Patent attributes
A quasi-cylindrical cargo container is formed of a plurality of rigid, curved panels together forming first and second semi-cylindrical shells, and a plurality of rigid, flat extension panels bridging the first and second semi-cylindrical shells. A method of manufacturing the container includes forming the first and second semi-cylindrical shell from the curved panels, forming the quasi-cylindrical shell from the first and second semi-cylindrical shells and the flat extension panels, forming collars conformably encompassing the quasi-cylindrical shell, constricting the collars to compress joints formed at abutting edges of pairs of adjacent panels, rolling the shell and collars sequentially to bring the joints to a lower position, welding inside seams of the joints when at the lower position, removing the collars, rolling the shell sequentially to bring the joints to an upper position, and welding outside seams of the joints when at the upper position.
