Design Idea and Practical Application of Hydraulic Gear Oil Pump
The hydraulic gear oil pump has radial force imbalance, and the deformation of the gear shaft is biased towards the low pressure area of the pump body, which may cause scraping and boring phenomenon, and at the same time make the floating of the shaft sleeve worse and reduce the working life of the bearing. The method of increasing the high-pressure drainage groove is used in the design of the side plate to increase the range of the high-pressure oil area of the gear pump.
Considering the actual working conditions of the hydraulic gear oil pump, the design of the floating combination shaft sleeve should be able to reduce the radial force of the gear pump, reduce the noise and provide axial compensation. Specific design ideas are as follows:
(1) The hydraulic pressing force should be greater than the hydraulic separating force, but it should not be too large. The actual pressing force is 1.2 times the separating force;
(2) The working surface of the combined shaft sleeve and gear has unloading grooves in the direction of import and export to avoid the phenomenon of oil trapping in the gear pump;
(3) Choose a reasonable oil circuit to minimize the radial force of the gear;
(4) The shaft sleeve should have good lubricity and can adapt to thin oil and even no oil lubrication conditions.
1. side panel design:
The material of the side plate can be selected from lead bronze, and it can be made of modified PTFE under limited conditions. The side plate and the combined pump body are connected by a stop table.
The hydraulic gear oil pump has radial force imbalance, and the deformation of the gear shaft is biased towards the low pressure area of the pump body, which may cause scraping and boring phenomenon, and at the same time make the floating of the shaft sleeve worse and reduce the working life of the bearing. In the design of the side plate, the method of increasing the high-pressure drainage groove is used to increase the range of the high-pressure oil area of the gear pump. Only 2 to 3 teeth at the pump inlet play a sealing role, so the radial force on the gear is partially balanced, thereby reducing Radial imbalance force.
The structure of the external gear pump leads to the phenomenon of trapped oil, and the opening of the unloading groove on the side plate is an regular method to slow down the phenomenon of trapped oil. Under the premise of ensuring that the import and export are not connected with each other, the trapped oil area is reduced through the outlet unloading groove and the pump outlet, and the trapped oil area is increased through the inlet unloading groove and the spring inlet. Reasonable design trapped oil area and unloading groove can greatly improve the working performance of gear pump. There are many specific design methods, which are not specific here.
2. practical application:
Due to the complex force of the actual shaft sleeve of the hydraulic gear oil pump, the calculation method of the resultant torque is quite cumbersome, and only one design idea is provided here to calculate the approximate formula. In the actual design process, we can refer to the above design ideas, using CFD simulation method to calculate the stress of the shaft sleeve in detail, which can further increase the design accuracy.