Causes and Preventive Measures for Vibration Screen Motor Burnout in High-Temperature Weather

During the operation of the vibrating screen, motor burnout often occurs, especially in high-temperature weather in summer. What causes this phenomenon? How to effectively prevent it?

1、Loosening of anchor bolts

Loosening of anchor bolts is one of the main faults causing the burnout of vibration motors. Due to its special structure, the eccentric blocks at both ends of the vibration motor, which generate exciting force, are driven by the motor to impact the anchor bolts hundreds or even thousands of times per minute. Under the action of huge exciting force, it is very easy to cause the loosening of the motor's anchor bolts. The loosening of one anchor bolt will soon cause the loosening of other bolts. If not found in time, it will lead to the fracture of the anchor bolts and the burnout of the motor.

Preventive measures:

（1）Use high-strength bolts. The strength of anchor mounting or flange mounting bolts shall not be lower than grade 8.8;

（2）Frequently reinforce the anchor bolts. The anchor bolts of the motor shall be tightened for many times in the initial stage of operation;

（3）Add anti-loosening devices. An elastic washer must be added under each nut, and double nuts shall be used for fastening if necessary;

（4）The foot surface of the motor shall be in good contact with the base plate, and all anchor bolts shall be evenly stressed.

2、Installation issues

When installing a vibration motor, it must be firm and reliable. When two vibration motors need to be installed symmetrically, their positions on both sides of the equipment must be completely symmetrical, and resonance of the equipment should be avoided. Since the vibration motor is equipped with eccentric blocks at both ends to adjust the amplitude, if inclined or vertical installation is required on site, the axial direction of the motor bearing will bear all or part of the gravity of the eccentric blocks. If there is no special device such as a plane bearing in the vibration motor for protection, it will cause great damage to the bearing over time, thereby shortening the service life of the motor.

Preventive measures:

（1）The vibrating machinery is required to be free from jamming. The supporting points should be connected with springs, the connection with other equipment should be flexible, and there should be no rigid contact with the external environment and equipment;

（2）Try to avoid vertical or inclined installation;

（3）Choose vertical vibration motors with additional plane bearings inside.

3、Asymmetric adjustment of eccentric blocks

A vibration motor uses four fan-shaped eccentric blocks as excitation blocks, with two blocks at each end of the motor forming a group. The required excitation force, ranging from zero to maximum, can be achieved by adjusting the angle between the two eccentric blocks at the coaxial end of the vibration motor. When adjusting the eccentric blocks, if the directions of the two ends are reversed, a large spatial torque will be formed inside the vibration motor. Operating in such a state with a large torque for a long time will inevitably lead to motor burnout. Therefore, when adjusting the eccentric blocks, it is necessary to ensure that the angles of the eccentric blocks at both ends of the motor are consistent, without being in a state, and that they correspond to each other and are symmetrical. At the same time, the bolts fixing the eccentric blocks must be tightened, and the spring clips must be properly installed. Generally, there are two vibration motors on the left and right of the vibrating screen, and it is required that the phase sequence of the motors should correspond, and they must not operate in the same phase.

Preventive measures:

Only by strictly following the installation, use, and maintenance rules of the vibration motor can the vibration motor function better and prevent burnout accidents caused by asymmetric adjustment of eccentric blocks.

4、Poorly sealed protective cover

In actual work, vibration motors often operate in extremely harsh environments with heavy dust. If there are large gaps between the protective covers at both ends of the motor and the motor itself, dust can easily enter both ends of the motor, causing frictional movement between the eccentric blocks. This frictional movement, in turn, generates a large amount of heat, and when the heat accumulates to a certain extent, the motor will be burned out.

Preventive measures:

In harsh working environments, first, make every effort to ensure the tight sealing of the motor's protective cover; second, keep the interior of the protective cover clean and regularly remove accumulated dust.

5、Ambient temperature

During the operation of a vibration motor, if the temperature of the medium conveyed by the equipment is too high and the vibration motor is rigidly connected to the equipment, the temperatures of the vibration motor and its housing will rise rapidly due to the thermal conductivity of metal. In a confined space, poor heat dissipation will cause local overheating of the motor, leading to burnout.

Preventive measures:

（1）Take measures to reduce the temperature of the materials;

（2）Enhance ventilation and heat dissipation to lower the ambient temperature;

（3）Keep the motor as far away as possible from high-temperature media and materials under the premise of ensuring the normal operation of the equipment.

6、Poor heat dissipation

General motors are usually equipped with their own heat dissipation devices, typically a fan at one end. When the fan rotates, the generated wind flows rapidly along several vertical ribs on the casing. On one hand, it can quickly dissipate the heat generated by the motor; on the other hand, it can blow away the dust accumulated on the casing, keeping the motor in good working condition at all times.

Due to structural limitations, vibration motors cannot be equipped with cooling fans. When excessive dust accumulates on the motor surface, it will block heat dissipation, leading to rapid temperature rise inside the motor and eventual burnout.

Preventive measures:

（1）During motor design, consideration should be given to making its surface as smooth as possible. Otherwise, when dust accumulates to a certain extent in the heat dissipation ribs on the motor surface, it will cause the motor's heat dissipation to fail. In such cases, consideration should be given to reducing or even removing the surface heat dissipation ribs.

（2）Frequently remove dust from the motor surface to keep it working under good conditions.