Method of manufacturing a block-type heat exchange element

A method of manufacturing a block-type heat exchange element including a block having mutually opposed first and second surfaces and mutually opposed third and fourth surfaces intersecting said first and second surfaces, said block having a series of discrete first fluid channels extending therethrough between said first and second surfaces and a series of discrete second fluid channels extending therethrough between said third and fourth surfaces independently from said first fluid channels, said method comprising the steps of:

• (a) preparing a molding material in an extrusion moldable state;
• (b) extruding said molding material to form a continuous molding having a predetermined transversal cross-sectional configuration and having mutually opposed, continuous first and second surfaces forming said first and second surfaces of the block and extending in parallel to the direction of extrusion, said continuous molding having a series of discrete first passages extending therethrough in parallel to the direction of extrusion and each having an elongated cross-sectional configuration extending toward said continuous first and second surfaces up to a predetermined first depth therefrom, said continuous molding further having a series of discrete second passages extending there through in parallel to the direction of extrusion and each having an elongated cross-sectional configuration extending toward said continuous first and second surfaces up to a predetermined second depth therefrom, said second depth being greater than said first depth, said second passages being arranged alternately with said first passages and separated from said first passages by partition walls extending toward said continuous first and second surfaces and extending in the direction of extrusion, said second passages forming said second fluid channels in said block;
• (c) setting said continuous molding;
• (d) cutting said continuous molding in the transverse direction at a predetermined length to form a molding section having end surfaces forming said third and fourth surfaces of the block, said first and second passages being opened by said cutting into said third and fourth surfaces;
• (e) closing openings of said first passages opened into said third and fourth surfaces by a closure material;
• and
• (f) cutting out at least parts of said molding section along said first and second surfaces at a predetermined third depth intermediate to said first and second depth until said first passages are opened into said first and second surfaces to form said first fluid channels.