Parameter Optimization and Selection of PDC Bits for Xujiahe Formation in Western Sichuan

Xujiahe formation(T3x5)in Western Sichuan,is a deep foramtion and rich in natural gas.Usual cone bits and PDC bits wear quickly,so they are unsuitable for this formation due to tight rock,high content of quartz and high abrasiveness.So it is difficult to select the suitable bits with high penetration rate.In order to increase ROP and shorten drilling cycle,the finite element model of cutter and rock were created by ABAQUS based on the rock properties and bit design theory.The key bit structure characteristics for Xujiahe formation such as crown profile,cutter structure,wing numbers,hydraulic structure and stability are determined in line with the bit design thoery.PDC bits with high aggressiveness as well as anti-abrasiveness and impact-resistance should be employed for formation T3x5-T3x3,hybrid cutter bits with high anti-abrasiveness used for formation T3x2.The application results indicate that selected bits increased footage by 27.57% and improve ROP by 40.19% on average.