Theoretical Research on the Novel Magnetic Fluid Seal Structure and Its Pressure Resistance

doi:10.3901/JME.2022.03.213

Abstract

Abstract: For a certain large-size main shaft and heavy equipment, the spindle will have a certain radial swing during high linear speed operation, which will cause seal leakage. The traditional single axial magnetic liquid sealing structure fails to meet the pressure requirements of the equipment when radial swing occurs. In order to solve this problem, and considering that the axial space of the main shaft sealing structure of the mechanical equipment is limited, a novel shaft-diameter-bidirectional magnetic fluid seal structure is proposed. The pressure resistance of the axial and radial magnetic liquid series seal structure in the single magnetic source magnetic circuit is theoretically studied, and the finite element simulation is used to numerically simulate the magnetic field strength in the seal gap of the seal structure. According to the pressure resistance theory of the magnetic fluid seal, the theoretical pressure resistance value in the sealing gap is calculated, and the influence of spindle radial runout displacement on the axial, radial and overall sealing performance of the system is analyzed. The research results show that for the sealing structure set in the article, as the radial swing displacement increases, the parallel magnetic resistance at the axial seal increases, and its theoretical pressure resistance value of the axial seal decreases. The parallel magnetic resistance at the radial seal decreases, and its theoretical pressure resistance value of the radial seal increases. Under the series action of both axial and radial seals, the overall pressure capability of the system remains within a certain range, which can effectively improve the pressure stability of the high-speed rotating shaft dynamic seal.

Key words: magnetic fluid, sealing, radial swing, magnetic field strength

CLC Number:

TB42

YUAN Fang, WANG Siqi, LI Decai, CHEN Duo, DI Nannan, LI Wenyi. Theoretical Research on the Novel Magnetic Fluid Seal Structure and Its Pressure Resistance[J]. Journal of Mechanical Engineering, 2022, 58(3): 213-220.

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