Abstract: Polar teeth on the rotating shaft and polar teeth on the pole pieces were two common magnetic fluid sealing structures; when discussing the influence of the position of polar teeth on the seal capacity and the position where the leak first occurs when the seal fails, a new type of magnetic fluid sealing structure, the opposite tooth structure, was proposed. The positions of the polar teeth of three magnetic fluid seal structures were all different. At first, the electromagnetic field simulation analysis of the three structure was carried out by using MAXWELL software. Then,the location where the leakage occurred first when the seal failed was found out, and the seal capacity of the three seal structures was compared. At last, the phenomenon of edge effect(the value of magnetic induction at the edge of the pole tooth is greater than the value of the magnetic induction at the center of the pole tooth) was discovered, and the reason and location of the edge effect were explored. The experimental results show that the seal structure with the pole teeth on the shaft has the smallest seal capacity, and leakage occurs first when the seal fails on the side close to the pole pieces; comparing with the seal structure where the pole teeth are on the rotating shaft, the seal capacity of the pole teeth on the pole pieces structure and the opposite tooth seal structure are respectively 16.5% and 56.0% higher. The two structures leak first at the side of the rotating shaft and the middle of the seal gap respectively when the seal fails. The opposite tooth structure has higher seal capacity and seal reliability.

Key words:  seal device; pole tooth position; pressure resistant performance; magnetic fluid;finite element simulation

LIU Yong, YANG Jian-wei, LI De-cai, et al. Influence of the pole teeth position of magnetic liquid seal device on pressure resistant performance［J］.Journal of Mechanical & Electrical Engineering, 2021,38(11):1424-1430.