Method of constructing a plate type heat exchanger

Claim 1

IN THE COMBINATION OF A BRAZED PLATE TYPE HEAT EXCHANGER HAVING FIRST AND SECOND PASSAGEWAYS DISPOSED ON OPPOSITE SIDES OF A COMMON WALL FOR EXCHANGING HEAT THERETHROUGH BETWEEN FIRST AND SECOND HEAT EXCHANGER FLUIDS FLOWING IN SAID FIRST AND SECOND PASSAGEWAYS THERETHROUGH RESPECTIVELY, WHEREIN ONLY THE FIRST OF SAID FIRST AND SECOND PASSAGEWAYS CONTAINS A HEAT TRANSFER PACKING EXTENDING FROM SAID COMMON WALL TO THE OPPOSITE WALL OF SAID FIRST PASSAGEWAY, THE METHOD OF ESTABLISHING A HIGHLY THERMAL CONDUCTING UNION BETWEEN SAID PACKING AND SAID COMMON WALL COMPRISING THE STEPS OF: PROVIDING WITHIN SAID SECOND PASSAGEWAY A SPACER MEMBER EXTENDING FROM SAID COMMON WALL IN SPACING RELATION TO THE OPPOSITE WALL OF SAID SECOND PASSAGEWAY; PROVIDING A BRAZING ALLOY BETWEEN SAID PACKING AND SAID COMMON WALL; HEATING SAID EXCHANGER TO A TEMPERATURE SUFFICIENTLY HIGH TO ALLOW BRAZING ALLOY TO FLOW BETWEEN SAID PACKING AND SAID COMMON WALL; SUPPORTING SAID COMMON WALL INWARDLY OF THE MARGINS THEREOF IN CONTIGUOUS RELATION WITH SAID PACKING DURING THE HEATING STEP VIA FORCES EXERTED BY SAID SPACER MEMBER; COOLING SAID EXCHANGER THEREBY SOLIDIFYING SAID BRAZING ALLOY IN BONDING RELATION WITH SAID COMMON WALL AND SAID PACKING; COLLAPSING SAID SPACER MEMBER AND WITHDRAWING SAID MEMBER FROM SAID SECOND PASSAGEWAY.