Preparation of highly stable magnetic fluid and analysis of dynamic sealing characteristics of large-diameter eccentric shafts

A highly stable magnetic fluid with high saturation magnetization is created, and a dynamic magnetic fluid sealing device for large shaft diameters is designed. This device features a sealing diameter of 380 mm and a sealing gap of 0.5 mm. The study evaluates the temperature rise rate, sealing capability, and long-term sealing performance under various conditions, including the magnetic fluid's saturation magnetization, linear velocity, sealing gap, and pole tooth width. The structural parameters of the dynamic magnetic fluid seal device are optimized, resulting in a dynamic seal that can operate sustainably under conditions of a maximum shaft deflection of 0.25 mm, a maximum linear velocity of 23.8 m/s, and a sealing vacuum of 1300 Pa.