Excavator is a multi-purpose earthwork construction machinery, which is mainly used for earthwork excavator and loading operation. It can also carry out land leveling, slope repair, hoisting, crushing, demolition, trenching and other operations. It is widely used in the construction of roads, railways, bridges, houses, airports, ports, water conservancy and other projects.
Excavators are divided into single bucket excavators and multi bucket excavators according to the operation process. According to the purpose, it can be divided into construction type or general type, mining type or special type. According to the power, it is divided into electric, internal combustion engine and hybrid. According to the transmission mode, it is divided into mechanical, hydraulic and hybrid types. According to the walking device, it is divided into crawler type, tire type and automobile type. According to the working device, it is divided into forward shovel, backhoe, pull shovel, grab shovel and hoisting.
The overall structure of hydraulic excavator includes power device, working device, slewing mechanism, control mechanism, transmission system, walking mechanism and auxiliary equipment. The power unit, main part of transmission system, slewing mechanism, auxiliary equipment and cab of hydraulic excavator are installed on the rotatable platform, which is usually called upper turntable or upper part. Therefore, the hydraulic excavator can be roughly divided into working device, upper turntable or upper part and lower part.
The working device mainly includes boom, stick, bucket, hydraulic cylinder, connecting rod, pin shaft and pipeline. The upper part mainly includes diesel engine, main hydraulic pump, main control valve, cab, slewing mechanism, slewing ring, swivel joint, turntable, hydraulic oil tank, fuel tank, control oil circuit, electrical part and counterweight. The lower part mainly includes track frame, track, idler, roller, carrier sprocket, final transmission and tensioning device.
