HW19710T Series Transmission

Operation Instruction

CHINA NATIONAL HEAVY DUTY TRUCK GROUP CORP., LTD. (CNHTC)

Preface

It took decades for CHINA NATIONAL HEAVY DUTY TRUCK GROUP CORP., LTD. (CNHTC) to develop a new generation of HW19710T Series Transmission which is specially used for heavy-duty truck. CHINA NATIONAL HEAVY DUTY TRUCK GROUP CORP., LTD. (CNHTC) has a completely independent intellectual property rights about this series of transmission. The main gearbox of HW19710T Transmission adopts single intermediate shaft, full synchromesh structure; the auxiliary gearbox adopts planetary reduction mechanism, which have resulted in greater load carrying capacity, and structure reliability. Integrated small cover makes the gears clear, and gear-shifting flexible.

At present, this series transmission is applicable to the engine of heavy-duty vehicle with the power range from 336 to 420 hp. It is the top choice for the domestic heavy-duty truck.

All copyrights on this Operation Instruction reserved to CHINA NATIONAL HEAVY DUTY TRUCK GROUP CORP., LTD. (CNHTC), and it has a final explanation.

Please consult the latest version of the Operation Instruction at any time. It is subject to change without prior notice.

Warning

◆ In order to avoid individual injury or causing fault and damage to the equipment, please operate the transmission according to the designated procedure;

◆ Before the vehicle starting, the drivers shall be in the driver’s seat; place the shift lever in neutral, and use hand brake;

◆ Before the vehicle is operating or the engine running, please leave the cab, place the shift lever in neutral, and use hand brake to lock the wheels;

◆ When parking or leaving the cab, place the shift lever in neutral, and use hand brake;

◆ Never release the hand brake to shift a gear when the pressure of the vehicle does not increase to the correct level;

◆ Never make the vehicle slide too long when the transmission is in neutral;

◆ When operating power take-off (hereinafter referred to as “PTO”), immediately depress the clutch pedal to the floor after pressing the PTO switch, after a while, release it after the PTO works properly.

I. Main Parameters of HW19710T Series Transmission

Maximum input torque:

HW19710T: 1900Nm

HW19710TC: 2100Nm

Maximum input speed: 2600rpm

ModelGearbox ratios

1 2 3 4 5 6 7 8 9 10 R1 R2

HW19710T

14.3

6

10.6

6

7.87

5

5.82

4.38

3.28

2.74

1.80

1.33

1.00

14.0

1

3.20

HW19710TC

10.7

9

8.01

5.92

4.38

3.29

2.47

1.83

1.35

1.00

0.75

10.5

3

2.41

Mass: 430kg Fuel charge: 15L（15.5L） Overall length: 1030mm

Note: 1. Lubricant and clutch release device are not included in the mass;

2. Length refers to end face of front edge of the clutch to the end face of output flange;

3. The fuel charge in the brackets is the fuel mass when adding the PTO.

Model of PTOGear ratio

HW19710T HW19710TC

HW50-01 0.924 0.694

HW70-01 0.948 0.713

II. Numbering Rule

HW 19 7 10 T C

Overgear (It is direct gear if there is on this position)

Synchronizer

Number of forward gear

Serial No., heavy-duty transmission series

1% of the torque, use 1/10 if less than 3 digits

Brand

III. Main Sectional View of HW19710T Transmission Assembly

Figure. 1

External Connection Dimension Figure of HW19710 Transmission

Figure. 2

IV. Mechanism Diagram of HW19710T Transmission and Route Diagram of Power Transmission

Gears

Figure. 3

V. Structure of HW19710 Series Transmission

HW19710T series transmission is composed of two-stage structure, i.e. main gearbox and auxiliary gearbox. There are 5 forward gears in the main gearbox, and 2 gears in the auxiliary gearbox. Altogether constitutes of 10 forward gears and 2 reverse gears.

1. Structure of Main/Auxiliary Gearbox of HW19710T Series Transmission

Main gearbox of HW19710T series transmission adopts single intermediate shaft, all synchromesh structure; the auxiliary adopts planetary reduction mechanism. The power is input via input shaft, and then transferred through intermediate shaft, finally output through planetary reduction mechanism of auxiliary gearbox.

The gears in the main gearbox adopt large module and all helical gear design, with high coefficient of contact ratio. All the gears adopt forced shot-peening. This can greatly enhance the bending stress of the gears. Due to adopting of single intermediate shaft, it is not necessary to align the teeth during assembling.

The auxiliary gearbox adopts planetary reduction mechanism, whose strong points are transmission of large torque, wide range of gear ratio, long service life and compact structure. And when the auxiliary gearbox is in high gear, the entirety of planetary mechanism revolves around the shaft center. The planetary gears are only with revolution, without rotation, at this time, the transmission efficiency of the planetary mechanism is almost 100%, with less oil mixing loss.

2. Gear-shifting Mechanism of Synchronizer

The first, second and third speed gear in the main gearbox and rear auxiliary gearbox of HW19710T series transmission adopt double-cone lock ring synchronizer, the fourth and fifth gear adopt single-cone lock ring synchronizer, the structure is shown in Figure. 4. It is composed of the following parts:

1- Synchronized gear

2- Synchronous conical ring

3- Locking piece seat of synchronizer

4- Locking piece of synchronizer

5- Locking piece spring of synchronizer

6- Gear sleeve

7- Tooth holder

Figure. 4

In order to reduce transmission noise of the vehicle and fuel consumption per 100 km, eliminate gear-shifting impact, prolong the service life of gear and power train system, and shift a gear smoothly and quickly, all adopt synchronizer structure except reverse gear.

3. Operating Mechanism

HW19710T series transmission is remote-controlled, with two types, i.e. single-lever control and double-lever but single control. The main gearbox is manual operation, and the rear auxiliary gearbox is air control. Figure 6 is Location Plan of Gear-shifting Handle, and Figure 7 is Gear-shifting Handle Diagram. When pre-selector valve of handle is in the position of L, you could shift to 1-2-3-4-5-R1 gear; and when in the position of L, you could shift to 6-7-8-9-10-R2 gear.

Figure. 6 Figure. 7

4. Air-controlled System

Air supply is bifurcate compressed air (0.7 ～ 0.8Mpa) from the finished vehicle. Air Passage Diagram of Control Mechanism is as shown in Figure 8: When the gear-shifting handle is in the position of L, one air supply, i.e. compressed air, goes through S of gear-shifting handle to P, and then enter into lockup valve cylinder 4; simultaneously, the other air supply of the finished vehicle enters into Valve H via Port 1, and enters into the lower port of RANGE

GEAR cylinder of the transmission through Port 2 of double-H valve, the auxiliary gearbox switches to low gear (the cylinder is in a condition of constant ventilation). When the gear-shifting handle is in the position of H, there is no compressed air entering into lockup valve cylinder 4; the compressed air enters into double-H valve through Port 1, and enters into the upper port of RANGE GEAR cylinder of the transmission through Port 3 of double-H valve, the auxiliary gearbox switches to high gear (the cylinder is in a condition of constant ventilation).

Note: Only when it is in neutral, high/low gear switch of gear-shifting handle works.

Figure. 8

5. PTO Mechanism

HW19710T series transmission adopts power take-off of counter shaft in the main gearbox, being rear power take-off, whose direction of output turning is the same as that of engine. The PTO communicates with the inner chamber of the transmission, adopting compulsory lubrication, and no necessary to additionally fill lubricant.

At present, the matching PTOs are: HW50-01 series and HW70-01 series.

6. Lubrication System of the Transmission

HW19710T series transmission adopts compulsory lubrication, splash lubrication, spraying lubrication of oil-splashing pipe. Compulsory lubrication pump with heavy flow flows to each part to make the gears, synchronizer and bearing lubricate sufficiently. Oil filter is installed on the outside of the

Neutral sensor

to lower port of RANGE GEAR cylinder of the transmission

to upper port of RANGE GEAR cylinder of the transmission

High gear range

Low gear range

Black

Red

transmission, making sure that the lubricant is clean. In addition, oil cooler interface is left on the transmission housing. Oil cooler is optional.

Figure. 11

V. Disassembling and Assembling of HW19710T Series Transmission

Please see “Maintenance Manual” compiled and published by our company for disassembling and assembling of HW19710T series transmission.

VI. Maintenance and Precautions for HW19710T Series Transmission

i) Operating Requirements

It is very important to operate the transmission correctly and reasonably, and maintain it regularly, which will guarantee the vehicle running reliably and extend its service life. Please comply with the following requirements:

1. Lubricant Brand and Type.

The transmission shall be filled with 85W/90 (Grade GL-4) vehicle gear oil.

2. Correct Oil Level.

Make sure that the oil level shall parallel to the sight glass. Check the oil level through the sight glass at the side of the transmission housing. The oil level shall be correct just when the overflowing occurs on the port. Oil charge shall be about 15L（15.5L when adding PTO）.

3. Inspection of Oil Level

Check the oil level regularly. The vehicle shall stop on the level road when checking the oil level. Due to volume expansion of the hot oil, you cannot immediately check the oil level just after the running of the vehicle in order to measure it correctly. You can check it when the oil level is steady and the oil is a little bit cool.

External connection to oil cooler interface

Oil filter

Oil-splashing pipe

4. Replenish the Lubricant

In order to prevent chemical reaction between different types of lubricant, when replenishing the lubricant, make sure that what filled shall be of the same as the original.

5. Oil Changing Period

When changing the lubricant, primarily, drain the original lubricant, and clean the filter screen assembly.

It is necessary to change the lubricant after the new transmission has run 2000 to 5000 Km.

Check oil level and leakage for service every 10000 Km, replenish it if necessary, and clean the filter screen assembly.

Change the lubricant and filter assembly for service every 30000 Km (or filter cartridge).

6. Grease Filling Requirements for Clutch Release System

Push-type clutch release bearing slides on the support face of the input shaft to realize engagement and disengagement of the clutch. It is necessary to fill lithium grease between matching surfaces. There is a metric taper thread grease nozzle at the side of the front housing of the transmission. Fill lithium grease for service every 10000 km. Open the lower cover board of the front housing, fill the grease until you can see that the grease could be squeezed out from the both ends of the releasing bearing.

If there in no lubrication hose at the side of the front housing of the transmission, what the transmission used is pull-type clutch release bearing. It is not necessary to fill grease.

7. Working Temperature

During continuous working of the transmission, the maximum temperature shall not be more than120℃, and the min. shall not be lower than -40℃.

When the working temperature exceeds 120℃, the lubricant will decompose, and that will shorten the service life of the transmission.

Any one of the following conditions will cause the working temperature of the transmission over 120℃:

<1> Operate continuously at the running speed of less than 32km/h.

<2> High engine speed.

<3> High ambient temperature.

<4> Eddy current surrounds the transmission.

<5> Exhaust system is too close to the transmission.

<6> Over-speed running with high power.

8. Tilt Angle of Operating

The lubrication may be insufficient if the tilt angle of transmission operation.

(Tilt angle of operating is equal to that installation angle between the transmission and the chassis plus slope angel).

9. Towing or Sliding

Do not coast with the transmission in neutral when the clutch pedal is depressed;

If it is necessary to tow the vehicle, you can pull out half a shaft or uncouple drive shaft, and also you can make the driving gear towed away the ground.

10. It is strictly forbidden that the transmission shifts from high gear range to low gear range when the speed exceeds 26km/h.

2) Precautions:

1. The synchronizer is a transmission; thus, when shifting a gear, the clutch shall be in thoroughly separated condition, and only one step on the pedal, the shift lever could be shifted in place. Never allows to shift gears if the clutch is not in thoroughly separated condition; otherwise, the synchronizer will be damaged.

2. When handle ball of HW19710T transmission switches between low and high gears, you shall consciously stop for a while to be good for auxiliary gearbox of RANGE GEAR switching from high gear to low gear smoothly.

3. According to the road condition for finished vehicle, the vehicle shall start off in first or second speed gear.

4. It uses conical roller bearing in the shaft support of the transmission. When assembling the conical roller bearing indoors, please leave some pre-tightening force. The adjustment of the pre-tightening force complies with Maintenance Manual.

5. There are 2 oil-drain plugs and 2 oil level plugs in the transmission. When changing the oil, please park the finished vehicle in the horizontal position, fill the oil from two oil level ports, simultaneously, check the oil level.

6. The transmission could assemble lubricant cooler. When assembling, the lubricant cooler shall be filled with the lubricant.

7. Filter is the standard equipment. Change the filter cartridge irregularly according to the service condition of the finished vehicle.

8. If the transmission is found with abnormal noise, meshing from dislocating, out of control or heaviness during use, you shall immediately stop the vehicle to check it. The vehicle could continue running after troubleshooting.

9. During the period of “Three Guarantees”, the user shall not dismantle, assemble or modify it by him.

This Manual is compiled by Technical Center, China National Heavy-duty Truck Group Datong Gear Co., Ltd.

Add.: No. 81 Xinkaibei Road Datong, Shanxi Province

Tel.:0352-2416352、2416353

Fax: 0352-2416444

Post code: 037006

Free Service Hotline: 8008062208

Website: http://www.dcgroup.com.cn

Email:dc680@dcgroup.com.cn

Notice: The words, pictures and parameters are only for reference.