Common excavators are divided into two types: internal combustion engine-driven excavators and electric-driven excavators. Among them, electric excavators are mainly used in plateau hypoxia, underground mines and other flammable and explosive places.

According to different sizes, excavators can be divided into large excavators, medium excavators and small excavators.

According to different walking modes, excavators can be divided into crawler excavators and wheeled excavators.

According to the 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, excavators can be divided into front shovel, backhoe, dragline and grab shovel. Front shovels are mostly used to excavate materials above the surface, and backhoes are mostly used to excavate materials below the surface.

1. backhoe excavator

The backhoe is the most common we've seen, a back-down, forced cut. It can be used for excavation below the shutdown working surface. The basic operation methods are: ditch end excavation, ditch side excavation, straight line excavation, curved excavation, excavation with a certain angle, ultra-deep trench excavation and trench slope excavation.

2. Front shovel excavator

The shovel action form of a front shovel excavator. Its characteristics are "forward and upward, forced soil cutting". 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 of more than 2m, but up and down ramps must be set up. The bucket of the front shovel is larger than that of the backhoe excavator of the same equivalent, and it can excavate the first to third types of soil with a moisture content of not more than 27%, and cooperate with the dump truck to complete the entire excavation and transportation operation, and can also excavate the soil. Large dry foundation pits and mounds, etc. The excavation method of the front shovel is based on the difference between the excavation route and the relative position of the transport vehicle. There are two ways of digging and unloading: forward digging and side unloading; forward digging and reverse To unload soil.

3. Dragline excavator

Draglines are also called draglines. The characteristics of its excavation are: "backward and downward, cutting the soil under its own weight". It is suitable for excavation of Class I and II soils below the stop surface. When working, the bucket is thrown out by inertial force, and the digging distance is relatively large, and the digging radius and digging depth are large, 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 and Shovel

Grab excavator is also called grab excavator. The characteristics of its excavation are: "straight up and down, cutting the soil under its own weight". It is suitable for excavation of Class I and II soils below the stop surface, and is often used for excavation of foundation pits and caissons in soft soil areas. It is especially suitable for digging deep and narrow foundation pits, dredging old channels, excavating silt in water, etc., or for loading loose materials such as gravel and slag. There are two types of excavation: trench side excavation and positioning excavation. If the grab is made into a grid, it can also be used for loading ore blocks, wood chips, wood, etc. in the log yard.

The vast majority of today's excavators are fully hydraulic azimuth excavators. Hydraulic excavators are mainly composed of engine, hydraulic system, working device, traveling device and electrical control. The hydraulic system consists of hydraulic pump, control valve, hydraulic cylinder, hydraulic motor, pipeline, fuel tank, etc. The electrical control system includes monitoring panel, engine control system, pump control system, various sensors, solenoid valves, etc.

Hydraulic excavators are 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 other types.

The working device is the 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 working devices, such as excavation, lifting, loading, leveling, clamps, bulldozing, impact hammer, rotary drilling and other working equipment.

The slewing and traveling device is the body of the hydraulic excavator, and the upper part of the turntable is provided with a power device and a transmission system. The engine is the power source of the hydraulic excavator, most of which use diesel oil in a convenient place, and can also use an electric motor instead.

The hydraulic transmission system transmits the power of the engine to the hydraulic motor, hydraulic cylinder and other actuators through the hydraulic pump, and pushes the action of the working device to complete various operations.