Plate-and-shell heat exchangers (PSHE)

Plate-and-shell heat exchangers (PSHE) combine the high thermal efficiency of plate heat exchangers with the mechanical strength and pressure resistance of shell-and-tube heat exchangers. They consist of a fully welded plate pack housed within a cylindrical shell, enabling them to operate under demanding temperature and pressure conditions whilst maintaining excellent heat transfer performance. This hybrid construction makes PSHEs particularly suitable for applications involving aggressive media, high pressures or large temperature differences, such as refrigeration, petrochemical processes, power generation and offshore installations.

The welded plate pack forms narrow flow channels that induce strong turbulence, thereby increasing heat transfer coefficients and minimising fouling. Compared with conventional tube heat exchangers, PSHEs offer a significantly more compact design and require less installation space, whilst delivering comparable or even better thermal performance. Thanks to the fully welded construction, no gaskets are required between the plates, reducing the risk of leakage and making the heat exchanger suitable for media that can corrode elastomeric sealing materials.

The choice of material is of great importance for durability and compatibility with process media. Stainless steel, titanium and high-grade alloys are often used because of their corrosion resistance and ability to withstand thermal stress. Although plate-and-shell heat exchangers offer excellent efficiency and reliability, maintenance can be more complex than with gasketed plate heat exchangers, as the welded plate pack cannot be easily dismantled for mechanical cleaning. Therefore, process media should preferably be relatively clean or suitable for chemical cleaning.

Overall, plate-and-shell heat exchangers offer an advanced and versatile solution for heat transfer, combining compactness, robustness and high thermal efficiency for demanding industrial applications.