Research And Development Of Monitoring And Forecasting System For Drilling Engineering Accidents

Drilling is an important link in petroleum and natural gas exploration and exploitation. The engineering accidents threaten drilling safety seriously during the whole drilling operation. The occurrence of accidents has serious impact on the drilling efficiency and quality. The drilling engineering accidents can be avoided by using some techniques. The development of monitoring and forecasting system for drilling engineering accidents is necessary in declining the incidence of accidents, and it also has great meaning to reduce drilling cost and optimize drilling.The analysis and judgment of drilling engineering accidents mainly depend on the wellsite data. The wellsite data is stored in different kinds of databases, and the formats of data are not unified. In order to get unified data, wellsite information transfer specification(WITS) is studied in detail and then a development plan of WITS data interface is proposed. By the interface, firstly, the logging data is converted to the format of WITS. Secondly, the WITS data is transmitted from comprehensive logging to client by using serial or network. Finally, the logging data is stored in private database. The data which is used to judge drilling accidents is got from the private database. The development of WITS data interface makes the data sharing come true.Recently, the analysis and judgment of drilling engineering accidents are mainly done by field engineer technicians. This judgment method is limited by person’s energy and skill levels, and the efficiency of the forecast is difficult to guarantee. Meanwhile, most smart systems for monitoring and forecasting have some defects. For example, some aren’t able to judge all kinds of drilling accidents and some use only one method of judgment. In order to improve the efficiency of the forecast, the change laws of the sign parameters of the drilling accidents are researched. At the same time, the pros and cons of the basic judgment methods are researched too. On the basis of these researches, a method which combined threshold with fuzzy logic is proposed to judge drilling engineering accidents. The threshold module gives an absolute judgment result by judging whether the sign of parameters exceeds the safety threshold or not. According to the fuzzy relationship matrix, the fuzzy logic module normalizes the characteristic parameters and gives a probability judgment result. Finally, according to experiences of field engineer technicians, two judgment methods are integrated to monitor and judge drilling engineer accidents.In order to develop a software system for drilling engineering accidents monitoring and forecasting, an object-oriented language C# and a software development platform VS2010 are selected. The system has two important parts, one is WITS data migration interface, and the other is drilling accidents judgment module. On the basis of the development programs, a complete set of software system for drilling engineering accidents monitoring and forecasting is developed.In order to verify the function of the WITS data interface, some tests are made in laboratory firstly and then some tests are made in a logging company. The test result shows that the drilling data can be transferred from the drilling instrument to the private database by the interface. Some simulation tests are made in laboratory in order to verify effective and feasible of the drilling accident judgment method. The method is combined threshold with fuzzy logic. The laboratory test result shows the drilling parameters can be monitored in real time, the mutation parameters can be discovered timely, the drilling accidents can be judged and a forecast can be given by the monitoring and forecasting system. The system meets all functional requirements steadily.