The Touchstone 3 is a new thickness gauge able to measure steel through coatings using only the first back wall echo. The patented, revolutionary approach overcomes the widespread problems historically associated with obtaining repeat echoes from pitted or heavily corroded reflecting surfaces.
Until the introduction of the Touchstone 3 thickness gauges measured through coatings by either employing a multiple echo technique (the method varies between manufacturers) or simply recording one total transit time through the coating and steel resulting in erroneous readings. The Touchstone 3 uses a combination of ultrasonic and coating thickness gauge technologies. Both parts of the combined sensor supply information to the gauge microprocessor and the individual coating and steel thicknesses are shown on the dual display.
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