In the daily work of electricians, maintenance and repair of electric motors are important tasks. Among them, the repair of sliding bearings is particularly critical, and lead pouring is a common and effective repair method. Today, we will delve into how to pour lead to repair the sliding bearings of electric motors.
Preparation
Before carrying out the lead pouring operation, sufficient preparation must be made. Firstly, it is necessary to prepare the necessary tools, such as lead melting furnaces, casting spoons, molds, etc. The lead melting furnace is used to heat and melt lead ingots, while the casting spoon is used to scoop up the melted lead liquid and pour it into the mold. The size and shape of the mold should be precisely matched with the repaired part of the sliding bearing to ensure that the cast lead layer can fit tightly.
At the same time, sufficient lead ingots should be prepared. The purity of lead should comply with relevant standards. Generally speaking, the higher the purity, the better the quality of the lead layer after casting. In addition, auxiliary tools such as sandpaper and cleaning agents should be prepared to clean and polish the surface of the sliding bearing before pouring lead.
Pre treatment of sliding bearings
After receiving the sliding bearing that needs to be repaired, carefully clean its surface with a cleaning agent to remove oil stains, impurities, etc. These dirt will affect the bonding strength between the lead layer and the bearing, so they must be thoroughly removed. After cleaning, use sandpaper to polish the lead pouring area of the sliding bearing. The purpose of polishing is to roughen the surface and increase the adhesion between the lead layer and the bearing. When polishing, pay attention to uniform force to ensure that the entire surface to be repaired is polished to the required level and the roughness meets the requirements.
Lead pouring process
Install the prepared mold on the repaired part of the sliding bearing and fix it firmly. Then, place the lead ingot into the lead melting furnace and heat it up. During the heating process, close attention should be paid to the temperature of the lead melting furnace. The melting point of lead is relatively low, usually around 327 ℃. When the lead ingot is completely melted and the temperature reaches the appropriate range (usually slightly above the melting point), casting can be carried out.
Scoop the melted lead liquid with a casting spoon and slowly and steadily pour it into the mold. During the casting process, it is necessary to maintain a uniform flow rate of the lead liquid to avoid the occurrence of bubbles or interruptions. At the same time, it is necessary to ensure that the lead liquid in the mold is fully filled until the required thickness is reached. After the casting is completed, do not immediately move the sliding bearing, let the lead layer cool and solidify in its natural state.
Subsequent processing
After the lead layer has completely cooled and solidified, carefully remove the mold. At this time, there may be some unevenness in the lead layer cast on the sliding bearing, which needs to be repaired using tools such as files and sandpaper. By careful trimming, the surface of the lead layer is made smooth, with a natural transition to other parts of the sliding bearing, and meets the dimensional accuracy requirements of the sliding bearing.
After the repair is completed, clean the sliding bearing again to remove debris and other impurities generated during the repair process. Finally, quality inspection should be carried out on the repaired sliding bearings, such as checking whether the lead layer is firmly bonded to the bearing, and whether the smoothness of the sliding surface meets the standards. Only sliding bearings that have passed strict testing can be reinstalled for use in electric motors.
Pouring lead to repair the sliding bearings of an electric motor is a task that requires patience and skill. Every step is crucial, and only by strictly following the operating procedures can we ensure that the repaired sliding bearings can work properly and extend the service life of the motor. I hope today's sharing can give everyone a deeper understanding of this electrical skill.
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