Research On Availability Security Technology Of Processing Center Based On QFD

The CNC machine tool is an important component used in modern technology andmanufacturing equipment. The quality of CNC machine tools typically symbolizes the level ofindustrial modernization and comprehensive strength of a nation. Given that China has shiftedfrom being a mere manufacturing country to a major manufacturing powerhouse, the CNCmachine tool enterprises of the world have considered China as their main market. China hasbecome an important platform of competition among the world’s top enterprises. However, theresearch and development in our country lags behind compared with other countries engaging inthe production of CNC machine tools. Moreover, the availability is poor and the market share ofdomestic products is low. Thus, domestic companies have strived to occupy the local market anddevelop key technologies to solve the urgent demands to improve the level of independentinnovation of China’s machine tool industry, gain a wider market share, as well as enhance thelevels of China’s equipment manufacturing industry and comprehensive national strength.The study, combined with the National Project, introduces the ideas and methods of knownapplications in the market to ensure quality in the practice of CNC machine tool availability. Thestudy proposes new ideas on the functions of CNC machine tool availability and housingconstruction availability. Starting from the demand for availability in the machine tool market,the study transforms the tool user demand for usability into all aspects of the design,manufacturing, and repair of the product chain of CNC machine tools, using the analytic networkprocess method (ANP), structural equation modeling (SEM), and the failure risk assessmenttechniques based on Grey theory. The study then builds CNC machine availability mechanismtheory and practical foundation by taking the representative CNC machine tool product—themachining center—as the research object. Combined with the function of CNC machine tools,fault features, user demand information and machine fault information uncertainty, we study theavailability of the technology of machining center based on QFD.The main contents of this paper are explained below.First, the structure of the index system of machining center availability requirements is built.This paper introduces the idea of starting from the product usability requirements of users inQFD. On the basis of previous studies, it then establishes the initial index system of the usabilityrequirement of the machining center by reviewing the relevant literature and conducting in-depthinterviews. Next, the initial index system of the usability requirements of the machining center isscreened by two rounds of expert consultation method. Afterwards, the index system is designedusing the pre-survey questionnaire validation, thus improving the index by factor analysis andreliability analysis. The index system lays the foundation for the housing constructionavailability. Second, we analyze the combined machining center usability requirements. Determining theimportance of customer requirements is a key step in QFD construction. One importance ofcustomer requirements is that they reflect the product attributes and the degree of importanceattached by the customers to such attributes. This is an important basis for the effectiveallocation of resources and scientific decision-making in the QFD planning process. This studyuses the ANP-SEM method to analyze the basic importance of usability requirements. Itmodifies the importance of usability through an analysis of the Entropy weight method，with thehelp of the market competition evaluation matrix. The study also establishes the combinationweight vector by coefficient of variation, and determines the importance of the combination ofuser availability requirements, thus providing the basis for the analysis of technical requirementsof the machining center and the formulation of availability security technology.Third, we analyze the technical requirements of machining center availability based onQFD. The housing availability of the machining center is built based on the principle of QFD.The study translates the customer requirements on product availability into each link of themachining center production chain. By analyzing the various factors of mining fault, the studydetermines the improvement target by mining fault factors and then providing technical supportfor the establishment of the available security mechanism. To achieve this, the calculationmethod of quantitative and qualitative indexes in the matrix is explored. This study then buildsthe reliability model and maintenance model of the machining center subsystem and fault modeby small sample modeling method; it also obtains the quantitative index via shuffled frog leapingalgorithm. Considering the fuzziness of index, the study is able to determine the quantitativechanges in the qualitative indexes. Then, the technical requirements of the risk of machiningcenter based on QFD-Grey risk assessment model are analyzed. Finally, by means of thetransferring matrix, the study translates the usability requirements into the actual technicalrequirements of the machining center. The key technical requirements are outsourcing as well asthe manufacturing and assembly components.Finally, we determine the availability security technology of the machining center. Thestudy proposes the analysis of the availability technology of the machining center by startingwith the requirements of MTBF and fault diagnosis, which are the two most important usabilityrequirements mentioned earlier. In the aspect of MTBF, this study proposed the outsourcing ofmanufacturing assembly process reliability guarantee technology from two aspects. For thereliability of purchased parts, the study uses the F-EAHP method（Fuzzy-Extension analytichierarchy process，F-EAHP）to evaluate the reliability of the supplier and to formulate theapproval process and checklist for the purchased parts. For the reliability of the manufacturingand assembly process, some concrete methods are proposed to be used during the assemblyprocess. In the aspect of fault diagnosis, the fault diagnosis technology of the machining centerbased on DEMATEL-ISM is also proposed.