A New Multi-Level Assessment Procedure for Corroded Line Pipe

A new assessment method to predict the failure pressure of corrosion defects in line pipe has been developed. Comparison to an experimental database shows that this new assessment procedure has advantages over existing techniques. The implementation of this method is proposed in a multi-level assessment procedure. The assessment levels are organized in terms of increasing complexity, with Level I being a lower bound solution and requiring only the maximum defect depth. The new assessment method requires detailed corrosion geometry measurements and is proposed as a Level II. Three dimensional elastic-plastic finite element analysis is proposed for the Level III. These methods assume the true stress-strain curve of the material is known, which can be determined from uniaxial tensile tests. When these material properties are unknown, the currently accepted codes are suggested for defect evaluation.