Reliability Analysis Of The Main Transmission System Of The Heavy CNC Machine Based On Critically Analysis

Reliability analysis is one of the critical projects in the reliability engineering of heavy CNC machine.It serves as the key technology in the reliability engineering, which will contribute to indentifying the weakness and key items of a system, and evaluating and improving system design reliability for the machine tool. In the process of combined machining,its own heat source, processing conditions, operational technical personnel as well as other effectswill cause low processing reliability of heavy CNC machine. Therefore, it has become one of the difficult yet imperative works for the reliability analysis of heavy CNC machine.To build the use stage reliability analysis for the heavy CNC machine, we combined the thesis dissertation with the development of the "High grade CNC machine tools and basic manufacturing equipment" major technology project, where a certain type of domestic heavy CNC machine is researched. It can help us to carry out reliability work of the heavy CNC machine and provide us theory reference for the design improvement. Specific researches are focused on the following several aspects.(1) A suggestion framework is put forward on how to start the reliability work of the main transmission system of heavy CNC machine,and to coordinate the development of reliability work between different product manufacturers’ departments as well as using manufacturers, to let them know their responsibilities and tasks.(2) The FMECA of the main transmission system is carried out following the rules of GJB1391-2006( "Guide to failure mode, effects and criticality analysis"). An FMECA report is formed,which can be used as a basis for following reliability work.(3) On the basis of FMECA, the PC-FMECA based on fuzzy hierarchy analysis with consideration of cost of failures is studied.Then a mathematical model is presented to provide the company a theoretical support of whether carrying out maintenance activities of failures or design improvement.(4) In order to improve study FMEA on heavy CNC machine, MFMEA is put forward based on 5M1 E from the perspective of quality management.It can help the product manufacture and using manufacture to distinguish their liability. By using SOP method, using manufactures can improve the efficiency of production management and guarantee a high using reliability of machine tool.Through the work above, the standard procedure of reliability analysis work has been built, and the responsibilities of all manufactures are cleared, which improved the efficiency the reliability work. It significantly enhances the reliability of the heavy CNC machine, and gives some useful references to the design of follow-up heavy CNC machines.