Stuck Pipe Prediction and Avoidance: Invocation of Basic Principle of Standard Methods, Pre and Post Sticking

Abstract

Stuck pipe in geothermal well drilling occurs when the drill string in the well bore cannot be pulled out without exceeding its designed working load. These incidents lead to non-productive time and unnecessary additional drilling costs. Statistics across the drilling projects indicate that stuck pipe is by far the greatest cause of lost time during drilling operations. Despite the progressive experience accumulated over the years in drilling operations, the stuck pipe occurrence is increasingly becoming a common phenomenon in accelerated drilling operations in Olkaria geothermal field. To free the stuck pipe is time consuming, costly, sometimes having to re-drill the well, or at the very worst losing the well bore itself. In well planning, the key to achieving objectives successfully is to design drilling programs on the basis of anticipated potential hole problems rather than on caution and containment. Understanding and anticipating stuck pipe problems, their causes, and planning solutions is necessary for overall-well-cost control and for successfully reaching the target zone. To exercise a holistic approach into this problem, stuck pipe avoidance team(comprising of well designers and implementers) need to be set up to develop and own strategies that can mitigate and reduce stuck pipe incidents. For continued improvement, it is highly important for the inter-disciplinary drilling operation crew to collectively, closely and proactively monitor step-wise drilling process with strict attention to every necessary detail. The team will be able to estimate the risk of occurrence of stuck pipe not only during well planning stage but also during drilling. Though it is good enough to solve a problem, it is always smarter to avoid it in the first place. This is the basic principle upon which this paper seeks to establish.