High corrosion rates were expected in the production tubing in Tullow Oil’s Bangora Field, and this was confirmed by successive downhole surveys. Comparison of actual corrosion losses as shown by the survey data and corrosion modelling predictions made using Wood Group Intetech's Electronic Corrosion Engineer (ECE®) software turned out to be in very close agreement.

Corrosion modelling was then used to estimate the future corrosion penetration. Because of the excellent agreement between the actual and the calculated corrosion damage in the past, there was sufficient confidence to extend the period between future caliper surveys, saving several million dollars. Tubing replacement was deferred based on the modelling predictions, thus maximising the useful life of the string. At the same time, the combination of inspection and modelling has reduced the risk of an unexpected tubing leak arising, resulting in an unplanned shut-in which would have significant costs in deferred production and loss of revenue

For more detail , see Billingham M. A., King B. (Tullow Oil Ltd) , Murray A. (READ Cased Hole Ltd) ; ”Maximising the life of corroding tubing by combining accurate multi-finger caliper data with corrosion modelling” ADIPEC Nov 11-14 Abu Dhabi, 2012; SPE 159484-PP