(1) The fluid resistance inside the canned pump increases (increased load). Check the casing, impeller and induction wheel. When the surface is rough, use sandpaper or mechanical method to polish the surface.

    (2) The bearing contact surface is abnormal (increased mechanical loss). The bearings, bearings and thrust plates should be inspected and replaced to eliminate various factors that cause increased bearing friction.

    (3) Poor contact between the rotor and stator of the motor (increased mechanical loss). Check the motor stator and rotor surfaces for abnormal conditions such as expansion and deformation, and eliminate various factors that cause bearing wear.

    (4) The impeller of the shield pump is in poor contact with the pump casing. Check the installation of the pump shaft and impeller, and the degree of bending of the pump shaft. If the bending of the pump shaft does not meet the requirements, the new shaft should be corrected or replaced.

    (5) There is foreign matter in the canned motor pump casing. Canned pumps are mostly welded constructions. When welding is installed, welding slag may fall into the pump, and at the same time, debris in the lithium bromide solution will enter the pump, causing serious consequences. In this case, remove the pump casing and check for foreign objects in the pump.

    (6) The insulation resistance performance of the canned pump motor is reduced, and the three-phase coil resistance is unbalanced (electromechanical abnormality). First measure, correct or replace the insulation resistance and coil resistance of the motor. If the motor gets wet, use a torch to dry the motor slowly. When the insulation resistance and coil resistance cannot be restored, the motor stator must be replaced.

    (7) The motor is running out of phase. Check the tightness of the canned motor of the canned pump motor and tighten it if it is loose.

    (8) If the voltage and frequency of the power supply fluctuate, check the circuit power supply.