During the rolling of seamless tubes, the tube wall thickness is of particular importance for a quality assurance system (QAS), since tubes rolled with excessively thick walls equate to a material loss. In order to minimise this loss, the deviation between nominal and actual wall thickness must be measured and corrected as early as possible in the production process. There are a number of possible methods for measuring the thickness. The most important of these are described and compared with one another below. The latest development, Lasus Multi-Scan, is based on the laser-excited and laser-detected ultrasonic measuring principle that offers a number of technical benefits for the wall thickness measurement and forms an ideal basis for a QAS.

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