BS EN ISO 17640 contains standard ultrasonic inspection techniques for ferritic steel welds. The techniques in general include scans with different angles from either side of the weld.
The minimum thickness noted in this standard is 8mm. However there are an increasing number of applications involving smaller thicknesses (e.g., containments) and these cannot strictly be inspected by these methods.
This paper describes a series of experiments of conventional ultrasonic and phased array testing on thin butt welded sections with simulated flaws using the procedures described in BS EN ISO 17640 and BS EN 13588 but allowing the use of high frequency and small probes easily available in the market. The results show that the procedures of BS EN ISO 17640 can be adapted in this way for detection scanning and sizing for thicknesses down to 4mm.