Structural Health Monitoring of An Offshore Platform Trend of Corrosion and Marine Growth With Predictive Maintenance

Abstract

Nowadays, there are a lot of oil and gas exploration activities all over the world, especially offshore. Oil and gas production itself has many supporting factors in the production process, of which one of them is the offshore platform. Over time, the offshore platform will experience a degradation in strength from the initial design, therefore offshore platforms need to carry out appropriate inspection, maintenance and repair (IMR) programs so that the offshore platform does not reach critical conditions and disrupt the oil and gas production process, resulting in significant losses and not achieving the planned production rates. The offshore platform design is a combination of steel structure and other materials, methods, and loads that are initially worked at the port, such as wave loads, currents, and several other parameters such as gravity, wind, and earthquake. Most of the offshore platforms that currently exist (worldwide) were made in the period of oil investment that developed between 1970 and 1980, thus, the platform's age has now reached 40 to 50 years (El-Reedy, 2012). This research data based on a platform in the Makassar strait between the islands of Kalimantan and Sulawesi. The method used in this research is the platform's design, data observation, data analysis, data processing, and statistical multilinear regression analysis. This research is investigating the degradation trend of the offshore platform and predicting the future of potential failure because of corrosion and marine growth. After the platform encounters degradation over several years, it will decrease the service life before the degradation starts to matter. The results show after data processing that, offshore platforms encounter degradation over several years, and it is presented by a graph containing the condition trend over a multi-year condition because of corrosion and marine growth, and its effect towards unity check (UC) that define structure health. Unity check value produced from allowable stress versus capacity. In this research, structural health monitoring is predicting the potential failure of the platform towards its UC effect of corrosion and marine growth, with a max of the UC value is 0.8 because its a critical value. The failure of the structure possibly would have an affect on the cost-effectiveness. Therefore it is necessary to predict when the structure will fail so that the costs used are effective. Unfortunately, there is no core data for the environmental changes every year at the platform, so the model's equation does not include environmental conditions.