First, common problems and their causes
1. The geared motor generates heat and oil leakage. In order to improve efficiency, worm geared motors generally use non-ferrous metals as worm gears, while worms use harder steel. Because it is a sliding friction transmission, more heat is generated during operation, which causes a difference in thermal expansion between the various parts of the reducer and the seal, thereby forming a gap in each mating surface, and the lubricating oil is thinned due to an increase in temperature, which is likely to cause leakage. . There are four main reasons for this situation. One is that the material is not properly matched; the other is the poor quality of the surface of the friction surface; the third is that the amount of lubricant added is not correct; the fourth is the poor assembly quality and environment.
2. Worm gear wear. The worm gear is generally made of tin bronze. The paired worm material is hardened to 45°C to HRC4555, or 40Cr hardened to HRC5055 and then ground to a roughness of Ra0.8μm by a worm grinder. The geared motor wears very slowly during normal operation, and some geared motors can be used for more than 10 years. If the wear speed is fast, it is necessary to consider whether the selection is correct, whether it is overloaded, and the material, assembly quality or use environment of the worm gear motor.
3. Drive small helical gear wear. It usually occurs on a vertical mounted reducer, mainly related to the amount of lubricant added and the type of oil. When the vertical installation is installed, it is easy to cause insufficient lubricant. When the reducer stops running, the transmission gear oil between the motor and the reduction motor is lost, and the gear is not protected by the lubrication. When the geared motor starts, the gear is mechanically worn or even damaged due to the lack of effective lubrication.
4. The bearing of the worm gear motor is damaged. In the event of a fault, even if the gearbox is well sealed, it is often found that the gear oil in the geared motor is emulsified and the bearing is rusted, corroded and damaged. This is because after the geared motor runs for a period of time, the condensed water produced by the increase in the temperature of the gear oil and after cooling is mixed with water. Of course, it is also closely related to bearing quality and assembly process.
Second, the solution
1. Guarantee the quality of assembly. You can purchase or make some special tools. When disassembling and installing the parts of the reducer, try to avoid hitting with other tools such as hammers. When replacing gears and worm gears, try to use original parts and replace them in pairs. When assembling the output shaft, Pay attention to the tolerance fit; use a release agent or red dan oil to protect the hollow shaft to prevent wear and rust or to match the area scale, which is difficult to disassemble during maintenance.
2. Selection of lubricants and additives. The worm gear reducer generally uses 220# gear oil. For heavy-duty motors with heavy load, frequent start and poor use environment, some lubricating oil additives can be used to make the gear oil still adhere to the gear surface when the reducer stops running, forming protection. Membrane to prevent heavy load, low speed, high torque and direct contact between metals at start-up. The additive contains a seal regulator and a leak preventer to keep the seal soft and elastic, effectively reducing oil leakage.
3. Selection of the installation position of the geared motor. When possible, do not use a vertical installation. When installing vertically, the amount of lubricating oil added is much more than that of horizontal installation, which may cause heat generation and oil leakage of the reducer.
4. Establish a lubrication maintenance system. The geared motor can be maintained according to the “five-definite” principle of lubrication work, so that every reducer has a responsible person to check regularly and find that the temperature rise is obvious. If the temperature exceeds 40 °C or the oil temperature exceeds 80 °C, the quality of the oil drops or oil. When more copper powder is found and abnormal noise is generated, stop using it immediately, repair it in time, troubleshoot it, and replace the oil. When refueling, pay attention to the amount of oil to ensure that the geared motor is properly lubricated.
