Research On Degree Of Inherent Safety Of Machanery & Electrical Products

With the rapid development of global economy and technology, machinery & electrical products become larger and more complex, and used widely. The traditional type of product safety design on the basis of experience and lessons learned can no longer meet the increasing demands on product safety, but also can not afford huge loss. Therefore, in the design stage through the scientific hazard analysis and risk assessment to make the safety risks of the various stages through the life cycle to an acceptable level has become one of the topics that the product quality as well as system safety researchers focus on.In order to improve the product’s safety, there has been the discussions on inherent safety. Based on the original studies on the quantification of products’safety, this thesis researches inherent safety of machinery & electrical products because of the past quantitative methods and assessment considering but not adequately products’degree of inherent safety.Firstly, the concept of the degree of inherent safety has been proposed, based on the researches of the inherent safety, and its contents were analyzed. And the qualitative assessment model of degree of inherent safety was put forward by the hazard of substance, the complexity of structure and reliability of critical components. Secondly, focus on the products with safety device, the fault state that most likely occur in safety device failure mode was defined by fuzzy theory, and the effect of the residual safety function to the occurrence of accident was analyzed, and the quantitative model of degree of inherent safety was set up by applying the fault tree analysis at the same time. Moreover, the influence of the safety device on the degree of inherent safety was analyzed and its calculation process was provided. The research provides the theoretical basis and method for the selection of design to the product safety, but also lays the theoretical foundation for the establishment of a comprehensive and scientific assessment system for product safety. Finally, taking the elevator for example, its applicability was verified.