超声标准规定,采用超声横波一次反射法检测焊缝时,探头移动区大于或等于1.25P。按此计算方法确定的探头移动区,超声声束无法将检测区完全覆盖,一次反射波存在漏检的可能。本文依据检测区、一次波与一次反射波对应的水平距离、探头长度之间的几何对应关系,对探头移动区的计算方法进行了论述。 Ultrasonic standards, the use of ultrasonic shear wave reflection method when testing the weld, the probe moving area greater than or equal to 1.25P. According to this calculation method to determine the moving area of ​​the probe, the ultrasonic beam can not completely cover the detection area, there is a missed detection of the possibility of a reflection. In this paper, the calculation method of the moving area of ​​the probe is discussed based on the geometric correspondence between the horizontal distance of the detection zone, the primary wave and the primary reflected wave and the length of the probe.