基于灵敏度的换刀时间和工艺动态可靠性研究  

Research on Tool Change Time and Dynamic Reliability of Machining Process Based on Sensitivity Analysis

作　　者：王新刚[1] 陈晓明[2] 闫明明[1] 

机构地区：[1]东北大学机械可靠性与动力学研究中心,河北秦皇岛066004 [2]哈尔滨工业大学机械工程学院,哈尔滨150001

出　　处：《兵器装备工程学报》2017年第1期1-6,共6页Journal of Ordnance Equipment Engineering

基　　金：国家自然科学基金资助项目(51475086);辽宁省自然科学基金资助项目(2014020026);河北省自然科学基金资助项目(E2015501073);教育部高等学校博士学科点专项科研基金资助项目(N152304004)

摘　　要：将刀具的切削参数作为随机变量,结合矩估计、最大似然估计和动态可靠性分析技术,建立了机加工艺系统的动态可靠性数学模型,推导了各工序刀具的失效率计算公式;以刀具失效率为判据,建立了确定临界刀具及换刀时间的方法;在此基础之上,以最大限度利用刀具为研究目标,在确定被更换刀具的同时应用可靠性灵敏度分析方法确定刀具最敏感切削参数,通过改变最敏感的切削量参数提升刀具及整体工艺系统的可靠度,使刀具能够继续工作,延迟换刀时间;研究结果表明:当整体工艺流程系统可靠度低于某一阚值时,应用该模型能够迅速准确找出失效率最大的工序所使用的刀具并对其敏感参数进行控制,从而确保刀具还能满足工艺可靠性要求,最大限度的利用刀具,减少换刀次数,降低成本,保障整体工艺系统的高可靠性。Combining the moment estimation, the maximum likelihood estimation with the dynamic reliability analysis method together,the study built a mathematical model of the dynamic reliability for machining process under the premise of seeing cutting parameters as random variables,and the failure rate formula of each tool involved in each operation was deduced as well. Based on failure rate,a algorithm for defining the critical tool and its corresponding tool change time was proposed. Beyond that,for making the most use of every tool,the given model can pick up the cutting parameter which has the largest sensitive degree to the reliability via sensitivity analysis method. Then the selection of relevant stock removal should be changed so as to improve the reliability of cutting tool and the whole process system,as well as enabling the cutter continue to work and delaying tool change time finally. The results show that when the reliability of overall machining process is lower than a given target,and the proposed model can identify the tool which has the biggest failure rate quickly and accurately and then control its sensitive parameter so that canmeet the requirements of whole process reliability before it loses efficacy. Ultimately,the manufacturing process can maximize the cutters＇ potential and thus reduce the number of tool changes,as well as the production costs while ensuring high reliability of the overall process simultaneously.

关 键 词：工艺 刀具 可靠性 灵敏度 换刀时间 

分 类 号：TH122[机械工程—机械设计及理论]