The is mainly composed of power system, transmission system, working device, working hydraulic system, steering hydraulic system, vehicle frame, operation system, braking system, electrical system, cab, panel and air conditioning system. The working principles of the first five systems are described in detail below.
Simple analysis of the working principle of wheel loader
The is mainly composed of power system, transmission system, working device, working hydraulic system, steering hydraulic system, vehicle frame, operation system, braking system, electrical system, cab, panel and air conditioning system. The working principles of the first five systems are described in detail below.
One, power system
The power system of a loader is composed of a power source diesel engine and an auxiliary system to ensure the normal operation of diesel engine, including diesel engine, fuel tank, throttle control assembly, cooling system, fuel line and so on. The diesel engine performs the normal walking function through the double variable drive system, and drives the working device to complete the working actions such as shovel, lift and turn over by driving the working hydraulic system. By driving the steering hydraulic system, it deflects the frame to complete the steering action.
Two. Transmission system
The transmission system consists of torque converter, gearbox, drive shaft, front and rear drive bridge and wheel and so on. Automatically adjust the output torque and speed of the drive system, the loader can automatically change the speed and tension according to the road conditions and the size of the resistance, in order to adapt to changing conditions. After filing, from the start to the maximum speed between the gear can be automatic stepless speed change, steady start, good acceleration performance. When there is a slope or a sudden road obstacle, no shift can be needed to automatically slow down the traction force and travel at any small speed to cross the obstacle. When the external resistance is reduced, the rate of operation can be speeded up quickly. When the material is spade, the material can be cut into the heap at a large speed and automatically decelerate with the drag to increase the traction force to ensure the cut in.
The output power of the engine is transmitted to the gearbox through the torque converter. After the gearbox's speed change, the specific speed can be rotated through the transmission shaft to drive the front axle and the wheel to achieve the function of walking at a certain speed.
Three. Work device
The working device of the loader consists of four parts, the bucket, the arm, the rocker arm and the pull rod. The arm is a single plate structure, the rear end is supported on the front frame, the front end is connected with the bucket, and the middle is connected with the cylinder of the moving arm. When the arm cylinder is telescopic, the moving arm is rotated around the pin axis of the rear end to achieve the lifting or falling of the bucket. The rocker arm is a single rocker arm mechanism, and the middle part is connected with the boom. When the rotary bucket oil cylinder expands, the rocker arm rotates around its middle supporting point, and the bucket is turned up or down through a pull rod.
The scope of application of wheel loader
The production practice at home and abroad has proved that the wheel loader is suitable for the following aspects:
1. It is used for loading, pushing and discharging, lifting and pulling in the construction of opening and stripping of open pit mines, railway construction and repair roads.
2, small and medium-sized open-pit mines are used to replace excavators and automobiles as main mining, loading and transporting equipments. They can be combined with cars or ore mines at crushing stations.
3, in some large opencast mine, with the excavator under complex conditions (such as sorting, mining working face end and blast scattered, mining trench etc.) for mining equipment and other auxiliary operation.
4. It can be used for mining, loading and transporting joint operations for large sloping working face to complete difficult mining work.
The common tire and crawler type two front loading machines have their own characteristics. Although the tracked front loader has better traction and shovel force, better cross-country and climbing performance, but its speed is low and inflexible. Sometimes transferring stations need trailers, and the construction cost is relatively high. Therefore, open pit mines seldom use crawler Front loaders. The most commonly used type of loaders in the world is the tyre loaders, so they produce more quantities, and the production technology is developing very fast. The largest bucket capacity has reached 40m3.
Advantages and disadvantages of wheel loader
In the open pit with suitable conditions, the use of wheel type reloader can highlight the advantages of the following aspects:
1. The tire front loader has fast walking speed, short working cycle time and high loading efficiency. According to mine calibration data, bucket capacity is above 5~8m3 pre installed at speeds of up to 35km/h times faster than 30~90 excavator, each working cycle is only 40~45s, the average number of production capacity of up to 3500~4000t, the average labor productivity can be increased by 50%~100%.
2, the tire type front loader is lighter in weight, equivalent to the same bucket capacity excavator quality 1/8~1/6, saving a lot of steel, the manufacturing cost is only 1/4~1/3 of excavator, and the price is cheaper than that of excavator. It can reduce investment in mine production equipment and reduce the proportion of fixed assets.
3, tire type front loader climbing ability, flexibility is good, can be used in the slope face excavator loading operation is not allowed, especially can also work in the new mining sites lack of electricity, which can speed up the mine development and construction and shorten the construction period.
4, the depreciation period of the tire mounted front loader is only 1/4~1/8 of the excavator. After 5~6 years of work, the new advanced equipment can be replaced, which is convenient for mine management and maintenance, and is conducive to the upgrading of the equipment.
5, the tire type front loader is easier to operate than the excavator, so it can shorten the training time of drivers. At the same time, a loader needs only one driver to operate, which saves manpower, material resources and financial resources.
However, compared with the excavator, the front loading machine also has some disadvantages in production.
(1) the tire front mounted excavator has less excavating ability than the excavator. When the blasting quality is not good and the block is large, its working efficiency will obviously decrease. For the material with strong viscosity needs loosening, the shovel operation and other auxiliary operations can be carried out.
(2) compared with the , the working mechanism of the front loader is smaller. Due to the limitation of safety conditions, it is not suitable for the working face with high explosive piles. The stope height is generally not more than 12m.
(3) the tire of the loader has faster wear and shorter service life. In recent years, though some measures such as adding protection chain link or adopting cushion track plate can reduce tire wear, but tire life is also about 1500h. The proportion of tire cost in production equipment cost is still large (about 40%~50%, even up to 60%).
