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The bellows heat exchanger is based on the traditional tube-and-tube heat exchanger, applying the theory of enhanced heat transfer and the unique design of the peaks and troughs of the heat exchange tube, which makes a major breakthrough in the performance of the heat exchanger.

The corrugated tube is a double-sided enhanced heat transfer tube that is processed by a special process on the basis of an ordinary heat exchange tube and has concave and convex waves inside and outside the tube, which can strengthen the inside and outside of the tube. From the waveform, it is divided into two categories: spiral corrugation and annular corrugation. Because the joints of spiral corrugated pipes are difficult to handle and their use is limited, ring corrugated pipes are now widely used. Ring bellows are divided into trough-shaped bellows, trapezoidal bellows, zoom tubes, and corrugated tubes.