Heat exchanger

A heat exchanger for first and second fluids, comprising:

• a plurality of substantially identical heat transmission plates and disposed one upon another, each heat transmission plate including a flat section through which heat exchange is made between the first and second fluids, a plurality of annular flanges extending from said flat section, each annular flange defining a through-hole opened through said flat section, and means defining a plurality of openings opened through said flat section, an axis of at least one of said through-holes and an axis of at least one of said openings lying on a first circle on said flat section of said heat transmission plate, said at least one through-hole and said at least one opening being located along said first circle, the axes of adjacent said through-hole and said opening being peripherally separate from each other by a predetermined peripheral distance on said first circle , said plurality of heat transmission plates including first and second heat transmission plates which are located adjacent to and contacted with each other;
• said heat transmission plates being located relative to one another such that said first heat transmission plate is peripherally shifted by said predetermined peripheral distance along said first circle relative to said second heat transmission plate, in which each annular flange of said first heat transmission plate contacts with said flat section of said section heat transmission plate so that said through-hole of said first heat transmission plate is aligned with said opening of said second heat transmission plate;
• and
• means for sealingly connecting said heat transmission plates to each other so that said first and second heat transmission plates are united to define a first fluid flowing space for the first fluid and a second fluid flowing space for the second fluid on opposite sides of said flat section of each of said first and second heat transmission plates.