Analysis of Puncture and Prediction of Crack Fatigue in Drilling Tools

In recent years, the drilling technology of directional wells and large displacement wells has been widely used, which has greatly improved the reservoir development efficiency. However, the “stabbing” accidents in the drilling of the inclined section drilled frequently occur frequently. In view of the above problems, this paper uses the finite element method to take the well “003-H1”, which is more serious in the drilling tool, as the research object, and deeply analyzes the cause of the “stabbing” of the drilling tool and the prediction of the crack extension period. The results show that the “piercing” of the drill pipe is mainly caused by the fatigue failure of the drill pipe. The crack on the surface of the drill pipe increases with the slope of the construction. The crack changes rapidly from elastic expansion to plastic expansion, and the fatigue life is “breaking” down, move down to create a slanting point position, which can reduce the occurrence of drill pipe “stabbing” accident.