Research On The Importance Of Mud Pump Equipment And Fault Risk Assessment Methods

Mud pump is one of the three major parts of the drilling rig.as well as the key equipment of drilling fluid circulation system,with many easily damaged parts and complex operating mode.In the process of drilling,the failure of important components will have a huge impact on the working performance of mud pump,and the reliability of mud pumps is directly related to the safety and cost-effective of the whole drilling process.So,it is necessary to study risk assessment of its important components and failure modes to assure normal operation of mud pump.Against F1600 gem mud pump,based on the theory of reliability centered maintenance,using improved fuzzy analytic hierarchy process(AHP),Monte Carlo method,failure modes and effects analysis(FMEA),risk matrix analysis and Borda method study the problems that importance degree evaluation of mud pump components and risk assessment of their failure modes,present an improved importance degree evaluation method and a new risk assessment method.The instance shows that these presented methods are accurate and feasible;these methods can provide a reference of method for related study and application involving the system reliability.In this paper,the main work and research results are as follows:1.Based on the study of principle and method of important degree evaluation and risk assessment,established the importance degree evaluation index hierarchy of mud pump system components,and laying a foundation for its importance degree evaluation.2.Presented a new method of important degree evaluation method based on improved fuzzy AHP and Monte Carlo method,and it can get 8 important from 20 major components of F1600 gems mud pump by this evaluate method.It not only reduces the subjectivity,but also avoids the tedious calculated process and the complex adjustment of the judgment matrix consistency,and the inadvisable of consistency criterion.3.The bi-level risk structure tree and FMEA analysis table that containing 18 kinds of failure modes and 47 kinds of failure causes with the influence degree and frequency degree is obtained by FMEA analysis for the 8 important components,sequentially,laying the foundation for risk assessment of 18 failure modes.4.Based on the bi-level risk system from the FMEA analysis table a new bi-level Borda method is proposed.By this new method,the Borda value of the risk events in the lower layer are obtained by traditional Borda method at first,then the bi-level risk analysis system is transformed into a single-level system by the technology of permutation and combination,thus the risk events in the upper layer finally can be sequenced by traditional Borda method.5.With F1600 gem mud pump as an example,applying bi-level Borda method,first of all,on the first floor get 9 sorting results for the 47 failure causes;on the basis,14 sorting results of the 18 failure modes are obtained.The results of the instance shows that the evaluation result of the bi-level Borda method and important degree evaluation proposed coincides with the actual situations,and can make quantitative analysis,simple and feasible.