Self-priming capability generally means that the pump does not need to be pre-filled with liquid in the pump body when it starts, but is able to suck in the liquid under its own action. Whereas, a gear pump is a pump that transports liquids through the meshing of gears, and its working principle is to use the rotation of gears to generate pressure and flow.
The gear pump is mainly composed of a pair of intermeshing gears, pump body, front and rear pump covers and shafts. During operation, the rotation of the gear causes the tooth space to alternately form a sealed suction and discharge chamber, so as to realize the suction and discharge of liquids.
Due to the structure and working principle of the gear pump, it does not have the ability to self-prime. Gear pumps need to be pre-filled with liquid to start, and starting without liquid can lead to damage to the pump. For applications that require self-priming capability, such as certain processes in the chemical, pharmaceutical, food and other industries, gear pumps are not suitable.
Gear pumps are not self-priming. Its structure and principle dictate that it needs to be pre-filled with liquid in order to work properly. For applications that require self-priming capability, other types of pumps with self-priming capability should be selected, such as diaphragm pumps, pneumatic diaphragm pumps, or progressive cavity pumps.
In order to solve the problem of insufficient self-priming capacity of gear pump, some technical means can be adopted: a vacuum device is set at the inlet of the pump, and the liquid is sucked into the pump by vacuum; Alternatively, a return valve can be installed at the outlet of the pump so that the pump can automatically reflow to fill the pump body when it is started.