Reliability Analysis And Optimization Of The Fast De-ballast System In Semi-submersible Platform

The offshore operation capacity of a semi-submersible lifting and dismantling platform depends not only on the performance of the crane,but also on the fast deballast capacity of the platform.The semi-submersible lifting and dismantling platform realizes the attitude adjustment through fast de-ballast system,which directly affects its floating state,and provides support for the salvage,mining and cargo lifting operation of the dismantling platform.Reliability is one of the most important quality attributes of components,products,and complex systems.Therefore,it is great significance to analyze the reliability of the fast de-ballast system,identify hazards,evaluate the severity,evaluate the reliability of the fast de-ballast system in the design stage,and optimize the reliability of the system structure.The specific research content of this paper is as follows:1)Based on the function and working principle of the fast de-ballast system,the subsystems and important components of the system are divided.Then,the failure mode and effect analysis of the system is carried out on the basis of considering the system itself,design defects,quality defects,mis-operation and other factors;2)Based on the qualitative analysis of failure modes and effect analysis(FMEA),this paper improves the risk factors in the traditional model and introduces new risk factors under the influence of factors such as component replacement difficulty,cost and component maintenance difficulty.On the basis of the enhanced FMEA model,it is combined with the fuzzy analytic hierarchy process(Fuzzy-AHP)and fuzzy comprehensive evaluation to establish a system reliability analysis model,and then obtain the reliability of related subsystems and components in the system,and complete the identification of potential risks and the determination of weak links in the system;3)Based on a K-mixed redundancy strategy RRAP,different redundancy strategies are given to the corresponding subsystems or key components by combining with the common system structure in the fast de-ballast system,so as to establish the reliability multi-objective optimization model of the system,and solve it in combination with the powerful NSGA-II algorithm to obtain the optimal redundancy configuration of the systemIn this paper,the fast de-ballast system is taken as the research object,and the failure modes and effect analysis of the system is carried out.On this basis,the system reliability analysis model is established to determine the weak links of the system,and the advantageous redundancy strategy is used to build the reliability optimization model of the fast de-ballast system in a more complex RRAP.At the same time,the efficiency and advantages of the proposed model are verified based on the analysis of the calculation results of the model,which provides a certain theoretical basis for the reliability analysis and optimization of the rapid ballast system.