To solve the problem that it is difficult to detect the welded joint in the pipe confined space

a phased array ultrasonic testing method is proposed. CIVA simulation software is used to optimize the parameters of phased array ultrasonic testing probe and transducer

and the phased array ultrasonic testing technology in confined space is developed. Moreover

the phased array ultrasonic testing and X-ray testing are simulated and compared. The simulation results show that

the phased array ultrasonic testing method designed and developed in this paper can effectively detect the defects

and the defect location and amplitude response law of each defect are similar to the measured value. Compared with X-ray detection

the phased array ultrasonic testing method has basically the same result in defect characterization

and has advantages in the measurement of the defect depth and height

but there is a blind area less than 5 mm on the upper surface. For the surface and near surface blind area defects

increasing the detection position of the phased array ultrasonic probe or using other methods should be taken as supplementary detection technology.