Overall dimensions and technical information are provided solely for informative purposes and may be modified without notice. XXIV Pneumatic symbols VALVES AND SOLENOID VALVES - Terms and descriptions - The connections to the inlet and out lets of the valves can be of two types: - main connections : - supply connection identified with number 1 - consumption connection identified with number 2 and 4 - exhaust connection identified with number 3 and 5 - Pilot connections : - repositioning connection on 2/2 & 3/2 ways valves identified with number 10 - switching connection on 2/2 & 3/2 ways valves and repositioning connection on 5/2 & 5/3 ways valves identified with number 12 -switching connection on 5/2 & 5/3 ways valve identified with number 14 Switching : is the process that changes the state of a valve from rest position to actuated position and is achieved by means of a mechanical, pneumatic or electric signal Repositioning : is the process that changes the valve state from actuated back to rest position and is achieved by means of an external mechanical (spring), pneumatic (differential) or electric signal Ways : indicated the number of connections on the valve body and on the pneumatic diagram Positions : indicates the number of positions achieved by the valve and corresponds to the number of squares on the pneumatic simple. Function : indicates the valve working diagram at rest condition and corresponds to the right square in the pneumatic scheme. 2 2 Normally closed 2 2 Normally open 3 2 3 2 Normally open 5 2 Separated exhaust connections 5 3 Closed centres 5 3 5 3 Normally closed Open centres Pressured centres Differential (pneumatic spring) Differential external pilot Sensitive differential Lever Lever - spring to center Sensitive lever Two position mechanical stop Pedal Pedal - spring return Pneumatic Pneumatic - depressurised Pneumatic -return to center Push Button Unidirectional roller Plunger Bistable solenoid Solenoid with suppl. pilot Solenoid Solenoid (external pilot) Roller Sensitive roller Sensitive push button Sensitive plunger Push button - two positions-. Solenoid (internal pilot) Solenoid - spring to center Spring Three position mechanical stop Valves symbols Function Way Pos. Symbol Switching and Repositioning Mechanical Electrical Pneumatics Complementary valves Piping and connections 2 1 2 1 2 1 3 2 4 1 3 5 15 3 1 3 2 2 4 2 4 315 4 15 2 3 Pressure line Control line Exhaust line Flexible line Electric line Piping connections Piping intersection Main air connection One-way rotating intake Three-way rotating intake Closed air intake Air intake with connection Quick coupling connection without non-return valve Quick coupling connection with non-return valve Air exhaust unthreaded connection Air exhaust threaded connection Silencer Non-return valve without spring Non-return valve with spring Non-return valve controlled during closing Non-return valve controlled during opening Throttle valve Bidirectional flow regulator Unidirectional flow regulator Quick exhaust valve Shuttle valve 03