Patent ID: 6516874
Filing Date: 2003-02-11
Classification: F28D,F28F

Abstract:
A heat exchanger comprising an outer housing and a plate pack assembly located within said housing, said housing including a top cover member and a bottom cover member, a primary inlet header and a primary outlet header each of which is connected to said top cover member and said bottom cover member and are located at opposed ends of said plate pack assembly, a plurality of secondary inlet headers and a plurality secondary outlet headers each of which is arcuate in cross section and extends vertically for connection to said top cover member and said bottom cover member, said secondary inlet headers being located at one side of said plate pack assembly and said secondary outlet headers being located on the opposite side of said plate pack assembly, said plate pack assembly comprising a plurality of generally rectangular cassettes stacked one over the other with a top cassette located adjacent said top cover member and a bottom cassette located adjacent said bottom cover member, each of said cassettes including a first heat transfer plate and a second heat transfer plate, said first and second heat transfer plates each being formed with a pair of laterally spaced side flanges and a pair of opposed end flanges, said end flanges being in a plane offset vertically from the plane of said side flanges, said first and second heat transfer plates being joined together by a continuous weld along said side flanges, said first heat transfer plate and said second heat transfer plate each having a body portion formed with depressions on opposite sides thereof that provide first and second fluid passages for fluid flow between the heat transfer plates of adjacent cassettes, said first fluid passages communicating with said primary inlet header and said primary outlet header and serving as passages for a primary fluid in alternate spaces of said stacked cassettes and said second fluid passages communicating with said secondary inlet header and said secondary outlet header and serving as passages for a secondary fluid in remaining spaces of said stacked cassettes, each of said alternate spaces for said primary fluid being provided by said pair of end flanges formed with each cassette at the opposed ends of said each cassette and each of said remaining spaces being provided by said side flanges of adjacent cassettes, shim means for filling said remaining spaces between the side flanges of the top cassette and the top cover plate and the flanges of the side flanges of the bottom cassette and the bottom cover plate, and baffle means located in said remaining spaces between said top cassette and said bottom cassette for directing said secondary fluid through said second fluid passages, said baffle means being maintained in position within said remaining spaces by vertical support bars secured to said top and bottom cover members along each side of said plate pack assembly.