To Wheel Brake
To Tank
FLUID POWER SYMBOLS
UENR0270-01 November 2012
From Pilot Accumulator
BASIC COMPONENT SYMBOLS
COMPONENT LIST (PILOT) 269-9336
1
B-4
PUMP GP. (Secondary)
280-7873
2
B-3
HYDRAULIC TANK
272-0008
3
A-3
TANK GROUP
245-0169
4
A-3
N/A
5
A-3
FILTER
307-9799
6
B-2
HMU
297-1590
7
A-5
STEER CYLNDER
238-5285
8
A-6
LIFT CYLNDER
125-7895
9
C-8
TILT CYLNDER
100-7844
10
B-8
MP BUCKET CYLNDER (OPT)
226-5540
11
B-8
Left Hand
270-7290
12A
F-3
Right Hand
270-7291
12B
F-7
BOOM CYLINDER
270-7285
13
F-6
STICK CYLNDER
270-7286
14
F-5
SWING
CYLNDER
297-4896
15
F-5
BUCKET CYLNDER
270-7287
16
F-4
E-STICK CYLNDER (OPT).
270-7288
17
F-4
COOLER
STABILIZER CYLINDERS
223-4715
18
C-5
PILOT
267-2758
19
C-4
MANIFOLD - PILOT
268-0094
20
C-6
VALVE GP - CUSHION RELIEF
283-6331
21
F-4
ACCUMULATOR
226-0420
22
E-7
RIDE CNTRL VALVE (OPT)
245-8780
23
D-8
RIDE CNTRL ACCMLTR (OPT)
162-3960
24
D-8
RIDE CNTR PRES. SWTCH (OPT)
304-5696
25
D-8
TEMP. SENSOR
246-4297
26
B-3
DIFF. PRES. SWITCH
134-0404
27
B-3
Slave Cylinder
Master Cylinder
Boost Brake Valve
450E Backhoe Loader Hydraulic System
A
271-0520
28A
C-7
LIFT SECTION
271-0521
28B
C-7
28D
B-7
28E
28E
E
D
C
29
F-7, F-2
8 BANK
271-0528
29
F-7, F-2
INLET SECTION
341-4726
29A
E-7
271-0541
29B
E-3
Right Hand 271-0541
29B
E-7
AUX SECTION
271-0547
29C
E-6
BOOM SECTION
271-0542
29D
E-6
STICK SECTION
341-8185
29E
E-5
SWING SECTION
271-0544
29F
E-5
BUCKET SECTION
271-0545
29G
E-4
E-STICK SECTION
271-0546
29H
E-3
OUTLET MANIFOLD
271-0539
29J
E-2
PATTERN SWITCHING VALVE
299-9072
29K
E-5
VALVE GP - RELIEF
260-3022
30
E-2
PRESSURE REUDCING VALVE
300-0430
31
E-7
MANUAL SHUTOFF
GAS CHARGED
FIXED DISPLACEMENT
LINES CROSSING
SINGLE ACTING
LINES JOINING
FIXED DISPLACEMENT
UNIDIRECTIONAL
BIDIRECTIONAL
BIDIRECTIONAL
DOUBLE ACTING
INTERNAL PASSAGEWAYS
VARIABLE DISPLACEMENT NON-COMPENSATED
UNIDIRECTIONAL
CROSS FLOW
PARALLEL FLOW
FLOW IN ONE DIRECTION
TWO POSITION
THREE POSITION
INFINITE POSITIONING
FLOW ALLOWED IN EITHER DIRECTION
Printed in U.S.A.
The hydraulic oil filter is located below the machine at the left frame rail. The hydraulic oil filter bypass switch is mounted to the oil filter base.
T2
Electrical Symbols Table Hydraulic Symbols (Electrical)
The pilot manifold can also be accessed with the floor plate removed. The pilot pressure tap (T3) is located on the pilot manifold. The pilot manifold routes pilot oil to and from the loader and backhoe pilot control valves.
H
G Transducer (Fluid)
Transducer (Gas / Air)
View of pilot controlled backhoe valve with floor plate removed.
Pressure Switch (Adjustable)
Pressure Switch Temp Sensor
Filter Bypass Switch
SOS
Electrical Symbols (Electrical)
6
N
B
C
D
E
F
G
H
I
J
Pressure Symbol
T2 C
Electrical Wire
Temperature Switch
T
27 26 11
Electric Motor
Filter Bypass Switch
T3
A 5
Generator
SOS
The implement and steering pump is located below the floor plate in the cab. The pump control valve (H) contains a torque control spool adjustment screw (B) and a flow compensator adjustment screw (A). The adjustment screws and the load sensing pressure tap (T2) are accessible from the cab.
8
M
Temp Sensor
The implement and steering pump on the 450E machines is similar to the "D" Series machines, but now includes a torque control solenoid (not visible). The torque control solenoid provides an additional pump setting.
9 10
HYDRAULIC AND PNEUMATIC CYLINDERS
HYDRAULIC MOTORS
VARIABLE DISPLACEMENT NON-COMPENSATED
INTERNAL SUPPLY PRESSURE
COMPLETE
Volume 1 of 2: Pilot (Center Pivot)
Pilot Manifold
4
SIMPLIFIED
Loader Valve
Oil Sampling
3
SPRING
© 2011 Caterpillar All Rights Reserved
Pump Discharge Load Sense Pilot Pressure
25 24 23
PEDAL
A
Description
28 6
PUSH BUTTON
CROSSING AND JOINING LINES
D
12
DETENT
THERMAL
REMOTE SUPPLY PRESSURE
HYDRAULIC PUMPS
HYDRAULIC OIL FILTER 29 22
GENERAL MANUAL
INTERNAL RETURN
SPRING LOADED
TAP LOCATIONS
15
SERVO
SOLENOID and PILOT or MANUAL
SOLENOID and PILOT
ACCUMULATORS
Implement and Steering Pump
C
SOS
RETURN BELOW FLUID LEVEL
PILOT CONTROL SYMBOLS
The master cylinders can be removed from the machine from inside the operator's compartment.
B
271-0527
T1 T2 T3
BIDIRECTIONAL
RELEASED PRESSURE
BOOSTED BRAKES
7 BANK
Tap
UNIDIRECTIONAL
RETURN ABOVE FLUID LEVEL
SOLENOID or MANUAL
PUSH-PULL LEVER
B
The brake boost valves are connected to the master cylinder (A) at each brake pedal (B). Oil enters the master cylinder through the supply hose (C) and exits the master cylinder through the return hose (D). The oil flows to the service brakes through the hoses (E) at the bottom of the master cylinder.
BACKHOE VALVE
Left Hand
SOLENOID
B-7
269-1079
FLOW
COMBINATION CONTROLS
EXTERNAL RETURN
INLET SECTION
271-0523
PILOT CONTROLLED
ROTATING SHAFTS
PRESSURIZED
The 450E machines are equipped with hydraulically assisted master cylinders, which decreases the amount of pedal effort when braking. This illustration shows the boosted brakes valve group, which uses oil from the pilot accumulator to add boost to the master cylinder. The hydraulic force multiplies the pedal effort so the operator can get more braking force with less effort.
A-7, C-7
AUX SECTION
SHUTTLE
SPRING LOADED
BASIC SYMBOL
MANUAL CONTROL SYMBOLS
28
OUTLET MANIFOLD
INFINITE POSITION
TEMPERATURE
VENTED
RBA1-UP LYR1-UP
271-0513
STABILIZER SECTION
P T SHIFTED POSITION
P T NORMAL POSITION
FLUID STORAGE RESERVOIRS
3 BANK
28C
CHECK VALVES
AB
PRESSURE
A-7, C-7
271-0522
FOUR-WAY
THREE-WAY
MEASUREMENT
28
3 BANK
TWO-WAY
THREE POSITION
CONTROL VALVES
This illustration shows a sectional view of the boosted brake valve group. When the brake pedal is depressed, the boost brake valve moves to the left and inlet oil from the pilot manifold is directed to the master cylinder.
271-0512
TILT SECTION
VALVE PORTS
TWO POSITION
ONE POSITION
AB
2 BANK
271-0522
ATTACHMENT
LINE RESTRICTION VARIABLE and PRESSURE COMPENSATED
VALVES
LOADER VALVE (ST)
2 BANK
HYDRAULIC PNEUMATIC ENERGY TRIANGLES
VALVE ENVELOPES
VALVE GROUP ( 2-BANK) PILOT - LEVER W/DTNT & SWTCH
PRESSURE COMPENSATION
LINE RESTRICTION (VARIABLE)
SPRING (ADJUSTABLE)
VARIABILITY
PUMP: VARIABLE and PRESSURE COMPENSATED
2-SECTION PUMP
Flow Symbol
Level Symbol
Temperature Symbol
Wire Number Identification Codes
T1
14
Electrical Schematic Example
SOS
16 15
Implement and Steering Pump
E G
Hydraulic Schematic Example Current Standard
Current Standard
Hydraulic Oil Filter
Harness identification code This example indicates wire 135 in harness "AG".
Wire Circuit Number Identification
Loader Valve
13
Wire Color
325-AG135 PK-14
14
A
12 18 19
1
7
10
9
325-PK Circuit Identification Number
T2
11
Wire Color
Wire Gauge
L Previous Standard
B Drain
14
17 16
18 19
1
3
4
10
5
C
K
Wire Color
Wire
D
B
C
E
A
325-PK-14 B
M Circuit Number Identification
D B
C
D
A
Wire Gauge (EXAMPLE VALVE)
P E
R
EIGHT BANK VALVE (PILOT OPERATED) The 450E machines are equipped with a pilot controlled backhoe valve that is visible with the floor plate at the rear of the cab removed.
F
M This illustration shows a eight bank backhoe valve. The components in the backhoe valve are:
J
Drain
13
(A) Outlet Manifold (B) Left Stabilizer Control Valve (C) Extendable Stick Control Valve (D) Bucket Control Valve (E) Swing Control Valve (F) Stick Control Valve (G) Boom Control Valve
T1
15
E
12
29 22
26 28 6
25 24 23
7
9
8
11
Note: The auxiliary Control Valve (H) is not avalible on the optional seven bank valve.
Torque control adjustment (A), Flow compensator adjustment (B), Load sensing pressure tap (T2), Inlet port (C), Case drain port (D), Torque control solenoid (E), Discharge pressure tap (T1), Torque limiter (F), Outlet port (G) For other bank valve configurations see KENR5488 (Specifications Manual).
NOTE: Alpha numeric numbers are represented by the number only on the machine views.
COMPONENT LOCATIONS
IMPLEMENT / STEERING PUMP
1
BACKHOE VALVE 29
B
N
THREE BANK VALVE:
(H) Auxiliary Control Valve (I) Right Stabilizer Control Valve (J) Pilot On/Off Solenoid Valve (K) Inlet Manifold (L) A Ports (M) B Ports (N) Load Signal Relief Valve
27 These illustrations show the implement and steering pump out of the machine. The following components are visible:
K
F
View of mechanically controlled loader valve with floor plate removed.
A
Travel at high speeds over rough terrain causes bucket movement. The optional Ride Control System acts as a shock absorber by absorbing bucket forces, which stabilize the machine.
The 450E machines are equipped with a mechanically controlled loader valve as shown in this illustration.
The Ride Control System components include; ride control relay (A), ride control solenoids (B), ride control accumulator (C), and ride control pressure switch (D).
The loader valve is accessed from below the floor plate. The loader control valve group contains:
Two solenoids are now used on the "E" Series machines Ride Control System.
(A) Outlet manifold. (B) Auxiliary control valve. (C) Tilt control valve. (D) Lift control valve. (E) Inlet manifold. (F) Load signal relief valve.
(J) Makeup and relief valve. (K) Magnetic detent for return to dig function. (M) Priority Valve. (N) Mechanical detent for the float. (P) A ports. (R) B ports.
D
The Ride Control System, on machines with the optional autoshift transmission, is controlled by the Machine ECM. The Machine ECM monitors the position of the ride control switch and determines when to operate the ride control system.
C
ECM
For other bank valve configurations see KENR5488 (Specifications Manual).
LOADER VALVE 28
RIDE CONTROL 23
24 25
(Dimensions: 39 inches x 28 inches)
PUMP GP. (Primary)
LINE RESTRICTION (FIXED)
RESTRICTION
30 Page
Description
Machine Schematic Location Location
CONTROL VALVES
SPRING
FLUID CONDITIONER
UENR0270-01 VOL 1
Part Number
MAIN AUX.
PUMP or MOTOR