After a century of need, the drilling industry finally has the tools to properly analyze and optimize drilling fluid hydraulics. This is indeed fortunate, because most unscheduled trouble events in drilling are still hydraulics related. Emerging results from these tools and recurring field problems and challenges provide many good reasons to rethink drilling hydraulics and rheology, especially in critical-well applications. This paper is about the reasons that made the Top 10 list.
Real-time downhole pressure measurements, powerful / inexpensive computers, and quality HTHP / LT viscometers are among the most notable new diagnostic tools. Individually and collectively, they continue to remind the industry, for example, that downhole mud properties are different than those measured under surface conditions. Failure to compensate for significant differences in density, rheology, pressure loss, and other parameters can cause great difficulties, especially in wells drilled in HTHP and deepwater environments.
Items in this Top 10 list cover a wide range of hydraulics and rheological issues. Some focus on specific well conditions, some address new findings, and others dispel long-standing oilfield paradigms. All are practical and useful for solving common and unique well problems. Field examples are given where appropriate.