Cold and hot fluids flow and exchange heat in the inner tube and the casing, respectively.
This kind of heat exchanger has several outstanding advantages, so it is still widely used in industrial sectors such as petrochemical industry.
① The structure is simple, and the heat transfer area can be increased or decreased freely. Because it is composed of standard components, no additional processing is required during installation.
② High heat transfer efficiency. It is a pure counter-flow type heat exchanger. At the same time, you can choose a suitable cross-sectional size to increase the fluid speed and increase the heat transfer coefficient of the fluid on both sides, so its heat transfer effect is good. During liquid-liquid heat exchange, the heat transfer coefficient is 870 ~ 1750W / (m2 · ℃). This is particularly suitable for the heat exchange of high pressure, small flow, and low heat transfer coefficient fluids. The shortcomings of the tube-type heat exchanger are the large footprint; the metal consumption per unit heat transfer area is about 5 times that of the shell-and-tube heat exchanger; there are many pipe joints and it is easy to leak;
③ The structure is simple, the working range is large, and the heat transfer area can be easily increased or decreased. The fluid on both sides can increase the flow rate, so that both sides of the heat transfer surface can have a high heat transfer coefficient, which is the metal consumption per unit heat transfer surface. Large, in order to increase the heat transfer area and improve the heat transfer effect, various forms of fins can be installed on the outer wall of the inner tube, and a scraping film disturbance device can be installed in the inner tube to adapt to the heat exchange of high-viscosity fluids.
④ The shape can be arbitrarily changed according to the installation position, which is favorable for installation.
① Maintenance, cleaning and disassembly are troublesome, and leaks are easily caused at detachable connections.
② In production, there are many materials to choose from. Due to the fact that most of the tube-type heat exchangers are not allowed to be welded in the inner tube, welding will cause thermal expansion and cracking, and most of the tube-type heat exchangers are selected to save space. , Bent, the coil is made into the shape of a snake tube, so there are many special corrosion-resistant materials that cannot be produced normally.
③ Sleeve heat exchangers in China have not formed a unified welding standard. Each company chooses a welding method based on the experience of other heat exchange products. Therefore, various problems are common in the welding place of sleeve heat exchangers, which require frequent attention. Inspection and maintenance.