Non-destructive testing (NDT) of bar stock is subject to constantly increasing demands concerning the quality of the test. This applies to bright precision steel and special bar quality (SBQ) levels as well as to hot-rolled black steel bar and wire, which often are used as a semi-finished product for cold-drawn bars.
Until the mid-2000s, eddy current inspection only was still sufficient to meet the quality requirements of the automotive industry. Today, non-destructive ultrasonic testing has become a standard method for most material qualities.
To avoid that the increased inspection requirements affect the profitability of the products, automated phased-array ultrasonic testing of long steel bar and wire stock became part of the standard inspection process.
In contrast to conventional test systems, ultrasonic phased-array inspection systems consist of fewer individual parts, since the direction of the sound is no longer generated by mechanical adjustment of probes, but electronically. This also eliminates the need to manually set the ultrasonic incidence angle, which requires a certain amount of operator skill and is time-consuming.
Phased-array test systems require significantly less maintenance, have a higher level of availability and, at the same time, place lower demands on the personnel than conventional ultrasonic test systems, since all settings of previously prepared data sets are made fully automatically and are reproducible.