The plunger pump is the power element of the hydraulic system. It is driven by an electric motor and sucks oil from the hydraulic oil tank to form a kind of element that discharges the pressure oil and sends it to the execution element. Hydraulic pumps are divided into gear pumps, plunger pumps, vane pumps and screw pumps according to their structure. The following editor introduces the types of hydraulic pumps and the working principles of hydraulic pumps.
Varieties of plunger pumps
1. Plunger pump: smaller in size, simpler in structure, less demanding for oil cleanliness, and lower price; but the pump shaft is subject to unbalanced force, severe wear and large leakage.
2. Vane pump: It is divided into double effect vane pump and single effect vane pump. This kind of pump has uniform flow, stable operation, low noise, higher working pressure and volume power than gear pumps, and messier structure than gear pumps.
3. Plunger pump: high volume power, small leakage, can work under high pressure, mostly used in high-power hydraulic systems; but the structure is messy, the data and processing accuracy are high, the price is expensive, and the cleanliness of the oil is high.
Working principle of plunger pump
A pump is an energy conversion device that converts the rotating mechanical energy of the motor into hydraulic energy for output. Hydraulic pumps are operated based on the principle of changing the seal volume, so they are usually called positive displacement hydraulic pumps. Figure 2-l shows the working principle of a single plunger hydraulic pump. The plunger 2 is installed in the figure. A sealed volume a is formed in the cylinder 3, and the plunger is pressed against the eccentric wheel 1 under the effect of the tension spring 4. The prime mover drives the eccentric wheel 1 to rotate to make the plunger 2 reciprocate, so that the size of the sealing volume a is changed periodically. When a changes from small to large, some vacuum is formed, so that under the effect of atmospheric pressure, the oil in the oil tank will enter the oil cavity a by opening the check valve 6 through the suction pipe to complete oil absorption;