Plate heat exchanger

Abstract

Heat transfer plates are stacked, each being provided with a plurality of passage holes, a flow-path forming gasket is interposed between peripheries of each adjacent ones of the heat transfer plates, thereby alternately forming a first flow path to pass a high-temperature fluid, a second fluid to pass a low-temperature fluid, and communicating paths to cause the fluids to flow in and out of the first flow path and the second flow path on opposite sides of each heat transfer plate, and communicating-path forming gaskets surrounding the passage holes are interposed between adjacent ones of the heat transfer plates, thereby forming a communicating path to cause a fluid to flow in and out of the first flow path and a communicating path to cause a fluid to flow in and out the second flow path. Each communicating-path forming gasket is made up of inner and outer gasket members arranged in two lines, the inner gasket member surrounding the passage holes while the outer gasket member surrounding the inner gasket member.

1 . A plate heat exchanger wherein:
 a plurality of heat transfer plates are stacked, each being provided with a plurality of passage holes;   a flow-path forming gasket is interposed between peripheries of each adjacent ones of the plurality of heat transfer plates, thereby alternately forming a first flow path adapted to pass a high-temperature fluid and a second flow path adapted to pass a low-temperature fluid on opposite sides of each heat transfer plate;   communicating-path forming gaskets surrounding the passage holes are each interposed between each adjacent ones of the plurality of heat transfer plates, thereby forming a communicating path adapted to cause a fluid to flow in and out of the first flow path and a communicating path adapted to cause a fluid to flow in and out the second flow path; and   each of the communicating-path forming gaskets is made up of an inner gasket member and an outer gasket member arranged in two lines, the inner gasket member surrounding the passage holes while the outer gasket member surrounding the inner gasket member.   
     
     
         2 . The plate heat exchanger according to  claim 1 , wherein the communicating-path forming gasket is arranged in two parallel lines only between the heat transfer plates which form the communicating path through which the high-temperature fluid flows.) 
     
     
         3 . A plate heat exchanger wherein:
 a plurality of cassette plates are stacked, each being made up of two heat transfer plates which are provided with a plurality of passage holes and are permanently joined on peripheries;   a flow-path forming gasket is interposed between peripheries of each adjacent ones of the plurality of cassette plates;   communicating-path forming gaskets surrounding the passage holes are each interposed between each adjacent ones of the plurality of heat transfer cassette plates, thereby alternately forming a first flow path adapted to pass a high-temperature fluid and a second flow path adapted to pass a low-temperature fluid inside each cassette plate and between the cassette plates;   wherein each of the communicating-path forming gaskets is made up of an inner gasket member and an outer gasket member arranged in two lines, the inner gasket member surrounding the passage holes while the outer gasket member surrounding the inner gasket member.   
     
     
         4 . The plate heat exchanger according to  claim 1 , wherein a drain hole is formed in the heat transfer plates between the inner gasket member and the outer gasket member of each of the communicating-path forming gaskets. 
     
     
         5 . The plate heat exchanger according to  claim 1 , wherein a gas supply hole is formed in the heat transfer plates between the inner gasket member and the outer gasket member of each of the communicating-path forming gaskets; and an enclosed space surrounded by the inner gasket member, the outer gasket member, and the heat transfer plates is filled with an inert gas.