Summary of performance failure symptoms of hydraulic plunger pump and oil pump and abnormal problems in daily use

It is inevitable to encounter various problems in the daily use of Rexroth plunger pump oil pumps. The editor has summarized some performance concerns, fault symptoms and abnormal problems in daily use. It is recommended to purchase a Rexroth hydraulic pump from a hydraulic pump manufacturer that can provide technical support and perfect after-sales service. After all, the network information is relatively scattered, and the accuracy of the solution cannot be guaranteed.

1. What is the reason for the abnormal beating of the pilot valve core of the Rexroth oil pump?

The main valve core is opened by using the pressure difference formed by the liquid flowing through the damping orifice. Once it is blocked, the main valve port will be normally open and the pressure cannot be adjusted. If the pilot valve hole is blocked, the oil pressure difference between the upper and lower chambers of the main valve is almost equal, and the main valve core cannot be lifted and cannot overflow.  

2. How to close the flow control valve of the Rexroth plunger pump?

Turning the spring that adjusts the flow clockwise to the end closes the flow adjustment function, and the X port is also blocked. The oil circuit of port B into the system should also be closed, set the pressure of the pump and then open port B to feed oil into the system. Due to the different control methods of various types of Rexroth plunger pumps, it is recommended to directly seek technical support from the manufacturer to avoid misoperation.

3. Rexroth piston pump testing standards What items need to be tested?

All assembled Rexroth plunger pumps must pass the hydraulic pump test equipment jointly developed by our company to test the sealing performance, efficiency, full load, overspeed, noise, pressure swing, displacement verification, etc. of the Rexroth plunger pump. Only in full compliance with the design specifications can be put in and out of the warehouse.

4. What are the symptoms of the Rexroth variable hydraulic pump sucking oil into the air?

If the Rexroth variable hydraulic pump sucks air, its external appearance may have symptoms such as noise, insufficient pressure, instability, vibration, and hydraulic oil heating.

5. What is the difference in performance between domestic Rexroth hydraulic pumps and imported hydraulic pumps?

The domestic hydraulic pump independently developed and manufactured by our company can be seamlessly connected to the imported hydraulic pump. Whether it is appearance, structure, oil port, installation size, etc., the only difference in performance is Due to the difference of domestic materials, the service life is reduced by 30%. However, the price of domestic Rexroth hydraulic pumps is usually around 40%.

6. What conditions should the Rexroth hydraulic pump meet for normal operation?

The external oil drain pipe should ensure that the Rexroth plunger pump and the oil motor casing are filled with oil to prevent the oil in the casing from pouring back into the oil tank during parking, such as making the oil drain port higher than the casing.

(1) The viscosity of the oil should meet the requirements. The viscosity index of oil is high, the viscosity change with temperature is small, the viscosity index is low, the viscosity change with temperature is large. The viscosity index of the working oil of the domestic Rexroth plunger pump is generally required to be above 90, and the better one is above 100.

(2) Keep the oil clean and maintain a certain oil filtering accuracy.

(3) The oil suction pipe should be short and straight, and the pipe diameter should be slightly larger than the pump inlet.