Novel Drill Bit Materials Technology Fusion Delivers Performance Step Change in Hard and Difficult Formations

Abstract

Abstract Ever evolving drilling performance requirements dictate bits drill wider ranges of lithologies while offering improved efficiency and reduced NPT. These performance requirements necessitate compatible drill bit technologies. As lithologies associated with these drilling objectives tend to be harder and more abrasive; the need for adaptable, durable, and efficient drill bit designs is intensified. With these challenging applications / objectives, Polycrystalline Diamond Compact (PDC) technologies are pushed to their material limits. These limits emerge as failures in PDC thermal fatigue, abrasion, and impact damage. Due to the absence of state-of-the-art drill bit material technologies compatible with achieving these drilling objectives, multiple trips are commonly required. Often, this translates into the use of non-PDC bits (Rolling Cutter and Impregnated) to complete challenging sections. As efficiency is hindered by bit type and increases in non-productivetime due to multiple bit trips, operators incur significant cost while drilling these intervals. New drill bit technology capable of drilling these lithologies and performance requirements is unmistakably needed. This paper describes the development of novel drill bit technology aimed at this requirement. This technology is born through the fusion of existing bit technologies; Fixed Cutter and Impregnated Diamond, and a unique design philosophy providing greater versatility in drilling a wider range of harsh lithologies, not typically drilled entirely with PDC bits. This novel design philosophy includes optimized cutter placement and exposure of diamond impregnated mix applied in critical areas of the bit. This project was initially targeted at the Sub-Saharan region in the Congo, where the existence of conglomeratic intervals still represents a challenge to reach TD in a single run for sections with high clonglomeratic percentage. In its first trial, the new technology hybrid bit drilled 300% more interval than the benchmark with 34% improvement in ROP, in comparable sections with similar conglomerate content. Subsequent runs have resulted in dramatic savings due to reduction of trips as well as improved ROP. This technology has provided the industry step change in performance and decrease in non-productive time.