Heves megyei aprónyomtatványok 20/B
PNEUMATIC VALVES 21 The control of pneumatic systems is provided by valves. The direction, velocity, power and sequence etc. of work components is determined by valves. Classification of valves By mode of control: — manually and mechanically By mode of function: — direct — pneumatically — indirect — electrically controlled I At direct valves the actuating part directly controls the closing part, at indirect valves the actuating part is connected to a pilot valve and the pneumatic signal of the pilot valve controls the closing part of the valve. Technical data See the relevant tables for each valve. Fluid Filtered (with a filter of pore dimension of 25 pm), oiled compressed air. Some valves can be used with other fluid too, like hydraulic oil. These are the following: type 144, 344, 345, 346. Working pressure range The range between the lowest necessary and the highest permissible pressure in which the valve or system in question have a reliable function. Control pressure range The range between the lowest necessary and the highes permissible pressure in which the valve or system in question have a reliable function. Actuating force The force which is necessary for a reliable function of a component in case of a supply pressure of 6,3 bar. Working temperature range The range of ambient and fluid temperature in which the component or system in question have a reliable function. This value at Mecman valves is (—20 °C/—10 °C to + 60 °C/+ 70 °C). Reference flow q ' ... 3 At 6,3 bar supply pressure the maximum quantity of air flowing through the valve is qmax 1/3 part of it is qr (Ndm Is). In case of right determination of connection port dimensions of valves the effective flow should be chosen between qr and 2xqr.
