Enhanced Horizontal Well Drilling in North Kuwait Boosts Drilling Phase and Achieves Wellbore Cleaning Goals

Abstract

Promotion of horizontal well drilling started with inflow control device (ICD) completion to boost the hydrocarbon production as per the KOC 2030 strategy. Drilling these wells revealed many technical issues leading to stuck pipe due to improper hole cleaning. The rate of penetration (ROP) in the buildup and lateral sections was erratic. Drilling a pilot hole and performing pipe-conveyed logging runs were the main factors contributing to excess rig time. It was observed that drain hole cleaning methods and drilling time optimization needed to be improved. These factors increased rig time by about 40 while drilling many horizontal wells in the North Kuwait (NK) horizontal operation, adding significant costs to the well budget. While drilling these horizontal wells, well design was optimized and the drilling team applied the optimized design that increased hole-cleaning effectively, improved ROP and reduced the logging time. The 6⅛-in. and 8½-in. motorized rotary steer-able systems (RSS) and bottomhole assembly (BHA) systems ran for the first time in Kuwait, drilling 8½-in. build section from Mutriba to the Upper Burgan top formation and 6⅛-in. section in Mauddud carbonates has dynamically avoided down-hole tool failures, doubled the average ROP, and reduced non-productive time (NPT). The pilot hole section was designed and drilled in two phases. In the first section a gamma ray tool identified the formation tops. The second section (zone of formation interest) was then drilled using an 8½-in. tool with a triple-combo RSS BHA. This approach reduced the extensive wireline or tough logging condition (TLC) runs and increased ROP by slimming down the borehole size. The hole-cleaning method was modified by combining pumpout techniques with heavy-weighted pills (MW+2 ppg). This technique was used in horizontal wells, resulting in reduced drilling time and well cost.