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How does a gear pump work? Posted by : admin / Posted on : Jul 29,2021

In some automation or equipment manufacturers, we often encounter gear pumps, but we generally do not have a very deep concept of gear pumps. So Heilongjiang garden machinery manufacturers will talk about the principle of gear pumps today, and what kind of occasions are they used for? A gear pump will be used.
Gear pump is a widely used hydraulic pump. Its main advantages are: simple structure, reliable work, strong self-priming ability, and insensitive to oil pollution. Its disadvantages are: large pulsation of flow and pressure, large noise and immutable displacement. Because the gear is a symmetrical rotating body, the allowable speed of the gear pump is higher, and the speed can reach 300o/min. According to the working pressure, gear pumps are divided into three categories: rated pressure 2.5MPa is called low pressure gear pump; rated pressure is 16-20MPa, called medium and high pressure gear pump; rated pressure up to 32MPa is high pressure gear pump. According to the form of gear meshing, gear pumps are divided into two categories: external gear pumps and internal gear pumps.
The structure and working principle of external gear pump
The external gear pump is composed of two involute gears with the same parameters, pump body, end cover, transmission shaft and other parts.
A sealed working chamber is formed between the pump body, the front and rear end covers and gears, and the left and right chambers are separated by the tooth surface contact lines of the two gears to form an oil suction and discharge chamber. When the gear rotates in the direction shown in the figure, the teeth on the right side gradually withdraw from the meshing, that is, the teeth of the main and driven gears withdraw from the valleys of each other, and the sealing working volume increases, forming a partial vacuum, so the liquid in the fuel tank Driven by atmospheric pressure, it enters the oil suction chamber; at the same time, the gear teeth of the oil discharge chamber enter into engagement in sequence, and the sealing working volume is reduced, so the left side oil is squeezed out and sent to the pressure pipeline. When the gear rotates continuously, there are continuous gear teeth exiting meshing on the right side and entering meshing on the left side, so the gear pump can continuously suck and discharge oil.