Hydraulic steering gearbox for truck

Shashi Jiulong Power Steering Co., Ltd is a manufacturer of steering gear with well-equipped testing facilities and strong technical force. 

With a wide range, good quality, reasonable prices and stylish designs, our products are extensively used in automobile industries. 

Our products are widely recognized and trusted by users and can meet continuously changing economic and social needs. In another way, the R & D team will help different customers re-developping the steering gear according to customers specific requirements.

We welcome customers, business associations and friends from all parts of the world to contact us for retail and OEM purpose and seek cooperation of mutual benefits.

Manufacture Capability 

Production equipments for assembly parts

Purpose of Using Steering Gear

1. To improve the manipulation convenience and security of the automobile.

Lighten the steering force of the steering wheel.

Improve the turning maneuverability and moving mobility of the automobile by reducing the steering circles. Because it is very easy to set the steering force of the steering wheel, It is convenient to determine the steering wheel circles according to the requirements of variant types of automobile in design.

Ensure the safe driving.

While going at a high speed,  if the front tyre bursts suddenly, the automobile can still be controlled by power steering.

2. To improve the amenity of automobile manipulation.

The driver can not feel the ground knocks against the tyre but feels smooth.

Principle Of Steering Gear

1. Brief Introduction

The power steering gear assembly consists of mechanical part and hydraulic part, actually the swerve is achieved by coaction of the two parts. The function of mechanical part is to make the force exerted on the steering wheel be delivered by the following route: steering wheel-steering column-input shaft-steering screw-steering nut-steering arm shaft(speed reduction)-steering rocker arm-cross-straight drag bar. The function of hydraulic part is to make steering wheel operation easy and to improve the operational stability.

2. Mechanical Principle

The steering force exerted on the steering wheel is delivered to the input shaft in the steering screw assembly and make it in rotation state, which is turned to be reciprocating motion via rolling-ball lead crew pairs between steering screw and steering nut, then it is changed to be the rotary motion of the steering arm shaft by rack-and-pinion between steering nut and steering arm shaft, subsequently, the rocker arm swings and the motor steering can be fulfilled by cross-straight drag bar system.

Maintenance& Adjustment of Self-Adjusting Safety Valve

After the parts of the steering system have been maintained or replaced, the connectors are altered. The relief position of the relief valve must be readjusted, since otherwise it may not relieve pressure in the full stroke.

Reset of Left Steering Pressure relief mechanism

Shut down the engine and raise the steering bridge, ensure the wheels leave the ground. Keep the steering wheel in linear driving state. Loosen the pinch nut on the central regulating stud and screw it whole into the steering gear. Keep rotating the steering wheel right until it stops, then screw regulating stud out to initial point. Finally tighten the pinch nut.

Reset of Right Steering Pressure relief mechanism

Shut down the engine and raise the steering bridge, ensure the wheels leave the ground. Loosen the pinch nut on the shoe bolt, screw the shoe bolt out by ten teeth, then screw it in to initial point and tighten the pinch nut.

Knowledge of Preventive Maintenance 

Operating Oil

Premium hydraulic oil is very important to ensure the good effectiveness of power steering gear. Users must follow the oil specifications strictly. It is recommended that No.8 hydraulic transmission oil be used on power steering gear. If the ambient temperature is above 0℃, N32 general hydraulic oil can be used as substitute; conversely, No.10aircraft fluid (HY-10) can be used as substitute. Also the ATF-Ⅲ automobile self-acting transmission oil is recommended, which has good performance.

Attention: Do not use oil mixture, since otherwise the power gear can not operate normally, even the parts may be damaged. When changing oil, all oil in the system must be discharged to the specification, then feed new oil in it.

Oil Change Period

After the automobile goes 5,000 kilometers, first oil change should be done and the oil filter should be cleaned. Since then, the hydraulic oil should be checked and changed periodically according to road condition, mileage, etc. cleanliness of the oil filter should be provided.

Oil Change Rules

1. Raise the fore axle of the automobile and make the fore wheels leave the ground.

2. Uncover the oil tank, twist off the outlet bolt (the connecting bolt of oil return and the steering gear) of the steering gear in order to drain the residual oil in oil pump and oil tank ( if necessary, idle the engine).

3. Rotate the steering wheel right and left to limiting position several times until there is no oil flows outlet of the steering gear.

4. Put the outlet bolt and oil return line back in original position and tighten then (packing plate needs to be installed).

5. Remove the oil filter from the oil tank and clean it.

6. Put the oil filter back into the oil tank.

7. Feed new oil into the oil tank.

8. Idle the engine, Rotate the steering wheel right and left to limiting position several times until the oil surface doesn’t descend and no bubble occurs.

9. Refill oil to the liquid level mark.

10. Tighten the upper cover of the oil tan.

Clearance Adjustment between Output Shaft Geared Sector and Gear Rack

The clearance between the geared sector of steering arm shaft and the gear rack of the steering nut has been adjusted properly in advance. Normally it need not to be readjusted. After they are worn or the steering gear is completely repaired, they need to be readjusted. When adjusting it, the input shaft and the steering arm should be disconnected from the automobile. See the following information for details.

Dust Shield and Dust Seal

Check the dust shield and dust seal on both ends of input shaft and steering arm shaft, which can prevent the dust entering the steering gear through the open rotation shaft. Replace them if damage happens. Fill the cavity of the dust shield and the dust seal with grease lubricant.

Matters Need Attention

When repairing the steering gear, the following things should be noticed:

1. Put the automobile on the level ground and brake it.

2. Shut down the engine.

3. Switch off all power supplies according the automobile manufacturer’s instruction book.

4. Never remove or install the hose with pressure unless the pressure system is vented completely in case of injury.

5. Do not try to install, remove, and disassemble the assembly and parts before you know how to repair it well. Suitable tools should be used and correlative safety measures should be taken.

6. Spare parts in the maintenance kit provided by JiuLong CO. LTD are the most desirable for use. Their parameters such as specification, type and strength should be the same with those original parts’.

7. The internal key parts should not be replaced, even remachined or welded.

8. Be sure that all systems and parts reset to correct positions just before starting the automobile.

9. Do not rotate the input shaft at will before installing the direction gear to avoid changing the initial of the safety valve.(In Principle, the input shaft can be rotated by plus-minus 1.9 circles and does not touch the safety valve)

The operating instruction manual offered by our company should be observed strictly when installing the steering gear for the first time or repairing the steering system.