Dump truck structure
Dump truck is mainly composed of hydraulic dumping mechanism, carriage, frame and accessories. Among them, the hydraulic dumping mechanism and the structure of the carriage are different from each modification manufacturer. The structure of the dump truck is explained in two aspects according to the type of the carriage and the lifting mechanism.
1 Carriage type
The type of carriage structure can be roughly divided into different uses according to different purposes: ordinary rectangular carriage and mining bucket carriage (as shown in the figure below).
Ordinary rectangular carriages are used for bulk cargo transportation. The rear panel is equipped with an automatic opening and closing mechanism to ensure the smooth unloading of the goods. The thickness of the ordinary rectangular carriage is: 4~6 for the front plate, 4~8 for the side plate, 5~8 for the rear plate, and 6~12 for the bottom plate. For example, the standard configuration of the ordinary rectangular compartment of Chengli dump truck is: 4 sides at the front, 4 at the bottom, 8 at the rear, and 5.
The mining bucket carriage is suitable for the transportation of large-size goods such as large rocks. Taking into account the impact of the cargo and the collision of the building, the design of the mining bucket carriage is more complicated and the material used is thicker. For example, the standard configuration of the Jiangnan Dongfeng dump truck mining bucket compartment is: the front 6 sides, 6 bottom and 10, and some models have some angle steel welded on the bottom plate to increase the rigidity and impact resistance of the compartment. To
2 Type of lifting mechanism
The lifting mechanism is the core of the dump truck and the primary indicator for judging the quality of the dump truck.
The types of lifting mechanism are currently common in China: F-type tripod magnifying lifting mechanism, T-type tripod magnifying lifting mechanism, double-cylinder lifting, front top lifting and double-sided rollover, as shown in the following figure.
The tripod magnifying lifting mechanism is currently the most widely used lifting method in China, with a load capacity of 8 to 40 tons and a carriage length of 4.4 to 6 meters. The advantage is that the structure is mature, the lifting is stable, and the cost is low; the disadvantage is that the closing height of the floor of the carriage and the upper plane of the main frame is relatively large.
The double-cylinder lifting form is mostly used on 6X4 dump trucks. A multi-stage cylinder (generally 3~4 stages) is installed on both sides of the front of the second axle. The upper fulcrum of the hydraulic cylinder directly acts on the floor of the carriage. The advantage of double-cylinder lifting is that the closing height of the carriage floor and the upper plane of the main frame is relatively small; the disadvantage is that the hydraulic system is difficult to ensure the synchronization of the two hydraulic cylinders, the life stability is poor, and the overall rigidity of the carriage floor is relatively high.
The front jack lifting method has a simple structure, the closing height of the floor of the carriage and the upper plane of the main frame can be small, the stability of the whole vehicle is good, the pressure of the hydraulic system is small, but the stroke of the front jack multi-stage cylinder is large, and the cost is high.
The double-sided rollover hydraulic cylinder has better force and smaller stroke, which can realize double-sided rollover; however, the hydraulic pipeline is more complicated, and the incidence of rollover accidents is higher.
Dump truck selection
With the development of dump trucks and the improvement of domestic purchasing power, dump trucks are no longer universal dump trucks that can do all tasks in the traditional sense. From a design perspective, they are developed differently for different goods, different working conditions, and different regions. The product. This requires users to provide specific usage conditions to manufacturers when purchasing vehicles.
When choosing a chassis, it is generally based on economic benefits, such as: chassis price, loading quality, overload capacity, fuel consumption per 100 kilometers, road maintenance costs, etc. In addition, users should also consider the following parameters of the chassis:
① The height of the upper plane of the chassis frame from the ground. Generally, the height of the plane above the ground of the 6×4 chassis frame is 1050~1200. The larger the value, the higher the center of gravity of the vehicle is, and the more likely it is to cause a rollover. The main factors affecting this value are the tire diameter, suspension arrangement and the height of the main frame section.
② Rear suspension of the chassis. If this value is too large, it will affect the stability of the dump truck and cause a rollover accident. This value is generally between 500-1100 (except for rollover dump trucks).
③ The vehicle is reasonably matched and reliable in use
Post time: Oct-08-2021