Abstract: Combined with the engineering application data, the results of coarse-grained weld quality inspection by full focus phased array ultrasound and double crystal focused longitudinal wave angle probe ultrasound are compared and analyzed. The signal-to-noise ratio data, defect detection ability data and scanning coverage ability of the two technologies are obtained. It is pointed out that the full focus phased array inspection technology is characteristic of large coverage, which can reduce the scanning times and improve the detection speed, and thus decreasing the rate of undetected defects.