Research into the methods for ultrasonic testing of welds for steel-structure truss with connected lines

This paper makes research into the ultrasonic testing of welds for steel- structure truss with connected line according to the basic theory of ultrasonic testing and the practical experience of testing.And it uses reflective return wave of defect to analyse the character of the flaws that are in the welds with connected lines,and generalize regularity of some typical reflexive return wave of defects.It is also used to determine the character of other kinds of flaws in welds.