What are the main applications of expansion joints? What are the main principles of the application?
The medium around the expansion joint does not produce electric current, the medium acts directly with the expansion joint chemically and corrodes the expansion joint. The expansion joints are in contact with each other, the expansion joints are in contact with the closing body and the expansion joints as well as the difference in concentration of the medium, the difference in oxygen concentration, etc., which will produce a potential difference and electrochemical corrosion will occur, resulting in corrosion of the expansion joints on the Yang side. The expansion joint medium at a certain speed, the floating fines in the medium ramming the expansion joint, causing local damage to it.
The application of expansion joint in valve pipeline. High-speed liquid moving medium directly rushes the expansion joint to cause local damage; when the medium of expansion joint is mixed with injection and local vaporization, bubbles are generated to impact the surface of the expansion joint, causing local damage. The situation of the medium coupled with the alternating effect of chemical corrosion will strongly leach the expansion joint. The expansion joint will produce damage such as abrasion, bruising and squeezing during the opening and closing process. Between the two expansion joints, atoms occur with each other under the action of high temperature and pressure, producing adhesion, when the expansion joints move with each other. The adhesion is easy to pull tear.
The application of expansion joints in sewage pipes. The higher the surface roughness of the expansion joint, the more likely this phenomenon occurs. In the process of closing the expansion joint, the expansion joint will touch and squeeze the expansion joint in the process of returning to the seat, so that the sealing surface will be locally worn or indentation will be produced. Expansion joint plays the role of variable resistance in the pipeline. It changes the turbulence of the process fluid or, in the case of laminar flow, provides a pressure drop that is caused by changing the resistance or "friction" of the expansion joint. This pressure reduction process is often referred to as "throttling".
Application of expansion joints in gas/liquid pipelines. In the case of gases, it is close to the isothermal adiabatic state and the deviation depends on the non-ideal degree of the gas. In the case of liquids, the pressure is consumed by turbulent flow or viscous friction, both of which convert the pressure into a slight increase in temperature. In this case, it is determined that the expansion joint required is supplied by compressed air, which should be dried in an outdoor facility to prevent freezing, and should be purified and filtered.
