Insulated transportation trailer

1. A transportation trailer comprising:

a cargo tank having a substantially cylindrical shell;

the substantially cylindrical shell including:

a rigid outer wall;

an inner wall formed from metal; and

an insulating core disposed between the rigid outer wall and the inner wall, the insulating core providing structural support to the substantially cylindrical shell,

wherein the cargo tank does not include structural rings connected to the inner wall;

wherein the cargo tank does not include a frame extending from a front end of the substantially cylindrical shell to a rear end of the substantially cylindrical shell.

2. The transportation trailer of claim 1 , further comprising:

a front mounting assembly coupled to a front end of the cargo tank; and

a rear mounting assembly coupled to a rear end of the cargo tank;

wherein the front mounting assembly is spaced apart from the rear mounting assembly and the transportation trailer does not include a frame member extending between the front mounting assembly and the rear mounting assembly to support the cargo tank.

3. The transportation trailer of claim 1 , wherein the substantially cylindrical shell does not include a substantially circumferential weld seam.

4. The transportation trailer of claim 3 , wherein the substantially cylindrical shell is formed from a plurality of panels joined together by substantially longitudinal weld seams, each of the panels including an outer wall portion, an inner wall portion, and an insulating core portion between the inner wall portion and the outer wall portion.

5. The transportation trailer of claim 3 , wherein the substantially cylindrical shell is formed as at least one continuous spiral of outer-wall material, inner-wall material, and insulating-core material.

6. The transportation trailer of claim 5 , wherein the at least one continuous spiral includes an inner spiral formed from the inner-wall material, an outer spiral formed from the outer-wall material, and an insulating spiral formed from the insulating-core material.

7. The transportation trailer of claim 1 , wherein the rigid outer wall is a sprayed-on outer layer of the substantially cylindrical shell.

8. The transportation trailer of claim 1 , wherein the insulating core includes a closed-cell foam material.

9. The transportation trailer of claim 1 , wherein at least one of the inner wall and the rigid outer wall is formed from stainless steel.

10. The transportation trailer of claim 9 , wherein the at least one of the inner wall and the rigid outer wall is formed from stainless steel of gauge 20 or thinner.

11. The transportation trailer of claim 1 , wherein the cargo tank is configured to transport liquids.

12. A transportation trailer comprising:

a cargo tank that includes:

an inner wall;

an outer wall; and

an insulating core disposed between the outer wall and the inner wall;

the inner wall, the outer wall and the insulating core forming a sandwich-type shell that includes at least one of:

a plurality of sandwich-type panels connected by a plurality of substantially linear longitudinal welds; and

a continuous spiral of at least one of the inner wall, the outer wall, and the insulating core, joined with a continuous spiral weld;

the sandwich-type shell not being supported by structural rings; and

the cargo tank being a frameless cargo tank.

13. A method of forming a cargo tank having a substantially cylindrical shell with a sandwich-type construction, the method comprising:

providing a first coil of outer-wall material;

providing a second coil of insulating-core material;

providing a third coil of inner-wall material;

decoiling the outer-wall material, the insulating-core material, and the inner-wall material from the first, second, and third coils, respectively;

joining the insulating-core material to the inner-wall material and to the outer-wall material to form at least one sandwich-type panel;

welding the at least one sandwich-type panel to form the substantially cylindrical shell, wherein the insulating core provides structural support to the substantially cylindrical shell;

not including structural rings connected to the inner-wall material after the substantially cylindrical shell is formed; and

not providing a frame extending from a front end of the substantially cylindrical shell to a rear end of the substantially cylindrical shell after the substantially cylindrical shell is formed.

14. The method of claim 13 , wherein forming the at least one sandwich-type panel includes forming a plurality of sandwich-type panels; and

wherein welding the at least one sandwich-type panel includes welding the plurality of sandwich-type panels using substantially linear longitudinal welds.

15. The method of claim 14 , further comprising:

before welding the at least one sandwich-type panel, inserting at least one weld tab between the inner-wall material and the outer-wall material along at least one longitudinal edge of the at least one sandwich-type panel;

wherein welding the at least one sandwich-type panel includes welding the at least one sandwich-type panel adjacent to the at least one weld tab.

16. The method of claim 13 , wherein the outer-wall material, the insulating-core material, and the inner-wall material are decoiled in at least one continuous spiral; and

wherein welding the at least one sandwich-type panel includes welding at least one continuous spiral seam.

17. The method of claim 13 , wherein the formed cargo tank does not include a substantially circumferential weld seam.

18. The method of claim 13 , wherein the at least one sandwich-type panel exceeds 66 feet in length.

19. A transportation trailer comprising:

a cargo tank having a substantially cylindrical shell;

the substantially cylindrical shell including:

an outer wall;

an inner wall; and

a structural insulating core disposed between the outer wall and the inner wall; and

the transportation trailer:

not including structural rings connected to the inner wall; and

not including a frame extending from a front end of the substantially cylindrical shell to a rear end of the substantially cylindrical shell.

20. A transportation trailer comprising:

a cargo tank having a substantially cylindrical shell;

the substantially cylindrical shell including:

a rigid outer wall;

an inner wall formed from metal;

an insulating core disposed between the rigid outer wall and the inner wall, the insulating core providing structural support to the substantially cylindrical shell;

a front mounting assembly coupled to a front end of the cargo tank; and

a rear mounting assembly coupled to a rear end of the cargo tank;

wherein the front mounting assembly is spaced apart from the rear mounting assembly and the transportation trailer does not include a frame member extending between the front mounting assembly and the rear mounting assembly to support the cargo tank.

21. A transportation trailer comprising:

a cargo tank having a substantially cylindrical shell;

the substantially cylindrical shell including:

a rigid outer wall;

an inner wall formed from metal; and

an insulating core disposed between the rigid outer wall and the inner wall, the insulating core providing structural support to the substantially cylindrical shell,

wherein:

the substantially cylindrical shell does not include a substantially circumferential weld seam, and

the substantially cylindrical shell is formed from a plurality of panels joined together by substantially longitudinal weld seams, each of the panels including an outer wall portion, an inner wall portion, and an insulating core portion between the inner wall portion and the outer wall portion.