| With the development of the materials industry and the PDC bit design,PDC bit technology for hard formation is also improving. As the rapid development of the oil industry in recent years, the number of deep exploratory wells increased year by year,and the drilling difficulty are increasing. Various problems,such as the poor drillability in deep stratum, long drilling cycle and the high drilling costs has become ever more.Based on requirements improve the penetration rate, reduce drilling costs and reduce the number of bits used in construction site,this paper simulated the drilling process of PDC bits by the use of LS-DYNA,and work out the performance testing program for impact resistance, abrasive resistance and thermal stability,and simulated the residule stress of PDC by the use of ANSYS.With respect to the effect of the cutting angles,cutting speed and drilling speed on the drilling process,this paper simulated the drilling process of PDC bits by the use of a well-known finite element package,LS-DYNA. Based on the results of analysis, the relationship curve between the change of cutting angle and the drilling efficiency has been established,and the author also analyzed the influence of the drilling process,which responde to the change of cutting angles and cutting speed respectively. And this paper not only analysied the residual thermal stress of PDC by the use of ANSYS but also worked out the performance testing program for impact resistance, abrasive resistance and thermal stability, and simulate the impact process of PDC by the use of LS-DYNA 3D. The impact speed should be reduced appropriately during the great impact working conditions. With the increase of the thickness of carbide layers, the stress of the gleba will be more dispersed, and the stress distribution between diamond layer and carbide layer become more uniform. With the decrease of the thickness of carbide layers, stress concentration is more vulnerable underside the gleba thereby affect the life of PDC bit.
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