The heat exchanger is a traditional, widely used heat exchange device. Due to its sturdy construction and the ability to be manufactured from a variety of materials, it is highly adaptable. Heat exchangers are widely used in various industries. They are often used as oil coolers for equipment oil stations in cement production enterprises, and are used as vehicle engine oil coolers. For a long time, steel heat exchangers have always dominated the production and use of heat exchangers due to their strong structure, high reliability, adaptability and wide selection of materials. With the development of technologies such as heat transfer enhancement, heat exchangers are also constantly improving in manufacturing technology and heat transfer performance. However, due to the complexity of the structure and the variety of operating conditions, local failure or even total scrap of the heat exchanger often occurs.
The main components of the heat exchanger include: cylinder, head, tube bundle, tube sheet, baffle, nozzle, flange, etc. Under various working conditions and medium environments, various forms of failure may occur. From the structural analysis, the part that is prone to failure is the joint between the components, such as the joint between the pipe and the tube sheet; from the perspective of the force analysis, the surface of the structure is discontinuous, especially at the sudden change of stress, due to the existence of additional stress. And cause failure, such as the weld of the cylinder and the tube sheet; from the use condition analysis, the thermal stress or the additional stress caused by the high temperature and high pressure, the working medium is corrosive, and the fluid is frequently started and stopped to cause the fluid induction of the heat exchange tube. Vibration, etc., will cause the cylinder, heat exchange tube and even the whole machine to fail.
The main preventive measures for heat exchanger failure are: reducing the gap, selecting the corrosion resistant material, improving the quality of the weld, cleaning regularly, adding corrosion inhibitor to the fluid, controlling the temperature fluctuation of the system, and reducing the flange connection.