One of the most frustrating and costly aspects of any wellbore intervention operation is when little or no progress is made during a trip in the well and tools are returned to surface showing no visible signs of performing work. Conversely but equally frustrating is when a downhole tool becomes worn or damaged beyond its useable life and the operator continues to try to make progress based on readings from traditional surface-based indicators and gauges. These situations are becoming more common as wells become deeper, more complex and technically challenging to intervene.
To address these problems, a "smart intervention" system has been developed that provides a new level of process control to the operator while intervention work is being carried out. The system incorporates a short, modular MWD-style sensor sub that is integrated into the bottom hole assembly (BHA). Measurements such as weight on bit, torque, RPM, bending moment, vibration, annular and bore pressures are gathered downhole to provide a clearer picture of what is occurring at and around the downhole tools. Information is then transmitted to surface using mud pulse telemetry and viewed on a rig floor monitor. The system allows the operator to make informed decisions and take immediate action to optimize the intervention being performed.
This paper discusses initial system integration and field testing, benchmarking and analysis, as well as results of, and lessons learned from, early field case histories. The tests and field runs demonstrate the potential of this systems approach to provide economic benefits through significantly improved efficiency, reduced uncertainty, better reliability and less wear and damage to downhole tools and equipment.