The entire machine can be divided into three major parts structurally: chassis assembly, working device assembly, and upper platform assembly.
Chassis assembly composition and function: 1. Support the upper weight of the entire excavator. 2. The power source and actuator for walking and turning. 3. The reaction force during excavation of the supporting working device.
The chassis mainly consists of: 1. lower frame body (welded parts), 2. four wheel belt (guide wheel, drive wheel, carrier roller, support roller, and track). 3. Bulldozer and oil cylinder. 4. Central swivel. 5. Slewing raceway ring (slewing bearing). 6. Travel reducer and motor.
Frame structure and function: The frame body (welded part) is the main body of the entire chassis, which bears all internal and external forces and various moments. The working conditions are extremely harsh, and the requirements for the parts are high. There are certain requirements for the flatness of the left and right track beams, otherwise there will be significant lateral forces that are detrimental to the structural components.
Guide wheel and tensioning device: Guide wheel and tensioning device: Guide the direction of track movement, adjust the degree of track tensioning, and reduce resistance.
Carrier roller and supporting roller: The carrier roller plays the role of supporting the track. The supporting wheels serve to support weight.
This structure is maintenance free and does not require the addition of lubricating grease. There are slight differences in the structural forms of the carrier and support wheels used in large excavators, but the principles are the same.
Slewing support - connects the upper and lower parts of the vehicle, allowing the upper part to rotate around the lower part while bearing overturning torque. The rollers (balls) inside the track circle need to be lubricated regularly, in two forms: adding grease from the side and adding grease from the top.
Walking motor+reducer: Provides powerful power (torque) to drive the sprocket and track, enabling the excavator to complete walking and turning movements.
Central rotary joint (function) - connects the hydraulic oil circuits of the upper and lower vehicle, enabling the upper vehicle to rotate around the lower vehicle normally.
Maintenance items for chassis components:
Regularly add lubricating oil to each lubrication point; Clean up dirt at any time; Check the tightening status of fastening bolts at all times; Regularly check the lubricating oil level of the walking reducer; Regularly check the tension of the track and the wear of the chain rail joints.
