The automatically thickness measurement method for pipeline corrosion detection of ultrasound

which has the significant features as large amount of data and much interference

is required high adaptability.However

many algorithms for pipeline corrosion detection of ultrasound have many defects

such as high misdiagnosis rate

low accuracy or more time-consumed.For solving this problem

the two-step method which is based on FFT is proposed in this paper.Firstly

twice FFT algorithm is researched for solving high misdiagnosis rate problem.Secondly

the improved twice FFT method is presented to solve the low precision of traditional twice FFT method.The theoretical analysis and experiments shows that the presented method has high precision and low misdiagnosis rate which is the same as FFT and twice FFT respectively.The automatically thickness measurement for pipeline corrosion detection of ultrasound can be realized by this method.