Simulation Research On Rock Breaking Of PDC Bit With Directional Reaming While Drilling

Directional reaming while drilling technology is mainly used to optimize the well structure,improve the cementing quality and prevent the neck sticking of complex formation in the oil and gas well.Drill bit for reaming while drilling is the main product about the technology.The design technology,simulated analysis technology and field application technology about the product still refer to foreign products and experience,which would restrict the development capability of new type products.Based on the disadvantage of the above phonomenon,the basic thetory of drill bit for reaming while drilling is analyzed,and the rock-breakage mechanism simulation technology are researched.It will provide an important designing and analysis method.The research content and findings include:1.The digital modeling theory and method are researched and developed.which extend the tooth model library.2.The geometric model of gage pad and computation force model are researched,which make the PDC digital simulated analysis technology be much better.3.The sphrical coordinate system is researched,the computation accurace between the cutting structure and bottom and wall is improved compared to the digital simulation system with cylindrical coordinate system.4.The modeling method of several typical kinematics mode are researched.5.Performance analysis and evaluation theory of PDC drill bit are researched.6.Based on the above researchresults,develop the PDC drill bit for reaming while drilling simulation system,which can compute contact components?cutting components?cutter load?bit load and performance evaluation components under ideal drilling condition and steering drilling condition.7.The reamer gradient has effect on the working performance for specific drill bits under different working conditions.