What are the reasons and solutions for difficulty and overload in starting the dust removal motor?

In industrial dust control systems, stable start-up and normal operation of dust removal motors are key to ensuring production continuity and preventing safety hazards. In the actual production process, many enterprises may encounter problems such as difficulty in starting and overloading of dust removal motors, which not only affect the effectiveness of dust control, but may also lead to motor burnout, production shutdown, and other situations, increasing the operation and maintenance costs and safety risks of the enterprise.

The difficulty in starting the dust removal motor is mainly manifested by slow speed during startup, inability to start normally, or immediate shutdown after startup. The main reasons are concentrated in four aspects: power supply, motor itself, mechanical transmission, and control equipment, which need to be investigated and accurately located one by one. Power supply issues are one of the most common causes. If the supply voltage is lower than 10% of the rated voltage of the motor, it will result in insufficient starting torque of the motor, which will prevent the load from starting normally; At the same time, power cord diameter that is too thin, poor line contact, or three-phase power supply phase loss can also cause abnormal current during startup, leading to difficulty in starting. A certain chemical enterprise once experienced frequent startup failures of dust removal motors. After investigation, it was found that due to aging power supply lines and insufficient wire diameter in the workshop, the voltage dropped to 85% of the rated value during startup. After replacing the cable with the appropriate wire diameter and repairing the circuit, the startup failure was completely resolved.

Malfunctions in the motor itself can also cause difficulties in starting. The insulation aging, short circuit or open circuit of the motor winding will cause an abnormal increase in starting current, making it impossible to start normally. At this time, the insulation resistance needs to be measured with a megohmmeter. If the insulation resistance is lower than 0.5M Ω (rated voltage below 1000V), the winding needs to be repaired in a timely manner; Broken rotor bars, stuck bearings, or poor lubrication can increase the starting resistance of the motor, resulting in slow or even impossible starting. It is necessary to regularly check the bearing status and add suitable lubricating grease in a timely manner. If rotor faults are found, professional personnel should be responsible for maintenance. In addition, motor wiring errors, such as confusion between star and delta connections, can also lead to insufficient starting torque and difficulty in starting. It is necessary to strictly follow the motor nameplate requirements for standardized wiring.

Mechanical transmission and abnormal load can also affect motor starting. The connection between the dust removal fan and the motor is eccentric, and the coupling is loose or stuck, which will increase the starting load and cause difficulty in starting the motor; Excessive dust accumulation or blockage of the fan impeller, or blockage of the dust removal pipeline, can cause the motor to experience excessive resistance during startup and fail to start normally. During the start-up of a dust removal motor in a certain building materials enterprise, there was a "stuck car" phenomenon. After disassembly, it was found that the fan impeller had accumulated dust for a long time, resulting in excessive rotational resistance. After cleaning the dust accumulation on the impeller and checking the smoothness of the pipeline, the motor resumed normal start-up. Malfunctions in control equipment cannot be ignored. Contact erosion or damage in contactors and relays, or improper parameter settings in frequency converters, can cause abnormal motor start signals and prevent normal startup. Regular maintenance of control equipment is necessary to optimize frequency converter parameters.

Compared to the difficulty of starting, the harm of overloading the dust removal motor is greater. Long term overloading can cause the motor winding to overheat, insulation to age, and even burn out the motor. The main reasons are divided into four categories: heavy load, abnormal motor itself, power supply fluctuations, and improper operation and maintenance. Overloading is the main reason. Excessive air flow in the dust removal system, increased pipeline resistance, or dust accumulation and debris blockage in the fan impeller can cause the motor to operate at overload for a long time, resulting in current exceeding the rated value; Some companies blindly increase the dust removal load, resulting in a mismatch between motor power and actual load, which can also cause overload. A certain mining enterprise once experienced a blockage in the dust removal pipeline, causing the current of the dust removal motor to continuously exceed 120% of the rated value. After long-term operation, the motor winding burned out. After cleaning the pipeline and optimizing the load, the overload problem was solved.

Abnormal operation of the motor itself can lead to overload. Short circuit and leakage of motor windings can cause abnormal increase in operating current, leading to overload; Bearing wear and jamming can increase mechanical friction resistance, leading to an increase in motor load; Friction between the motor rotor and stator can also increase operational resistance and cause overload. Power supply fluctuations can also induce overload. Unstable power supply voltage and unbalanced three-phase voltage can cause fluctuations in motor operating current, and long-term abnormal range can lead to overload. Enterprises can avoid overloading caused by power supply problems by installing voltage stabilizers and regularly checking power supply lines. In addition, improper operation and maintenance can also increase the risk of overload, such as not regularly cleaning up motor dust accumulation, blocking heat dissipation channels, resulting in poor motor heat dissipation, decreased operating efficiency, and indirectly causing overload; Adding too much or too little lubricating grease can increase mechanical wear and also lead to an increase in load.

To address the difficulties in starting and overloading the dust removal motor, it is necessary to follow the principle of "first investigate, then handle, and then review", take targeted measures, and ensure the effectiveness of the treatment without leaving any safety hazards. When dealing with startup difficulties, the first step is to check the power supply, measure the supply voltage, investigate the contact condition of the circuit, ensure stable voltage, smooth circuit, and no phase loss in the three-phase power supply; Next, inspect the motor itself, measure insulation resistance, check the condition of bearings and windings, and promptly repair faulty components; Recheck the mechanical transmission and load, adjust the concentricity of the coupling, clean the dust accumulation on the impeller and pipeline blockage, and ensure that the load is normal; Finally, inspect the control equipment, repair the contactors and relays, and optimize the parameters of the frequency converter.

When dealing with overload issues during operation, it is necessary to first reduce the motor load, such as adjusting the air volume of the dust removal system, cleaning the dust accumulation in the pipeline and impeller, to ensure that the load matches the motor power; Secondly, troubleshoot the motor itself, repair components such as windings and bearings, and restore normal motor performance; Stabilize the power supply quality again, install voltage regulators, and regularly inspect the power supply lines; Finally, strengthen daily operation and maintenance, regularly clean the motor dust, check the heat dissipation situation, standardize the addition of lubricating grease, and avoid overloading caused by improper operation and maintenance. After processing, it is necessary to conduct no-load and load test runs, observe the motor operating parameters, and confirm that there are no abnormalities before putting it into normal use.

Industry experts remind that difficulties in starting and overloading dust removal motors are mainly caused by improper daily operation and parameter matching. Enterprises should establish a normalized operation and maintenance mechanism, regularly conduct comprehensive inspections of motors, control equipment, and dust removal systems, and promptly identify potential hazards; At the same time, strengthen the professional training of operators, enhance their ability to troubleshoot and handle faults, and avoid blind operation that may lead to the expansion of faults. In addition, enterprises should choose motor models reasonably according to the on-site working conditions, avoid load and motor power mismatch, and reduce the occurrence of faults from the source.

Next, relevant industries will further sort out common faults and handling standards of dust removal motors, promote replicable operation and maintenance experience, help enterprises improve equipment management level, reduce downtime due to faults, lower operation and maintenance costs, ensure stable operation of dust removal motors, and build a solid guarantee for industrial dust treatment and safety production.