A SYSTEMATIC APPROACH TOWARD SELECTION OF COST-EFFECTIVE AND CORROSION RESISTANT MATERIALS AND CORROSION INHIBITION AND PROTECTION METHODS BY USING CORROSION PREDICTION MODELS

摘要

A methodology was developed to identify and choose the most cost-effective material and also appropriate remedial corrosion inhibition and protection methods by using 4 reputable corrosion prediction models in dry and wet oil & gas pipeline containing CO_2 with and without H_2S. The importance of the corrosion allowance factor for the basic design stage, initiated this project as an active study in NEC~((2)) in early 2008. Observed discrepancies in the predicted corrosion rates by different corrosion prediction models for identical conditions, aimed the group to develop a methodology that with compromising the limitation and capabilities of each models, concludes the most reliable approach toward corrosion rate prediction in the company's pipeline projects.Methodology was initially based on; a) Identifying the features, capabilities and also limitations of each corrosion prediction model b) Identifying and prioritizing the critical variants in corrosion rate prediction for the given environment (Sweet / Sour)Thereafter, according to the mentioned steps and the project's restrictions the most cost-effective remedy action for each critical corrosion rate's variant was selected by cost-benefit study. Ultimately, this approach has been implemented in company's current projects and results appeared to be satisfactory enough.