Solution of entrap phenomenon of Gear Pump

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As for gear pump, in order to work smoothly, the gear meshing of the coincidence degree must be greater than 1, so there are always two pairs of gears mesh at the same time, and some of the oil is trapped between two pairs of teeth surrounded by a closed cavity.


The close cavity started to decrease gradually as the gears rotate, then gradually increase. Closed chamber will reduce, which will extrude the trapped oil and cause high pressure, and then the oil will be extruded from the gap, resulting in heating oil, which will cause extra load for the spare parts; While at the same time, the closed cavity volume increases and caused a partial vacuum, so that the gas dissolved in oil separation, which causes a sudden formation. All of these above will cause a strong vibration and big noise, this is called entrap phenomenon.


The harm

When the gear oil pump radial unbalanced force is large, the shaft will be bended, and the tooth top contact with the casing, which will accelerate the bearing wear and reduced the bearing life.


The method of eliminating

The common method to eliminate the entrap phenomenon is to open the unloading groove on both sides of the cover plate, so that the closed cavity volume decreases by unloading groove and pressure oil cavity discharge on the left, the volume increases by the right side of the unloading groove and communicated with the oil absorption cavity.


Honghai will explain more info of using gear pumps and the related instructions. Keep focusing on our news and we will update soon.


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