Method of manufacturing finned structure

Claim 1

THE METHOD OF MAKING A FINNED HEAT EXCHANGER PLATE COMPRISING SUPERPOSING A PAIR OF INSIDE COMPONENT SHEETS WITH WELDABLE SURFACES IN JUXTAPOSITION WITH AN INTERVENING FIRST PATTERN OF WELD PREVENTING MATERIAL APPLIED TO ONE OF SAID COMPONENT SHEETS, SAID PATTERN INCLUDING STRIPES SPACED FROM EACH OTHER AND FROM THE LATERAL EDGES OF SAID SHEETS, APPLYING A PLURALITY OF EDGE-TO-EDGE CONTIGUOUS OUTSIDE COMPONENT SHEETS TO THE OUTSIDE SURFACE OF AT LEAST ONE OF SAID PAIR OF INSIDE SHEETS WITH A SECOND PATTERN OF WELD PREVENTING MATERIAL CONSISTING OF SPACED BANDS EACH EXTENDING FROM ONE EDGE TO AN OPPOSITE EDGE INTERVENING BETWEEN SAID OUTSIDE SURFACE AND THE APPLIED OUTSIDE SHEET ALONG AND ADJACENT SAID CONTIGUOUS EDGES WHICH FORM LINES OF SUBDIVISION OF SAID OUTSIDE COMPONENT SHEET, UNIFYING ADJACENT COMPONENT SHEETS TOGETHER EXCEPT AT THE AREAS OCCUPIED BY SAID PATTERN OF WELD PREVENTING MATERIAL TO FORM A TUBE SHEET HAVING EXPOSED ALONG ITS PERIPHERAL EDGES THE ENDS OF SAID BANDS OF SAID SECOND PATTERNS, BENDING THOSE PORTIONS OF SAID OUTSIDE COMPONENT SHEETS ADJACENT EACH OF SAID LINES OF SUBDIVISION OUTWARDLY TO FORM INTEGRAL FINS AND THEN APPLYING FLUID INFLATION PRESSURE ALONG SAID FIRST PATTERN OF WELD PREVENTING MATERIAL SO AS TO ERECT HEAT EXCHANGER FLUID PASSAGEWAYS IN SAID PLATE STRUCTURE EXTENDING FROM ADJACENT ONE END OF THE TUBE SHEET TO THE OTHER END OF THE TUBE SHEET.

Claim 2

THE METHOD OF MAKING A FINNED HEAT EXCHANGER PLATE COMPRISING SUPERPOSING A PAIR OF INSIDE COMPONENT SHEETS WITH WELDABLE SURFACES IN JUXTAPOSITION WITH AN INTERVENING FIRST PATTERN OF WELD PREVENTING MATERIAL APPLIED TO ONE OF SAID COMPONENT SHEETS, SAID PATTERN INCLUDING STRIPES SPACED FROM EACH OTHER AND FROM THE LATERAL EDGES OF SAID SHEETS, APPLYING A PLURALITY OF EDGE-TO-EDGE CONTIGUOUS OUTSIDE COMPONENT SHEETS TO THE OUTSIDE SURFACE OF AT LEAST ONE OF SAID PAIR OF INSIDE SHEETS WITH A SECOND PATTERN OF WELD PREVENTING MATERIAL CONSISTING OF SPACED BANDS EACH EXTENDING FROM ONE EDGE TO AN OPPOSITE EDGE INTERVENING BETWEEN SAID OUTSIDE SURFACE AND THE APPLIED OUTSIDE SHEET ALONG AND ADJACENT SAID CONTIGUOUS EDGES WHICH FORM LINES OF SUBDIVISION OF SAID OUTSIDE COMPONENT SHEET, UNIFYING ADJACENT COMPONENT SHEETS TOGETHER EXCEPT AT THE AREAS OCCUPIED BY SAID PATTERN OF WELD PREVENTING MATERIAL TO FORM A TUBE SHEET HAVING EXPOSED ALONG ITS PERIPHERAL EDGES THE ENDS OF SAID BANDS OF SAID SECOND PATTERNS, BENDING THOSE PORTIONS OF SAID OUTSIDE COMPONENT SHEETS ADJACENT EACH OF SAID LINES OF SUBDIVISION OUTWARDLY TO FORM INTEGRAL FINS AND THEN APPLYING FLUID INFLATION PRESSURE ALONG SAID FIRST PATTERN OF WELD PREVENTING MATERIAL SO AS TO ERECT HEAT EXCHANGER FLUID PASSAGEWAYS IN SAID PLATE STRUCTURE EXTENDING FROM ADJACENT ONE END OF THE TUBE SHEET TO THE OTHER END OF THE TUBE SHEET.