Background: Flow Accelerated Corrosion（FAC） leads to wall thinning（metal lose） and strength reduction of steel piping.Piping degradation due to FAC can affect plant reliability and may cause serious accident.Purpose: This paper sets up the analysis and assessment method for the wall thinning due to FAC.Methods: This method mainly bases on local metal loss Level 3 of API 579.Using FEA software ANSYS develop parameterized models

including straight pipe

elbow

reducer

etc.The models can be expediently defined geometry and material parameter

load and constraint condition.Furthermore

the real thickness model of the pipe can be established by using the data of in-service inspection.Results: With the limit-load analysis method to assessment the strength of piping

the method achieved local metal loss Level 3 assessment effectively.Conclusions: Using this method to establish the true model of pipe wall thickness

can improve the accuracy of analysis of pipe wall thickness thinning evaluation.