The bit performance evaluation of production wells in Western Raman field and optimization of the bit jet diameter selection

In this study, qualitative evaluation of bit performance and optimization of the bit jet’s diameter selection were conducted in terms of the drillings in the Western Raman region whichis Turkey’s biggest oil production field. Therefore, the parameters of drilling and bit parameters were analyzed. Rheological properties of the soil, flow, total in-series, annulus and total pressure losses on the drill bit, power spent from the surface (Hydraulic Horse Power-HHP) for pressure losses, Bottom Hole Assembly ( BHA), drilling meter cost, weight on the bit (WOB), Revolutions Per Minute (RPM), and jet speed were investigated. For this purpose, in the second stage of the drillings carried out in the Western Raman field, the data of fourteen wells including five wells drilled with PDC drill bit 8 ½’’ in diameter, five wells drilled with standard bit and four wells drilled with insert bit were utilized, and the performance of these bits were evaluated in terms of quality. Upon comparing and analyzing the graphs created based on these data, the PDC drill bit was found to be much more efficient than insert and standard drill bits in terms of time and correspondingly cost. In the second stage of the study, optimization of the bit jet’s diameter selection was performed with Bingham Plastic model for maximum hydraulic power of the bit. After the optimization, it was detected that the optimum jet diameters found for the data of fourteen wells can yield a better performance in the drillings in this site and the optimum drill bit is PDC bits including 6 jets with 6/32", 7/32" and 8/32" diameters according to the condition of the well.