The material of heat transfer elements of snake tube heat exchanger can be divided into metal and non-metal. In recent years, serpentine tube metal heat exchanger has developed rapidly in the world, and has become the main form of heat exchange equipment. Non metallic serpentine tube heat exchanger has high cleanliness, heat exchange material, corrosion resistance than a variety of alloys, such as Zhengzhou University of technology non-metallic serpentine polytetrafluoroethylene heat exchanger manufacturing process research, promote the application of serpentine tube heat exchanger in petrochemical industry, sulfuric acid, medicine, electroplating, electroplating Light industry and other fields have gradually been widely used. 1. Picture structure of immersed snake tube heat exchanger: this kind of heat exchanger is mostly made of metal tubes, or made into various conditions suitable for the container, and immersed in the liquid in the container. Immersed serpentine tube heat exchanger is one of the inter wall heat exchangers, which uses serpentine tube as heat transfer element. This is an old heat exchanger. It is simple in structure, convenient in manufacture, installation, cleaning and maintenance, low in price, and especially suitable for cooling and condensing high-pressure fluid, so it is still widely used in modern times. But the snake tube heat exchanger is bulky and bulky; The metal consumption per unit heat transfer area is large and the heat transfer efficiency is low. The utility model has the advantages of simple structure, convenient anticorrosion, and can withstand high pressure. However, because the volume of the vessel is much larger than that of the tube, the surface heat transfer coefficient of the fluid outside the tube is smaller. In order to improve the heat transfer coefficient, the agitator can be installed in the vessel.