Since the element action (e-action) is the smallest motion unit in realizing systems function, its reliability plays an important role in system operating ability. In this paper, a new method of CNC machines reliability analysis based on e-action is proposed. Firstly, the definition of e-action reliability is studied and the mathematical model is built. Then the methodology of FMECA based on e-action is introduced. Finally the grinding carriage feed movement is taken as an example to illustrate the methodology.

Machining center is a complex mechatronical product. Because of numerous influencing factors on its reliability, parts of their inaccurate description and the uncertainty of its failure behaviors, it is very difficult to analyze its reliability by traditional reliability model which is based on probability theory. To solve this problem, grey system theory combined with GO method reliability analysis was presented, and sequentially a practical reliability analysis model considering various operating conditions of the components of machining center was established. The method was used in reliability analysis of hydraulic system of Tray Automatic Exchange Device (TAED) of machining center. Firstly, through a systematical analysis of hydraulic system of tray automatic exchange device of machining center, its basic structure model was summarized, and the model of GO chart for the hydraulic system was established. Then, the gray dynamic analysis for the hydraulic system was derived, and a feasible method of dynamic analysis for the performance reliability of hydraulic system was provided. Finally, the availability and correctness of this method in the analysis and reliability evaluation of machining center was verified by comparing the calculated result of this method with that of the traditional static GO methodology and the FTA. This approach provided a theoretical basis for the prevention of failures of the hydraulic system of tray automatic exchange device, the improvement of the system reliability and security, and the development of security controls.

In the early design phase of direct-drive hobbing machine, to allocate the reliability index scientifically and reasonably without the related reliability data, fuzzy analytic hierarchy process (fuzzy AHP) is used to allocate the reliability index of the main system units of direct-drive hobbing machine. This method is an effect way for multi-factor decision, which can consider the influence of the factors of every hierarchy on the machine maximatily and calculate the influence weights of the factors of every hierarchy quantitatively. Research on reliability allocation of direct-drive hobbing machine illustrate that this method is suitable for reliability allocation during innovative design phase.

To eliminate the early failures and improve the reliability of numerical control (NC) machine tools, the comprehensive technology for these works is proposed in this paper. Firstly, model is established to describe the early failures of NC machine tools, then the formation of early failures and mechanism of early failures elimination are studied. Secondly, a comprehensive technical framework for eliminating early failures is introduced, with some detailed process and implementation. Finally, example of NC rotary table is shown to illustrate the applicability and validity of the technology for eliminating early failures of NC machine tools.

To study the accurate calculation and failure mode diagnosis of supply chain, the idea that GO methodology is introduced into the reliability analysis of supply chain system is brought forward. Through analyzing detailedly every important factor leading to success of supply chain system and taking three-tier supply chain as the object, The GO model of reliability analysis of supply chain is found, which is universal. It can not only calculate reliability of supply chain system in detail, but also diagnose its failure mode and calculate its importance, which provides a way for improving and optimizing supply chain system. The example is presented to prove the method’s feasibility and validity.