Parametric analysis of mixed lubrication characteristics in work zone of strip rolling

Abstract

A theoretical model for mixed lubrication with more accurate contact length has been developed based on the average volume flow model and asperity flattening model, and the lubricant volume flow rate and outlet speed ratio are determined by integrating differential equations based on rolling parameters. The lubrication characteristics at the roll−strip interface with different surface roughness, rolling speed, reduction and lubricant viscosity are analyzed respectively. Additionally, the average volume flow rates of lubricant under different rolling conditions are calculated and used to explain the change rule of lubrication characteristics. The developed scheme is able to determine the total pressure, lubricant pressure, film thickness and real contact area at any point within the work zone. The prediction and analysis of mixed lubrication characteristics at the interface is meaningful to better control the surface quality and optimize the rolling process.

Keywords

mixed lubrication / rolling / film thickness / real contact area

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