Characteristics of rock mechanics and PDC bit optimization of glutenite formation in the Pearl River Mouth Basin oil fields


1 State Key Laboratory of Petroleum Resource and Prospecting (China University of Petroleum, Beijing), China

2 Zhanjiang Branch Company of China National Offshore Oil Co., Ltd., Zhanjiang, Guangdong, China

3 Northwest Gas Station, PetroChina Southwest Oil & Gas Filed Company, Jiangyou, Sichuan 621709, China

4 Chengdu Best Diamond Bit Co.,Ltd., Chengdu, Sichuan, China


In order to increase the Rate Of Penetration (ROP) in the glutenite formation of the Pearl River Mouth Basin (PRMB) oil eld, the mineral components of drilling detritus were tested, and laboratory tests of Uniaxial Compressive Strength (UCS), drillability and abrasivity were undertaken. Prediction models of the rock mechanical properties of the glutenite formation with logging data were established. An abrasivity test was done using a modi ed rock drillability tester with micro Polycrystal Diamond Compact (PDC) bits. The bits used in the glutenite formation were discussed to nd out the reason for the low ROP.
According to the properties of the rock mechanics and the bit applications of adjacent wells, structures, such as tooth type, crown pro le, tooth assembly parameters and the hydraulic structure of selected bits, were optimized. A new tiger tooth and an anticollision tooth for the optimized PDC bit were developed to increase shock and wear resistance in glutenite formation. Compared with conventional bits used in glutenite formation, the optimized bit raised footage and ROP by 131% and 48%, respectively. The new method, combined with the properties of rock mechanics, bit application and bit structure, is simple and e ffective to guide the bit design for glutenite formation.