Excavator main pump

First, Definition and function of the main pump for excavators

1. Definition: The main pump of the excavator is the core component of the hydraulic system of the excavator, which is responsible for converting mechanical energy into hydraulic energy and providing power for various actions of the excavator.

2. Function: The main pump of the excavator sucks in the hydraulic oil and transports it to the various hydraulic actuators of the excavator (such as hydraulic cylinders, hydraulic motors, etc.) after pressurization, so as to drive the bucket, boom, track and other parts of the excavator to carry out various actions.

Second, the type and structure of the main pump of the excavator

1. Type: There are various types of excavator main pumps, which can be divided into gear pumps, piston pumps, piston pumps, etc. according to the different structures and working principles. Among them, the piston pump has been widely used in excavators because of its high pressure and large flow characteristics.

2. Structure: The main pump of the excavator is usually composed of the pump body, plunger (or piston), oil distribution pan, transmission shaft and other components. The pump body is the main part of the main pump, and the plunger (or piston) reciprocates in the pump body, and realizes oil suction and oil discharge by changing the volume of the pump chamber. The distribution pan distributes the suction fluid to the individual hydraulic actuators and directs the return oil back to the tank.

Third, the working principle of the main pump of the excavator

1. Working principle: The working principle of the main pump of the excavator is based on the working principle of the positive displacement pump. When the propeller shaft drives the plunger (or piston) to reciprocate in the pump body, the volume of the pump chamber changes. When the plunger (or piston) moves backwards, the volume of the pump chamber increases, forming negative pressure, which sucks in the hydraulic oil; When the plunger (or piston) moves forward, the volume of the pump chamber decreases, and the hydraulic oil is pressurized and discharged. By constantly changing the volume of the pump chamber, the main pump of the excavator can achieve a continuous oil supply.

2. Control of flow and pressure: The flow and pressure of the main pump of the excavator can be controlled by adjusting the stroke of the plunger (or piston) and changing the speed of the transmission shaft. In practice, excavator main pumps are often used in conjunction with other components in the hydraulic system, such as relief valves, throttle valves, etc., to achieve more accurate flow and pressure control.

Fourth, maintenance and troubleshooting of excavator main pump

1. Maintenance: The maintenance of the main pump of the excavator mainly includes regular replacement of hydraulic oil, cleaning of the pump body and oil distribution pan, and checking the wear of the plunger (or piston) and transmission shaft. Regular replacement of hydraulic oil can maintain the cleanliness of the hydraulic oil and reduce the wear of the pump body; Cleaning the pump body and oil distribution pan can remove the impurities and dirt deposited in the pump body and keep the pump body working normally; Checking the wear of the plunger (or piston) and the drive shaft can detect and replace the severely worn parts in time to prevent the occurrence of failures.

2. Fault handling: The common faults of the main pump of the excavator include leakage of the pump body, insufficient pressure, insufficient flow, etc. When there is a failure, the cleanliness and viscosity of the hydraulic oil should be checked first, then the pump body and oil distribution pan should be checked for wear or damage, and finally the plunger (or piston) and transmission shaft should be checked to see if they are working normally. Based on the results of the inspection, the fault can be rectified by corresponding repairs or replacement of parts.

Main hydraulic pump diagram

Excavator hydraulic pump types