What are the Advantages of Rotary Gear Pumps

Definition

A rotary gear pump belongs to the volumetric rotary pump, which has more than two internal gears that generate vacuum pressure by the mechanical movement of the gears, with the purpose of driving the movement of the fluid inside the pump. Rotary gear pumps are also called positive displacement devices, like a piston in a cylinder, when a gear enters the fluid space of another gear, because the fluid is incompressible, the fluid and the gear cannot occupy the same space at the same time, and in the process the fluid is mechanically squeezed and discharged. Due to the continuous engagement of the teeth, this phenomenon continue frequently. Therefore it also provide a continuous exclusion in the pump outlet. The pump once revolution, the amount of discharge is the same. With the uninterrupted rotation of the drive shaft, the pump is also uninterrupted discharge of fluid. Their discharge pressure can be very high, depending on many factors. Although gear pumps are most commonly used to transport water, they are not limited to this, as their outstanding characteristics are used to transport viscous and corrosive fluids. The fluids they transport include not only water, but also corrosive and viscous fluids, so a rotary gear pump can be used in a wide range of industries, such as the chemical and petroleum industries. That's why gear pumps are a popular choice in many applications. It is the best pump for hydraulic pump applications. Next let's see what are the main advantages of gear pumps?

Simple and compact structure

The most basic form of gear pump is two gears of the same size rotating in a closely matched shell. The interior of this shell is similar to the "8" shape, and two gears are installed inside. The outer diameter of the gears and the two sides of the shell are closely matched. The internal motor is compact, small in size and light in weight. It consists of aluminum alloy front cover, intermediate and back cover, alloy steel gears and aluminum alloy pressure plate, etc. Two DU bearings are installed in the front and back cover. Meanwhile, the gear pump is equipped with a differential pressure safety valve as overload protection, and the full return pressure of the safety valve is 1.5 times of the rated discharge pressure of the pump. It can also be adjusted within the range of allowable discharge pressure according to actual needs. The pump shaft end seal is designed in two forms. One is mechanical seal and the other is packing seal, which can be determined according to the specific use and user requirements.

Strong self-priming force, large speed range

The material from the extruder enters the middle of the two gears at the suction port and fills this space, moving along the casing as the teeth rotate and finally discharging when the two teeth mesh. In fact, there is a very little fluid loss in the pump, because these fluids are used to lubricate the bearings and both sides of the gears, and the pump body is never be free of clearance fit. So the fluid can’t be 100% discharged from the outlet, a small amount of fluid loss is inevitable, which makes the pump operating efficiency can’t reach 100%. But the rotary gear pump can still operate well, for most extruded materials, can still reach 93% to 98% efficiency. The flow rate of the pump is directly related to the pump speed. The general flow range is 0.045-30ms/h, and the pressure range is 0.7-20MPa, and the working speed is 1200-4000r/min.

Suitable for highly viscous fluids

Rotary gear pumps can be used for viscous and aggressive fluids. Gear pumps can handle fluids that are too viscous for centrifugal pumps. It is mainly used to transport various oils that are non-corrosive, free of solid particles and have lubricating ability .The fluids temperatures generally are not exceeding 70 °C, such as lubricating oil, edible vegetable oil, etc.

Easy maintenance and reliable work

Since the gear pump does not have to generate centrifugal force, it can run at a lower speed, which makes it smoother and easier to control. The pumping action is very controllable and mathematical: if you double the speed, you double the output. The output of a geared pump is independent of the discharge pressure. The pressure plate in the motor of the gear pump is the main element of radial and axial pressure compensation, which can reduce the bearing load and automatically adjust the axial clearance of the gear pump, thus effectively improving the performance index and working reliability of the gear pump; GM5, GPC4 series gear motor can provide single rotation without front bearing, double rotation without front bearing and single rotation with front bearing, double rotation with front bearing four types of structure. Among them, the gear motor with front bearing can withstand radial force and axial force.