In line inspection is an effective technology to determine the conditions of the pipelines. Oil and Gas operators usually focus on corrosion which is the main threat to pipeline integrity. The purpose of this paper is to introduce the concept of corrosion acceleration which can be used with corrosion rate to determine pipeline condition and predict future status when 3 Inline Inspections are available. Corrosion features from the first two inspections are matched, and a corrosion rate is associated with each feature. The matching is carried out based on girth welds and relative distance as reported by the In Line Inspection. Similarly features from the second and third inspections are correlated and results in a second corrosion rate. Now that we have two Corrosion rates for the same feature between first two inspections, and between last two inspection, then we can measure the rate of change in the CR or what would be the new concept of corrosion acceleration. It is basically the difference in the CR over time between last two inspections and would be measured in mm/yr2 just like acceleration is measured in m/sec 2 for movement. An analogy will be made between the concepts of motion, velocity and acceleration and feature depth, corrosion rate, and acceleration. This approach will result in each corrosion feature being associated not only with a corrosion rate, but also with a corrosion acceleration. The acceleration is actually a method to determine if the mitigation activities in place are being effective or not (chemical treatment, maintenance pigging, etc.) Clearly if the acceleration is null or negative, then corrosion is being well controlled and not allowed to increase. If the acceleration is positive, then corrosion is not only being active but is increasing at a higher rate. This new concept shall be further studied and data from multiple inline inspections should be collected and analyzed to understand corrosion acceleration. This concept can be incorporated in Oil and Gas operators integrity management plans as a new technique to measure the performance of the corrosion mitigation activities for pipelines. Corrosion acceleration is a new concept to determine the rate of change of the corrosion rate for ILI reported corrosion features. It is therefore a novel approach to measure the effectiveness of the corrosion management activities between first two and last two ILI inspections
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