Total Specific Energy (TSE) as a new indicator of drilling efficiency

Knowing the data from drilling works which had been carried out in a given area gives the opportunity to develop the next borehole with great precision. An important element of the design is to analyze and interpret data in detail, which can be used during the following drilling process. Based on a literature analysis, certain methods of the selection of drill bits have been indicated. Mechanic specific energy curves of drill bits applied in drilling works in northern Poland have been compared. The drilling works took place in the Precambrian platform. The compared mechanic specific energy curves were calculated with the use of R. Teale and H. Rabia equations. A relation between mechanical specific energy and pressure loss in polycrystalline diamond compact drill bits was determined. New drilling ratio TSE - Total Specific Energy which considers hydraulic power energy in the nozzles of the drill bit was calculated.