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Those who work on the maintenance of industrial equipment know well: when small components fail to perform properly, it is the entire production line that suffers the consequences. For large steel mills, every minute of downtime costs money. Industry estimates suggest that a steel plant incurs an additional cost of 680 yuan for every minute it is shut down. This means that a shutdown of 12 hours can result in losses of hundreds of thousands, or even millions, of yuan. And the cause of all this was merely an abnormal vibration in the device due to a non-replaced widget. On New Year’s Day 2023, the hammer crusher in the lime plant of that steel mill experienced abnormal vibration. Upon on-site inspection, the engineers found that the bearing’s inner ring had already started to wear out; due to the lack of timely replacement, wear on one side of the bearing area had reached 2.5 mm. The viscosity of the lubricant had decreased, there were impurities present, and the sealing material had undergone thermal aging. Traditional rubber seals harden and become ineffective at high temperatures, leading to wear on the shaft. If this situation continues, not only will the equipment come to a complete stop, but other critical components may also be damaged. The steel plant had only a 12-hour maintenance window; fortunately, the engineers managed to complete the emergency repairs in just 6 hours, managing to preserve most of its production capacity. Nevertheless, the cost of this sudden shutdown plus emergency repairs remains a significant expense. The bearing sealing in crushers faces multiple challenges; the failure of traditional sealing solutions is clearly evident in the aforementioned cases, and the underlying reasons can be summarized as follows: a high-concentration dust environment. When the crusher is in operation, it generates a large amount of fine dust, with particle sizes as small as the micron level. These dust particles are highly penetrative and can easily enter the bearing chamber through ordinary sealing gaps, where they mix with lubricant to form an abrasive paste that accelerates the wear of the bearing races. Heavy loads and impact loads. The crusher is subjected to periodic impact loads, causing significant radial runout and axial movement of the main shaft, which places extremely high demands on the sealing elements’ ability to keep up and their adaptability to changes in clearance. Temperature rise and thermal expansion. During continuous operation, the bearing temperature can reach 70–100°C, which leads to a decrease in the viscosity of the lubricating oil and accelerates the aging and hardening of traditional rubber seals. Key innovative technologies for magnetic oil seals: 1. The O-ring of the moving ring is used in an interference fit to clamp the shaft, preventing wear on the shaft surface and eliminating energy consumption. 2. The product features a magnetic design; the magnetic force keeps the stationary and rotating rings in close contact, thereby achieving zero leakage. 3. High-carbon fiber, a wear-resistant material, is used as the friction pair between the stationary and rotating rings, resulting in a low coefficient of friction. 4. The product has a compact design and is installed at the crude oil seal position, requiring no modifications to the equipment. 5. The operating temperature can range from -30°C to 160°C; special applications can be designed separately. 6. The service life is over 25,000 hours. Fujian Huali Sealing Technology Co., Ltd. provides a solution: Modification plan – replace the original skeleton oil seal with a magnetic oil seal. Before implementation, a simple structural modification was made to the bearing outer ring cover, and the machining dimensions were determined based on the actual sizes of the rotating and stationary rings. The installation steps include: the field workers receive the oil seal as a single unit. During assembly, an appropriate amount of lubricant is applied to the sealing rings of the moving and stationary parts (to prevent damage to these rings). After installing the oil seal on the gland (with the moving ring facing the side where the medium is present), both the gland and the oil seal are installed in the chamber. This simple assembly process is suitable for use in most types of equipment. Transformation effect. After the modification, the equipment has been in operation for over half a year without any oil leaks; the bearings are well-lubricated, and equipment failures have significantly decreased. This practice has verified the excellent sealing performance of magnetic oil seals on equipment.