The sealing relationship between magnetic oil seals and rotating equipment

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In factory workshops, equipment such as reducers, gearboxes, and fans operate around the clock, and one of the most troublesome issues is oil leakage. Once lubricant seeps out along the shaft, it not only leads to waste and environmental pollution; in cities with willow fluff, it may even pose a fire hazard. Moreover, a lack of lubricant can cause the bearings to grind dry, ultimately resulting in equipment damage. The traditional solution is to use a skeleton oil seal, but it acts like an eraser, constantly rubbing against the shaft surface; over time it inevitably wears out and ages, and oil leakage is only a matter of time. The emergence of magnetic oil seals has provided a completely new approach. It no longer relies on forced sealing, but instead uses magnetic compensation technology. Simply put, it consists of a pair of magnetic rotating rings and a stationary ring: the stationary ring remains fixed, while the rotating ring is mounted on the shaft and contains permanent magnets. Drawn together by magnetic force, the end faces of the moving ring and the stationary ring remain in close contact, creating a reliable sealing barrier to prevent oil leakage and the intrusion of external contaminants. This design brings several tangible benefits: first, it does not wear or damage the shaft. During operation of the equipment, the moving and stationary rings of the magnetic oil seal grip the shaft and the chamber through an interference fit with the O-ring, thereby avoiding friction with the equipment and eliminating shaft surface wear. Second, it has zero leakage and low friction. The stationary and rotating rings of the magnetic oil seal remain in close contact with each other due to magnetic force; the high-carbon fiber between them serves as the friction pair, with a friction coefficient of 0.02. Even if the sealing surfaces wear out over time, the magnetic force will push the rotating ring forward automatically, maintaining this close contact and thus ensuring that the sealing performance is not compromised. This is also the key to its ability to achieve near-zero leakage. Third is long lifespan and low power consumption. When the equipment is in operation, the magnetic oil seal has no impact on it, preventing unnecessary energy consumption by the equipment; as a result, the lifespan of this magnetic oil seal is much longer than that of traditional oil seals ； The friction pair inside the magnetic oil seal can effectively extend the product’s service life through prolonged use, with a service life of over 25,000 hours. Fourth, it is resistant to high temperatures and corrosion. Conventional products can operate within a temperature range of -30°C to 180°C. For special operating conditions, it is possible to customize the products or replace the materials used; for example, the main body can be made of brass, which helps prevent sparks from being generated by metal components due to collisions during operation. Fifth is to match the oil seal position. The product design of magnetic oil seals is compact; they are easy to install and can be installed manually. The magnetic oil seals can be installed without altering the existing cavity structure, which reduces the complexity of processing and assembling the equipment’s cavity. Today, from ordinary pumps and fans to the motors in new energy vehicles, magnetic oil seals are becoming an ideal alternative to traditional skeleton oil seals thanks to their reliable and durable properties, quietly preventing the lubricant in equipment from leaking.