![[[smallImgAlt]]](/uploads/202337657/azpf-12-022rnt20mb-gear-pumps-azpf-azpffa3f9eaa6-5d7d-4109-8e05-4ec95e740750.png)
The concept of a gear pump is very simple, that is, its basic form is that two gears of the same size are in a tightly fitted housing that interacts with each other
Meshing and rotating, the inside of the housing is similar to an "8" shape, two gears are installed inside, and the outer diameter and both sides of the gear are closely matched with the housing. The material from the extruder enters the middle of two gears at the suction port and fills this space. As the teeth rotate, it moves along the shell and is discharged when the two teeth mesh.
In terminology, a gear pump is also known as a positive displacement device, which is like a piston in a cylinder barrel. When one tooth enters the fluid space of the other tooth, the liquid is mechanically squeezed out. "Because liquid is incompressible, liquid and teeth cannot occupy the same space at the same time, and thus the liquid is excluded.". Due to the continuous engagement of the teeth, this phenomenon continues to occur, providing a continuous discharge amount at the pump outlet. The discharge amount is the same for each revolution of the pump. As the drive shaft rotates continuously, the pump continuously discharges fluid. The flow rate of the pump is directly related to the rotational speed of the pump.
In fact, there is a small amount of fluid loss in the pump, which makes it impossible to achieve the operating efficiency of the pump. Because these fluids are used to lubricate both sides of the bearings and gears, and the pump body can never fit without clearance, it is impossible to discharge fluid from the outlet, so a small amount of fluid loss is inevitable. However, the pump can still operate well, achieving an efficiency of 93% to 98% for most extruded materials.
