The structure of the carbon steel tube heat exchanger is relatively simple, compact and cheap, but the outside of the tube cannot be cleaned mechanically. The tube bundles of this type of heat exchanger are connected to the tube sheets, which are welded to both ends of the shell and connected to a top cover. The top cover and the shell are equipped with fluid inlet and outlet pipes.
A series of baffles are usually installed outside the tubes perpendicular to the tube bundle. At the same time, the connection between the tube and the tube sheet and the shell are rigid, and there are two fluids with different temperatures inside and outside the tube. Therefore, when the temperature difference between the tube wall and the shell wall is large, due to the different thermal expansion of the two, a large temperature difference stress is generated, which may cause the tube to twist or loosen from the tube plate, or even damage the heat exchanger.
In order to overcome the temperature difference stress, a temperature difference compensation device is required. Generally, when the temperature difference between the tube wall and the shell wall50℃In the above case, for safety reasons,Carbon steel tube heat exchangerThere should be a temperature difference compensation device. But the compensation device(expansion joint)It can only be used when the temperature difference between the shell wall and the tube wall is less than60~70℃and the shell-side fluid pressure is not high, generally the shell-side pressure is higher than0.6MpaWhen the compensation ring is too thick, it is difficult to expand and contract, and the temperature difference compensation function is lost, so other structures should be considered.
The vortex hot film of the carbon steel tube heat exchanger mainly adopts the new vortex hot film heat transfer technology, which increases the heat transfer effect by changing the fluid motion state. When the medium passes through the vortex tube surface, it washes the tube surface, thereby improving the heat transfer efficiency. At the same time, this structure achieves corrosion resistance, high temperature resistance, high pressure resistance, and anti-fouling functions. The fluid channels of other types of heat exchangers are in the form of fixed direction flow, forming flow around the surface of the heat exchange tube, and the convection heat transfer coefficient is reduced.