Acoustic emission (AE) field application:testing of aboveground storage tanks (AST) for corrosion and leakage

摘要

A new testing technique for corrosion and leakage testing of the flat bottoms of atmospheric,aboveground storage tanks (AST) with acoustic emission (AE) was developed in the frame of an EC funded project [1].Frequency domain based pattern recognition is used to identify the source mechanism of the found AE sources located at the tank floor.The basics of the applied method and the testing technique itself are outlined as well as results of performed tests are given together with statistical numbers regarding the grading of tested tank floors.Conventional non-destructive testing (NDT) of tank floors relies mainly on visual testing and wall thickness measurements and therefore reflects the past service periods of the tank in total.On the other hand AE allows monitoring of the active processes taking place at the time of test on the tank floor at conditions similar to normal tank service.The combination of both techniques leads to a complementary view of the tank floor condition,taking advantage of both approaches:determination of the total degradation of the tank floor and monitoring of the actual degradation processes taking place under current service conditions.