Sealing Performance of Labyrinth Seals against Small Oil Particles in HDDs

Abstract

Small oil particles generated from lubricant for ball bearings in HDDs sometimes cause fatal problems such as head crashes. A labyrinth seal is often used to prevent oil particles from scattering onto the disk surfaces. In this paper, the sealing performance of labyrinth seals for small oil particles is investigated numerically and experimentally. Two types of labyrinth seal are considered, one a straight-type and the other a bent-type seal. It was found that the sealing capability of the labyrinth seal is generated by the centrifugal force exerted on oil particles due to disk rotation when they pass through the seal gap.