石家庄工务段钢轨探伤组根据我段铁路地处山区的特点,以减少探伤工人劳动强度,易于上下道为目的,1974年以来,试制成功了SG-1型数字式超声波钢轨探伤仪,1975年,在1型仪器的基础上,加以改进,制成了SG-2型数字式超声波钢轨探伤仪(图1),这种仪 According to the characteristics of the railway locating in the mountainous area in Shijiazhuang, the SG-1 digital ultrasonic rail flaw detector was trial-manufactured successfully since 1974 in order to reduce the labor intensity of the testing workers and to be easy to get on and off the road. In 1975, On the basis of 1 type of instrument, to be improved, made SG-2 digital ultrasonic rail flaw detector (Figure 1), this instrument