When employing ultrasonic phased array sector scanning technology to detect defects in the lead seal of cable terminals, the irregular surface of the lead seal often prevents complete contact with the probe. This misalignment results in imaging issues such as noise, artifacts, and discontinuous defect representations. To address these challenges, a novel method for enhancing the quality of ultrasonic images of lead seal defects has been developed. The process begins with filtering and denoising the fan-scan image data of lead seal defects gathered from phased array equipment. Subsequently, the denoised data undergoes enveloping via the Hilbert transform, followed by interpolation using the Lanczos method. The refined image data is then subjected to angle correction before final imaging. Experimental comparisons demonstrate that this method effectively eliminates noise and artifacts from the fan-scan images of lead seal defects. Specifically, the signal-to-noise ratio of the threshold filter image surpasses that of the median and mean filters by 6.28 dB and 6.07 dB, respectively. Additionally, the continuity of the defect edges is significantly enhanced. These improvements in imaging quality facilitate more accurate detection and quantification of lead seal defects.
