The finned tube heat exchanger is one of the earliest and most successful discoveries in the process of improving tube heat exchange. This method is still the most widely used of all kinds of tube heat transfer surface enhancement heat transfer methods. It is not only suitable for single-fin tube heat exchangers, which are widely used in power, chemical, petrochemical, air-conditioning engineering and refrigeration engineering.
Conventional heat exchanger with smooth tubes can be inspected through the pressure test during the manufacturing process. Finned tubes and finned heat exchangers with inner thread structure have some difficult to pass the water pressure test. The same situation exists in regular inspections. Due to structural reasons, it is difficult to carry out regular surface inspections. For these two situations, two different testing methods are required to ensure quality. This article introduces in detail the methods of inspecting finned tubes and finned heat exchangers. Hierarchical comparison of alternatives in hydrostatic testing project, and the eddy current detection technology of the finned tube under the condition of in-service air cooling. The far-field eddy current method is chosen for inspection. And by comparing the standard sample tube, it is mainly used to adjust the sensitivity of the eddy current detector and ensure the accuracy of the test results. The results show that the eddy current detection technology can be more accurate and reliable. The corrosion of the finned tube under service air cooling is detected, and a reliable basis is provided for judging the use of the finned tube and finned heat exchanger.