Views:3 Author:Site Editor Publish Time: 2020-07-09 Origin:Site
Shell and tube heat exchangers are used to repair or replace the deformation of plates. If there is no spare board, the deformed board can be temporarily removed and reassembled. An important part of the device and its function, where the consumable part is the gasket of the plate heat exchanger. Resistant to acid, alkali and salt. Low heat transfer efficiency, small temperature difference, strong anti-fouling and anti-fouling capabilities, high heat transfer coefficient, and can adapt to places with high critical load.
Leaks are prone to occur during operation, and there are many reasons for the leak. According to different reasons, the treatment method for the leakage of the plate heat exchanger is also different. The shell and tube heat exchanger is composed of a shell, a heat transfer tube bundle, a tube sheet, a baffle (baffle) and a tube box. The housing is substantially cylindrical, and the tube bundle is arranged inside, and both ends of the tube bundle are fixed on the tube plate. Two types of hot and cold fluids that exchange heat, one flowing in the tube, is called the tube fluid, and the other is flowing outside the tube, called the shell-side fluid.
In order to increase the heat transfer coefficient of the fluid outside the tube, multiple baffles are usually installed in the housing. The baffle increases the velocity of the fluid on the shell side, forcing the fluid to cross the tube bundle multiple times in a prescribed path, thereby increasing the turbulence of the fluid. The heat exchange tubes may be arranged on the tube sheet in an equilateral triangle or square. The equilateral triangles are compactly arranged, the fluid outside the tube is highly turbulent, and the heat transfer coefficient is large. The square arrangement facilitates cleaning outside the tube and is suitable for fluids that are prone to fouling.
In order to increase the fluid velocity in the tubes, spacers may be arranged at both ends of the tube box to divide the tubes into groups. In this way, the fluid can only pass through a part of the tube at a time, so it travels back and forth multiple times in the tube bundle, which is called a multi-tube. Similarly, in order to increase the flow velocity outside the pipe, a vertical baffle can also be installed in the casing to force the fluid to pass through the casing space multiple times, which is called a multi-casing process. Multiple tubes and multiple shells can be used together.