Common excavators are driven by internal combustion engines and electric driven excavators according to their driving methods. Among them, electric excavators are mainly used in high altitude hypoxia and underground mines and other flammable and explosive places.
According to different scales, excavators can be divided into large excavators, medium excavators and small excavators.
According to different ways of walking, excavators can be divided into crawler excavators and wheel excavators.
According to different transmission modes, excavators can be divided into hydraulic excavators and mechanical excavators. Mechanical excavators are mainly used in some large mines.
According to the purpose, excavators can be divided into different categories such as general excavators, mining excavators, marine excavators, and special excavators.
According to the bucket, the excavator can be divided into shovel excavator, backhoe excavator, dragline excavator and grab shovel excavator. Front shovel excavators are mostly used to excavate materials above the surface, and backhoe excavators are mostly used to excavate materials below the surface.
1. Backhoe excavator
The backhoe is the most common we have seen, backwards and downwards, forcing the soil to cut. It can be used for excavation below the stop working surface. The basic operation methods include: trench end excavation, trench side excavation, straight line excavation, curve excavation, excavation at a certain angle, ultra-deep trench excavation, and trench slope excavation.
2. Shovel Excavator
The shovel action form of the shovel excavator. Its characteristic is "forward and upward, compulsory cutting of soil". The front shovel has a large digging force and can excavate the soil above the stop surface. It is suitable for excavating dry foundation pits with a height greater than 2m, but up and down ramps must be set. The bucket of the front shovel is larger than the bucket of the backhoe of the same equivalent. It can excavate the first to third types of soil with a water content of not more than 27%, and it can cooperate with the dump truck to complete the entire excavation and transportation operation, and it can also excavate Large-scale dry foundation pits and mounds, etc. The excavation method of the front shovel excavator is based on the relative position of the excavation route and the transportation vehicle. There are two ways to excavate and unload the soil: forward digging, lateral unloading; forward digging, reverse To unload the soil.
3. Dragline excavator
Dragline excavators are also called cable shovel excavators. The characteristics of its excavation are: "backward down, cut soil under its own weight". It is suitable for excavating Class I and Class II soil below the stop surface. When working, use the inertial force to throw the bucket out, dig farther, the digging radius and digging depth are larger, but it is not as flexible and accurate as the backhoe. Especially suitable for excavating large and deep foundation pits or underwater excavation.
4. Grab shovel excavator
Grab shovel excavators are also called grab excavators. The characteristics of its excavation are: "straight up and down, cut the soil under its own weight". It is suitable for excavating Class I and Class II soil below the stop surface, and is often used for excavating foundation pits, caissons, etc. in soft soil areas. It is especially suitable for digging deep and narrow foundation pits, dredging old channels and digging silt in water, or for loading loose materials such as crushed stone and slag. Excavation methods include trench side excavation and positioning excavation. If the grab bucket is made into a bar shape, it can also be used to load ore blocks, wood chips, wood, etc. in a wood storage yard.
Today's excavators account for the vast majority of full-hydraulic full-slewing excavators. The hydraulic excavator is mainly composed of engine, hydraulic system, working device, walking device and electrical control. The hydraulic system consists of hydraulic pumps, control valves, hydraulic cylinders, hydraulic motors, pipelines, oil tanks, etc. The electrical control system includes a monitoring panel, engine control system, pump control system, various sensors, solenoid valves, etc.
The hydraulic excavator is generally composed of three parts: working device, upper body and lower body. According to its structure and use, it can be divided into: crawler type, tire type, walking type, full hydraulic, semi-hydraulic, full rotation, non full rotation, general type, special type, articulated type, telescopic boom type and many other types.
The working device is a device that directly completes the excavation task. It is hinged by three parts: boom, stick and bucket. In order to meet the needs of various construction operations, hydraulic excavators can be equipped with a variety of work devices, such as digging, lifting, loading, leveling, clamps, bulldozing, impact hammers, rotary drilling and other work tools.
The slewing and walking device is the body of the hydraulic excavator, and the upper part of the turntable is equipped with a power device and a transmission system. The engine is the power source of the hydraulic excavator. Most of the diesel is used in a convenient place, and the electric motor can also be used instead.
The hydraulic transmission system transmits the power of the engine to hydraulic motors, hydraulic cylinders and other actuators through the hydraulic pump, and pushes the working device to move, thereby completing various tasks.
