Reliability Analysis Of Cnc Machine Tool Main Drive System Based On Functional Hazard Analysis

Computer Numerical Control machine tools are the important equipment to the development of national economy and national defense construction. The accuracy, processing quality and productivity of machined components and tool's life are directly influenced by the reliability of CNC machine tools'main transmission system. As an important technology, 3F—the Fault Mode and Effect Analysis (FMEA), Fault Tree Analysis (FTA) and Fault Reporting Analysis and Corrective Analysis (FRACAS)—has great significance to ensure the reliability of the machine system's normal work. But in practice, 3F technology is lack of strong theoretical basis and technical support for the choice of top event in FTA often by experience. And the fact that Functional Hazard Analysis (FHA) can be only taken as supplement for FMEA is required by the technology itself, limiting the use of FHA result and also making FHA can't play its own important role in using FRACAS, finally the comprehensiveness of reliability analysis is affected.In this situation, FHA to CNC machine tools'main transmission system is done firstly in this paper, and its output is taken as the input of the Fault Tree Analysis. Then the FMEA is finished by combining that with the result of FHA to Main Drive System. Meanwhile, in this paper, the output of FHA, FMEA and FTA to the system is applied and the closed-loop control system at outfield of main transmission system is established when the FRACAS technology is implemented to Main transmission system of CAN machine tools. As the result, system reliability analysis can be effectively controlled from potential fault mode to "reality fault ".