F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
F16K17/00—Safety valves; Equalising valves, e.g. pressure relief valves
F16K17/20—Excess-flow valves
F16K17/22—Excess-flow valves actuated by the difference of pressure between two places in the flow line
F16K17/24—Excess-flow valves actuated by the difference of pressure between two places in the flow line acting directly on the cutting-off member
F16K17/26—Excess-flow valves actuated by the difference of pressure between two places in the flow line acting directly on the cutting-off member operating in either direction