Wuxi Suyang Chemical Equipment Co., Ltd

High quality product, professional service, being the core supplier in Chemical Equipment industry!

Home > Knowledge > Content
Main advantages of tubular heat exchangers and differential stress
- Mar 31, 2018 -

The structure of the tubular heat exchanger is relatively simple, compact and inexpensive, but it cannot be mechanically clear outside the tube. Such a heat exchanger tube bundle is connected to the tube sheet, and the tube sheet is welded to both ends of the shell, respectively. Connected to the top cover, the top cover and shell of the tubular heat exchanger are equipped with fluid inlet and outlet connections.

A tubular heat exchanger usually has a series of baffles perpendicular to the tube bundle outside the tube. To a certain extent, the connection between the tube and the tube plate and the shell is rigid, and the tube inside the tube is of two different temperatures. The fluid. Therefore, when the temperature difference between the tube wall and the shell wall is large, due to the difference in thermal expansion between the two, a large temperature differential stress is generated, and the tube twists or loosens the tube from the tube sheet, and even destroys the heat exchanger.

To a certain extent, in order to overcome the temperature difference stress, the tube heat exchanger must have a temperature difference compensation device. In the process of operation, the temperature difference between the tube wall and the shell wall generally exceeds 50° C. For safety reasons, the heat exchanger should be There is a temperature difference compensation device. However, the compensation device (expansion joint) can only be used when the temperature difference between the shell wall and the pipe wall is lower than 60-70°C and the shell-side fluid pressure is not high.

In the floating head type of the tubular heat exchanger, when a tube plate of the heat exchanger is used, the flange is connected with the shell, and the other tube plate is not connected with the shell, so that the tube can be freely heated or cooled. Telescopic, but connect a cap on this tube sheet, which is called "floating head", so this kind of heat exchanger is called floating head heat exchanger.

The tube bundle of the tubular heat exchanger can be pulled out for cleaning; the expansion of the tube bundle does not restrict the shell, so when the temperature difference of the two heat exchanger mediums is large, the thermal expansion amount of the tube bundle and the shell will not be different. Thermal stress is generated.