A major requirement to make drilling a cost-effective exercise is to maximize the performance to cut well delivery days (and therefore well associated cost) to the minimum. The area of interest experienced challenging startup. However, quick learning curve, and therefore a clear well–on–well improvement, is achieved while pursuing the technical limits of the downhole drilling equipment. A recent well having a record-breaking performance will be covered. The optimization efforts are reproduced on all wells aiming to surpase the newly established performance records. Offset wells were thoroughly analyzed to identify all potential areas for improvement and a detailed performance improvement plan was then prepared for all sections. Starting from surface sections (16-in and 12-in sections), clear road maps are followed taking into considerations each formation characteristics and previous real-time data for optimum parameters. Then moving to the 8-½-in combined vertical/curve/lateral sections, the most aggressive improvement plan is applied. This was achieved by adjusting the drilling strategies, revising the drilling systems used, and modifying the bottom-hole assemblies to reach reducing the number of runs required to clean-out previous casing and drilling the combined vertical/curve/lateral sections to one. Engineered solutions and continuous pursuit of the technical limits of the performance/directional equipment/systems succeeded to speed up the learning curve of the drilling performance, and then resulted in a continuous improvement along the journey of the development of the area of interest. The 16-in and 12-in sections are having back-to-back performance records. The work is continued with the consistent spirt of "limit is still to come" to maintain the good results and ensure repeatability (if not improving) on a well-on-well basis. Moving to the 8-½-in section, the one-BHA (bottom-hole assembly) approach succeeded and proved to be a major contributor to reducing well delivery time; it is now the standard practice on almost all new wells drilled, combining cleanout out previous casing and drilling vertical/curve/lateral sections to well total depth. Connection and surveying procedures were revised on all sections, and optimized to the minimum. This allowed cutting the average weight-to-weight connection time from 14 minutes to 7 minutes. As a result, the well delivery days’ duration was cut to 16 days on average from 24 days in the previous year until delivering a country record well with spud-to-total depth in 12.8 days, and spud-to-rig release in 16 days. This country record-breaking well will be discussed in details.

Long-extended reach drilling (ERD) well has become necessary to reach untapped resources. This paper will describe pre-planning, execution and post results of drilling ERD wells with large bore design of 12¼" as the main step out section and deploying 9⅝" casing on shallow TVD of 4,200’. Progressive increase of the ERD ratio and complexity from one well to the next was planned and executed till we reached the longest well deploying 8 KM of 9⅝" casing with 5.4 ERD ratio at 26,179' TD horizontally all the way. A learning curve was established on drilled wells while progressively increasing reach and complexity. Subject well was the longest of any well planned in the field by far. Success involved implementation of technically modeled engineered solutions and verified during execution. Operational procedures including but not limited to: proper planning and execution of well profile to ensure optimum placement in a specific formation and minimum side forces. Drilling and tripping procedures to ensure the lowest friction factor (FF) and allow drilling to target depth (TD) with optimum rig capability. Engineered solution for casing running technologies, which involved rotation and conventional running and floatation. The longest ERD well was drilled to 26,179' TD with field ROP record in 12¼" hole section, maintaining very good hole quality proved by smooth bit trips out of hole and the final trip at TD on elevators. Hole cleaning and fluids strategy was developed and executed efficiently to measure FFs as low as possible for successful 9⅝" deployment. Engineered solution was proposed for 9⅝" deployment and was successfully trial tested on a shorter well to validate simulations. Casing rotation FFs came close to the modeled FFs. The 9⅝" Casing was deployed to bottom as planned and the cement job was performed successfully. Various records were achieved: the subject well achieved the deepest 9⅝" horizontal casing, the deepest 12¼" horizontal at TVD shallower than 5,000'. The longest 12¼" horizontal open hole at TVD shallower than 5,000' with section footage of 16,164'. The 9⅝" casing was deployed as a long string, eliminating the cost and challenges of a liner hanger and the need for a future tieback and also keeping hole sizes available for main and contingency sections to drill the reservoirs ahead. In addition to existing developed procedures and practices for ERD wells, subject well was dealing with the challenge of drilling a long 12 ¼" hole with a torque limitation of 30K lbsf.ft on TDS, and 4200 psi on surface equipment, and running the longest casing horizontally at such a shallow TVD, which is being done the first time globally. The success proved that challenging ERD wells can be drilled with optimum investments on rig capabilities.