How many structural forms of plate heat exchanger gaskets are there? _
868 sealing gasket is an important part of the plate heat exchanger. When assembling, first use the adhesive to stick the gasket in the sealing groove of the plate, and in the circumferential groove of the hole according to the needs of fluid flow To place the gasket of the plate heat exchanger to allow or prevent the fluid from entering the channel between the plates to achieve the purpose of heat exchange. There are many structural forms of gaskets, and their cross-sectional forms are roughly rectangular, trapezoidal, hexagonal, pentagonal and so on. There are two types of commonly used forms: one form, the upper part of the cross-section of the gasket is pointed; the other form, the upper part is flat. The former is to increase the degree of deformation of the sealing gasket through the difference in size from the tip to the middle. Its structural design is actually still a plane seal, but a non-linear seal, because the bottom of the plate sealing groove is flat, when the bottom of the plate sealing groove is flat When there are defects, this structure can offset some. The purpose of the latter design is to reduce the amount of compression of the gasket, and its compression form is flat compression. The main disadvantage is that during the assembly process of the plates, the plates are easily misaligned, the clamping force is too large, and the plates are easily deformed. Through analysis, research and experimentation. Shows the gasket section corresponding to the seal groove, which makes the assembly easier and improves the pressure-bearing capacity of the plate. Generally, the ratio of the compression of the gasket to its original thickness, that is, the compression ratio, is used as the basis for the design of the gasket. Based on years of design experience and analysis of the sealing structure of a large number of plate heat exchangers at home and abroad, the author believes that it is ideal to control the compression ratio between 20% and 25%. The material, structure and compression ratio of the gasket are directly related to the sealing effect of the plate heat exchanger. At present, the commonly used gasket materials include synthetic rubber and asbestos rubber. The commonly used synthetic rubbers are nitrile rubber, EPDM rubber and fluorine rubber. The physical performance indicators of synthetic rubber gaskets mainly include permanent compression deformation and elongation at break under working conditions. The hardness indicators of rubber gaskets should be determined according to the form of the sealing groove and the amount of compression. The plates are mixed and assembled, which can make the application fields of plate heat exchangers more extensive nowadays. It not only greatly enhances the adaptability of the plate heat exchanger, but also has a higher heat transfer coefficient and a smaller flow resistance, so it has good economic benefits in terms of high efficiency and energy saving. At the same time, according to the rigidity of the plate, the rational design of the sealing groove and the sealing gasket can effectively improve the stability of the sealing gasket in the sealing groove and the reliability of the sealing, which is an important condition to ensure the sealing effect. The follow-up investigation and feedback information on the user's usage proves that the sealing groove form and the sealing gasket are more suitable design schemes, and their pressure-bearing capacity and service life are greatly improved compared with the previously designed products.