MPD - Drilling Optimization Technology, Risk Management Tool, or Both?

摘要

Managed Pressure Drilling (MPD) was introduced to offshore drilling decision-makers in 2003. To garner industry attention, it was taught in a “let me show you the money” style with a focus upon its ability to mitigate the types of drilling challenges that often manifest excessive drilling non-productive time (NPT), high mud costs and failure to reach the total objective with large enough hole for optimum well productivity. Hundreds of offshore applications have now been safely and effectively practiced from all types of offshore rigs. Compared to offset wells, NPT and mud costs are reduced significantly. Otherwise technically or economically un-drillable prospects have been drilled, increasing recoverable reserves in operator’s business units. There have been no reportable well control incidents where the root cause has been attributed to the technology itself or failure of its key enabling equipment. All operators’ business units who have practiced MPD, however conservatively as an early adopter, appear to have no reservation about applying it again on challenging prospects that may benefit from its hallmark – optimizing the drilling process by precise management of the wellbore pressure profile. There is no doubt that MPD has “showed the money”. However, its track record has demonstrated other strengths of significance in today’s drilling environment. MPD is being recognized as a risk management technology applicable to complex prospects whose drilling hazards, if not mitigated with best available technology, increase the risk of a well control scenario developing and time for “something else to go wrong”. Un-mitigated drilling hazards may also contribute to the well being over budget and behind schedule - a human factors climate which tempts short cuts and cost savings later in drilling program and plugging & abandonment (P&A) operations that are not peer-reviewed or thoroughly vetted for added risk and potential HSE consequences. This paper will provide evidence in the form of case studies that suggest the industry consider the positive effects on drilling costs and increased recoverable reserves as welcome by-products of MPD applications but not necessarily the primary objective of its application.