Analysis of the Reasons Why Slurry Pumps Always Trip

Electrical system problems

Motor overload: When the actual operating load of the slurry pump exceeds the rated load of the motor, an overload will occur. For example, if the slurry concentration is too high, the working resistance of the pump will increase; or the flow rate exceeds the design range of the pump, which will cause the motor current to continue to rise and exceed the rated value. When the overload reaches a certain level, protective devices such as thermal relays will operate, thereby tripping the switch to protect the motor from burning.

Electrical short circuit: Insulation damage to the motor winding is one of the common reasons. Long-term operation, moisture, aging and other factors may cause degradation of insulation performance, which in turn causes short circuits between the windings or between the windings and the shell. In addition, damaged cables and wiring errors in the junction box can also cause short circuit failures. During short circuit, the current will increase significantly instantly, triggering the short circuit protection, causing the slurry pump to trip.

Phase-loss operation: If a certain phase is broken in power, such as fuse fuse or contact contacts, it will cause phase-loss operation of the motor. When the phase is missing, the motor's magnetic field distribution is uneven and the torque is reduced. In order to maintain operation, the current will increase, causing overload protection tripping.

Mechanical failure problem

Impeller failure: The impeller is a key component of the slurry pump. If the impeller is stuck with debris or large particles in the slurry, or the impeller itself is worn or deformed, it will make the impeller inflexible rotation, increase the load on the motor, and in severe cases, it will cause tripping. In addition, the gap between the impeller and the pump housing is too small, and friction can also cause the motor to be overloaded and tripped.

Bearing damage: The bearing plays a role in supporting the pump shaft and ensuring the normal operation of the impeller. If the bearing is poorly lubricated, wears for a long time, or is invaded by impurities, it will cause damage to the bearing. After the bearing is damaged, the operating accuracy of the pump shaft decreases, resulting in vibration and additional resistance, which increases the motor load and causes tripping.

Other factors

Changes in media characteristics: The concentration, particle size, viscosity and other characteristics of the slurry may exceed the scope of application of the slurry pump.

Ambient temperature is too high: If the slurry pump is installed in a place with poor ventilation and high ambient temperature, it will be difficult for the motor to dissipate heat, which will lead to an increase in the motor temperature. When the temperature exceeds the allowable temperature rise of the motor, the performance of the motor will decrease and may even cause thermal protection tripping.