internal passageway application_number US 77804077 A description referring to the drawings fig1 schematically depicts the formation of the bonded assembly of the present invention in accordance with fig1 a first sheet of metal 10 and a second sheet of metal 11 are provided at least one metal tube 12 is placed between the first and second sheets corresponding to a predetermined configuration of fluid passageways to form an assembly 14 the tube 12 has a weld inhibiting material 13 therein substantially throughout the extent thereof the assembly 14 is pressure welded as by feeding the assembly through rolls 15 and 16 to reduce the thickness thereof and to form a bonded assembly or pressure welded article 17 wherein the components thereof are pressure welded in the areas thereof not separated by weld inhibiting material naturally if desired a plurality of sheets 10 and or 11 may be employed based on the characteristics desired in the final product wherein the sheets may be of similar or dissimilar compatible metals in the preferred embodiment indefinite length strip is utilized which is subsequently sheared to desired length naturally the process may be conducted as a batch type procedure where sheets are used generally corresponding to final panel length fig1 schematically shows the formation of the bonded panel by feeding the components thereof simultaneously between rolls 15 and 16 as is apparent the present invention contemplates such simultaneous feeding of components or other variants thereof that will be obvious to one skilled in the art thus tube 12 may be preliminarily spot welded to the surface of the first sheet.