Today, I will introduce five causes of double gear pump failures and how to solve them.

(1) The gear pump does not absorb oil or the flow rate is small

The main reasons for the gear pump not absorbing oil or the flow rate being small are:

①The oil suction position is too high or the oil level is insufficient;

②The radial gap between the inner addendum circle of the gear pump and the hole in the pump body is too large, and the gap between the side of the gear and the end faces of the front and rear cover plates is too large;

③ The gear pump is not tightly sealed;

④ The oil filter is blocked;

⑤ The oil temperature is too high.

(2) Insufficient pressure

The main reasons for lack of stress are:

① The radial clearance and axial clearance of the gear pump are too large, and the end face clearance has a greater influence;

②The tooth body has cracks or leakage;

③The oil viscosity is too high or the oil temperature is too high;

④Gear pump power does not match;

⑤ The oil filter is blocked;

⑥The pressure adjustment of the relief valve is too low or out of order.

(3) Excessive vibration and noise

The main causes of excessive vibration and noise are:

①Gear error or 2 gear axes are not parallel;

② The diameter of the oil inlet pipe of the gear pump is too small;

③ The oil filter is clogged, or the speed is too high;

④The two sides of the pump body and the cover are impacted by hard objects, the pump body and the pump cover are not vertically sealed, and air is sucked in when rotating;

⑤The axis is not concentric.

(4) Oil leakage

The main causes of oil leakage are:

① The pump cover and the sealing ring are too loose;

②Oil seal skeleton spring falls off;

③The sealing surface of the shaft is scratched.

(5) The gear pump does not operate normally or is seized

The main reasons for the abnormal operation of the gear pump or the phenomenon of seizure are:

① The axial clearance and radial clearance of the pump body are too small;

②Needle rotation is not flexible;

③The concentricity between the cover plate and the shaft is not enough;

④Pressure valve failure;

⑤ The concentricity of the coupling is not enough;

⑥Impurities in the pump.

For more information, please refer to: Hydraulic Gear Pump Manufacturer