Multiple Deployments of Hybrid Drill Bits with Optimized Drilling Systems Prove Enhanced Efficiency in North Kuwait Development Wells

摘要

In the prolific North Kuwait field, the 16 inch intermediate vertical section is typically drilled with Tungesten Carbide Insert (TCI) drill bit [445 IADC] and rotary assembly. The TCI average Rate of Penetration (ROP), through approximately 4,800 feet of limestone, sandstone and shale, is 38.7 feet per hour. Given the operator's target to reduce drilling time and minimize the North Kuwait well cycles; the hybrid drill bit was proposed to raise ROP performance and save drilling days per well. The main challenge was to significantly reduce drilling time and enhance the cost-per-foot of the application with the new hybrid drill bit. In addition to providing smooth torque fluctuations, similar to that of the roller cones drill bit. A specialized Drilling Application Review Team (DART) from the service provider implemented an optimization process to achieve the aforementioned targets. The hybrid bit design has been revised and upgraded to best-fit the interbedded carbonates application. Bottom Hole Assembly has been modeled and optimized by the cross-functional engineering team and the client to ensure best torque response while drilling. Moreover, a detailed formation drilling analysis has been conducted to accurately anticipate hybrid bit ideal case. The optimized hybrid drill bit set the highest ROP record, at 80 feet per hour in North Kuwait achieving 107 percent improvement from offsets’ average performance. Moreover, the optimized design delivered 2 and a half days savings when compared to field offsets by conventional technology. The selected system generated smooth torque response and hence high energy efficiency. This success has been repeated over multiple wells in North Kuwait project; proving consistency in technology value.