If the gear pump is not functioning properly or there is a phenomenon of seizure This situation more common in the needle rotation is not flexible Pump body axial clearance and radial clearance is too small Cover and shaft concentricity is not enough Pump and motor coupling Insufficient concentricity, pressure valve failure, gear pump impurities. Treatment methods such as: Adjust the concentricity of the pump shaft and motor coupling so that it does not exceed 0.01mm. Replace the cover to concentric with the shaft. Fine silk mesh filter oil decontamination. This situation is generally common in the gear pump tip circle and the pump body bore radial clearance is too large, gear side and front and rear cover end clearance is too large and so on. Suction position is too high or the oil level is insufficient or the filter is clogged, the gear pump seal is not tight, the oil temperature is too high, etc., may also lead to non-oil absorption and other conditions. Treatment methods such as: replacement gear pump body. In the tank to fill the oil, reducing the suction position. Clean or replace the filter element. Replace the sealing element, fastening the connector. Add a cooler in the tank or air-cooled.