In the actual motor production and manufacturing process, there are many factors that affect motor quality, including some implicit factors and explicit factors. However, since this hazard does not develop overnight, and the impact is also long-term, relevant staff need to start with the quality of the motor to improve the efficiency of electric energy application.
1. Hidden factors affecting motor quality
1.1 The rotor or rotor core should be heat-sleeved onto the shaft
In the production and manufacturing of motors, the main function of thermal sheathing equipment is to promote the integration of the rotor, thereby ensuring that the rotor of the motor reaches a certain strength. However, it can be seen in actual production that if the rotor generates slight heat, it will cause a large gap between the iron core and the rotating shaft, causing an imbalance in the air gap. In the vibration of the motor, the noise pollution is relatively large. However, these phenomena are not visible, so operators can easily ignore them.
1.2 The welding machine base must be aged thoroughly
Insufficient aging of the welding machine base is the main cause of deformation. Even if this phenomenon occurs, it will not cause any operational failure problems in a short period of time. Normally, it will be discovered within half a year. Therefore, the inspection work is relatively difficult. Specifically, the variation in coaxiality is also an important factor affecting motor vibration. The degree of damage to the bearing can be determined by the intensity and frequency of the noise.
1.3 Dip paint
The so-called dipping paint usually refers to the dipping paint of windings. This phenomenon is not very obvious in actual production and manufacturing. If the quality of the dipping paint is not up to standard, moisture will be absorbed and the insulation strength will be reduced. Moreover, the winding is not easy to dissipate heat. During long-term operation, the temperature will rise and the insulation equipment will be damaged.
1.4 Iron core
The efficiency of the motor is easily affected by the quality of the core, including power parameters, noise, and other factors. Poor quality of the iron core means that the pressure is too loose and the consumption of iron is relatively large. If the temperature continues to rise, burrs will cause serious harm to the insulation equipment and shorten the service life of the winding. In severe cases, a certain amount of electromagnetic noise will be produced, causing the motor to run out of balance.
1.5 Binding of formed winding ends
For the formed winding, its ends must be tightly tied, and an appropriate amount of space must be left. This is mainly to avoid damage to the winding when starting the motor and to ensure the highest heat dissipation efficiency.
1.6 Insert the rotor
During the operation of the motor, when rolling the bearings, it is necessary to install bearing end caps on both ends of the rotor to avoid damage to the bearings. Motors with appropriate electrodes do not allow excessive gaps. Therefore, relevant staff need to pay more attention to the rotor insertion of the motor.
1.7 Copper bar rotor welding
The welding requirements for copper bar rotors are relatively strict. Usually, they need to be carried out in a certain state, and the state cannot be changed, otherwise, a diamond shape will be formed.
1.8 Bearing assembly
When performing bearing assembly work, the most important thing is to maintain a clean assembly environment. Operators cannot wear gloves. If it is a sliding bearing, the staff needs to pay more attention. But if it is a rolling bearing, it needs to be coated with a layer of grease.
2. Ways to improve motor quality
The manufacturing work of motors mainly includes two aspects, the first is the manufacturing of parts, and the second is the assembly of parts. This is also the premise and foundation of motor assembly. During the manufacturing process, the main influencing factors on motor quality are as follows:
2.1 Iron core
The iron core is the main component of the motor, and there is a direct relationship between its quality and the installed pressure value.
First, when stamping, you need to pay attention to the size of all equipment, and you also need to ensure that its quality reaches standard levels. Try to avoid serious deformation of the core. In addition, it is also necessary to control the center hole, bearings, mobile pressure resistance, and other parts.
Second, the rotor can make full use of the punching groove to cut off the waste while ensuring the symmetry of the air gap.
Third, because the rotor must be twisted to reduce the noise caused by vibration, the best way is to change the angle every time when punching high-speed grooves. After all is completed, it will become a skewed state. However, it is also Notching machines that require many functions can also be equipped with a special key if the equipment is not good.
Fourth, when the lamination of the motor core stampings fails, the oblique key can also be used to position the lamination, so that it is more convenient to tilt the stator slot by one or more slot pitches. This design is very simple and easy to operate and can meet the design concept of the motor.
Fifth, pay attention to the material properties and the properties of three-pole stack riveting.
2.2 Cast aluminum rotor
The quality of the cast aluminum rotor will directly affect the performance and operation of the motor. The quality of some cast aluminum is determined based on the production technology. Most cast aluminum defects are due to incorrect operating methods or incorrect process parameters. There is something wrong with the structure of the mold. Generally, there are many types of defects, which can be solved in the following ways.
First, the way to eliminate the pores: try to eliminate the gas source and reduce the gas to a minimum; the exhaust system should be designed so that the mold can exhaust normally, and the air channel should be cleaned frequently to make it normal; reduce the speed of molding.
Second, ways to eliminate cold separation: increase the mold filling speed to allow smooth air flow during the die-casting process; and control the temperature during the manufacturing process.
Third, ways to eliminate cracks: redesign the gating system to improve the design of the casting, make the wall thickness as consistent as possible, and design the wall corners into rounded corners; remove the gate and try not to let the casting experience too much impact; the operation process Be standardized.
Fourth, ways to eliminate deformation and marks: make the design of the mold structure and castings more reasonable; choose a better pouring system; inspect the mold regularly; and use better quality coatings.
2.3 Mechanical processing and assembly
Machining will affect the performance of the motor, not only the operating performance but also the installation process. Mechanical processing must be strictly controlled in terms of size, shape, accuracy, etc. During assembly, the radial and axial accuracy of the motor must meet the requirements of assembly technology and process, especially before the final installation step, the rotor must be balanced.
2.4 Points to note to ensure performance
Strictly follow the design requirements to ensure the interference between the stator core and the frame, control the unbalance of the motor rotor, and on the basis of controlling the coaxiality of the stops at both ends of the frame, increase the inspection of the inner diameter of the stator core and check the deformation of the core after loading; control the chute degree of the cast aluminum rotor, and control the direction of the chute degree according to the design requirements.