Common faults and their causes of gear pumps (1)       

1, the pump can not produce oil

If the gear pump is not found in the commissioning of the engine, first check the rotation direction of the gear pump is correct. Gear pump has the left and right points, if the direction of rotation is not right, the pressure generated by the internal gear meshing volume difference will make the oil seal being washed and oil leakage. Second, check the gear pump inlet port of the oil filter is blocked, such as plugging, will cause oil absorption difficult or can not suck oil, and the oil suction hose is sucked flat phenomenon.

2, the oil seal was rushed out

(1) the direction of gear pump is not right. When the rotary direction of the pump is not correct, the high pressure oil will go directly to the oil seal. Because the general low pressure framework oil seal can only withstand the pressure of 0.5MPa, it will make the oil seal being rushed out.

(2) the axis of the gear pump bears the axial force. The axial force is often related to the tight coupling between the end of the gear pump shaft and the shaft sleeve. That is to say, when the pump is installed, the hammer is hard to be smashed or the shaft pump is forced to press into the sleeve by installing the screw. This causes the pump shaft to be subjected to a backward axial force, and when the pump shaft rotates, this backward axial force will force the pump to wear more rapidly. Because of the internal gear pump is sealed by the gear face and the sleeve end fitting, when the axial seal wear serious, pump internal axial seal will produce a certain gap, resulting in high and low pressure oil chamber and the oil seal out of communication. In this case the truck industry appears more. Is the main host on the sleeve caused by non-standard size.

(3) the gear pump bears too large radial force. If the gear pump installation of coaxiality is not good, will make the pump by the radial force beyond the limit of the oil seal, will cause oil seal leakage. At the same time, it will cause the pump internal floating bearing damage.