Although some wells from other exploration and development projects in onshore Iran have been finished before, there is a big challenge for North Azadegan field to drill 58 wells in less than 3 years, with more than 8 upgraded 2000HP rigs in the marshy area under the economic sanction surrounding according to strict requirements of Buy-Back development contract. Moreover, operation area with average 2m water depth, about 2000m directional length section accompanied with narrow mud density window, violently fluctuations in rock strength and complete losses during cementing have also contributed to increased NPT with associated high costs in N.Azadegan field. This paper will focus on main drilling problems and integrated technique, as well as the experience and lessons learned in implementing the Iran’s development project. Specific key tactics discussed include: maximum utilization of Iranian contents, cluster well pad and auto-move rig system, bit selection and modified drillable float& shoes accessories, losses and overflow prevention measures, surface back pressure performed immediately after cement placement in a few time, a clear process for capturing the best practices and lessons learned. An integrated approach was formed to decrease single well duration with less money ahead of schedule which was fixed 120d in Buy-Back contract. On the first 10 wells, average drilling performance was improved 57% and saved millions of U.S dollars with key solutions to overcome drilling challenges.
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