Abstract: With regard to the detection of tranverse flaws for the inside and outside walls perpendicular to pipe axis,ultrasonic test textbook and relevant test standard only describe the reference block of sensitivity adjustment and show the lack of the calibration block for scan baseline calibration and K value testing of ultrasonic shear wave angle probe,which results failing to detect the steel pipe tranverse defects.This article,by using the principle of equivalent test block,dissertates upon the methods for scan baseline calibration and K value testing of ultrasonic shear wave angle probe when the tranverse defect of steel pipe is tested.