Research On Drilling Complex Incidents And Accident Diagnosis Based On Expert System

Drilling is one of the most important means in petroleum and natural gas exploration and exploitation. During the drilling operation, drilling complex incidents and accidents are the threat to the entire process of drilling, which have a serious impact on the drilling speed, quality and economic benefits. It can be summarized from the lessons of drilling accidents many years that the main reasons are the no timely find of the precursor of drilling complex incidents, the inaccurate judgment and process of the drilling accident type. For the current situation of oilfield development and problems in drilling operation, the inaccurate reasoning model based on the certainty factor is used to establish the drilling complex incidents and accident diagnosis based on expert system.Firstly, the knowledge base of drilling complex incidents and accidents is established, through which a large number of empirical knowledge of the domain experts and field technicians are stored in the computer completely and rationally. Not only the changing conditions of drilling complex incidents are required to adapt, including the prevention and treatment programs to the drilling complex incidents, but also the well drilling services are needed for the diagnosis of drilling complex incidents.Secondly, the drilling complex incidents and accident diagnosis based on expert system is proposed in the paper. In the design process of expert system, the program implement module of knowledge is taken as the reasoning machine to establish the inaccurate reasoning model based on the certainty factor. Comprehensively considering the uncertainty value of evidence and the uncertainty factor of rules, the uncertainty value of final conclusions can be calculated and therefore the judgment and decision can be made accordingly.It can be found from the analysis of case study of drilling accidents that the system can reflect the real drilling complex incidents and accidents, make the accurate diagnosis and treatment to the accidents, play an important role in the reduction of accident handling time and the accelerate of the drilling process speed. The system is the combination of artificial intelligence and computer technology. It is the free employed drilling accident experts for the on-site drilling crew, which can provide a strong support to the drilling technical personnel.