Abstract: The detection method of the tube bundle of the heat exchanger is discussed. The detection principle of the double pulse detection technique is introduced. The comparative advantage of the double pulse detection technology is presented. Comprehensively inspect and analyze all defects in the heat exchanger tube bundles using dual pulse reflectometry ultrasonic pulse reflectometry and acoustic pulse reflectometry. By analyzing the data and results, this technique could calculate the type, size and location of the defects, and then evaluate the overall performance of the heat exchanger tube bundle.