To Wheel Brake
To Tank
FLUID POWER SYMBOLS
KENR5490-01 April 2010
From Pilot Accumulator
BASIC COMPONENT SYMBOLS
COMPONENT LIST MAIN AUX.
ITEM
NAME
450E (PILOT)
450E (MECH)
1
PUMP GP. (Primary)
269-9336
2
PUMP GP. (Secondary)
280-7873
3
HYDRAULIC TANK
280-7873
4
TANK GROUP
245-0169
5
COOLER
ATTACHMENT
LINE RESTRICTION VARIABLE and PRESSURE COMPENSATED
VALVES
FILTER
7
HMU
210-6240
8
STEER CYL.
238-5285
9
LIFT CYL.
125-7895
10
TILT CYL.
100-7844
Slave Cylinder
226-5540
12A
LH
270-7290
12B
RH
270-7291
13
BOOM CYLINDER
270-7285
14
STICK CYL.
270-7286
15
SWING
CYL.
286-8903
16
BUCKET CYL.
270-7287
17
E-STICK CYL (OPT).
Master Cylinder
Boost Brake Valve
VALVE PORTS
TWO POSITION
ONE POSITION
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.
CHECK VALVES
P T SHIFTED POSITION
INFINITE POSITION
PRESSURE
PILOT
267-2758
20
MANIFOLD - PILOT
268-0094
21
VALVE GP - CUSHION RELIEF
283-6331
22
ACCUMULATOR
226-0420
23
RIDE CNTRL VALVE (OPT)
245-8780
24
RIDE CNTRL ACCMLTR (OPT)
162-3960
25
RIDE CNTR PRES. SWTCH (OPT)
304-5696
26
TEMP. SENSOR
246-4297
27
DIFF. PRES. SWITCH
134-0404
PILOT CONTROLLED
ROTATING SHAFTS
FLOW
TEMPERATURE
UNIDIRECTIONAL
BIDIRECTIONAL
FLUID STORAGE RESERVOIRS
450E Backhoe Loader Hydraulic System
223-4715
PILOT - LEVER W/DTNT & SWTCH
SHUTTLE
SPRING LOADED
BASIC SYMBOL
MEASUREMENT
270-7288
18
FOUR-WAY
THREE-WAY
AB
P T NORMAL POSITION
VALVE GROUP ( 2-BANK) 19
TWO-WAY
THREE POSITION
CONTROL VALVES AB
STABILIZER CYLNDERS
12
PUMP: VARIABLE and PRESSURE COMPENSATED
2-SECTION PUMP
HYDRAULIC PNEUMATIC ENERGY TRIANGLES
VALVE ENVELOPES
6
MP BUCKET CYL.(OPT)
LINE RESTRICTION (FIXED)
RESTRICTION
PRESSURE COMPENSATION
LINE RESTRICTION (VARIABLE)
SPRING (ADJUSTABLE)
VARIABILITY
CONTROL VALVES
SPRING
FLUID CONDITIONER
N/A 307-9799
11
PUMP or MOTOR
VENTED
RETURN ABOVE FLUID LEVEL
PRESSURIZED
RETURN BELOW FLUID LEVEL
COMBINATION CONTROLS
EBL1-UP
SOLENOID
SOLENOID or MANUAL
SERVO
SOLENOID and PILOT or MANUAL
SOLENOID and PILOT
DETENT
THERMAL
MANUAL CONTROL SYMBOLS
LOADER VALVE 2 BANK
271-0512
3 BANK
271-0513
INLET SECTION
271-0520
28B
LIFT SECTION
271-0521
28C
TILT SECTION
271-0522
28D
AUX SECTION
271-0523
28E
OUTLET MANIFOLD
28A
28
A
29
8 BANK
271-0527
STABILIZER SECTION
271-0541
271-0531
29C
AUX SECTION
271-0547
271-0537
29D
BOOM SECTION
271-0542
271-0532
29E
STICK SECTION
271-0543
271-0533
29F
SWING SECTION
271-0544
271-0534
29G
BUCKET SECTION
271-0545
271-0535
29H
E-STICK SECTION
271-0546
271-0536
PEDAL
SPRING
PILOT CONTROL SYMBOLS REMOTE SUPPLY PRESSURE
INTERNAL RETURN
SIMPLIFIED
CROSSING AND JOINING LINES
ACCUMULATORS
299-9072
N/A
30
VALVE GP - CUTOFF
260-3022
31
PRESSURE REUDCING VALVE
300-0430
SPRING LOADED
FIXED DISPLACEMENT
Implement and Steering Pump
B
GAS CHARGED
LINES CROSSING
HYDRAULIC PUMPS
BOOSTED BRAKES
271-0539
OUTLET MANIFOLD
PUSH BUTTON
RELEASED PRESSURE
The master cylinders can be removed from the machine from inside the operator's compartment.
29B
PATTERN SWITCHING VALVE
GENERAL MANUAL
INTERNAL SUPPLY PRESSURE
COMPLETE
HYDRAULIC AND PNEUMATIC CYLINDERS
266-2558 269-1062
INLET SECTION
29K
MANUAL SHUTOFF
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.
271-0517
29A
29J
C
EXTERNAL RETURN
269-1079 271-0527
D
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.
BACKHOE VALVE 7 BANK
E
SINGLE ACTING
LINES JOINING
INTERNAL PASSAGEWAYS
HYDRAULIC MOTORS
VARIABLE DISPLACEMENT NON-COMPENSATED
FIXED DISPLACEMENT
VARIABLE DISPLACEMENT NON-COMPENSATED
UNIDIRECTIONAL
UNIDIRECTIONAL
BIDIRECTIONAL
BIDIRECTIONAL
DOUBLE ACTING
CROSS FLOW
PARALLEL FLOW
FLOW IN ONE DIRECTION
TWO POSITION
THREE POSITION
INFINITE POSITIONING
FLOW ALLOWED IN EITHER DIRECTION
Volume 1 of 2: Pilot (Center Pivot) A Printed in U.S.A.
© 2010 Caterpillar All Rights Reserved
Loader Valve
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
H
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.
Filter Bypass Switch
T3 View of pilot controlled backhoe valve with floor plate removed.
Pressure Switch (Adjustable)
Pressure Switch
Electrical Symbols (Electrical)
6
D
A
27 26 12
28 6
3
25 24 23
9 10
4
8
5
11
N
B
C
D
E
F
G
H
I
T
J
Pressure Symbol
T2 C
Electrical Wire
Temperature Switch
Temp Sensor
Filter Bypass Switch
SOS
HYDRAULIC OIL FILTER 29 22
Electric Motor
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.
15
Generator
Temp Sensor
Pilot Manifold
Oil Sampling
Transducer (Gas / Air)
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
17 16
14
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)
SOS
C
Transducer (Fluid)
M
30 Page
Pump Discharge Load Sense Pilot Pressure
G
KENR5490-01 VOL 1
Description
T1 T2 T3
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.
TAP LOCATIONS Tap
Electrical Symbols Table