Load Spectrum Test And Application Research Of Key Rolling Functional Components Based On CNC Machine Tool KPI

The core performance indicators of the key functional components of CNC machine tools directly determine the pros and cons of CNC machine tools.This article takes the National Science and Technology Major Project as the research background,and focuses on the load spectrum test and application of key rolling functional components based on the CNC machine tool KPI system.The KPI system of CNC machine tools was established,and the importance of the first-level indicators of CNC machine tools was determined: accuracy,reliability and efficiency;The load spectrum of key rolling functional components(rolling linear guide pair and ball screw pair)that directly affect the key indicators of accuracy and reliability of CNC machine tools is selected as the main research content,and the load model and life prediction model of rolling functional components are established.The specific research content is as follows:(1)The KPI system for CNC machine tools for processing typical parts is established.Aiming at 14 machine tools for processing typical parts of a military research institute,taking the machining of rotary shaft parts as an example,accuracy,efficiency,and reliability are selected as the first-level key performance indicators.Based on this,14 secondary key performance indicators are further proposed and The method of determining the weight and quantification of each key performance index is established,and finally the KPI system of CNC machine tools is formed.(2)The load test is designed to obtain the cutting force signal and the signal preprocessing method is studied.For the milling process of the Institute's vertical machining center,9 typical test conditions are determined,and then a cutting test is performed and a cutting force signal is collected for the typical condition,then the collected cutting force signal is preprocessed.(3)The load spectrum design method of key functional components is studied.Rainflow counting method is used to count the collected cutting force signal,and the joint probability distribution function of cutting loads mean amplitude is determined.Then,the fitted distribution model is used to extrapolate the load cycle frequency to establish a two-dimensional spectrum of the load mean amplitude.The load model of the key rolling functional components of the machine tool is analyzed,and the load distribution model is established to lay the foundation for life prediction.(4)The established KPI and load spectrum of key functional components of CNC machine tools are applied.Based on the established CNC machine tool KPI system,the comprehensive performance evaluation of the machine tools before and after remanufacturing is carried out.The life spectrum of the machine tools is checked by using the compiled load spectrum and the established load model of key rolling functional components,and its life prediction model is established.