1. Product Introduction

Hengjia dump truck, based on Isuzu 700P chassis, can be used on roads, mining roads, construction sites and other roads, suitable for transporting sand, earth, coal and other goods. The whole vehicle design completely relies on the advantages of the original chassis, fully considering the convenience and reliability of the product. It is a practical, reliable and powerful product.

2. Safety warning

1. Overloading is not allowed!

2. During the entire process of lifting and lowering the car body, the operator should not leave the control device.

3. Before lifting the car body for vehicle maintenance, in addition to supporting the car body safety support bar on the subframe, at least one auxiliary support bar must be erected on the ground to support the car body.

4. Do not drive with the lifting handle in the "lifting" or "mid-stop" position;

5. When the car is fully loaded, it is strictly forbidden to drive downhill at high speed or stop suddenly.

6. When unloading, pay attention to whether the rear tailgate of the car body is open, and be sure to pay attention to safety when opening the tailgate.

7. Lifting operations are not allowed on loose soil roads.

8. Lifting operations are not allowed on tilted roads.

9. It is strictly forbidden to drive the car body in a lifted state.

10. Do not use the inertial "flash" car body method to dump sticky goods, otherwise it will cause the tie rod to bend or the cylinder and other parts to be damaged.

11. Users of side-tipping dump trucks should note that the flip pins on the other side must be completely pulled out before lifting, otherwise the dump truck will be seriously damaged.

3.Structural description

The upper part of the dump truck is mainly composed of a subframe, a carriage, a hydraulic lifting mechanism and its accessories. The carriage includes a front plate, a rear plate, a side plate and a chassis; the hydraulic dumping mechanism includes a transmission shaft, an oil pump, a lifting valve, a hydraulic cylinder, an operating device, a limit device, a fuel tank and a pipeline, and a dumping mechanism; the accessories include a stabilizing mechanism, an anti-sway mechanism, a rear door opening and closing mechanism, a spare wheel lifting mechanism, and a protective device. The power of the engine is output by the transmission and the power take-off, and the oil pump is driven by the transmission shaft. The pumped hydraulic oil enters the hydraulic cylinder through the distribution valve. Under the push of the hydraulic cylinder, the carriage completes the lifting and dumping of the goods.

3.1 Subframe

It is a frame welded from profiles, consisting of two longitudinal beams, several cross beams and some connectors. The main function of the subframe is to connect and fix the carriage with the chassis, and is connected to the lower part of the lifting mechanism. It is the basic connector for the modification of the dump truck. The subframe adopts a trapezoidal structure and is welded. The rear end uses a wide tail connecting support beam, which improves the lateral torsional rigidity of the subframe, reduces the deformation of the main frame, improves the lateral rigidity of the whole vehicle during lifting and the rigidity of lifting, making the vehicle more rigid during execution and lifting.

3.2 Carriage

The carriage is composed of a front plate, a rear plate, side plates and a bottom frame. The rear plate is an upper suspension structure. When the carriage is lifted, the rear plate can be automatically opened under the action of the locking mechanism; the bottom plate is welded to the side plates on the top and connected to the lifting mechanism on the bottom.

3.3 Hydraulic system

The hydraulic system consists of: hydraulic cylinder, oil pump, distribution valve, operating valve, auxiliary oil tank and other components.

3.3.1 Hydraulic system lifting mechanism

1. Hydraulic cylinder 2. Cylinder support beam 3. Gear pump 4. Hydraulic oil tank 5. Lifting valve

6. High-pressure oil pipe 7. Low-pressure oil pipe 8. Manual valve 9. Limit valve

3.3.2 Rear door opening and closing mechanism

This mechanism is designed based on the principle that different assemblies rotate around their respective rotation centers to produce different displacements. When unloading the load, due to the difference in the rotation center and the rotation radius, the lock hook or lock plate gradually moves away intact during the movement, and the rear door opens under the action of gravity load and lateral pressure, and the load is unloaded; when the cargo box drops, the rear door drops to a certain angle under the action of gravity and automatically fits with the rear edge of the side panel. The lock hook or lock plate returns to its position under the action of the wire rope or pull rod (chain) and hooks the rear panel to lock the rear door.

3.3.3 Spare wheel lifting mechanism

In order to be able to remove the spare wheel and replace it for normal driving in a timely and convenient manner and meet the needs of different users, the spare wheel lifting mechanisms produced by the company include manual hydraulic spare wheel lifting mechanism, manual winch spare wheel lifting mechanism, manual sprocket spare wheel lifting mechanism, and electric spare wheel lifting mechanism.

Notes:

① Before using the spare wheel lifting mechanism, please carefully check whether the wire rope (chain) is round and whether the wire rope (chain) clip is securely fixed.

② The spare wheel lifting mechanism can only be used to lift the spare tire.

③ When lifting, people cannot stand directly under the tire to avoid accidents and personal injuries.

④ It is strictly forbidden to drop the spare wheel at high speed when landing.

4. Operation Specifications

4.1 How to operate a dump truck

The air control valve pneumatically activates the lifting valve to control the oil circuit. The air control valve has three positions:

A - "tip"

: Lifting

B - "hold"/"neutral"

: Mid-stop position

C - "lower"

: Descent

D - "Slow descent": Slow descent

"Tip" lifting

Push the air control valve lever to the lifting position, the hydraulic oil flows into the cylinder, and the cylinder extends out of the lifting box. Push the air control valve lever to the mid-stop position to interrupt the lifting and stop the box.

"Hold"/"Neutral" mid-stop position

When the air control valve lever is in the mid-stop position, the hydraulic oil will circulate between the oil tank and the hydraulic valve, and the oil cylinder will remain in the current position.

"Lower" descent

When the air control valve lever is in the descent position, the hydraulic oil flows back from the cylinder to the oil tank, the cylinder retracts, and the box descends.

“Slow descent”

When the operating lever of the air control valve is in the slow-down position, the hydraulic oil flows back from the oil cylinder to the oil tank at a low speed, the oil cylinder retracts slowly, and the box descends slowly.

4.2 Tipper Operation Precautions

Before lifting, make sure that there is no one in the vehicle working area. Lifting with the rear door locked or blocked will endanger personal safety. For 2-sided or 3-sided dump trucks: hinge pins without safety devices will cause personal safety threats. Dumping is a very dangerous operation and accidents may occur at any time. In order to minimize personal safety and vehicle safety hazards, please strictly follow the following operating specifications.

4.2.1 Lifting the body

·Remove the canvas on the body, which may block the rear door and hinder unloading.

·If the dump truck is equipped with a top opening system, please open the top opening before lifting the body.

For detailed operation, please read the top opening user manual.

·For three-turn dump trucks: Check whether both hinge pins are in the rear hinge bracket.

If not, swap one of the front hinge pins to the rear hinge.

·When unloading, if the rear door lock does not open automatically, please open it manually.

·Put the air control valve in the "lift" position

·When the cylinder barrel is shifted, please reduce the engine speed.

·Before the cylinder reaches the maximum stroke, reduce the engine speed to idle.

·When the cylinder reaches the maximum stroke (or the limit valve is activated), put the air control valve in the "mid-stop position".

4.2.2 Lowering the body

· Slowly put the air control valve in the "down" position. The air control valve and the hydraulic valve can jointly proportionally control the speed of the box body falling.

· After the box body is completely lowered, about 5 minutes later, turn the air control valve from the "down" position to the "mid-stop" position. This ensures that each cylinder is retracted into the base cylinder.

Note: If the engine speed is too fast, insufficient oil supply from the oil pump will cause damage to the oil cylinder and the oil pump. Never use sudden braking to unload sticky goods, which will cause serious damage to the vehicle body and hydraulic system. Before starting the vehicle, make sure that all lock hooks and canvas are fixed.

4.2.3 Rear door lock

Your dump truck may be equipped with a rear door locking device controlled by a mechanical, pneumatic or hydraulic mechanism. When the box body is raised and lowered, the mechanical lock will automatically lock or open.

The pneumatically controlled rear door lock works in the same way as the power take-off control method: 0-locked 1-open.

Note: The rear doors should be locked when the vehicle is not in operation.

5. Maintenance Guide

5.1 Overview

Before filling the hydraulic oil tank with hydraulic oil, please clean the filter first to prevent contamination of the hydraulic oil. If the hydraulic oil level exceeds the maximum scale of the oil level gauge, the tank will overflow.

If the dump truck is not used for a long time, please lubricate all rotating points regularly to prevent rust.

5.2 Hydraulic oil

To avoid damage to the hydraulic system, we recommend that the hydraulic oil viscosity (at 40℃)

be between 75-12mm/s and the maximum oil temperature should not exceed 80℃. You can also use hydraulic oil of the same grade provided by other suppliers.

5.3 Post-accident treatment

Check whether the hydraulic system is damaged (especially the oil inlet pipe, hydraulic oil tank and the joint between the oil pump and the power take-off). Check all air and oil connection parts for damage and leakage. If there is any doubt, do not lift the vehicle before checking it at the service station.

5.4 Maintenance

In addition to executing the maintenance schedule, for safety reasons, daily visual inspections and patrol inspections are helpful to detect hidden dangers early, thereby saving maintenance costs and reducing downtime.

Parts to check:

5.4.1 Wheels

Check whether the tire pressure meets the requirements and whether the nuts are tightened (tap with a wrench, the sound of loose nuts is duller). Check whether there are any foreign objects stuck between the tires, which may pop out when the tires rotate.

5.4.2 Chassis and upper parts

Check the overall condition for cracks and other signs of wear, the matching of some devices (such as cylinders) and the condition of their rotation points and mounting points.

5.4.3 Air brake and hydraulic system

Check the pressure and oil level, listen for any air leakage; observe whether there is any hydraulic oil dripping on and under the vehicle.

5.5 Lubrication points

The location of lubrication points on dump trucks varies from model to model.

The difference in the model of cylinder and body will also affect the location and number of these lubrication points.