Shell & tube heat exchanger - Construction & working

Shell and tube

1. Shell & tube Heat exchanger

2. Shell and tube heat exchanger consists of a bundle of round tubes placed inside the cylindrical shell. The tube axis parallels to that of the shell. One fluid travels from inside the tubes while the other over the tubes.

3. Components Shell Tube bundle Front and rear headers of shell baffles

4. A shell and tube heat exchanger consists of a series of tubes housed within a cylindrical container known as a ‘shell’ Each tube passes through a series of baffles and tube sheets One of the tube sheets is fixed and one is free to move , this allows for thermal expansion as the heat exchanger is heated. The flowing medium within the tubes is known as the ‘tube side’ medium. The flowing medium outside of the tubes is known as the ‘shell side’ medium.

5. Advantages Cheap compared to plate heat exchangers. Relatively simple design and easy to maintain. Suitable for higher pressures and temperatures compared to plate heat exchangers. Easy to find and isolate leaking tubes. Tubes can be 'double walled' to reduce the likelihood of the shell side fluid leaking into the tube side fluid (or vice versa). Do not foul as easily as plate heat exchangers.

6. Disadvantages Less efficient than plate heat exchangers. Require more space to open and remove tubes. Cooling capacity can not be increased, but a plate heat exchanger's can be.