Laminated seal structure for storage tanks employing floating roofs

Claim 1

IN A TANK FOR STORING LIQUIDS SUCH AS PETROLEUM PRODUCTS, INCLUDING AN UPSTANDING SUBSTANTIALLY CYLINDRICAL SIDE WALL, AND A FLOATING ROOF ARRANGED IN SAID TANK AND INCLUDING AN UPSTANDING SUBSTANTIALLY CYLINDRICAL WALL STRUCTURE SPACED RADIALLY INWARDLY FROM SAID TANK SIDE WALL AND DEFINING AN UPSTANDING SUBSTANTIALLY ANNULAR SPACE THEREBETWEEN; SEALING MECHANISM FOR SAID ANNULAR SPACE COMPRISING A SUBSTANTIALLY ANNULAR RADIALLY THIN SEALING ELEMENT ARRANGED IN SAID ANNULAR SPACE AND CARRIED BY SAID WALL STRUCTURE AND MOVABLE THEREWITH WITH RESPECT TO SAID TANK SIDE WALL; SAID MECHANISM INCLUDING A SERIES OF UPRIGHT SEGMENTAL ANNULAR METAL-LIKE CIRCUMFERENTIALLY LIMBER SHOE MEMBERS ARRANGED IN CLOSELY SPACED-APART END-TO-END RELATION ABOUT A VERTICAL AXIS, AN ANNULAR FABRIC ENVELOPE FOR CLOSING SAID SPACE AND HAVING AN INTERMEDIATE ANNULAR STRIP PORTION SECURED TO SAID SHOES AND ENGAGING SAID SIDE WALL AND ALSO HAVING A LOWER PORTION LOOPED DOWNWARDLY AND RADIALLY INWARDLY FROM SAID ANNULAR STRIP PORTION SAND SECURED TO A LOWER CIRCUMFERENTIAL PORTION OF SAID CYLINDRICAL WALL STRUCTURE, SAID ANNULAR FABRIC ENVELOPE HAVING AN UPPER PORTION EXTENDING UPWARDLY AND RADIALLY INWARDLY FROM SAID AN-