Paper: THE AFFECT OF DIFFERENTIAL PRESSURE ON MECHNICAL SPECIFIC ENERGY DURING DRILLING WITH PDC BITS

In the search for an improvement in rate of penetration in deep wells, the mechanics of rock failure during drilling has been reevaluated in order to understand functional relationships between the cutting process and the drilling parameters. Also, the relationship between wellbore pressure conditions and calculated mechanical specific energy is presented based on the laboratory results of rock cutting with polycrystalline compact diamond cutter under both the atmospheric and different magnitudes of differential pressure conditions. The analyses of experimental data, as well as the data presented in the literature lead to the development of an improved PDC model that accounts for the cutting removal process during PDC bit drilling. This process is highly related to both rock properties and downhole pressure conditions.