Selection principle of gear pump in hydraulic system
When selecting and using gear pumps and gear motors, the indicators of various technical performance parameters should be strictly controlled within the range specified in the catalog or instruction manual. Let's take a look at the selection principles of gear pumps!
a. The speed of the gear pump is selected according to the speed of the prime mover. The normal operating speed must be lower than or equal to the rated speed of the gear pump. The short-term peak speed of the gear pump must not exceed the maximum speed specified in the sample. For the sliding bearing, it will be burned due to excessive speed.
b. According to the rotation direction of the prime mover, select the gear pump that matches its rotation. The direction of rotation of the gear pump is determined when it leaves the factory, and it is marked with a lead seal, and the user is not allowed to disassemble and change it.
c. Choose the displacement of the gear pump according to the required flow and the speed of the prime mover. Since the gear pump is a quantitative pump, an excessive flow will not only cause unnecessary loss of power, but also cause the system to heat up and cause failure. Therefore, when determining the flow, in addition to the working flow of the system, the leakage loss of other hydraulic components should also be fully considered, and the normal operation of the system will not be affected when the volumetric efficiency of the gear pump is worn out. This contradiction is particularly prominent when selecting a small displacement gear pump.
d. The normal working pressure of the system should be less than or equal to the rated pressure of the gear pump, and the short-term peak pressure should not exceed the maximum pressure. Reasonable selection of the working pressure of the gear pump is one of the most important factors to determine the life of the oil pump, because the life of the gear pump depends on the life of the bearing, and the life of the bearing is short if the load is large, especially for the gear pump with a sliding bearing structure. Pa, high pressure 21~31.5 MPa) choose the appropriate pump.
e. The anti-pollution ability of the gear pump depends on the structure of the gear pump. If it is a gear pump with fixed lateral clearance and rolling bearings, an oil filter with low filtration accuracy can be selected, and the gear with direction or radial clearance compensation and sliding bearing structure can be used. The pump is highly sensitive to pollution, and an oil filter with high filtration precision should be selected, and it should be implemented according to the requirements of the sample.
