Semi-welded Heat Exchangers of TGT Co., Known for the TAHA-SW series, includes pairs of grooved plates which are welded on one side and sealed on the other side by gasket. Exactly similar to the plate heat exchangers, the pair of plates, or the so-called cassette, are compressed by rigid frame and bolts. This type of design is very suitable for corrosive fluid flow into the welded channel and in contact with ring gaskets on the port side of the not welded plates. The advantages of this type of heat exchanger in compare with fully welded exchanger are, easy to disassemble and ability to increase its capacity. The operating temperature range of this type of exchanger is -47 to 170 ° C, and depending on their size, the pressure range is up to 40 bar. The special design of this type of heat exchanger is very suitable for water vapor condensation and evaporation. Semi-welded plate heat exchangers are also available for refrigeration cycles. This type of heat exchanger has the ability to handle most of the refrigerants on the weld surface, and is especially recommended for ammonia applications.