Essential Symbols for Pneumatic Systems

Pneumatic Component Symbols

This article provides a comprehensive guide to the essential symbols used in pneumatic systems, focusing on directional flow control valves, valve actuators, pneumatic cylinders, vacuum components, and air filtration and regulation devices. These symbols are crucial for accurately designing and interpreting pneumatic schematics.

Directional flow control valves

Table 1: Pneumatic valve types and symbols

Component description Symbol
2/2-way valve, closed normal position
symbol
2/2-way valve, open normal position symbol
3/2-way valve, closed normal position symbol
3/2-way valve, open normal position symbol
3/3-way valve, closed neutral position symbol
4/2-way valve symbol
4/2-way valve, closed neutral position symbol
4/2-way valve, exhaust neutral position symbol
5/2-way valve symbol
5/3-way valve, closed neutral position symbol
5/3-way valve, exhaust neutral position symbol
5/3-way valve, open neutral position symbol
Check valve symbol

symbol

Pilot-operated check valve symbol
Adjustable flow control valve symbol
Solenoid direct symbol

Read our solenoid valve symbols article for more details on the functions, symbols, and application examples of solenoid valves in fluid power diagrams and piping and instrumentation diagrams (P&ID).

Pneumatic valve operator symbols

Table 2: Pneumatic valve actuator types and symbols

Description Symbol
General manual symbol
Push button symbol
Pull button symbol
Push/pull button symbol
Lever symbol
Pedal symbol
Plunger symbol
Spring symbol
Roller symbol
Unidirectional symbol
Pressure symbol
Differential pressure symbol

Pneumatic cylinder types

Table 3: Pneumatic cylinder types and symbols

Component description Symbol
Single-acting cylinder, front spring symbol
Single-acting cylinder, rear spring symbol
Single-acting cylinder, front spring with position sensing symbol
Single-acting cylinder, rear spring with position sensing symbol
Single-acting cylinder, front spring, through rod with position sensing symbol
Double-acting cylinder, fixed mechanical cushioning symbol
Double-acting cylinder, fixed mechanical cushioning with position sensing symbol
Double-acting cylinder, adjustable cushioning symbol
Double-acting cylinder, adjustable cushioning with position sensing symbol
Double-acting cylinder, self adjusting cushioning with position sensing symbol
Double-acting cylinder, through rod, fixed mechanical cushioning symbol
Double-acting cylinder, through rod, fixed mechanical cushioning with position sensing symbol
Double-acting cylinder, through rod, fixed mechanical cushioning, hollow piston rod symbol
Double-acting cylinder adjustable cushioning with position sensing symbol
Rodless cylinder, double-acting, fixed cushioning with position sensing symbol
Rodless cylinder, double-acting, adjustable cushioning with position sensing symbol
Rodless cylinder, double-acting, self adjusting cushioning with position sensing symbol
Single-acting rotary cylinder symbol
Double-acting rotary cylinder symbol
Bellows cylinder symbol
Clamping cylinder symbol
Rotary indexing table symbol
Double-acting parallel gripper symbol
Double-acting angular grippers symbol
Single-acting parallel gripper (NC) symbol
Single-acting angular gripper (NO) symbol
Inductive proximity sensor (2-wire) symbol

Vacuum components

Table 4: Vacuum components and symbols

Component description Symbol
Vacuum generator symbol
Vacuum generator with silencer symbol
Vacuum suction cup symbol

Air filtration and regulation

Table 5: Air filtration and regulation components and symbols

Component description Symbol
Filter symbol
Filter with manual drain symbol
Filter with automatic drain symbol
Vacuum filter symbol
Coalescing filter without drain symbol
Coalescing filter with manual drain symbol
Coalescing filter with automatic drain symbol
Filter regulator, manual drain symbol
Filter regulator, automatic drain symbol
Filter regulator, automatic drain, pressure gauge symbol
Lubricator symbol
Regulator with relieving symbol
Regulator, return flow and pressure gauge symbol
Electrical pressure regulator with gauge symbol
Air filter, regulator, and lubricator (FRL) symbol
Pressure gauge symbol
Shut-off valve symbol
Soft start valve symbol

Miscellaneous components

Table 7: Miscellaneous pneumatic components

Component description Symbol
Silencer symbol
Manifold (Branching module/distributor) symbol