Ultrasonic spatial imaging and flow measurement through casing for assessment of cement condition and well integrity

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Well integrity management and risk evaluation is a global challenge. Statistics from three independent sources demonstrate that there are well integrity issues in 45 %, 34 %, and 18 % of the wells in the Gulf of Mexico, North Sea UK sector and North Sea N orwegian sector, respectively. On average about 38 % of wells worldwide are underperforming due to integrity issues, and a conservative estimate indicates that the total lost revenue is over 1 billion USD per day. No existing tools are able to confident ly quantify the risk of uncontrolled discharge related to annular integrity, which is the second most important source of well issues, constituting 20 % of all well integrity issues worldwide. A new tool with capability to pinpoint the location of failure s will provide facts for the well owner to decide whether to plug the well or to perform measures to repair it, as well as which measures that will be most effective during all stages of a well's lifetime. Through research on penetrating ultrasound techn ology we propose to develop a well intervention tool capable of providing spatial images of the cement condition behind casing - within the first annulus, as well as detecting and quantifying fluid flow behind casing in the event that barrier integrity ha s failed. The information obtained with a new tool would give a massive potential for increased revenue both through more effective interventions and the possibility to reopen wells that have been shut in due to annular integrity issues. Additionally, red uced safety hazards and risk of uncontrolled discharges will be a benefit for the society at large.