SECTION 6

HYDRAULIC SYSTEM
TABLE OF CONTENTS
Location of Main Hydraulic Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Hydraulic Circuits and Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Hydraulic Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Component Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Location of Hydraulic Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11
Hydraulic System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-17
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-17
Outline. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-17
Oil Flow From No.1 and No.2 Pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-18
Oil Flow From No.3 and No.4 Pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-19
Oil Flow From No.5 Pump (Control Pump) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-20
Oil Flow From No.6 Pump (Secondary Pump) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-20
Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-25
4-Section Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-25
8-Section Valve (With Shuttle Valve) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-26
4-Section Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-27
3-Section Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-28
5-Section Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-29
2-Section Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-30
1-Section Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-31

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SECTION 6
HYDRAULIC SYSTEM
LOCATION OF MAIN HYDRAULIC
COMPONENTS

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HYDRAULIC CIRCUITS AND COMPONENTS

Hydraulic Circuit

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Component Specifications

Item Name of Component Specification

Pump (Front & Rear Drum, Propel) Swash Plate Type, Variable Capacity
1 [K3V112DT] Max. Delivery : 252 L / min 2
Set Pressure : 31.9 MPa
Pump (Swing / Boom) Swash Plate Type, Varible Capacity
[K3V112DT]
Swing Boom
3
Max. Delivery 175 L / min 252 L / min

Set Pressure 27.5 MPa 32.0 MPa

Gear Pump (Control / Aux. Actuator) Control Aux. Actuator
[SD1A2718F2H1]
4 Max. Delivery 61 L / min 40 L / min

Set Pressure 7.0 MPa 21.0 MPa

Gear Pump (Drum Cooling) Max. Delivery : 73 L / min 2

5 [SD1A3232F2H1] Set Pressure :
(OPTION)

Motor (Front & Rear Drum) Swash Plate Type, Variable Capacity
8 [M3B800BC] Max. Oil Flow : 252 L / min
Set Pressure : 31.9 MPa
Motor (Boom) Bent Axis Type, Fixed Capacity
10 [A2F250] Max. Oil Flow : 252 L / min
Set Pressure : 32.0 MPa
Motor (Third or Jib) Swash Plate Type, Variable Capacity
11 [M3B800BC] Max. Oil Flow : 252 L / min 6
(OPTION) Set Pressure : 32.0 MPa
Motor (Swing) Swash Plate Type, Fixed Capacity
12 [M2X210] Max. Oil Flow : 175 L / min
Set Pressure : 27.5 MPa
Motor (Propel) Swash Plate Type, Variable Capacity (2-Speed Type)
13 [M3V260] Max. Oil Flow : 252 L / min
Set Pressure : 31.9 MPa
Motor (Tagline) Internal Trochoid Gear Type, Fixed Capacity
14 [2-080AE2-E] Max. Oil Flow : 40 L / min
(OPTION) Set Pressure : 13.7 MPa
Motor (Reeving) Radial Plunger Type, Fixed Capacity
15 [TRCV440] Max. Oil Flow : 40 L / min
(OPTION) Set Pressure : 12.7 MPa
Control Valve (Front & Rear Drum, Max. Oil Flow : 252 L / min
17 Propel) Set Pressure : 31.9 MPa
[MWP225]

Control Valve (Boom) Max. Oil Flow : 252 L / min

18
[MWP125] Set Pressure : 32.0 MPa
Control Valve (Third or Jib) Max. Oil Flow : 252 L / min
19 [MWP125] Set Pressure : 32.0 MPa
(OPTION)

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Item Name of Component Specification

Control Valve (Swing) Max. Oil Flow : 175 L / min
20
[KSC19L] Set Pressure : 27.5 MPa
Control Valve (Gantry & Circuit-change) Max. Oil Flow : 40 L / min
22
[2D04T1S] Set Pressure : 20.6 MPa
Control Valve (Translifter) Max. Oil Flow : 40 L / min
23
[KMC10-6] Set Pressure : 20.6 MPa
Control Valve (Counter-Weight Removal) Max. Oil Flow : 40 L / min
24
[2D04T1S] Set Pressure : 21.0 MPa
Control Valve (Boom Foot Pin & Reeving) Max. Oil Flow : 40 L / min
25 [SC3A-3] Set Pressure : 12.7 MPa
(OPTION)
8-Section Valve 3rd. (Jib) Drum Lower Control Press. Reduce (OPT.)
(Automatic Stop & Speed Adjusting) 3rd. (Jib) Drum Hoist Control Press. Reduce (OPT.)
Fr. Drum Lower Control Press. Reduce
Fr. Drum Hoist Control Press. Reduce
27
Re. Drum Lower Control Press. Reduce
Re. Drum Hoist Control Press. Reduce
Boom Lower Control Press. Reduce
Boom Raise Control Press. Reduce
5-Section Valve Boom Raise Stop (No.2)
(Limit Stop) Boom Lower Stop (No.2)
28 Re. Drum Hoist Stop (No.2)
Fr. Drum Hoist Stop (No.2)
3rd(Jib) Drum Hoist Stop (No.2) [OPT.]
4-Section Valve Fr. Drum Motor Parking Brake
(Motor Negative Brake) Re. Drum Motor Parking Brake
29
Boom Drum Motor Parking Brake
3rd. (Jib) Drum Motor Parking Brake [OPT.]
2-Section Valve Function Lock / Swing Parking Brake
30
Swing Pressure Changeover / Propel Speed Changeover
31 1-Section Valve Swing Reaction

4-Section Valve Re. Drum Clutch On / Off

(Free Fall Changeover) Re. Drum Emergency Stop
33
Fr. Drum Emergency Stop
(OPTION) Fr. Drum Clutch On / Off
3-Section Valve Fr. Drum Free Fall Acceleration
34 (Free Fall Acceleration) Re. Drum Free Fall Acceleration
(OPTION) 3rd. Drum Free Fall Acceleration
37 Port Relief valve

38 Slow Return Check Valve

2-Section Valve 3rd. Drum Clutch On / Off
39 (Free Fall Changeover) 3rd. Drum Emergency Stop
(OPTION)
Pilot Valve 3rd. (Jib) Drum Motor Parking Brake
40 (3rd. Motor Negative Brake)
(OPTION)
Solenoid Valve 3rd. (Jib) Drum Lower Control Press. Reduce
41 (3rd. Automatic Stop & Speed Adjusting) 3rd. (Jib) Drum Hoist Control Press. Reduce
(OPTION)
Solenoid Valve 3rd. (Jib) Drum Hoist Stop (No.2)
42 (3rd. Limit Stop)
(OPTION)
Selector Valve Pedal Remote Control Changeover (boom or Jib)
43 (Pedal Remote Control Changeover)
(OPTION)

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Item Name of Component Specification

Remote Control Valve Fr. Drum
45 Re. Drum
Boom
Remote Control Valve Swing
46
3rd Drum (Jib) [OPT.]
Remote Control Valve Propel
47

Brake Master Valve Foot Brake

48
(OPTION)
Remote Control Valve Boom Control Pedal
49
(OPTION)
Cylinder 150 / 120 750
51
(Translifter) Pressure : 20.6 MPa
Cylinder 160 / 75 1246
52
(Crawler Removal) Pressure : 17 MPa / 20.6 MPa
Cylinder 90 / 45 631
53
(Counter-Weight Removal) Pressure : 21.0 MPa
Cylinder 100 / 50 480
54
(Gantry) Pressure : 20.6 MPa

57 Oil Cooler / Radiator

Swivel Joint 1 Port

58
(Gantry Cylinder) G3/8 (PF 3/8)
Swivel Joint 8 Port
A : Propel (R.H.) Backward B : Propel (L.H.) Backward
59 C : Propel (R.H.) Forward
E : Propel Speed
D : Propel (L.H.) Forward
F : Return (To Tank) 6
G : Aux. Actuator H : Drain
Valve Block Control
60 (Relief Valve & Reducing Valve) Relief Pressure : 7.0 MPa
Reducing Pressure : 5.4 MPa
Relief Valve Tagline
61 (Tagline) Inversely Proportional
(OPTION) Solenoid Operated
Shuttle Valve 2-Section
63
(OPTION) Boom (or Jib) remote control
Slow Return Check Valve Tagline (OPT.)
64
(OPTION) Back Pressure Valve
Slow Return Check Valve Drum Motor Parking Brake Control
65

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Item Name of Component Specification

Suction Strainer 80 Mesh
66
5300 cm2
Return Filter 10 micron (Nominal)
67
38300 cm2
Return Filter 10 micron (Nominal)
68 (Drum Cooling Circuit) 7230 cm2
(OPTION)
Drain Filter 10 micron (Nominal)
69
7230 cm2
Line Filter 149 micron (Nominal) [100 Mesh]
70
(Control) 370 cm2
Line Filter 149 micron (Nominal) [100 Mesh]
71
(Aux. Actuator) 380 cm2
Check Valve Bypass Valve
72
(Return Filter) Bypass Pressure : 0.103 MPa
Check Valve Bypass Valve
73
(Oil Cooler) Bypass Pressure : 0.294 MPa
Check Valve Bypass Valve
74 (Fr. & Re. Drum Cooling Circuit) Bypass Pressure : 0.294 MPa
(OPTION)
Check Valve Bypass Valve
75 (3rd. Drum Cooling Circuit) Bypass Pressure : 0.49 MPa
(OPTION)
Accumulator Gas : N2
76 Gas capacity : 2900 cc
Gas Set Pressure : 3.4 to 3.7 MPa
Flow Control Valve Remote Contorol Circuit
78
(Remote Control)
Pressure Sensor Remote Control Pressure Detect
79

Pressure Sensor Swing Pressure Detect

80

Pressure Sensor Winch Clutch Pressure Detect

81
(OPTION)
Pressure Switch Control Pressure
82
Foot Brake Pressure [OPT.]
Pressure Switch Remote Control Pressure
83 Swing
Propel
Hyd. Oil Temperature Switch 90
84
(For Hyd. Oil Tank)
Hyd. Oil Temperature Switch 130
85 (For Drum Cooling Circuit)
(OPTION)
Check Valve Control Return Line
90
Protect From Back-Pressure-Serge

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Location of Hydraulic Components

The item numbers in figure are linked with the item number in the hydraulic circuit diagrams and "COMPONENT SPECIFICATIONS ".

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HYDRAULIC SYSTEM fixed gear) installed on the power divider mounted directly on
the engine. The two tandem-mounted variable displacement
Preface pumps power the front and rear drums, and the propel
system. The other variable displacement pumps, power the
This section provides a general outline of the overall swing system and the boom drum.
hydraulic system. For more detailed explanations of each
circuit, please refer to the specific sections relating to each The gear pumps directly connected to the tandem plugger
systems. type pumps are provided for control, auxiliary actuator and
drum cooling.
Outline NOTE: The gear pump for drum cooler is optional (with
The pressurized hydraulic oil flowing through these circuits is option for free fall).
supplied by eight pumps (four variable displacement, four

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Oil Flow From No.1 and No.2 Pumps However, when one of the control valve spools is moved by
oil pressure from its remote control valve, then the oil flow
These are tandem mounted, variable capacity pumps. from the pump is directed toward the targeted actuator.
The pressurized oil from the No.1 pump flows through the 2- When the "Inching Speed" switch in the operator's cab is
sectioned control valve for the L. H. propel, front drum used, this activates the inching speed solenoid on the
circuits, while the oil from the No.2 pump flows through the 2- pump's regulator which minimizes the discharge rate of oil
sectioned control valve for R. H. propel, rear drum circuits. In from that pump.
neutral, the flow from each pump passes through its
respective control valve and returns freely to the oil reservoir.

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Oil Flow From No.3 and No.4 Pumps from the No.3 pump powers the swing motor to rotate the
crane's upper body.
This is also a variable capacity pump.
On the other hand, the pressurized oil flow from the No.4
The oil flow from the No.3 pump flows through the control pump flows into the boom control valve, and returns to the
valve for the swing system. tank with no load.
In neutral, the flow from No.3 pump passes through the When the control valve spool is moved by the pressurized oil
control valve and return freely to the oil reservoir. from the remote control valve, the main pressurized oil is led
to the boom motor to actuate the boom.
When the swing valve spool is moved by oil pressure
directed from the swing remote control valve, the oil flow

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Oil Flow From No.5 Pump (Control Pump) valves to the main control valves. Thus operating the
control levers will cause the machine to move.
See the fold-out illustrations on pages 6-21 and 6-22.
Oil Flow From No.6 Pump (Secondary Pump)
The pressurized oil discharged from this fixed capacity gear
pump flows through a line filter, by an accumulator, and See the fold-out illustrations on page 6-23.
through a relief valve that reduces line pressure to 5.4 MPa
The No. 6 pump is fixed capacity gear pump. It is used to the
(782 psi). The pressurized oil is now available to as it flows
gantry cylinder, reeving winch, boom foot pin cylinder,
toward two 4-section valves and two 2-section valves.
counterweight removal cylinder and translifter.
When the Function Lock lever is in the "Shut Down"
The pressurized oil flow from pump No. 6 flows through the
position, the solenoid valve (Sol 3) that is part of the 2-
counterweight removal cylinder control valve. If the
section valve disallows delivery of oil to the remote control counterweight removal control valve, gantry control valve
valves. As there is no control pressure, the machine will and hydraulic selector valve are in its neutral position, the oil
not move even if the its control levers are operated. flow returns freely to the reservoir.
When the Function Lock lever is in the "Operation" Pressurized oil can be supplied to the reeving winch,
position, however, then solenoid valve (Sol 3) allows boom foot pin, or translifter with the hydraulic selector
pressurized oil to be directed from the remote control switch (sol. 45).

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VALVES
4-Section Valve

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8-Section Valve (With Shuttle Valve)

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4-Section Valve

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3-Section Valve

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5-Section Valve

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2-Section Valve

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1-Section Valve

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