Abstract: In hard disk drive manufacturing, the tolerance ring is commonly used for coupling a bearing cartridge to an arm actuator. Further, the tolerance ring can prevent slippage between the arm actuator and bearing assembly during operation of disk drive or during shock events. The metal scratch occurred in the tolerance ring installation process cause a number of particles. The main purpose of this analysis is to improve and to investigate behaviors of the tolerance ring using finite element 3D model for reducing the particles. The result shows that the developed vulnerable point effect less movement of the tolerance ring, the particles were decreased because the metal scratch was eliminated.