Managed Pressure Drilling (MPD) has been deployed in Vietnam for six (6) years since 2007 to address a number of drilling and reservoir challenges, and has delivered considerable success in many cases. Twenty five (25) separate projects have been performed over the six (6) year period, in a range of formations and with different types of rigs. The main application of MPD Technology has been in the following reservoir and formation types where the challenges are being encountered: granite basement, fractured and vugular carbonates, High Pressure High Temperature (HPHT) and over pressured clastics. MPD has not been applied as yet in deepwater, but its application is being viewed with interest by operators in Vietnam planning deep water operations, following its successful deployment in other regions of South East Asia. The types of rigs on which the technology has and is being applied are all offshore, and include Jack-Ups, Semi-Submersibles and a Platform rig supported by Semi-Submersible Drilling Tender Assist barge. The paper will examine and discuss the different procedural approach of MPD Technology used today including Constant Bottom Hole Pressure – Equivalent Circulating Density (ECD) management, Early Kick Detection, and Pressurized Mud Cap Drilling (PMCD). MPD has mainly been used in reservoir sections, but by no means exclusively, for example in carbonate loss zones which may or may not contain gas, for Rate of Penetration (ROP) gain and ECD management in intermediate hole sections. Three (3) case histories will be presented within the paper addressing the different applications and formations in which the technology has been applied in Vietnam. This includes achieving an additional 800 meters of a granite basement reservoir section, reducing the fluid losses, improving ROP, reduction of Non – Productive Time (NPT) and post drilling clean up, by 60 – 70%, compared with previous wells in the field. The drilling of HPHT and over pressured clastic formations with an extremely narrow kick – loss tolerance, where there is a high risk of fracturing the formation or inducing a serious kick, if the hydraulic profile of the well is not successfully managed. The pre-planning, engineering, equipment utilized, and adaption of the drilling rig to facilitate the successful deployment of MPD Technology will all be discussed, to clearly demonstrate what is required to deliver a successful MPD project and the well objectives.
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