A device that transfers heat through a conducting wall from one fluid to another. Heat exchangers are used to transfer heat from a hotter fluid (liquid or gas) to a colder fluid. This broad definition covers a wide range of equipment, including boilers, condensers, distilling plants, and ventilation cooling coils.
- Plate heat exchanger – It consists of five basic elements: the cover, the carrier rail, the heat transfer plates, the support column, and the tie bolts. The inlet and outlet for both fluids are usually located in the same cover. The fluids are separated by the heat transfer plates. Each plate contains a gasket that fits into grooves pressed in the plate and in the nozzle ports. The gasket prevents the two fluids from mixing. The gasket is vented to the atmosphere, which permits a leak to be promptly detected. The plates are sandwiched between a fixed cover and a movable cover by tie bolts. The top and bottom carrier rails align the plates to each other.
- Shell-and-tube heat exchanger – Shell-and-tube heat exchanger is fabricated from round tubes that are settled in, and run parallel to a shell. Heat is transferred between the fluids by passing through the walls of tubes. This type of exchanger consists of six basic elements: the bonnet, tubsheet, shell, tubes, baffles or support plates, and the tie rods.