Statistical Analysis of Corrosion Losses of the Main Oil Pipelines Linear Part

Abstract

The article analyzes the recurrence of defects and damages on main oil pipelines, in particular corrosion, and the problem of ensuring the reliability of steel structures and pipelines used in oil and gas complexes. It has been found that the most common and dangerous operational damage to the linear parts of main oil pipelines is corrosion damage, which has the character of cavities with random depth and length, as well as random placement along the length of the pipeline. A reliable means of detecting corrosion damage is in-line diagnostics, which allows measuring the depth of each corrosion cavity with high accuracy and determining its location along the pipeline length. The length of corrosion damage is represented as a random variable with a logarithmically normal distribution law, independent of the random variable of corrosion depth. The preferred probabilistic model is the sequence of maximum corrosion depth values, which provides a probabilistic description of corrosion damage sufficiently accurate for reliability assessment and is consistent with the accepted repair technology, in which entire sections of the pipeline are replaced in severely damaged areas. Using the statistical analysis, the corrosion effects were studied at each of the selected sites as a result of diagnostics inside the pipe, and attention is drawn to the need to research and improve scientific, technical and technological developments in the field of corrosion and mechanical resistance of metal structures. The results obtained are an important contribution to the development of technical and design measures to improve the efficiency and reliability of oil and gas complexes.