A novel straightness error prediction method incorporating machining errors of linear guideways

Abstract

In the assembly process of a linear guideway, straightness error is primarily influenced by machining errors and the sequence of bolt residual preload. Accurate prediction of straightness error is a necessary prerequisite for improving linear accuracy. The primary objective of this research is to propose a novel method for the accurate prediction of straightness errors in linear guideways under different bolt tightening sequences. First, based on the analysis of the linear guideway load state, a prediction method for straightness error incorporating the machining errors of the guideway and the bed mounting surface is proposed. Secondly, by comparing the experimental results of the guideways assembled under three different initial tightening sequences, the prediction accuracy of straightness errors reaches over 88 %, validating the accuracy and repeatability of the prediction method. Meanwhile, the impact of the tightening sequence on the straightness error is discussed. Finally, based on the straightness error prediction, the tightening strategy is optimized to improve the accuracy and assembly efficiency of the guideway, demonstrating the practicality of this prediction method. The findings of this research enable accurate prediction of straightness errors in linear guideways under different tightening strategies, providing manufacturers with references and guidance during the assembly process.