Engineering Application of Miniature Specimen Sampling Method on FFS Assessment of Corrosive Pits of In-Service Pressure Pipeline

This paper aims at in-service inspection of a petrochemical companies’ process pipeline which was found to have corrosive pits during a regular periodic inspection. By adopting miniature specimen sampling method, some (size of 12 × 12 × 1.3mm) sheets were obtained in the pipeline. Yield strength and tensile strength of the material can be obtained by small punch test method. Fitness-For-Service (FFS) procedures based on different standards are performed on the corrosive pits and the sampling areas to assess their safety. The research shows that it is feasible to obtain the actual mechanical properties of the material in the field by using the miniature specimen sampling method. The method mentioned in this paper is of guiding significance for FFS assessment on in-service pressure pipelines.