Post-op bore profile estimation of workpiece clamped using three-jaw chuck

Abstract

Estimating bore profile is important to select an appropriate tool for precision manufacturingin the process planning stage. Also, it helps in reducing the rejection rate of the process. Amanufacturer might not be well-equipped and want to make their best with the resource onhand. Three-jaw chuck allows machining a wide range of workpiece, mostly circular parts ina lathe. However, clamping via a three-jaw chuck distorts the workpiece. In this study, thedeformation of the bore profile was investigated numerically for circular parts. Finite elementanalyses were performed to examine dimensional variation for various materials and differentwall thicknesses under fully elastic plane stress conditions. The stressed workpiece had atriangular form. Results showed that wall thickness and materials are important parameters onthe triangulation of bore diameter. A simple calculation method based on thick-walled vesseltheory was proposed to estimate the tolerance grade of the workpiece. This simple methodprovides the opportunity to reduce the rejection rate in the mass production of circular parts.