Corrosion occurrence in the oil and gas production system is an example of an unavoidable problem. This problem is caused by the presence of water and corrosive material fraction along with the produced hydrocarbon. On the way from the reservoir to the surface, the mixture between water fraction and the corrosive substance might adhere to the wall of conduit steel pipe (e.g. tubing, casing, and flowline) and can lead to corrosion on the wall. The corrosion problem can have a major impact on the economics of the production because the cost of production equipment is relatively expensive and workover operation is very costly. Therefore, planning and mitigation for a better production system need to be performed, so that the rate of corrosion can be controlled, and its economic impacts can be minimized. The purpose of this study was to create an integrated model of the corrosion rate calculation on the tubing by the Petroleum Engineering Study Program of Bandung Institute of Technology (ITB). Several terms related to the production process were considered in this model: the characteristics of the produced fluid, flow regimes, pressure and temperature conditions along the tubing, the trajectory of the well, the type of tubing material used, and the use of inhibitors. The model was developed from the model developed by C. de Waard, Liane Smith, and Mike Billingham. The corrosion rate calculation model was then validated using field data and the results were compared with the result from industrial commercial software, Electronic Corrosion Engineer (ECE®). The corrosion rate calculation model were able to predict the rate of corrosion in oil and gas wells accurately. A software-based system was created based on this integrated and accurate proven model. By using this software, the production system can be simulated and tested for various conditions, and then the result can be compared with each other to obtain the optimum fluid production rate with minimum corrosion rate. In addition, this software is capable to determine the most suitable tubing material which will be used in a given production environment and condition.
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