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A magnetic oil seal is a new type of dynamic sealing device that uses the magnetic force of magnets to replace traditional spring lip seals, thereby enabling automatic compensation of the sealing surface. It is widely used in the sealing of rotating shafts in devices such as reducers, gearboxes, fans, motors, pumps, and those related to new energy sources. The magnetic oil seal addresses a long-standing sealing challenge in industrial history through modular magnetic compensation, new material sealing technology, and easy installation; it effectively solves the problems associated with shaft surface wear and short service life of traditional skeleton oil seals. Current situation of using traditional skeleton oil seals in high-speed rotating equipment: 1. Prone to leakage: the spring is too loose, resulting in weak clamping force and oil seepage. If the spring is too tight, the oil film is disrupted; dry friction generates heat, which ultimately damages the shaft surface and causes oil leakage. 2. Shaft surface requirements: The surface hardness should be maintained at HRC30-40; chromium plating on the surface is preferred. (There is shaft grinding phenomenon.) 3. The skeleton oil seal can only handle linear speeds of up to 5 m/s. 4. Service life: 500–2000 hours. 5. It is prone to absorbing external moisture, dust, and other particles, which affects the service life of the bearings and gears inside the chamber. In contrast, magnetic oil seals have achieved several breakthrough improvements: firstly, zero shaft wear at linear speeds of up to 15 m/s. When in operation, the magnetic oil seal does not come into direct contact or friction with the shaft surface; it has no requirements regarding the surface hardness of the shaft, nor does it cause wear to the shaft surface, thereby fundamentally avoiding the problem of grooves forming on the shaft caused by traditional seals. (Special high-speed Hali seals can also be customized.) Second, adaptive compensation. Magnetic force provides a continuous pressure for end-face sealing; the friction pair is made of high-carbon fiber, with a friction coefficient of only 0.02, and it can automatically compensate for gaps even after wear, whereas the sealing performance of traditional lip seals declines sharply after wear. Thirdly, stability over a wide temperature range. By using high-temperature non-demagnetizing permanent magnetic materials and heat-stable stainless steel, performance can be maintained stable within the range of -30°C to 180°C, effectively preventing a decline in sealing performance due to temperature effects. (Products from Huali Sealing can also be customized for use in special environments.) Fourthly, they offer long lifespan and require no maintenance. The service life of magnetic oil seals can reach up to 25,000 hours, which is far longer than that of traditional oil seals; this significantly reduces the frequency of equipment maintenance and the associated downtime losses. The key technical breakthrough in innovative magnetic oil seals for magnetic compensation systems lies in the use of modular magnetic compensation systems. Traditional mechanical seals rely on springs to provide the pressure for end-face sealing, but springs have inherent defects such as fatigue failure and uneven pressure distribution. The magnetic compensation system achieves uniform distribution of the sealing surface pressure as well as long-term stability, thanks to the constant magnetic force generated by permanent magnets. More importantly, this system features a fully floating seal surface design. The moving ring is fixed to the shaft by an O-ring in a floating manner, and it can automatically adjust its position under magnetic force to maintain an optimal fit with the stationary ring. This design not only enables the device to accommodate larger shaft play but also significantly reduces the requirements for installation precision, enhancing the convenience of on-site installation.