Plate heat exchanger

Abstract

A plate heat exchanger comprises first and second frame plates, side walls, and a stack of heat transfer plates. The heat transfer plates each has a center portion and a peripheral portion encircling the center portion, and they are arranged in pairs between the first and second frame plates. A first flow path for a first fluid exists between the heat transfer plates of the pairs and a second flow path for a second fluid exists between the pairs of heat transfer plates. The side walls extend between the first and second frame plates and enclose the stack of heat transfer plates. A first side wall of the side walls includes a through hole for draining a substance, originating from one of the first/second fluids, from inside to outside of the heat exchanger A first portion of the inside surface of the first side wall slopes towards the hole.

1 . A plate heat exchanger comprising a first frame plate, a second frame plate, a first number of side walls and a stack of heat transfer plates each having a center portion and a peripheral portion encircling the center portion, the heat transfer plates being arranged in pairs between the first and second frame plates and essentially parallel thereto, a first flow path for a first fluid being formed between the heat transfer plates of the pairs and a second flow path for a second fluid being formed between the pairs of heat transfer plates, the side walls extending between the first and second frame plates and enclosing the stack of heat transfer plates, a first side wall of the side walls, having an inside surface facing the stack of heat transfer plates, being provided with a through hole for draining of a substance from an inside to an outside of the plate heat exchanger, said substance originating from one of the first and second fluids, wherein at least a first portion of the inside surface of the first side wall is sloping towards the hole for facilitating the draining of the substance. 
     
     
         2 . A plate heat exchanger according to  claim 1 , wherein the first side wall comprises an inner portion and an outer portion, which are separately formed, the inner portion comprising an inner surface and an outer surface, which inner surface is comprised in the inside surface of the first side wall, and the outer portion comprising an inner surface arranged to engage with the outer surface of the inner portion. 
     
     
         3 . A plate heat exchanger according to  claim 2 , wherein the inner portion and the outer portion of the first side wall are made of different materials. 
     
     
         4 . A plate heat exchanger according to  claim 2 , wherein the outer portion of the first side wall comprises a recess arranged to receive the inner portion of the first side wall. 
     
     
         5 . A plate heat exchanger according to  claim 2 , wherein the inner surface of the outer portion and the outer surface of the inner portion of the first side wall are essentially plane. 
     
     
         6 . A plate heat exchanger according to  claim 1 , wherein the inside surface of the first side wall comprises a second number of inclined planes sloping towards the hole and adjoining each other along essentially straight lines extending from the hole. 
     
     
         7 . A plate heat exchanger according to  claim 1 , adapted for use as a condenser, wherein said one of the first and second fluids contains matter condensable into the substance and the other one is a cooling agent and the flow path of said one of the first and second fluids is in flow communication with the hole of the first side wall. 
     
     
         8 . A plate heat exchanger according to  claim 1 , wherein the heat transfer plates of each pair are permanently joined to each other by two opposing edge plate joints between the peripheral portions of the heat transfer plates of the pair. 
     
     
         9 . A plate heat exchanger according to  claim 1 , wherein each two of the pairs of heat transfer plates are permanently joined to each other by two opposing edge pair joints between the peripheral portions of the two adjacent heat transfer plates of the different pairs. 
     
     
         10 . A plate heat exchanger according to  claim 8 , wherein the joints are made by welding. 
     
     
         11 . A plate heat exchanger according to  claim 1 , wherein the first flow path and the second flow path are essentially transverse in relation to each other.