Experimental and analytical study of the side cutting ability of drill bits

Drilling highly deviated wells such as extended reach and horizontal wells is frequently encountered in drilling operations.Drilling a highly deviated wellbore is more expensive compared to conventional vertical well and a substantial portion of drilling operation costs comes from the use of PDC drill bits.Therefore, improving the efficiency of the drill bits would result in a significant reduction of the costs and non-productive time (NPT) of drilling operation.This in turns requires a comprehensive knowledge of bit and rock interaction.Even though several studies have been conducted in this area, they were mainly focused on face-cutting efficiency without much emphasis on the side-cutting ability.The side-cutting ability is an important characteristic of drilling bits, particularly for PDC drill bits.Side-cutting ability directly impacts deviation control, wellbore stability and borehole quality, drilling performance parameters, tripping operations, cuttings transport performance, casing running assurance, real-time data acquisition, drag and torque, etc.Therefore, conducting research on side cutting ability of PDC bits would eliminate/reduce many problems originated by bit-formation interaction. OBJECTIVES AND APPROACH BHA ModelingIn the directional drilling process, the Bottom-hole Assembly (BHA) transfers load and torque to the bit which should have the ability to drill both axially and laterally.