The baffles in the heat exchanger can change the flow direction of the fluid in the shell, increase the flow velocity of the fluid in the shell, increase the turbulence of the medium, improve the heat transfer efficiency and support the tube bundle.
When the total number of tubes of the heat exchanger is the same, increasing the number of tubes can increase the flow rate in each tube, thereby increasing the heat transfer coefficient and reducing the required heat transfer area. At the same time, however, the pressure drop is increased, and the fluid cannot be completely exchanged in a countercurrent manner, and the heat exchanger structure is more complicated. Therefore, the number of tubes generally used is not less than 2 and not more than 8, and should be selected according to actual process requirements.
What are the causes of leakage in the tubular heat exchanger?
The internal leakage of the heat exchanger may have the following reasons:
1. The heat exchange tube is corroded and perforated, or broken
2. Corrosion of the nozzle is caused by leakage
3. The expansion joint between the heat exchange tube and the tube sheet is loose
4. Cracks occur in the welded joint between the heat exchange tube and the tube sheet, and the pores or corrosion perforations
5. Small floating head bolts loose or broken
6. Small floating head gasket is damaged
7. Small floating head or floating tube plate seal is damaged