Semi Welded Phe is used for all types of refrigerants, or in other processes where gaskets are not suitable for one of the media. The refrigerant flows in laser-welded, sealed plate channels, and the brine in gasketed channels. The flexible modular design copes with fatigue stresses and ice formation. The semi-welded heat exchanger handles most refrigerants on the welded side and is particularly suitable for ammonia duties. Standard plate materials are stainless steel and titanium. Temperature range is -47°C to 150°C; pressure is up to 63 bar, depending on size.

Heat transfer technology involves bringing two substances at different temperatures close to each other so that one either heats or cools the other.
The semi-welded gasketed plate-and-frame heat exchanger consists of a series of thin corrugated twin plates. One side is welded and the other side is fitted with gaskets. The plates are then compressed together in a rigid frame to create an arrangement of parallel flow channels.
The two fluids flow in alternate channels so there is a large surface area over which the transfer of heat energy from one fluid to the other can take place. The channels are specially designed to induce maximum turbulence in both fluid flows in order to make heat transfer as efficient as possible.
The design also makes it easy to separate the plates quickly - when, for example, they need to be cleaned. It also makes it easy to adjust capacity by simply adding or removing plates when required.