Corrugated sheet-like yieldable wall element and vessels or tanks made thereof

Claim 1

A SHEET-LIKE METAL PLATE ELEMENT HAVING A FRONT SIDE AND A BACK SIDE AND AT LEAST A PORTION OF WHICH IS FORMED WITH A PLURALITY OF SETS OF AT LEAST ONE INTEGRAL CHANNEL-LIKE CORRUGATION, THE CORRUGATIONS OF EACH SET EXTENDING IN SUBSTANTIALLY PARALLEL SPACED RELATIONSHIP AND INTERSECTING THE CORRUGATIONS OF ANY OTHER SET, EACH INTERSECTION OF CORRUGATIONS COMPRISING ONE CORRUGATION OF EACH SET EXTENDING THERETHROUGH, THE CORRUGATIONS OF ANY ONE SET BEING SUBSTANTIALLY CONGRUENT AND OF UNIFORM CROSS-SECTION THROUGHOUT THEIR LENGTHS EXCEPT IN THE INTERSECTING REGIONS AND HAVING THEIR RAISED CONVEX WAVELIKE PORTIONS PROJECTING ALL FROM A SAME SIDE OF SAID PLATE ELEMENT, EACH CORRUGATION BEING SUBSTANTIALLY SYMMETRICAL ABOUT A PLANE EXTENDING LENGTHWISE OF SAID CORRUGATION AND SUBSTANTIALLY NORMAL TO THE INITIAL SHEET SURFACE OF SAID PLATE ELEMENT, WHEREBY SAID CORRUGATIONS DEFINE THEREBETWEEN SUBSTANTIALLY SMOOTH UNCORRUGATED POLYGONAL AREAS LOCATED IN SAID INITIAL SHEET SURFACE; SAID CORRUGATED PLATE ELEMENT FORMING A SUBSTANTIALLY WHOLLY DEVELOPABLE GEOMETRICAL SURFACE THE FEATURES OF WHICH ARE MADE BY FOLDING, EACH INTERSECTING REGION PROJECTING FROM SAID FRONT SIDE AND EACH ONE OF AT LEAST SOME OF SAID INTERSECTING REGIONS BEING FORMED WITH AT LEAST ONE HOLLOW-LIKE DEPRESSION IN THE SHAPE OF A SUBSTANTIALLY CYLINDRICAL RECESS IMPRESSED INTO AND EXTENDING TRANSVERSELY OF AT LEAST THE CREST PORTION OF AT LEAST ONE CORRUGATION ALSO PROTRUDING FROM SAID FRONT SIDE, SO AS TO PROVIDE A CONCAVE TRANSVERSELY WIDENED TOP SURFACE OF CONVEX CONTOUR IN THE CREST OF SAID LAST-NAMED CORRUGATION, IN SYMMETRICAL RELATION TO THE PLANE OF SYMMETRY OF THE LATTER WHEREBY THE THEORETICAL RIDGE LINE OF SAID CREST TERMINATES ADJACENT TO SAID TOP SURFACE ON BOTH SIDES OF SAID DEPRESSION BY DIVIDING INTO TWO DIVERGING CONVEX BOUNDARY FOLD LINES FALLING DOWN UPON SPREADING APART TO REACH THE BOTTOM OF SAID TOP SURFACE THEREBY GRADUALLY BROADENING THE LATTER, THE CONVEX FOLDS WHICH CORRESPOND TO SAID CONVEX FOLD LINES CONNECTING SAID TOP SURFACE TO TWO LATERAL CONVEX SURFACE PORTIONS FORMED IN AND PROTRUDING SIDEWISE IN OPPOSITE DIRECTIONS, RESPECTIVELY, FROM EITHER LATERAL FACE OF SAID CORRUGATION, THEREBY FORMING EACH ONE A LATERAL BULGE THEREIN, TWO SUCCESSIVE DEPRESSIONS ADJACENT TO TWO SUCCESSIVE INTERSECTIONS, RESPECTIVELY, ON A SAME CORRUGATION, BEING CONNECTED BY A CONTINUOUS SECTION OF CORRUGATION SO THAT THE LENGTH OF ANY ADJACENT SMOOTH UNCORRUGATED AREA IN A DIRECTION PARALLEL TO SAID CORRUGATION IS LONGER THAN THAT OF ANY ONE OF SAID DEPRESSIONS IN SAID DIRECTION, SAID DEPRESSIONS AT ANY ONE INTERSECTING REGION DEFINING A COMMON INTERSECTION BODY INTERCONNECTING THE INTERSECTING CORRUGATIONS AND PROJECTING FROM SAID FRONT SIDE WHILE BEING HOLLOW ON SAID BACK SIDE AND FORMED WITH FOLDS ALLOWING DEFORMATION OF SAID BODY IN DIRECTIONS SUBSTANTIALLY PARALLEL TO ANY ONE CORRUGATION WITHOUT STRAINING NOR STRESSING THE SURFACE PORTIONS THEREOF LYING BETWEEN SAID FOLDS.