Convergent-divergent tube belongs to the range of enhanced heat transfer tube. Compare with smooth tube, convergent-divergent tube has the equidistant bamboo-like structure, also known as bamboo-like tube. It can do the heat transferring on both inner and outer wall tubes. Under certain flow velocity, the film heat-transfer coefficient is 70%~100% higher than the smooth tube and with excellent self-preventing fouling property. Convergent-divergent tube can be used to transfer gases and liquids. The heat exchanger device which make of convergent-divergent tube is used extensively in chemical engineering, petrochemical, metallurgical industry and power industry etc. It has advantages as save energy, reduce consumption and environmental protecting. By use of convergent-divergent tube, the heat exchanger device can save over 30% power, reduce 30% raw material and the consumption of operating system also reduced correspondingly.