Branch Of The Well Trajectory Design And Software Development

Multilateral well technology originated from 1950s, but it develop quickly till 1995 year. Compare this technology with drilling cluster wells and a single horizontal well, in some distance, multilateral technology can save costs and working hours, so it become the one of the most topical technology and cause international attention. Based on the research result of the predecessor, this paper detailed analysis the multilateral trajectory design and factors must to be concerned, and developed a trajectory design software, at the same time, studied the multi-junction mechanics status and the correlative rules.According to multilateral have been drilled up to now, the paper batted around the multilateral trajectory type and its adaptability respectively combining the oil reservoir geology, and the factors must to be concerned and the affect each other, then summarized the multilateral trajectory design principle, methods and steps.On the trajectory design and calculation method, the paper studied the 3D trajectory design and calculation, presented a rule of the turn azimuth diagnoses and gave the perfect Dog-Leg checking model, meanwhile, deduced a new simple method of two target directional trajectory design and the space circular arc method, which can be used to design the 3D trajectory widely, at the same time, presented the method of the subsection trajectory design and calculation that is the basis of the computerizing the program, then set up a new model to optimize the multilateral trajectory and solved the model by the RPH method at the first time.Based on the mechanics characteristic of the multi-junction in multilateral well, the paper studied the rule of stress speared at the multi-junction at the first time, which used the finite element method (ANSYS Software), and analyzed the influence of deflection radium & the direction on it, and the destroy rules of the multi-junction, summarized a very important rule that the optimum direction of the drilling a lateral is the direction of the maximum formation horizontal stress.And at the same time, the paper presented the software of multilateral trajectory design and 3D visual using VB combined with OpenGL based on the theory mentioned before. The software can show the relationship between space spread of trajectory and trajectory in the virtual reservoir for visualization in scientific computing is used. So the software can supply the designer with much intuitionistic design and control.The achievement of this paper can be widely used to the practice design of multilateral well, directional well and horizontal well.