Risk Assessment of Dry Sweet Gas Pipeline via a New Methodology for Corrosion Risk Assessment of Transmission Pipelines

"Risk" is a mathematical expression obtained by multiplying the probability of an event occurring by its consequences. For many years, a variety of qualitative, weighting, and scoring methods have been used in the pipeline risk assessment in the industry, but the output of these methods has been qualitative, while in areas Scoring and indexing methods are not used to make reasonable conclusions. That is why the development of a methodology whose results are more accurate, applicable and more cited is very interesting. In this study, a new methodology was developed to evaluate the corrosion risk of gas pipelines where the probability of failure due to soil side corrosion and internal corrosion threats is presented as a function of the time to failure. The consequences of a disability are also determined by the nature of the fluid and the environment affected by the leakage, and ultimately the risk of failure is presented in the form of "Outcome per unit of time". To evaluate the applicability of this methodology, a 10-km segment of a 30-inch pipeline was evaluated by the present methodology. The results showed that the highest risk of this pipeline was for the parts that were encased inside the casing and the risk was 15096.44 $/ year.