A trailer configured to lower an overall center of gravity. Said trailer comprises a tank, a wheel assembly, a kingpin assembly, a height, a length. Said tank comprising a cavity contained within a lower body, an upper body, a transitioning body, a front end, and a rear end. Said tank comprising a lower center of gravity, an upper center of gravity and said overall center of gravity. Said lower body comprising said lower center of gravity, a lower body ground clearance, a lower body length and a lower body height. Said upper body comprising said upper center of gravity, an upper body ground clearance, said height, and an upper body length. Said tank comprising said length, a height equal to said height, and a ground clearance equal to said lower body ground clearance. Said transitioning body comprising a transitioning body length.

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.

A transportation trailer can include a cargo tank with a shell that includes an outer wall, an inner wall, and an insulating core between the outer wall and the inner wall. The shell can be unsupported by structural rings, and the cargo tank can be a frameless cargo tank. The cargo tank can be formed by decoiling respective coils of inner-wall material, outer-wall material, and insulating-core material, joining the inner-wall material, the insulating-core material, and the outer-wall material to form a sandwich-type panel, and welding the sandwich-type panel to form the shell.

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.

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.

A vehicle body. The vehicle body comprises a fluid transfer system integrated within the vehicle body. The fluid transfer system comprises a fluid evacuation system comprising a first fluid storage container, a fluid refill system comprising a second fluid storage container, a sensing system coupled to the fluid evacuation system and the fluid refill system, and a control circuit coupled to the sensing system, the fluid evacuation system and the fluid refill system. The control circuit is configured to (1) determine an amount of a first fluid in the first fluid storage container based on a first signal from the sensing system, and (2) determine an amount of a second fluid in the second fluid storage container based on a second signal from the sensing system.

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.

A vehicle body. The vehicle body comprises a fluid transfer system integrated within the vehicle body. The fluid transfer system comprises a fluid evacuation system comprising a first fluid storage container, a fluid refill system comprising a second fluid storage container, a sensing system coupled to the fluid evacuation system and the fluid refill system, and a control circuit coupled to the sensing system, the fluid evacuation system and the fluid refill system. The control circuit is configured to (1) determine an amount of a first fluid in the first fluid storage container based on a first signal from the sensing system, and (2) determine an amount of a second fluid in the second fluid storage container based on a second signal from the sensing system.

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.

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.