A heat exchanger is a device that transfers part of the heat of a hot fluid to a cold fluid, also known as a heat exchanger. Heat exchangers have a place in chemical, petroleum, power, food, and many other industrial productions. Heat exchangers in chemical production can be used as heaters, coolers, condensers, evaporators, reboilers, and so on. For example, the Teflon heat exchanger used in power plants is a new type of equipment for heat recovery of power plants to reduce the exhaust temperature. The use of a fluoroplastic heat exchanger prevents acid corrosion and reduces the flue gas temperature to less than 100 degrees. Zhengzhou University of Technology has successfully developed the technology of limited expansion and pressure heating welding for PTFE (F-4) tube sheet, and solved the key technology for connection between fluorine plastic tube and tube sheet. Subsequently, domestically produced various types of heat exchangers were gradually put into practical production applications and achieved good results.