Preparation of sheet stock having longitudinal internal weakening therein

Claim 1

THE METHOD OF PREPARING LAMINATE METAL STRIP MATERIAL OF PREDETERMINED WIDTH FOR EXPANSION INTO TUBULAR FORM, WHICH COMPRISES PREPARING A METAL BILLET HAVING OPPOSITE SURFACES TO BE ENGAGED BY THE ROLLS DURING ROLLING, SAID BILLET HAVING A LONGITUDINALLY EXTENDING INTERNAL CHANNEL AND A PAIR OF LONGITUDINALLY EXTENDING INTERNAL DISCONTINUITIES, THE DISCONTINUITIES EACH HAVING A GREATER DIMENSION IN THE DIRECTION BETWEEN SAID ROLL-ENGAGING SURFACES THAN THE LIKE DIMENSION OF THE CHANNEL, SAID CHANNEL BEING SPACED TRANSVERSELY FROM EACH OF THE DISCONTINUITIES BY AN INTERGRAL METAL PORTION OF THE BILLET, LONGITUDINALLY ROLLING THE BILLET WITH WELD-PREVENTING MATERIAL IN SAID CHANNEL AND DISCONTINUITIES TO CAUSE REDUCTION OF THE BILLET TO THE THICKNESS DESIRED FOR THE STRIP MATERIAL AND THEREBY PRODUCING A SMOOTH SURFACED STRIP IN WHICH THE DIMENSIONS OF THE INTERNAL WELD-PREVENTING MATERIAL IN THE DIRECTION BETWEEN THE ROLL ENGAGED SURFACES OF THE BILLET HAVE BEEN COORDINATELY REDUCED WITH THE SAID DIMENSIONS OF THE RESIDUES OF THE DISCONTINUITIES BEING GREATER THAN THE SAID DIMENSION OF THE RESIDUE OF THE CHANNEL, AND THEN APPLYING FORCES TO THE ROLLED PRODUCT WHEREBY TO OVERSTRESS IT AT AND EFFECT LONGITUDINAL SEPARATION OF THE METAL BETWEEN THE ROLLED SURFACES OF THE STRIP AND THE RESIDUES OF THE DISCONTINUITIES AND THEREWITH FROM A NARROWER STRIP OF MATERIAL HAVING A WIDTH ESSENTIALLY EQUAL TO THE TRANSVERSE DISTANCE BETWEEN THE ROLLED RESIDUES OF THE DICONTINUITIES, THE SEPARATED STRIP HAVING METAL LAMINATIONS AT ITS ROLLED SURFACES, SAID LAMINATIONS BEING SEPARATED BY THE ROLLED RESIDUE OF THE CHANNEL AND BEING INTEGRALLY CONNECTED AT THE EDGES BY THE ROLLED RESIDUES OF THE BILLET METAL ORIGINALLY PRESENT BETWEEN THE SAID CHANNEL AND THE RESPECTIVE DISCONTINNUITIES.

Claim 2

THE METHOD OF PREPARING LAMINATE METAL STRIP MATERIAL OF PREDETERMINED WIDTH FOR EXPANSION INTO TUBULAR FORM, WHICH COMPRISES PREPARING A METAL BILLET HAVING OPPOSITE SURFACES TO BE ENGAGED BY THE ROLLS DURING ROLLING, SAID BILLET HAVING A LONGITUDINALLY EXTENDING INTERNAL CHANNEL AND A PAIR OF LONGITUDINALLY EXTENDING INTERNAL DISCONTINUITIES, THE DISCONTINUITIES EACH HAVING A GREATER DIMENSION IN THE DIRECTION BETWEEN SAID ROLL-ENGAGING SURFACES THAN THE LIKE DIMENSION OF THE CHANNEL, SAID CHANNEL BEING SPACED TRANSVERSELY FROM EACH OF THE DISCONTINUITIES BY AN INTERGRAL METAL PORTION OF THE BILLET, LONGITUDINALLY ROLLING THE BILLET WITH WELD-PREVENTING MATERIAL IN SAID CHANNEL AND DISCONTINUITIES TO CAUSE REDUCTION OF THE BILLET TO THE THICKNESS DESIRED FOR THE STRIP MATERIAL AND THEREBY PRODUCING A SMOOTH SURFACED STRIP IN WHICH THE DIMENSIONS OF THE INTERNAL WELD-PREVENTING MATERIAL IN THE DIRECTION BETWEEN THE ROLL ENGAGED SURFACES OF THE BILLET HAVE BEEN COORDINATELY REDUCED WITH THE SAID DIMENSIONS OF THE RESIDUES OF THE DISCONTINUITIES BEING GREATER THAN THE SAID DIMENSION OF THE RESIDUE OF THE CHANNEL, AND THEN APPLYING FORCES TO THE ROLLED PRODUCT WHEREBY TO OVERSTRESS IT AT AND EFFECT LONGITUDINAL SEPARATION OF THE METAL BETWEEN THE ROLLED SURFACES OF THE STRIP AND THE RESIDUES OF THE DISCONTINUITIES AND THEREWITH FROM A NARROWER STRIP OF MATERIAL HAVING A WIDTH ESSENTIALLY EQUAL TO THE TRANSVERSE DISTANCE BETWEEN THE ROLLED RESIDUES OF THE DICONTINUITIES, THE SEPARATED STRIP HAVING METAL LAMINATIONS AT ITS ROLLED SURFACES, SAID LAMINATIONS BEING SEPARATED BY THE ROLLED RESIDUE OF THE CHANNEL AND BEING INTEGRALLY CONNECTED AT THE EDGES BY THE ROLLED RESIDUES OF THE BILLET METAL ORIGINALLY PRESENT BETWEEN THE SAID CHANNEL AND THE RESPECTIVE DISCONTINNUITIES.