利用超声横波在瓷绝缘柱中折射角为75°～84°的上扩散角检测瓷绝缘柱表面缺陷，克服了常规用爬波探头灵敏度低的弊端；对超声波探头角度、尺寸、接线柱位置以及瓷绝缘柱试块进行了相应设计，为瓷绝缘柱的检测提供了检测方法和判伤依据。

The surface defect in porcelain insulation column is detected by the upper diffusion angle of 75°～84° of ultrasonic shear wave in the porcelain insulation column. This method can overcome the low sensitivity of probe. The article describes the design of both angle and size of ultrasonic probe, wiring terminal position, and test block of porcelain insulation column, which provides a method for the detection and a basis for defect judge of porcelain insulation column.