aperture (e.g., gate, disc, ball, plug, needle or diaphragm). They may be operated by hand (by … In general, taps, valves, etc., are of base metal or plastics, but those of other materials ( other than … adjustable tension thermostatic element, which actuates the plugs or stoppers regulating the admission of fluids at …