Force characteristics and two-dimensional pressure fields of air flotation units with different numbers and distribution radii of orifices

Abstract

Air flotation rails are widely used in semiconductor production lines for handling components such as liquid crystal glass substrates and wafers. In this study, the effects of the number and distribution radius of the orifices of the basic component (hereinafter referred to as air flotation unit) of the utilized air-suspension orbit were theoretically and experimentally investigated. The pressure distribution of the air flotation unit was first calculated using the Reynolds equation. The flotation forces and two-dimensional pressure fields of six different air flotation units with different numbers and distribution radii of the orifices were then experimentally measured. Based on the experimental data, we analyzed the effect of the inertia item of the flow, the impact of the no-flow region within the distribution circle, and the changes brought about by the number and distribution radius of orifice, etc. The findings of this study afford important theoretical and experimental references for the design of air flotation rails.

Keywords

Air flotation two-dimensional pressure field number of orifices distribution radii of orifices

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