RIASSUNTO
Abstract
This paper describes a new intelligent well intervention performance system. One that contains a variety of sensors and electronics to gather critical downhole measurements, analyze them, and transmit them to surface for viewing in real time.
It confirms that many well intervention operations, especially those that get into difficulty, suffer from a lack of accurate information about true downhole conditions, and that actual downhole conditions in deep, high-angle wells differ significantly from what is indicated by traditional physical measurements taken at surface alone. The parameters measured downhole include RPM, torque, tension and compression, stick-slip, bending stress, dogleg severity, and many others.
Extensive field integration testing and early commercial deployment show how downhole tool performance information provides parametric information physically characterizing the true downhole environment. This real time information, never before seen at surface, demonstrates the potential to enable more efficient and more reliable well intervention operations while significantly reducing uncertainty and risk exposure.
Several case histories are presented where the smart tool was integrated into well intervention BHA's and operations were improved by a better understanding of what is really happening downhole.
Introduction
The current era of hydrocarbon extraction has brought with it an astonishing transformation in the extent and complexity of three-dimensional well path geometries. As little as thirty years ago, the vast majority of wells were of a relatively simple geometry, with the most complex having an initial vertical section followed by a straight tangent section that ended with a liner dropping into a vertical reservoir section. Workovers and wellbore intervention operations in these well profiles were also comparatively simple affairs, where the biggest challenge to evaluating the operation of service tools was overcoming sliding friction in the tangent section, a situation that was generally overcome by workstring rotation and selecting the midpoint of the up and down weights from the rig floor weight indicator. Over the last few decades, that case has changed dramatically. Well profiles are now much more complex and most definitely three-dimensional. In creating these complex well profiles, the drilling industry has developed some very sophisticated and reliable downhole technologies to operate in extremely hostile physical environments.