Shantui SD22. Operation and Maintenance Manual

DOZING OPERATION | OPERATION

Adjustment of straight tilt blade

1. Adjustment of straight tilt blade’s tilt

• Simply operate blade control lever to let the blade tilt

425mm. If necessary, changing the left support arm’s

length L (Figure 2-80) can further tilt it to 500mm. The sup-

port rod’s length L is generally 1287mm, and the blade’s tilt

should be within 500mm. Do not attempt to tilt the blade to

more than 500mm, to prevent unwanted effect.

Figure 2-80

2. Adjustment of gaskets

• Adjust the thickness of the gaskets, to let the clearance of

the spherical joint in the axle direction be not over 1mm

(Figure 2-81, the position pointed by arrow).

• Remove gasket (1), and tighten bolt (2), to eliminate the

spherical joint’s clearance. (Figure 2-82) Measure the clear-

ance A, and remove bolt (2). Put in a gasket with a thick-

ness of A+1mm (1), and tighten bolt (2). Confirm if after the

bolt is tightened the spherical joint can flexibly rotate.

Figure 2-81

OPERATION | DOZING OPERATION

2.5.3 DOZING OPERATION

Cutting of hard earth or frozen earth (Figure 2-83)

When operating on hard earth or frozen earth, using straight

tilt blade or angle blade can effectively dig; if the earth is very

hard, using ripper can increase efficiency.

Figure 2-83

2.5.4 LEVELING OPERATION (FIGURE 2-84)

The uneven ground after excavating dozing can be leveled

using the following methods:

• Fill the blade with soil, let the vehicle run at a low speed,

and level the uneven areas when moving.

• Put the blade in the “floating” state, move the vehicle slowly

backward to smooth the ground.

Figure 2-84

Smoothing cannot be used on rocks, as it can damage

the blade.

2.5.5 DOZING SIDEWAYS

When dosing sideways, use the angle blade. (Figure 2-85)

CAUTION

• Do not use the blade to dig tree root etc.

• During dozing and moving, avoid sudden start, sudden

brake and sudden turn if possible.

Figure 2-85

DOZING OPERATION | OPERATION

2.5.6 METHODS FOR EXTENDING MACHINE LIFE

The life of the vehicle, especially the walking parts, is de-

pendent on the maintenance and operation methods to a

big extent. Therefore, remember the following points:

1. Select different models with different types of tracks ac-

cording to soil type.

2. During operation, reduce track slip as far as possible. If

the track slips, reduce the load until it no longer slips.

Figure 2-86

3. Avoid sudden start, sudden acceleration, unnecessary

high-speed operation, as well as sudden brake or sudden

turn if possible.

4. Always operate the vehicle to travel in a straight line as

far as possible. Do not always turn to one side. Turn to left

and right alternately and at the biggest radius.

5. During dozing, if the terrain forms a gentle slope to left or

right, reverse the vehicle to the level ground and level it

again. Do not continue to operate on the slope.

6. Do not let the vehicle try to handle a hard object or an ob-

stacle that is hard to handle, or the idler or Sprocket will

leave the ground. (Figure 2-86)

7. When operating on an inner slope, the vehicle should trav-

el along the slope from top to bottom, and should not cross

the slope. When travelling uphill, do not back. (Figure 2-87)

Figure 2-87

• Before operation, clear the big rocks and other obstacles

from the jobsite.

OPERATION | TOWING, LIFTING, TRANSP. & STORAGE

2.6 TOWING, LIFTING, TRANSPORTATION AND STORAGE

2.6.1 TOWING (FIGURE 2-88)

Towing is the operation to draw the bulldozer using the front

and rear towing devices for darwing or self-rescue.

►►

When using front and rear towing devices for drawing or

self-rescue, ensure that the towwing cables and the towing de-

vices can be reliably connected and locked, and that the tow-

Front towing bracket

ing cables can safely carry the towing load.

CAUTION

The effective safe load of the bulldozer’s front and rear

towing devices is 15tons.

Rear traction frame

Figure 2-88

2.6.2 LIFTING (FIGURE 2-89)

When the bulldozer is lifting, operate in the way shown in the

The craning positions of the

figure below.

entire bulldozer

►►

During lifting, ensure that the lift rope can be reliably

locked, and avoid the direct contact between the weight-bear-

ing point and the bulldozer’s edge (put a block beneath the

corner of the track). (Bulldozer’s dead weight: 23.4tons)

Craning position

1. The craning positions of the vehicle

are shown in the figure.

2. Prior to craning, shut down the en-

gine, and put the entire vehicle in

CAUTION

the parked, braked and locked state.

09963- 02100

During lifting, ensure that the bulldozer is locked. (Step

Figure 2-89

down the brake pedal, and raise the brake lock lever)

TOWING, LIFTING, TRANSP. & STORAGE | OPERATION

2.6.3 TRANSPORTATION

During the vehicle transportation process, be familiar with and

abide by various road rules as well as the traffic rules including

the rules about the transportation of vehicles on the road and

the restrictions on vehicles. When going through bridges and

tunnels, measure the allowed weight of the bridges and the

space sizes of the tunnels.

It’s best to create a special loading/unloading platform. If using

a ramp to load the machine to a trailer, follow the rules below.

(Figure 2-90)

CAUTION

Figure 2-90

When traveling up a ramp, do not adjust the travel direc-

tion. If you need to adjust the direction, back the vehicle

to the ground and make the adjustment.

The brake of the trailer should be applied, and the wheels

are secured with blocks.

Make sure the ramp has sufficient width, length and thick-

ness to enable the machine to be safely loaded and un-

loaded.

Make the ramp properly aligned, and then slowly load/

download the machine.

The vehicle should be put in the trailer’s appropriate posi-

tion, insert blocks beneath the track in front and back, and

then use solid and firm chains or ropes to secure it, to pre-

vent it from falling off during the transportation process to

cause accidents.

Lower the blade, and put various levers to the following

positions.

•

Put the throttle control lever in the low-speed position, and

remove the starting key.

•

Put the gear shift lever in the NEUTRAL position.

•

Put the blade control lever in the KEEPING position.

•

Put the brake lock lever in the LOCK position.

CAUTION

•

If the blade head’s width is wider than the trailer’s

width, you can change the blade’s angle or unload it

and load it again.

•

For long-distance water transportation, take anti-rust

measures, and apply anti-rust oil to the exposed oil cyl-

inder’s piston rod etc.

OPERATION | TOWING, LIFTING, TRANSP. & STORAGE

2.6.4 STORAGE

Before storage

When you expect the machine will be stored for a significantly long period of time, be sure to take

the following measures, to reduce the repair work when using the machine again.

1. After cleaning each part of the machine, store the machine in a dry building. If the machine has

to be put outdoors due to limited conditions, put wood planks on the ground, put the machine on

the wood planks, and cover the machine with canvas.

2. Before putting into garage, add sufficient fuel and lubricant, and change new engine oil.

3. Apply a layer of lubricant on metal surface. (At the piston rod)

4. Remove the terminals of the battery, cover them properly or store them separately.

5. If you expect the ambient temperature can be lowered to below 0°C, add antifreeze to the cool-

ing water beforehand.

6. Set various control levers and pedals as follows:

►►

Put the gear shift lever to the NEUTRAL position.

►►

Put the throttle control lever to the LOW SPEED position.

►►

Put the blade control lever to the KEEPING position.

►►

Put the brake pedal to the FREE position.

During storage

Start the engine once a month, and operate the vehicle for a distance. This is in order to let the ma-

chine’s parts and the surface of the engine’s various areas have a new layer of oil membrane.

►►

When operating the work parts, wipe off the lubricant grease on the hydraulic piston rod.

After storage

After storage (if not covered or not performing the anti-rust operation once a month), you must do

the following before use:

1. Remove the engine oil pan and other drain plugs of the oil tank, to drain the mixed water.

2. Remove the cylinder cap, lubricate various air throttles and rock arms, and check the action of

air throttles.

3. In order to exhaust hydraulic system’s air, run the engine at a low speed, and operate as follows:

• Operate each hydraulic cylinder back and forth 4-5 times, and let the piston stop at a place

100mm from the end of its journey.

• Continue to operate each hydraulic cylinder back and forth 3-4 times to the end of its journey.

►►

If the engine runs at a high speed at the beginning or if the piston runs to the end of its journey,

then the air getting into it may damage piston disc.

4. After the engine is started, let it run, until the temperature reaches the required value.

MACHINE STRUCT. & MAIN PARAMETERS | STRUCTURE & PRINCIPLE

3.1.2 SPECIFICATIONS AND TECHNICAL PARAMETERS

Engine

Model

Cummins NT855-C280(BC III)

Weichai WD12

Inline, water-cooled, four-stroke, top-valve direct injection, and turbo

Type

diesel engine

Rate speed

1800rpm

Rate power

162kw (220HP)

175kW

Cylinder number-cylinder

6-139.7mmX152.4mm

6-126mmX155mm

diameter ×stroke

Piston displacement

14.01 L

11.596 L

Minimum fuel consumption

≤205g/kw.h(153g/ps.h)

208g/kW.h

Suitable altitude

Below 3000m

Travel speed (km/h)

Gear I

Gear II

Gear III

Forward

0~3.6

0~6.5

0~11.2

Reverse

0~4.3

0~7.7

0~13.2

Track performance curve

Lever’s traction and travel speed

Travel speed

Figure 3-2: Track performance curve

STRUCTURE & PRINCIPLE | MACHINE STRUCT. & MAIN PARAMETERS

Characteristics of the drive system

1. The hydraulic torque converter: three assemblies, single-level and single-phase.

2. Transmission case: planetary gear, multi-piece clutch, hydraulic, and forced lubrication.

3. Central drive: spiral bevel gear, primary reduction, and splash lubrication.

4. Steering clutch: wet, multi-spring pressed, hydraulic detach, and manual-hydraulic operation.

5. Steering brake: wet, floating band, and hydraulically assisted.

6. Final drive: two-stage straight gear reduction, and splash lubrication.

Walking system

Type:

Swing type of sprayed beam, suspended structure of equalizer bar

Number of carrier roller

2/each side

Number of track rollers:

SD22: 6/each side (four for one-sided and two for two-sided)

SD22E: 7/each side (four for one-sided and three for two-sided)

Track type:

SD22S: 8/each side (five for one-sided and three for two-sided)

SD22: Assembled single-track tooth (38 pieces each side)

Track shoe width:

SD22E: Assembled single-track tooth (41 pieces each side)

SD22S: Assembled arched triangle tooth (45 pieces each side)

SD22 and SD22E:

560mm (Straight tilt blade, angle blade)

610mm (U-Blade)

Track pitch:

SD22D:

610mm

SD22S:

910mm

216mm

MACHINE STRUCT. & MAIN PARAMETERS | STRUCTURE & PRINCIPLE

Dozing devices

SD22 and SD22E

SD22S

SD22D

Model

Parameter

Straight

Angle

U-Blade

Straight tilt blade

tilt blade

blade

Blade width (mm)

3725

4365

3800

4365

Blade height (mm)

1315

1055

1343

1248

Maximum Cutting Depth (mm)

540

535

540

550

Maximum lift height (mm)

1210

1290

1210

1330

1420

Blade-maximum tilt (mm)

>735

>500

>755

>500

>800

Maximum blade angle

(°)

Cutting angle (°)

Mass (Kg)

3630

3850

4196

3478

2900

Ripper

Type:

Parallelogram adjustable and removable

Number of gear teeth:

1-3 teeth

Pitch:

1000mm (Three teeth)

2000mm (Two teeth)

Maximum ripping depth:

665 mm

Maximum lift height:

555 mm

Mass:

2900 Kg

Hydraulic system (work equipment)

Maximum operating oil pressure: 14Mpa(140kg/cm²)

Oil pump type: gear oil pump

Flow: 262L/min (engine speed 1800rpm)

Control value type: Lubricating valve

Tilt cylinder’s inner diameter×quantity: Φ120mm×2 (dual-acting)

Tilt cylinder’s inner diameter×quantity: Φ200mm×1

Ripping oil cylinder’s inner diameter×quantity: Φ150mm×1

Ripper’s safety valve pressure: 16Mpa(160kg/cm²)

STRUCTURE & PRINCIPLE | MACHINE STRUCT. & MAIN PARAMETERS

Dimensions (Unit: mm)

Figure 3-3

Unit: mm

Model

SD22

SD22E

SD22S

SD22D

Dimensions (Unit: mm)

5750

6000

6060

6150

3725

4365

Do not install the driver’s cab

3395

3435

Install the 23Y-56B-00000 cab

3402

3807

L₁

3725

3850

3806

L₂

2730

3050

3480

3050

L₃

1155

1405

1595

1405

W₁

560

910

660

W₂

2000

2250

2000

W₃

2620

3160

2660

H₁

2610

2645

2610

H₂

470

805

470

H₃

540

550

H₄

1210

1416

1330

1420

H₅

735

500

800

H₆

123

Note: When H>3395. H is the distance from the top surface of the cab installed to the ground. For

SD22D, H is the height of the air cleaner’s cap from the ground.

MACHINE STRUCT. & MAIN PARAMETERS | STRUCTURE & PRINCIPLE

Other performance parameters

SD22 and SD22E

Model

SD22S

SD22D

Parameter

Straight

Angle

U-Blade

tilt blade

blade

Minimum ground clearance (mm)

405

513

405

19800

Tractor

22250

(21000)

Operating weight (kg)

23450

23670

24020

Bulldozer

25700

28000

(24600)

(24800)

(25200)

0.065

0.059

Tractor

0.034

(0.061)

Contact pressure (Mpa)

0.077

0.078

Bulldozer

0.041

0.070

(0.072)

(0.073)

3300

Minimum turning radius (mm)

3800

4100

(4000)

Slope climbing performance

Caterpillar’s central distance (mm)

2000

2250

2000

Single blade capacity (m³)

5.6

4.2

6.2

5.9

Productivity (m³/h)

330

245

365

345

Note: Operating weight and contact pressure do not include the weight of the cab and the ripper.

Productivity refers to the theoretic value for transporting 40 meters.

The parameter values within the parentheses are the corresponding parameter values of SD22E

ENGINE | STRUCTURE & PRINCIPLE

3.2.2 ENGINE’S MAIN PERFORMANCE INDICATORS

Main performance parameters

Engine Model

NT855-C280(BC III)

WD12

Number of cylinders-cylinder

6—139.7×152.4

6—126×155

diameter × stroke (mm)

Total replacement (L)

14.01

11.596

Ignition sequence

1-5-3-6-2-4

1691

1478.9

Overall length (mm)

(Flywheel housing ~ fan’s

(Flywheel-Fan pulley’s front

front end)

end)

1116

1110

Overall width (mm)

(Rear bracket~Rear bracket)

2741.9

2015.5

Overall height (mm)

(Exhaust pipe~Oil pan’s

(Pre-filter~Oil pan’s purge

purge valve)

valve)

Net weight(kg)

1750

1150

Rate speed (rpm)

1800

Rate power (kw)

162(220PS)

175

Maximum torque (N•m/

1030/1250

1120

rpm)

Highest speed without

1950±50

1940+40

load (rpm)

Lowest speed without load

600±50

750±50

(rpm)

Minimum fuel consumption rate

≤205

208

(g/kw•h)

Silicon rectified generator

Charging engine

24V35A

24V55A

Starting form

Starting motor 24V11KW

Starting motor 24V6.6KW

Battery

24V195A-h×2

Engine oil pan capacity (L)

Cooling water capacity (L)

20.8

Description of engine’s various systems

See engine’s User Manual for details.

ENGINE | STRUCTURE & PRINCIPLE

2. TRANSFER CASE (FIGURE 3-8)

Figure 3-8

No.

Name

No.

Name

No.

Name

Flywheel housing

Main shaft

Lubrication tube

Transfer case body

Driving wheel

Distributer

Driven wheel

Cover

Transfer case cover

Driven wheel

Transfer case is installed in the upper part of the flywheel’s housing. The gear in the upper part of

the flywheel’s housing drives the main axle (5) and the driving wheel (6) to rotate, thus making the

driven wheels (3) and (8) rotate. Remove cover (7) to install the working oil pump. Driven wheel (3)

drives the transmission pump. Install the steering pump on the front side of the flywheel’s housing.

The lubricating oil of the transfer case’s gear and bearing comes from the oil cooler’s oil returning

hose, to be distributed by the distributor (10), and drop to various related parts via the lubricating

pipe (9).

STRUCTURE & PRINCIPLE | ENGINE

3.2.4 RADIATOR ASSEMBLY (SEE FIGURE 3-9)

Radiator mainly consists of upper box (1), radiator (12), lower box (10) and related attachments.

The cooling water flows through thermostat to enter upper box (1), removes air from water, and then

flows through the radiator core (12) to enter lower box (10). When the cooling water flows through

the radiator core (12), due to the role of the fan in the back end of the radiator, the water in the core

is cooled. The cooled cooling water is pumped out from lower box by water pump to the engine’s

cylinders.

This radiation system is a closed system. The pressure valve installed on the water tank maintains

water tank pressure within a range 0.075MPa lower than the gauge pressure, so as to increase the

evaporation temperature of the cooling water, to reduce water loss, and to increase cooling efficien-

cy.

The fan’s (13) power is transmitted by the V-shaped belt wheel on the front of the engine. The forced

air from the fan can enhance the cooling effect.

The SD22D bulldozer’s fan pulley (6) is designed to have two specifications. Small pulley is used in

summer, and big pulley is used instead in winter when the engine is too cold.

STRUCTURE & PRINCIPLE | ENGINE

3.2.5 FUEL TANK AND PIPING (SEE FIGURE 3-10)

The fuel tank is installed in the back part of the vehicle. Fuel is injected into the fuel tank through the

filter screen. Removing the entrance’s cap, you can find the dipstick. Fuel flows from the fuel tank

into the fuel injection pump’s fuel filter The fuel tank has a fuel stop valve and an oil drain valve on

the back.

Guard plate’s

upper plane

Fuel filter

To Fuel pump

Crankshaft's

Center

Cross shaft’s

center

Vehicle body

center

Center of the

operator’s seat

Center of the

fuel tank

Figure 3-10

STRUCTURE & PRINCIPLE | ENGINE

3.2.7 HYDRAULIC TORQUE CONVERTER (FIGURE 3-12)

Figure 3-12

No.

Name

No.

Name

No.

Name

Driving gear

Cover

Driving gear

Drive shell

Shaft coupling

Coarse strainer

Turbine

Turbine output shaft

Discharge outlet

Torque converter hous-

Guide roller axle's hub

Turbine hub

ing

Pump impeller

Guide roller

Binder plate

Driving gear

Fuel pump housing

Guider

Guide roller’s axle

Driving gear

ENGINE | STRUCTURE & PRINCIPLE

This machine uses the three-component one-stage and one-phase hydraulic torque converter.

The pump impeller (5), turbine wheel (3) and guide roller (12) are full of the operating oil. When the

pump impeller (5) rotates, the pump impeller will force the oil to impact the turbine wheel’s blade, so

as to make the turbine wheel rotate. The oil flows from the turbine wheel into the guide roller, and

flows out of the guide roller, to enter the pump impeller’s intake and complete the cycling process of

the oil.

The guide roller can change the rotation movement of the liquid, so it make increase the turbine

wheel’s torque. But the turbine wheel’s torque changes with the operating conditions. Therefore,

when load increases, the turbine wheel will bear a higher resisting torque, so as to automatically

reduce speed. Therefore, the hydraulic torque converter can ensure the smooth operation of the ma-

chine.

The power input route is: Driving gear (1) → Drive shell (2) → Pump impeller (2).

The power output route is: Turbine wheel (3) → Turbine hub (17) → Turbine wheel’s output shaft (10).

STRUCTURE & PRINCIPLE | UNIVERSAL JOINT

3.3 UNIVERSAL JOINT (FIGURE 3-13)

The role of the universal joint is to transmit the power between the hydraulic torque converter and

the transmission case. It can ensure that when the coaxiality of the turbine wheel’s output shaft

and the center line of the transmission case’s main is within the allowed range, the power can be

smoothly transmitted.

Figure 3-13

No.

Name

No.

Name

Cross shaft coupling assembly

Connecting plate

Bolt

TRANSMISSION CASE | STRUCTURE & PRINCIPLE

3.4 TRANSMISSION CASE (FIGURE 3-14)

The role of the transmission case is:

1. To realize the machine’s FORWARD and REVERSE.

2. To get different transmission ratios (including stopping).

• This machine uses the planetary gear multi-disc clutch structure. Relying on hydraulic force and

operated by the control valve, it can provide three forward gears and three reverse gears.

• No.1 Clutch is FORWARD, No.2 is REVERSE, No.3 is the third gear, No.4 is the second gear,

and No.5 is the first gear.

Figure 3-14

STRUCTURE & PRINCIPLE | TRANSMISSION CASE

No.

Name

No.

Name

Transmission case housing

Input shaft

The first clutch’s oil cylinder body

Bearing support

The first clutch’s piston

Cover

The brake’s driving disc

Bearing Cover

Friction disk

Bearings’ guard plate

Plate

The fifth clutch’s piston

The first, the second and the third

The fifth clutch’s inner hub

rows of planetary pinion’s axis

The second clutch’s piston

The fourth planetary row's spring

The second clutch’s oil cylinder body

Butterfly-shaped spring

The third and the fourth clutchs' oil

The fourth row of carrier

cylinder body

The third clutch’s piston

The third planetary row's spring

The fourth clutch’s piston

The second planetary row's spring

Plate

The first planetary row's spring

The fourth row of planetary pinion’s

The first, the second and the third

axis

rows of carrier

The fifth clutch’s outer hub

Bolt

The second row of planetary pinion’s

The fifth clutch’s oil cylinder body

axis

Check valve’s steel ball

Bearing support

Box body (Rear)

Bearing support

Housing body

Retainer

Out sleeve

Shaft coupling

Gear position

Working clutch

Gear 1

No.1, No.5

FORWARD

Gear 2

No.1, No.4

Gear 3

No.1, No.3

Gear 1

No.2, No.5

REVERSE

Gear 2

No.2, No.4

Gear 3

No.2, No.3

TRANSMISSION CASE | STRUCTURE & PRINCIPLE

3.4.1 PLANETARY GEAR MECHANISM’S PRINCIPLE AND CLUTCH MECHANISM

Planetary gear’s operating principle (See figure 3-15)

The planetary gear mechanism shown in the figure is con-

sisted of sun wheel (A), planetary pinion (B), gear rim (C), and

carrier (D). planetary pinion (B) is installed on carrier (D). It

also engages with sun wheel (A) and gear rim (C) at the same

time.

Clutch

No.

Name

No.

Name

Sun wheel

Planetary pinion

Gear ring

Carrier

Figure 3-15

1. If the gear rim is fixed, the motion is transmitted from sun

wheel (A) to planetary pinion (B). In this case, planetary

pinion (B) rotates on its own on the one hand, and its axis

also revolves around sun wheel (A). In the structure shown

in the figure, the revolution direction of the planetary pin-

ion’s axis is the same as that of sun wheel (A). (See Figure

3-16) (See Figure 3-16)

Figure 3-16

2. If carrier (D) is fixed, the motion is transmitted from sun

wheel (A) to planetary pinion (B), and is again transmitted

by (B) to gear rim (C), to make gear rim (C) rotate. In the

structure shown in the figure, the rotation direction of gear

rim (C) is opposite to that of sun wheel (A). (See Figure

3-17) (See Figure 3-17)

Figure 3-17

100

STRUCTURE & PRINCIPLE | TRANSMISSION CASE

The above principle is the structural principle of the first, third,

and fourth rows of the planetary gear mechanism.

In the first row of the planetary gear mechanism, sun wheel (A)

is the driving part. In the third and the fourth rows of the plan-

etary gear mechanism, carrier (D) is the driving part.

To obtain an output rotation direction opposite to that de-

scribed above, you just need to add a group of planetary gear

(E) (see Figure 3-18). The (A)→(B)→(E)→(C) motion trans-

mission form is the structural principle of the second row of the

planetary gear mechanism.

Figure 3-18

No.

Name

No.

Name

Sun wheel

B, E

Planetary pinion

Gear ring

Carrier

Various clutch mechanisms (see Figure 3-28)

The transmission case’s fifth row of clutch is a lock clutch.

Figure 3-19

101

TRANSMISSION CASE | STRUCTURE & PRINCIPLE

The fixing method for each row of the planetary gear rim is

shown in Figure 3-29. It is realized through clutch.

Figure 3-20

The engagement of clutch is realized by driving piston (3)

through the pressure from the control valve. (See Figure 3-21)

(See Figure 3-21)

Figure 3-21

The disengagement of clutch is realized by pushing piston (3)

to its original place through reset spring (33) after the pres-

sure oil is cut off (see Figure 3-22). (42) is the butterfly-shaped

spring. Its role is to accelerate the returning speed of piston (3),

to improve the separation effect of the driving and driven fric-

tion disks.

Figure 3-22

102

STRUCTURE & PRINCIPLE | TRANSMISSION CASE

Figure 3-23 is the structural scheme of the fifth row of clutch.

When this clutch is disengaged, the working oil in the back

space of oil cylinder (16) is under the action of the centrifugal

force generated through rotation, and therefore relying on the

butterfly-shaped spring (29) alone can’t ensure the rapid sepa-

ration of the friction disks. This will put the clutch in a semi-

disengaged state, and a fault may occur when you change

the gear next time. In order to eliminate this phenomenon, the

steel ball check valve (17) is put inside.

Figure 3-23

When the fifth row of clutch is engaged (see Figure 3-24), the

pressure oil from the control valve enters the oil chamber to

push piston (26). Meanwhile, the pressure oil also pushes the

check valve’s steel ball (17), to block the valve seat’s orifice,

so that the clutch is rapidly engaged.

Figure 3-24

When the pressure oil from the control valve is cut off, due

to the centrifugal force, the steel ball (17) moves toward the

direction indicated by the arrow in Figure 3-25. In this case,

the valve seat’s orifice is opened, and the working oil in the

back space of oil cylinder (16) is drained out through the valve

seat’s orifice, to ensure the normal separation of the friction

disks.

Figure 3-25

103

TRANSMISSION CASE| STRUCTURE & PRINCIPLE

3.4.2 THE POWER TRANSMISSION ROUTE OF THE VARIOUS GEARS OF THE TRANSMIS-

SION CASE

Transmission route of the first gear FORWARD (See Figure 3-26)

In this case, the first and the fifth clutches are engaged at the same time.

The power transmission sequence is: A→B→(34)→J→O→P→Q (Clutches J, N, H, K, and L are

combined into one)

Gear 3

Gear 2

Gear 1

The output shaft

slides onto the

input shaft

Figure 3-26

Transmission route of the second gear FORWARD (See Figure 3-27)

At this point, the first and the fourth clutches are in the engaged state, and the first and the fourth

gear rims are fixed.

The power transmission route is: A→B→(34)→J→(30)→L→K→O→P→Q

Gear 3

Gear 2

Gear 1

The output shaft

slides onto the

input shaft

Figure 3-27

104

STRUCTURE & PRINCIPLE | TRANSMISSION CASE

Transmission route of the third gear FORWARD (See Figure 3-28)

At this point, the first and the third clutches are in the engaged state at the same time.

The power transmission route is: A→B→(34)→J→I→H→O→P→Q

Gear 3

Gear 2

Gear 1

The output shaft

slides onto the

input shaft

Figure 3-28

Transmission route of the first gear REVERSE (See Figure 3-29)

At this point, the second and the fifth clutches are in the engaged state at the same time.

The power transmission sequence is: D→E→F→(34)→I→J→O→P→Q (Clutches J and K are com-

bined into one)

Gear 3

Gear 2

Gear 1

The output shaft

slides onto the

input shaft

Figure 3-29

The transmission route of the second gear REVERSE and the third gear REVERSE is omitted.

As long as the second and the fourth clutches can be engaged at the same time, you can get the

second gear REVERSE. And as long as the second and the third clutches can be engaged at the

same time, you can get the third gear REVERSE.

105

CENTRAL DRIVE | STRUCTURE & PRINCIPLE

3.5 CENTRAL DRIVE (SEE FIGURE 3-30)

The main role of the Central drive is: 1. To change the power transmission direction (to change from

longitudinal to horizontal). 2. To apply primary reduction, to increase torque. The Central drive, the

steering clutch and the steering brake are all installed in the cavity of the steering case.

Figure 3-30

No.

Name

No.

Name

No.

Name

Outer hub

Hub

Big spring

Platen

Bearing support

Small spring

Outer friction disk

Big bevel gear

Bolt

Inner tooth

Cross shaft

Inner drum

Adjusting gasket

106

STRUCTURE & PRINCIPLE | CENTRAL DRIVE

The central drive consists of the big bevel gear (8) (engaged with the transmission case’s output

gear), the cross shaft (9), the bearing support (7), and the bearings. The correct engagement of a

pair of bevel gears can be achieved by adjusting the adjusting gasket (10) as well as the adjusting

gasket between the transmission case’s small bevel gear assembly and the housing. You can judge

it by checking the tooth side’s clearance and the engagement impression.

The standard clearance of a pair of the spiral bevel gears is 0.25~0.33mm. The engagement impres-

sion along the tooth length direction should not be smaller than half of the tooth’s length, and should

be closer to the smaller end along the tooth length direction (30% more on the smaller end). The

height should be half of the tooth’s height. See Figure 3-31.

Figure 3-31

107

CENTRAL DRIVE | STRUCTURE & PRINCIPLE

If the engagement is not normal, make adjustment using the methods in the table below.

Position of the contact impression

Gear moving

Adjustment method

on the passive tooth surface

direction

Move the driven gear toward the driv-

ing gear. If this makes the clearance too

small, move the driving gear outward.

FORWARD

Move the driven gear away from the driv-

ing gear. If this makes the clearance too

big, move the driving gear inward.

Move the driving gear toward the driven

gear. If this makes the clearance too

small, move the driving gear outward.

REVERSE

Move the driving gear away from the

driven gear. If this makes the clearance

too big, move the driving gear inward.

Move the driving gear toward the driven

gear. If this makes the clearance too

small, move the driving gear outward.

FORWARD

Move the driving gear away from the

driven gear. If this makes the clearance

too big, move the driving gear inward.

Move the driven gear away from the driv-

ing gear. If this makes the clearance too

big, move the driving gear inward.

REVERSE

Move the driven gear toward the driv-

ing gear. If this makes the clearance too

small, move the driving gear outward.

108

STRUCTURE & PRINCIPLE | STEERING CLUTCH

3.6 STEERING CLUTCH

The steering clutches are located in the left & right chambers

of the steering case, with one on each side. Their role is to

connect or cut off the power from the central drive to the final

drive, to realize various actions including the entire vehicle’s

forward, reverse, turn, and stop.

Steering clutch’s structure mainly consists of the inner & outer

drums, the platen, the inner & outer friction disks, and the

Figure 3-32

spring.

This machine adopts a wet, multi-piece, spring-pressed, hy-

draulically-detached long-engagement structure.

Normally, due to the spring, the inner & outer friction disks are

connected, and the power from the cross shaft is transmitted

to the final drive disc through wheel (6)→inner drum (5)→inner

tooth (4)→outer friction disk (3)→outer drum (1).

When the steering lever is pulled, the pressure oil from the

steering control valve enters the inner cavity of the inner drum

(6) (See Figure 3-32) to push the piston (10), bolt and platen

(2) to move to the arrow direction (Overcome the pressure of

the big and small springs), so as to disengage the friction con-

nection between the inner tooth (4) and the outer friction disk

(3), to stop the outer drum (1) from rotating, so as to cut off the

power transmission.

When the steering lever is released, the oil pressure is cut off,

and due to the pressure of the big & small springs, the above

parts are forced to move in the direction indicated in the fig-

ure, to enable the inner tooth (4) and the outer friction disk to

become engaged, to realize the transmission of power. (See

Figure 3-33)

Figure 3-33

109

STEERING BRAKE | STRUCTURE & PRINCIPLE

3.7 STEERING BRAKE

This machine uses the wet, belt-style floating brake with a hydraulic booster.

A-A

B-B

Figure 3-34

No.

Name

No.

Name

No.

Name

Brake cover

Cover

Lever

Rock arm

Studs

Tail end

Rock arm

Adjusting spring

Brake lining

Spring

Cover

Brake band

Slide valve

Adjusting bolt

Spring

Valve body

Bracket

Bushing

Piston

Lever

Spring seat

Rock arm

Block

Its role is to hold the steering clutch’s outer drum tightly, to stop the final drive’s gear from rotating,

so as to let the vehicle turn or stop.

110

STRUCTURE & PRINCIPLE | STEERING BRAKE

3.7.1 WORKING PRINCIPLE

When the vehicle moves forward, the steering clutch’s outer

drum rotates forward (See Figure 3-35). Slightly apply brake

force on the brake pedal, the clearance between the brake

band and the outer drum will be reduced until certain points

are in contact. Due to the friction force, the upper part of the

brake band pushes against the tail end, to let Pin A enter the

Forward

groove of lever (15). If the brake force continues to be applied,

rotation

lever (17), Pin B, and lever (15) will move in the arrow direc-

tion, to hold the outer drum tight. At this point, A is the fulcrum

of rotation.

Figure 3-35

When the vehicle moves in the reverse direction, the clutch’s

outer drum rotates backward (See Figure 3-36), whereas lever

(17), Pin B, and lever (15) move in the direction indicated in

the figure, to hold the outer drum tight. But at this point, the ro-

tation fulcrum has already been transferred Point C.

The brake results of the two are basically the same.

Backward

rotation

Figure 3-36

3.7.2 SERVO MOTOR VALVE’S WORKING PRINCIPLE

The use of the servo motor valve can dramatically reduce the

brake operation force of the driver. During braking, rock arm (2)

pushes slide valve (5), to make the clearance between slide

valve (5) and piston (7) disappear, and the oil pressure from

the pump pushes piston (7) to operate rock arm (8) to realize

braking. But due to the movement of piston (7), a clearance

will appear again between slide valve (5) and piston (7) for

sure. In order to ensure uninterrupted move, the brake pedal

must move continuously.

111

FINAL DRIVE | STRUCTURE & PRINCIPLE

3.8 FINAL DRIVE

This machine uses the two-stage straight gear reduction mechanism.

The role of the final drive is to increase the output torque through the two-stage reduction, and at the

same time, to transmit the power through the sprocket to the walking mechanism.

Figure3-37: The final drive’s mechanism of SD22S and SD22R

No.

Name

No.

Name

No.

Name

Drive disc

Hub

Floating oil seal

Bearing support

Drive sprocket

Oil seal cover

Primary driving gear

Sprocket hub

Floating oil seal

Primary driven gear

Driving wheel's nut

Oil seal cover

Secondary driving gear

Support

Casing body

Secondary driven gear

Cover

Half shaft

112

Shantui SD22. Operation and Maintenance Manual - 3