Evaluation on the Corrosion Rate of Pipeline with Analytic Hierarchy Process and Fuzzy Comprehensive Evaluation Method

This paper puts forward a new kind of model to evaluate the pipeline soil corrosion to determine the corrosive factors for long-distance buried transmission pipelines. The grey conjunction method is used to determine the sequence of soil corrosive factors, also including the improved analytic hierarchy process to analyze and determine the weight of each factor. Finally, the authors establish a subjection function along with fuzzy comprehensive evaluation method to evaluate the corrosive condition of pipeline in service. In practical calculation, five main influencing corrosive factors are taken into account, including soil resistance, oxidative and deoxidized electric potential, pH value, water content and salt content, and five corresponding evaluation grades such as "very serious, serious, intermediate, light, terribly low" are established. The corrosive condition about 8 pipeline check points is evaluated, and finally the pipeline evaluating grade obtained, which is the same as the local fact. According to practical calculation, this method can be used in evaluating the soil corrosive condition of pipeline, and a scientific foundation for in-time maintenance and replacement of pipeline.