A Novel Diamond Hybrid Bit Improved Performance in Hard and Abrasive Formations

When drilling in extreme hard and abrasive formations, such as granite formation, the conventional polycrystalline diamond compact (PDC) will be seriously damaged and rate of penetration (ROP) will decrease significantly. To solve this problem, the integration of advanced material and optimized design of cutter structures is very important. Based on this idea, a novel diamond hybrid bit is designed in this paper by combing the PDC and impregnated diamond cutter. The impregnated diamond cutter was optimized from nine kinds of formula. The final novel hybrid bit has six blades with 28 PDC cutters, 25 natural diamond impregnated cutters, 6 flumes, and 8 nozzles. In each blade, the PDC cutters are placed in one row while impregnated cutters in another row. This special design provides the bit a double rock-breaking effect of both shearing and grinding, which maximizes drilling efficiency by improving ROP and extend bit durability. The novel bit has been applied in drilling Songliao Basin, China. The result shows that compared with the traditional diamond bit, the novel bit can drill 314% deeper hard formations with improvement of ROP by 127%. Therefore, this novel special hybrid bit technology provides a new efficient method for oil and gas exploration.