Patent ID: 7111750

Claim:
A substantially rectangular fluid storage tank, said fluid storage tank having a length, width, height, first and second ends, first and second sides, top and bottom, said fluid storage tank comprising: (a) an internal frame structure, said frame structure comprising: (1) a plurality of first plate girder ring frames having inner sides disposed to the interior of said fluid storage tank and outer sides, said first plate girder ring frames running along the width and height of said fluid storage tank and spaced along the length of said fluid storage tank, (2) a first plurality of truss structures running along the width and height of said fluid storage tank and spaced along the length of said fluid storage tank, each one of the said first truss structures (i) corresponding to one of the said first plate girder ring frames and (ii) disposed in the plane of and inside one of the said first plate girder ring frames, said first plurality of truss structures thereby supporting the inner sides of said first plate girder ring frames, (3) a plurality of second plate girder ring frames having inner sides disposed to the interior of said fluid storage tank and outer sides, said second plate girder ring frames running along the height and length of said fluid storage tank and spaced along the width of said fluid storage tank, wherein the intersection of said plate girder ring frames forms a plurality of attachment points, thereby forming one integrated internal frame structure; and (b) a plate cover surrounding said internal frame structure, said plate cover having an inner side and an exterior side, said inner side of said plate cover disposed to the outer sides of said first and second ring frames.