Patent ID: 7204300

Claim:
A welded heat exchanger ( 1 ) with plate structure, intended for heat transfer between substances in the same state or in different states, such as a gas or a liquid, comprising a closed stack ( 6 ) of plates consisting of circular heat transfer plates ( 10 ) used as heat transfer surfaces and connected to each other at their outer perimeters ( 13 ) or at the outer perimeters of their flow openings ( 11 , 12 ), one heat transfer medium flowing inside said stack ( 6 ), a housing unit ( 2 ) used as a pressure vessel and consisting of ends ( 4 , 5 ) supporting the stack ( 6 ) of plates and the surrounding housing ( 3 ), another heat transfer medium flowing inside said housing unit ( 2 ), and inlet and outlet passages ( 7 , 8 , 27 , 28 ) for the heat transfer media flowing in the stack ( 6 ) of plates and in the housing unit ( 2 ), extending through the end ( 4 ), characterized in that the inlet and outlet passages ( 26 , 27 ) of the heat transfer medium flowing in the housing unit ( 2 ) are connected to the end plate ( 4 ) of the housing unit ( 2 ), and that the inlet and outlet passages ( 7 , 8 ) of the stack ( 6 ) of plates are connected to the stack ( 6 ) of plates and the end plate ( 4 ), that a flow guide ( 24 ) with the shape of the letter Z or a corresponding shape is fitted between the end plate ( 4 ) of the housing unit ( 2 ) and the stack ( 6 ) of plates, to guide the stream to a flow passage ( 20 ) between the housing ( 3 ) and the stack ( 6 ) of plates and to discharge it from a flow passage ( 21 ), and that the flow passages between the housing ( 3 ) and the stack ( 6 ) of plates consist of thin plates ( 22 , 23 ) curved against the housing ( 3 ) and attached at their sides to side support plates ( 16 , 17 ) of the stack ( 6 ) of plates.