Publications

Medco Energi-Oman successfully applied a new technique to drill horizontal SimSim Gharif Field wells to overcome challenges and difficulties when running in and pulling out with drill pipe and casing through the Mesozoic Clastic formation (MC). Previously, the 12 ¼” section was drilled vertically and 9 5/8” casing was set at the Natih C Carbonate above the MC. The 8 ½” section contained the buildup and high dogleg severities through the MC. Long exposure, high angles, high curvature, long open-hole section and slide-drilling caused MC sand to cave-in, which led to stuck pipe or casing in SMPG-3/4/5 wells. The improvement was to kick-off shallower in the top section, and then drill the MC in the 12 ¼” section in rotation mode, and then set 9 5/8” casing below the MC. Also, drilling fluid hydraulics were improved by adding glycol to increase lubricity and improve shale inhibition so running in/out drill strings and casing was smoother. Finally, a Casing Running Tool, Reamer Shoe and rigid centralizers were used, which allowed casing to always reach the intended depth.