Electrical Resistance (ER) probes are used as the central corrosion rate monitoring process to evaluate the effectiveness of Vapor Corrosion Inhibitors (VCI). The dependability of ER probes has become one of the major resourceful instruments being used to periodically examine corrosion rates underneath Aboveground Storage Tanks (AST). There are many approaches to detect corrosion levels underneath such tanks. One that is reliable and trackable is using a data logger to take readings on ER probes continuously and analyzing the data using a graphical method that thoroughly shows a linearized comparison of metal loss over time. The analytical range of check values is important during the analysis process with regards to making sure the reference points are standardized and within a good variant. A linear trend is used to quantify the corrosion rate and performance of VCI over time. The decision to either inject or reinject VCI are usually made in conjunction with analyzed data from the moving point average method that shows a proportional reduction in metal loss and inhibitor efficiency beneath the tank. Case studies on VCI monitoring in different geographical regions are outlined in this paper.


Aboveground storage tanks (ASTs) are assets that contain valuable goods for the oil and gas industry.1 Consequently, monitoring and preventing loss of containment and extending the service life of those assets is a priority for the abovementioned industries. To monitor the degradation process of the tanks, ER probes are typically used to determine the corrosion rates.2 Corrosion rates can be used to forecast the service life of an asset by estimating the time at which the degradation reaches a critical thickness of the tank. If the corrosion rate is such that the critical thickness is expected to reach below the expected service life of the asset, the lifespan can be extended by corrosion mitigation methods.3 Cathodic protection (CP) and vapor corrosion inhibitors (VCI) are the most used method to mitigate corrosion in ASTs.4

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