VERFAHREN ZUR UEBERPRUEFUNG DER WAERMETAUSCHERROHRE IN EINEM WAERMETAUSCHER

摘要

A process is disclosed for inspecting heat exchanger tubes in a heat exchanger. Heat is transferred from a first medium to a second medium that is isolated from the first medium in a gas- and liquid-tight manner, and the heat exchanger tubes are fixed into position by spacers. In order to inspect a heat exchanger tube, a measurement probe is inserted therein and the tube is exposed section by section to an electromagnetic alternating field having a predeterminable frequency that generates local eddy currents in the tube wall. The local eddy currents induce in an eddy current sensor a voltage signal that varies depending on the state of the material and the thickness of the tube wall. In order to detect the position and the tight fit of a spacer, the voltage signal induced in a tube section by a spacer is stored and the voltage signals stored during inspection of a heat exchanger are evaluated by comparison with a reference signal.