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Table P001-2/E
Hydraulic symbols
PUMPS
Graphic symbol
(a)
Description
Item
(b)
One flow direction (a)
Fixed displacement pump
Two flow directions (b)
(a)
(b)
One flow direction (a)
Variable displacement pump
Two flow directions (b)
Hand pump
Lever pumping
Item
Description
MOTORS
Graphic symbol
(a)
(b)
One rotation direction (a)
Fixed displacement motor
Two rotation directions (b)
(a)
(b)
One rotation direction (a)
Variable displacement motor
Two rotation directions (b)
Hydraulic motor with
Rotary actuator
limited angle of rotation
CYLINDERS
Item
Graphic symbol
(a)
(b)
Description
Return stroke by external force (a)
Single-acting cylinder
Return stroke through a spring (b)
(a)
(b)
Single rod (a)
Double-acting cylinder
Double rod (b)
(a)
(b)
Cylinder with fixed
stroke end cushioning
(a)
(b)
Cylinder with adjustable
stroke end cushioning
(a)
Cushioning on one side (a)
Cushioning on both sides (b)
Cushioning on one side with adjustment (a)
Cushioning on both side with adjustment (b)
(b)
Single-acting (a)
Telescopic cylinder
Double-acting (b)
PRESSURE CONTROL VALVES
Pressure relief valve
Direct operated
Pilot operated
Pressure reducing valve
Direct operated
Sequence valve
Direct operated
Pilot operated
Counterpressure valve
Pilot operated
P001
FLOW CONTROL VALVES
Variable throttling valve
Two way
Compensated flow regulator
With check
Two-way
Three-way
DIRECTIONAL CONTROL VALVES
Check valves
Piloted operated
without spring
With spring,
normally closed
Piloted with drain
2 ways - 2 positions
3 ways - 2 positions
Detent
Pushbutton
Lever
Adjustable stroke limiter
Spring
Cam
Electric (solenoid)
Electro-hydraulic
Pneumatic
Hydraulic
Electric (proportional)
Electro-hydraulic (proportional)
Directional valves (spool type)
4 ways - 2 positions
4 ways - 3 positions
Controls for directional valves
ENERGY TRANSMISSION AND ACCESSORIES
Graphic symbol
Item
Description
Graphic symbol
Item
Description
Pipings above level
Electric
Motor
Reservoir
Engine
Pipings under level
Pressurized reservoir
Main
(a)
Pilot
(b)
Spool position sensor Mechanical microswitch (a)
on-off
Inductive proximity sensor (b)
Hydraulic
accumulator
Drain
Pipings and
Filter
connections
Flexible hose
Heater
Connection point
Heat exchanger
Cooler
Crossing
Liquid operated cooler
Closed
Pressure gauge
Branching
With connected piping
Pressure switch
Fast coupling
Coupling
Rotating shaft
With check valves
05/08
1 direction
2 directions