SENR8330 December 1995
FLUID POWER SYMBOLS
BASIC COMPONENT SYMBOLS
MAIN AUX.
PUMP or MOTOR
FLUID CONDITIONER
SPRING
CONTROL VALVES
RESTRICTION
LINE RESTRICTION (FIXED)
2-SECTION PUMP
PUMP: VARIABLE and PRESSURE COMPENSATED
VARIABILITY
SPRING (ADJUSTABLE)
LINE RESTRICTION (VARIABLE)
PRESSURE COMPENSATION
HYDRAULIC PNEUMATIC ENERGY TRIANGLES
LINE RESTRICTION
VARIABLE and PRESSURE COMPENSATED
ATTACHMENT
VALVES
VALVE ENVELOPES VALVE PORTS
ONE POSITION
TWO POSITION
THREE POSITION
TWO-WAY
THREE-WAY
FOUR-WAY
CONTROL VALVES
CHECK VALVES
No.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
HYDRAULIC SYSTEM COMPONENTS DESCRIPTION
Steering Motor Group Steering Pump Group Steering Pilot Valve Group Bulldozer Dual Tilt Cylinder Group Bulldozer Lift Cylinder Group Quick-Drop Valve Bulldozer Tilt Cylinder Group Steering Charge Loop Filter Group Tank Group Cover Bulldozer Tilt Valve Bulldozer Lift valve Ripper Valve Inlet Manifold Ripper Lift / Tilt Valve Pilot Operated Relief Valve Charging Relief Valve
AB
AB
P T NORMAL POSITION
P T SHIFTED POSITION
INFINITE POSITION
BASIC SYMBOL
SPRING LOADED
SHUTTLE
PILOT CONTROLLED
MEASUREMENT
ROTATING SHAFTS
PRESSURE
TEMPERATURE
FLOW
UNIDIRECTIONAL
BIDIRECTIONAL
FLUID STORAGE RESERVOIRS
D8R Track-Type Tractor Hydraulic System
7XM1-UP 9EM1-UP
VENTED
PRESSURIZED
RETURN ABOVE FLUID LEVEL
RETURN BELOW FLUID LEVEL
COMBINATION CONTROLS
SOLENOID
SOLENOID or MANUAL
SOLENOID and PILOT
SOLENOID and PILOT or MANUAL
SERVO
THERMAL
DETENT
MANUAL CONTROL SYMBOLS
PUSH-PULL LEVER
MANUAL SHUTOFF
GENERAL MANUAL
PUSH BUTTON
PEDAL
SPRING
Implement Pump Group Bypass / Pressure Control Valve
RELEASED PRESSURE
PILOT CONTROL SYMBOLS
REMOTE SUPPLY PRESSURE
Cooler Ripper Tip Cylinder Ripper Lift Cylinder Ripper Diverter Valve Pin Puller Cylinder
EXTERNAL RETURN INTERNAL RETURN SIMPLIFIED COMPLETE INTERNAL SUPPLY PRESSURE
ACCUMULATORS
CROSSING AND JOINING LINES
HYDRAULIC AND PNEUMATIC CYLINDERS
SPRING LOADED
GAS CHARGED
LINES CROSSING
LINES JOINING
SINGLE ACTING
DOUBLE ACTING
HYDRAULIC PUMPS
FIXED DISPLACEMENT VARIABLE DISPLACEMENT NON-COMPENSATED
HYDRAULIC MOTORS
FIXED DISPLACEMENT VARIABLE DISPLACEMENT NON-COMPENSATED
INTERNAL PASSAGEWAYS
INFINITE POSITIONING THREE POSITION TWO POSITION
UNIDIRECTIONAL
UNIDIRECTIONAL
CROSS FLOW
BIDIRECTIONAL
BIDIRECTIONAL
FLOW IN ONE DIRECTION
PARALLEL FLOW
FLOW ALLOWED IN EITHER DIRECTION
1995 Caterpillar All Rights Reserved
Printed in U.S.A.
Electrical Symbols Table
Hydraulic Symbols (Electrical)
G
Transducer (Fluid) Transducer (Gas / Air) Generator
M
Electric Motor
PRESSURE TAP LOCATIONS LETTER DESCRIPTION
A B C D E F G H J K L M N P R S T U V W Right Steer Loop (at Motor) Right Steer Loop (at Pump) Left Steer Actuator Right steer Actuator Left Steer Loop (at Motor) Left Steer Loop (at Pump) Charge Pump Relief Control Supply Right Steer Pilot Left Steer Pilot Ripper Pilot Case Return Charge Pump Discharge Charge Pump Relief Cooler Implement Pump Discharge (at Valve) Implement Pump Signal (at Valve) Implement Pump Signal Implement Pump Discharge Downstream Filter
T
Pressure Switch
Pressure Switch (Adjustable)
Temperature Switch
Electrical Wire
Pressure Symbol
Temperature Symbol
Level Symbol
Flow Symbol
Wire Number Identification Codes Electrical Schematic Example
Current Standard
Harness identification code This example indicates wire 135 in harness "AG". Wire Circuit Number Identification Wire Color
Hydraulic Schematic Example
Current Standard
325-AG135 PK-14 325-PK
Circuit Identification Number Wire Color Wire Gauge
Previous Standard
Wire Wire Color
325-PK-14
B
Circuit Number Identification Wire Gauge
(EXAMPLE VALVE)
12 Page, DGM
Electrical Symbols (Electrical)
SENR8330-00
F
3
24 E F G H
E
22 20 21 23 5 M N P R 19 L 6
D
5 22 4
21 17 16 T
18 U
S 15 V
14
13
SENR8330-00
12 Page, Color 2, DGM
7 12
9 W
LINE PATTERNS
Pressure Line Pilot / Load Sensing Pressure Drain / Return Lines
11
Component Group Attachment Air Line
HYDRAULIC CIRCUIT COLOR DESCRIPTIONS
8
YY
CALLOUTS
Taps (Pressure, Sampling,Sensor) by letter Components by number
10
Steering Pump Output. Implement Pump Output. Ripper Cylinder Group. Supply Line. Drain / Return Line. Dual Tilt Cylinder Group Lift Cylinder Group Tilt Cylinder Group Steering Pilot Valve Group Load Sensing Pin Puller Cylinder
52
THIS SCHEMATIC IS FOR THE D8R TRACK-TYPE TRACTOR
Components are shown installed on a fully operable machine with the key and engine off and transmission shifter in neutral.
