©
2004 Caterpillar
All Rights Reserved
Printed in U.S.A.
RENR7038
August 2004
345B and 345B Series II Front Shovel
Bottom Dump Circuit
2SW1-UP
Hydraulic System
ONE POSITION
TWO POSITION
THREE POSITION
VENTED
PRESSURIZED
RETURN ABOVE FLUID LEVEL
RETURN BELOW FLUID LEVEL
LINES CROSSING
LINES JOINING
TWO-WAY
THREE-WAY
FOUR-WAY
SPRING
CONTROL VALVES
RESTRICTION
LINE RESTRICTION
(FIXED)
2-SECTION PUMP
MAIN
AUX.
SPRING
(ADJUSTABLE)
VARIABILITY
LINE RESTRICTION
(VARIABLE)
LINE RESTRICTION
(VARIABLE and PRESSURE COMPENSATED)
PRESSURE
COMPENSATION
PUMP: VARIABLE and
PRESSURE COMPENSATED
ENERGY TRIANGLES
HYDRAULIC PNEUMATIC
MEASUREMENT
PRESSURE
TEMPERATURE
FLOW
ROTATING SHAFTS
UNIDIRECTIONAL BIDIRECTIONAL
PUSH-PULL LEVER
PEDAL
GENERAL MANUAL
PUSH BUTTON
SPRING
MANUAL CONTROL SYMBOLS
HYDRAULIC MOTORS
FIXED
DISPLACEMENT
VARIABLE DISPLACEMENT
NON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
HYDRAULIC PUMPS
FLUID STORAGE RESERVOIRS
CROSSING AND JOINING LINES
VALVE ENVELOPES
VALVE PORTS
BASIC COMPONENT SYMBOLS
FLUID CONDITIONER
PUMP or MOTOR
FLUID POWER SYMBOLS
FIXED
DISPLACEMENT
VARIABLE DISPLACEMENT
NON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
VALVES
PILOT CONTROL SYMBOLS
RELEASED PRESSURE
EXTERNAL RETURN
INTERNAL RETURN
REMOTE SUPPLY PRESSURE
SIMPLIFIED
COMPLETE
INTERNAL
SUPPLY PRESSURE
ACCUMULATORS
SPRING LOADED
GAS CHARGED
SOLENOID
or MANUAL
SOLENOID
and PILOT
SOLENOID and
PILOT or MANUAL
COMBINATION CONTROLS
SOLENOID
SERVO
THERMAL
DETENT
HYDRAULIC AND PNEUMATIC CYLINDERS
DOUBLE ACTING
SINGLE ACTING
BASIC SYMBOL
SPRING LOADED
CHECK VALVES
TWO
POSITION
INFINITE
POSITIONING
FLOW IN ONE
DIRECTION
FLOW ALLOWED IN
EITHER DIRECTION
THREE
POSITION
CROSS
FLOW
PARALLEL
FLOW
INTERNAL PASSAGEWAYS
NORMAL POSITION
AB
PT
AB
PT
SHIFTED POSITION
INFINITE POSITION
CONTROL VALVES
CCC1-UP
Schematic
1
2
4
3
5
6
Pi8
PSA
PG
TOUT
DR1
DR2DR3
DR4
DR5
DR6
(SLOW)
Pi3
(TRAVEL)
(SWING)
PIN
PEU
(PUMP)
Pi1
Pi2
C/V
JPi
Pi5
(RELIEF)
PAC
(n1.2)
(n1.2)
(350k)
(370k)
(370k)
(370k)
(218k)
(370k)
(370k)
(370k)
PTA
B
A
DR1
MU
SWING
MOTOR
PG1
SWING
MOTOR
MU
DR2
A
B
PG2 P G3
STICK
SWING
BOOM
BUCKET
JR1
JR3
JR4
JR2
JRT
JRP
JL2
JL4
JL1
JL3
JLT
JLP
AR1
BR1
AL2
BL2
X
DR
HL
dL5
aL5
BL4
bL4
AL3
BL3
aL3
bL2
AL1
BL1
aL1
PSW
aR1
aR2
AR2
BR2
bR3
aR4
Y
HR
AR4
R1
dSW
bR2 bR1
PL
PR
Pp1
bL1
PAT
aL2
bL3 aL4
BOOM(1)
BUCKET
DUMP
TRAVEL(R)
PiL
aR3dR4
SA5
SA4
SA3
SA2
SA1
SB5
SB4
SB3
SB2
SB1
SP
(B)
(F)
(B)
(R)
(L)
SWING
(F)
(1.8k/-0.05k)
(40 MESH)
(DOWN)
(OPEN)
(FWD)
(FWD)
(L)
(IN)
(UP)
(CLOSE)
(UP)
(IN,OUT,DOWN)
dR5
(BACK)
(BACK)
(R)
AR3
(OUT)
BR3
R2
R3
APi2
PP2
STICK(1)
STICK(2)
BOOM(2)
TRAVEL(L)
TRACK
(OPEN)
(CLOSE)
TT
TP
TRAVEL(R)
TRAVEL(L)
TLA1
TLA2
TRA2
TRA1
PSL
APi
ADr
AL4
(COOLANT)
B
L
L1
S
(OIL)
X
T1
RIGHT
L'L'
B'
A'
BR
BR
MB
MA
MB
A'
B'
T1
LEFT
A'
B'
B
A
T2
X
T2
MA
B
A
X
T
S3
S2
S1
P
R1
S
R2
X1
X2
M3
X3
A1
M1
A2
M2
R1
A3
C
Pi3
)(
T
Pi1
Pi2
Dr1
OWD
X1
X2
Dr2
Bd1
Bd2
AB
C
T
Pi
A
Dr
X
A
Pi
)(
)(
)(
)(
Dr
X
C
B
A
214B214A
Dr
Pi
P2
P1
P1
P2
Dr
A2
A1
3
2
1
S2
This Attachment Schematic is intended to
be used in conjunction with the Standard
Hydraulic Schematic in this Service Manual.
Hydraulic Schematic
230-3370
PILOT LINE
DRAIN LINE
MAIN CONNECTOR LINE
g01098880
