Content .. 9 10 11 12 ..

SANY Crawler Hydraulic Excavator SY195C9, SY205C9, SY215C9, SY225C9. Service Manual - page 11

4-79

Structure and Function

Mounting

torque (N·m)

NO.

Part name

Q’ty

Mounting

torque (N·m)

NO.

Part name

Q’ty

101

BLOCK, valve A

308

SPOOL ASS’Y, travel

straight

102

BLOCK, valve B

309

SPOOL, option

13~17

151

PLUG

310

SPOOL, bypass cut

34~39

152

PLUG

311

SPOOL, swing priority

220~250

153

PLUG

320

SPRING

69~78

154

PLUG

321

SPRING

7.4~9.8

156

PLUG, ori

322

SPRING

7.5~10

158

PLUG

323

SPRING

10~14

159

PLUG

326

SPRING

161

O-RING

327

SPRING

162

O-RING

329

SPRING

163

O-RING

331

SPRING SEAT

164

O-RING

332

SPRING SEAT

165

O-RING

16~18

333

FLANGE SOCKET

166

O-RING

335

STOPPER

168

O-RING

16~18

336

FLANGE SOCKET

169

O-RING

337

STOPPER

201

COVER, spring

339

STOPPER

202

COVER, spring

372

SPRING

203

COVER, spring

373

SPRING

204

COVER, spool

511

VALVE, cone

205

COVER, spool

512

VALVE, cone

206

COVER, spool

513

VALVE, cone

209

FLANGE

514

VALVE, cone

210

PLATE

521

SPRING

211

PISTON

522

SPRING

49~65

251

VALVE, logic control

523

SPRING

9.8~14

252

OPTION ASS’Y, lock

valve

541

BALL

254 VALVE GP, swing logic

542

SPRING SEAT

256 VALVE GP, arm 2 logic

543

SPRING

69~78

257

CHECK VALVE ASS’Y,

arm regeneration

25~29

550

PLUG

258

PLUG

230~260

551

PLUG

259

PLUG

230~260

552

PLUG

261

O-RING

130~150

553

PLUG

4-80

Structure and Function

Mounting

torque (N·m)

NO.

Part name

Q’ty

Mounting

torque (N·m)

NO.

Part name

Q’ty

262

O-RING

561

O-RING

264

O-RING

562

O-RING

25~34

273

SCREW, hex, S,H,C

69~78

601

VALVE, main relief

98~120

274

SCREW, hex, S,H,C

69~78

602

VALVE, port relief

301

SPOOL, travel

120~140

604

VALVE, port relief

302

SPOOL ASS’Y, arm 1

69~78

612

PLUG

303 SPOOL ASS’Y, boom 1

49~65

971

SCREW, hex, S,H,C

304

SPOOL, bucket

140~180

975

SCREW, hex, S,H,C

305

SPOOL, swing

977

PLATE name

306

SPOOL, arm 2

978

307

SPOOL, boom 2

4-81

Structure and Function

4.6

Hydraulic System, Part 3

4.6.1

Swing motor

ZX215-1002081

A:  Main oil port
B:  Main oil port
M:  Oil complement port
PA:  Pressure detection port
PB:  Pressure detection port
DB: Lubricating port
PG: Brake release port
SH:  Brake direction port
L:  Oil level stick
IP:  Gear oil feed port

1. Relief valve
2. Reverse prevention valve

For more technical information about the
swing motor, see “Swing motor” on page 3-6.

NOTE: For the location of the swing motor on the machine, see “Hydraulic equipment layout” on
page 4-24.

4-82

Structure and Function

ZX215-1002082

A-A

Spacer

Casing

Disc

Brake

spring

Shell

Check valve spring

Check

valve

Oil distribution plate

Cylinder

10) Brake piston

11) Plate
12) Piston
13) Drive shaft

4-83

Structure and Function

4.6.2

Swing holding brake

●

Port PG is connected with the pilot gear pump directly, and a pressure of 3.9MPa is main-
tained.

ZX215-1002083

Pump

Main valve

●

Otherwise, no pressure is generated at port PX, and port PG is shut off from chamber a be-
neath piston (7). Brake piston (7) is pushed down by brake spring (1). Disc (5) and plate (6)
are pushed together, and the brake is applied.

ZX215-1002084

Pump

Main valve

●

Port SH is connected with port PX of the main valve. Once any movement other than travel
is applied on the main valve, pressure will be generated at port PX, and port PG is intercon-
nected with chamber a beneath piston 7. The pressurized oil compresses brake spring (1)
and pushes the brake piston up. Disc (5) is separated from plate (6), releasing the brake.

4-84

Structure and Function

4.6.3 Relief valve portion

Structure

●

The relief valve portion consists of relief
valves (1) and (2), check valves (3) and (4).

Function

●

When the machine is in the swing holding
mode, control valve (5) closes the motor
outlet circuit, but the motor rotation contin-
ues due to inertial force. The motor output,
therefore, is abnormally increased, result-
ing in motor damage.

●

In order to avoid the motor damage, the
relief valve relieves the abnormally high
pressure to port (M) from the motor outlet
side (high-pressure side) of the motor.

NOTE: For the location of the relief valve on
the swing motor, see “Swing motor” on page 4-81.

4-85

Structure and Function

Operation

1. When swing begins (suppose pressur-

ized oil enters Port A)

●

When the swing control lever is operated
for right swing, pressurized oil from the
pump is supplied to port (A) via control
valve (5).

●

The pressure on port (A) rises, the starting
torque is generated in the motor, and the
motor is activated.

●

The pressurized oil from the outlet port of
the motor passes from port (B) through the
control valve (5) and returns to the tank.

2. When swing stops

●

When the swing control lever is neutral-
ized, the supply of pressurized oil from the
pump to port (A) is cut off.

●

The pressurized oil from the motor outlet
can't return to the tank since the return cir-
cuit to the tank is closed from control valve
(5). Thus, pressure at port (B) rises.

●

Swing resistance is generated on the mo-
tor and hence the brake starts working.

●

Pressurized oil will be relieved when the
pressure on port (B) rises to the set pres-
sure of relief valve (2).

●

A high braking torque is applied on the mo-
tor, thereby stopping the motor.

●

When relief valve (2) is being actuated, the
relieved pressurized oil and the pressur-
ized oil from port (M) are fed to port (B) via
check valve (4).

●

Above prevents cavitation on port (B).

ZX215-1002085

From port M

ZX215-1002086

From port M

4-86

Structure and Function

Valve

body

Spool (A side)

Spring (A side)

Plug

Spool (B side)

Spring (B side)

Plug

4.6.4

Reverse prevention valve

4.6.4.1 Operation drawing

ZX215-1002087

Swing control valve

Swing
motor

NOTE: For the location of the reverse prevention valve on the swing motor, see “Swing motor” on
page 4-81.

4-87

Structure and Function

4.6.4.2 Explanatory drawing of effects

Outline

●

Inertia of the swing body, the backlash and
rigidity of the machinery system, and the
compression of the hydraulic oil all may
cause the machine to shake during swing
operation. The reverse prevention valve is
designed to reduce this effect. The valve
contributes in preventing collapsing of load
when the swing is stopped and also con-
tributes in reducing cycle time (enhances
the positioning performance, enabling you
to proceed to the next work quicker than
ever).

ZX215-1002088

With reversal prevention valve

:Without reversal prevention valve

Reversal pressure

Containment pressure

Time

Start

Brake

Motor speed

Pressure MB

Pressure MA

Reversal pressure

Reversal

1st reversal

2nd reversal

ZX215-1002089

b f

D4 a D3

Notch

4-88

Structure and Function

Operation

1. When port (B) brake pressure is gener-

ated

●

Pressure (MB) is conducted to chamber (d)
via the notch. The pressure compresses
spring (6) by use of the difference in areas
of circles (D1 > D2) of spool (5) and moves
spring (6) to the left side. Port (B) and
chamber (e) will be interconnected. Since
pressure (A) is lower than the set pressure
of spring (3), spool (2) does not move and
the pressurized oil is stopped by spool (2).
Thus the braking force is ensured.

2. When motor is stopped

●

The motor rotation is reversed by the clos-
ing pressure generated at port (B). (1st
time: reverse rotation) Reversing pressure
is generated on port (A). Pressure (A) is
conducted to chamber (a), and spool (2)
moves spring (3) to the right side, and A
and B is interconnected. At this time, b
is interconnected with f via the orifice on
spool (5), and reversing pressure on port A
is bypassed to port T, preventing the sec-
ond reverse rotation.

ZX215-1002090

E I

' D '

Notch

ZX215-1002091

4-89

Structure and Function

ZX215-1002092

H-H

Swing

shaft

Dust

seal

O-ring

Swing

body

Rotating

seal

100x5

Gasket

Retaining

ring

Plug

(ZG3/4)

Plug

(ZG1/4)

10) Cover
11) Spacer
12) Gasket
13) Gasket

4.6.5 Center swivel joint

NOTE: For the location of the central swivel joint on the machine, see “Hydraulic equipment lay-
out” on page 4-24.

4-90

Structure and Function

From main valve BTL

From main valve BTR

From main valve ATL

From main valve ATR

A1:

To L. travel motor port (P1)

B2:

To R. travel motor port (P2)

C3:

To L. travel motor port (P2)

D4:

To R. travel motor port (P1)

To swing motor port DB

G1:

From travel motor

nal drive assembly oil drain port (D1,D2)

From solenoid valve port A2

F1:

To travel motor reducer Hi/Lo speed switching port (P)

4-91

Structure and Function

4.6.6 Travel motor

Model: TM40VD-A-99/163-1

WX215-1204014G

Ps:    Duo speed pilot hose port
P1:    Pressure detection port
P2:    Pressure detection port
P5:    Parking brake release port

D1: Drain port
D2: Plug
A:

Main oil port

Working condition

Speed 1

Speed 2

Reduction gear

Gear ratio

49.95

Theoretical output torque

(kgf.m)

Max. 4650

4535

2767

Theoretical output speed

(r.p.m)

Max. 60

45.9

Hydraulic motor

Displacement

(cc/rev)

Max. 174.7

162.9

99.4

Continuous pressure

(kgf/cm2)

Max. 350

350

Theoretical speed

(r.p.m)

Max. 2800

1400

2294

Flow

(l/min)

250

228

Duo speed control pressure

(kgf/cm2)

20~70

Braking torque

(kgf.m)

Min. 50

Brake release pressure

(kgf/cm2)

8.2

Relief valve activation pressure

1~3L/min (above 365)

15L/min (above 420)

NOTE: For the location of the travel motor on the machine, see “Hydraulic equipment layout” on
page 4-24.

4-92

Structure and Function

Explosive view

Flange,

rear

H5 balance valve

spool
3)

Plug

D type block

Check

plug

Check

valve

Spring

Stop

spring

O-ring

10) O-ring
11) Parallel pin
12) Socket head bolt
13) O-ring
14) Plug
15) Plug

16) Plug
17) Spool
18) Spring
19) Ball
20) Ori

21) O-ring
22) Filter
23) Name plate
24) Rivet
25) Plug
26) Drive shaft
27) P - t y p e s w a s h
plate
28) Cylinder block
29) Piston
30) Stopper

31) Baf

32) Spheric bush
33) Timing plate
34) Parking piston
35) Spring
36) Cylinder block
spring
37) Friction plate
38) Spacer
39) Oil seal
40) O-ring
41) O-ring
42) Parallel pin
43) Washer
44) Washer
45) Ball bearing

46) Ball bearing
47) Spring
48) Piston
49) Stopper
50) Pivot
51) Plunger
52) Piston seal
53) Valve body
54) Washer
55) O-ring
56) O-ring
57) Shim
58) Spring
59) Piston rod

23 24

WX215-1204013G

4-93

Structure and Function

Ps:    Duo speed pilot hose port
Pm1:  Pressure detection port
Pm2:  Pressure detection port
Tin:    Motor case inner oil port
Pp:    Brake release port
Dr:    Oil drain port
P1:    Main oil port
P2:    Main oil port

A. Mounting surface with sprocket
B. Mounting surface with undercarriage
1. Mounting hole with sprocket
2. Mounting hole with undercarriage

ZX215-1002132

Tin

Pm1

Pm2

NOTE: For the location of the travel motor on the machine, see “Hydraulic equipment layout” on
page 4-24.

NOTE: For more technical information about the travel motor, see “Travel motor” on page 3-7.

Model: MAG-170VP-3400E

4-94

Structure and Function

ZX215-1002093

2-4

2-3

2-2

2-6

2-5

1-5

1-6

1-2

1-1

2-1

1-4

1-3

Connected to sprocket

Mounted on the undercarriage

Piston motor shaft

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