Cooling tower motor Cooling tower In practical work, vibration problems are common, and their causes are complex. In order to solve the cooling tower motor failure, we need to go deep into the equipment and learn about the cause of its vibration. During the maintenance process, we summarized the main reasons for the large axial vibration of the motor. 
There are three main causes of vibration in cooling tower motors.
1. The pulsation of the electromagnetic call power supply: when the three-phase voltage is out of balance, the cooling tower motor struggles in the dilemma of lack of phase. It's like a dancer on stage losing his lights and staggering. The whispers of the stator: the core becomes elliptical, eccentric, loose, the windings are damaged, the ground is broken down, the turn is shorted, the wiring is wrong. These factors are like a group of invisible claws, making the three-phase current of the cooling tower motor unbalanced, like a lonely boat in a storm, swaying. The song of the rotor: the iron core is oval, eccentric, loose, and the rotor short-circuit ring and cage bar are welded or damaged, like an invisible saw, cutting the peace of the motor at all times. The unbalanced three-phase windings of the winding rotor, broken windings, ground breakdown, turn-to-turn breakdown, miswiring and poor brush contact are like the devil that troubles the motor and makes it struggle in pain. Second, the mechanical sigh cooling tower motor itself: the rotor is unbalanced, eccentric, loose, the air gap between the stator and the rotor is uneven, and the magnetic center is inconsistent. They are like notes on a musical score, and when they are out of place, the whole movement becomes disorganized. The tragedy of bearings: poor foundation installation, insufficient mechanical strength, resonance, loose fixing screws, these are like a **, quietly destroying the stability of the motor. As the bearing nears the end of its useful life, the vibration of the cooling tower motor gradually increases, noise is generated, and the grinding of the bearing and the fluttering of the lid are like the final elegy, announcing the end of the motor. Call of the coupling: Damaged coupling, poor connection, inaccurate alignment, mechanical unbalance of the load resonance of the system. These factors are like invisible spells, so that the motor can not get rid of the painful entanglement. 3. The vibration of the electromechanical chorus cooling tower motor often comes from the uneven air gap, which will cause unidirectional electromagnetic tension, further aggravate the unevenness of the air gap, and form a vibration chorus of electromechanical mixture. The axial series motion of the motor, the electromagnetic tension caused by the gravity of the rotor itself or the height of the installation, and the magnetic core of the magnetic force are like conductors in the orchestra, leading the rhythm of electromechanical vibration. This leads to an increase in the vibration of the motor, severe wear of the bearing bushing, and a rapid increase in temperature, like a poignant elegy that announces the end of the motor. 
2. Analysis of the causes of cooling tower failure.
1. Before the cooling tower motor stops, check the vibration of each part with a vibration meter, and conduct a detailed vibration value test on the parts with larger vibration according to the three aspects of vertical and horizontal axis. If the set screw or bearing end cap screw is loose, it can be tightened directly and the vibration can be measured to see if it is eliminated or reduced.
Second, check the three-phase power supply: whether the voltage is balanced or out of phase. Phase-out operation of cooling tower motors not only causes vibrations, but also causes cooling tower motors to heat up quickly. Observe if the pointer of the power meter swings back and forth, the current swing occurs when the rotor is damaged, and finally check if the three-phase current of the cooling tower motor is balanced, and stop if you find any problems with the machine**.
2. If the vibration of the cooling tower motor cannot be eliminated after dealing with the surface phenomenon, the power supply must be disconnected and the coupling must be disconnected. If the cooling tower motor vibrates in a dry test, it is an indication that there is a problem with the cooling tower motor itself. In addition, the power-off method can be used to distinguish between electrical and mechanical causes. When the power is cut off, the cooling tower motor does not vibrate immediately or reduce vibration, which indicates a cooling tower motor or electrical fault.
1. Maintenance for electrical reasons: first determine whether the three-phase DC resistance of the stator is balanced. If it is unbalanced, it means that there is an open weld in the welded part of the stator connection. Disconnect the winding phases and check for short circuits between the windings, such as faults. Obviously, burn marks can be seen from the insulating surface, or the stator windings can be measured using an instrument. Once the turn-to-turn short circuit is confirmed, the electrical winding should be offline again.
2. Cooling tower motor cause maintenance: check whether the air gap is uniform, if the measured value exceeds the standard, readjust the air gap, check the bearing, if the measured clearance is unqualified, replace the bearing, check the deformation and looseness of the bearing. Iron cores and loose cores can be bonded and filled with epoxy adhesive, the shaft is inspected, the bent shaft is repaired, the position of the shaft is reworked or adjusted, and then the rotor is balanced tested.
3. The load cooling tower is checked normally, and there is no problem with the electricity itself. The fault is caused by the connection part. At this point, check that the basic level, inclination, strength, and center position of the cooling tower motor are correct. Whether the coupling is damaged and whether the shaft phase tolerance of the cooling tower motor meets the requirements.