The present invention concerns a pressure container with a jacket comprising partial cylindrical jacket shells that are located parallel next to each other and define a bead in the longitudinal direction, whose end faces are closed off by a curved bottom. Pressure containers with partially cylindrical jacket shells whose cross section resembles an octagon are known, for example, from DE-A-36 06 247, DE-A-31 25 963, DE-A-29 51 554 and EP 1067326 B1. Such pressure containers are especially suitable as transport container for road vehicles, such as tank semitrailers, or for tank container arrangements that require containers which should make especially effective use of a structural space with reduced height and ensure high compressive strength at the same time as a weight-economizing use of material.
The best compressive strength is afforded by a circular cylindrical cross section, although this makes inadequate use of a rectangular cross section of the structural space with long sides situated horizontally. Such a cross section of the structural space with reduced height is also filled up with several pressure-tight full cylindrical containers alongside each other (
Therefore, pressure containers according to the preamble of claim 1 have been developed. These afford substantial advantages in regard to space utilization over full cylindrical pressure containers and are superior in pressure engineering to box-shaped or oval tank cross sections that are used in particular for petroleum products; however, they have worse utilization of space. Especially for long pressure containers it is helpful and sometimes also required to provide tractive elements between the partially cylindrical shells to join the beads together in terms of pressure engineering. In this case, a tractive element in the shape of a flat wall that projects into or passes through the upper or lower bead region is especially easy to fabricate (see, e.g., EP 1067 326 B1). The partially cylindrical shells are then placed against this wall, abutting with each other, and joined or welded to it.
The problem is to further improve such pressure containers with a jacket of partially cylindrical jacket shells in terms of their space utilization and/or compressive strength.
This problem is solved by a pressure container according to claim 1, in which a shell element is provided that joins together the jacket shells and the tractive element. This shell element then closes the bead region—as a roof element on the top side and a floor element on the bottom side—and forms with these elements or the enclosed regions a profiled beam structure in the crotch region, which provides additional stabilizing action both against internal and external pressure loads, and against overturning loads.
For applications in which a double jacket is required, such as for containers designed for storage of hazardous goods, without having special structural features such as catching troughs, the arrangement of claim 2 is used.
The shape stability of the shell element is further enhanced by cambers (meaning here a cylindrical/prismatic camber about a lengthwise axis) or edges (claim 3).
Claim 4 specifies closing the region resulting from the different opening contours of the cambered floor and the jacket (the jacket shells) with a flat spandrel element running perpendicular to the lengthwise axis of the tank.
A further stabilization occurs if the spandrel elements are also each joined to the end faces of the tractive element, according to claim 5.
The present invention concerns a pressure container with a jacket comprising partial cylindrical jacket shells that are located parallel next to each other and define a bead in the longitudinal direction, whose end faces are closed off by a curved bottom. Pressure containers with partially cylindrical jacket shells whose cross section resembles an octagon are known, for example, from DE-A-36 06 247, DE-A-31 25 963, DE-A-29 51 554 and EP-A 1 326. Such pressure containers are especially suitable as transport container for road vehicles, such as tank semitrailers, or for tank container arrangements that require containers which should make especially effective use of a structural space with reduced height and ensure high compressive strength at the same time as a weight-economizing use of material.
The best compressive strength is afforded by a circular cylindrical cross section, although this makes inadequate use of a rectangular cross section of the structural space with long sides situated horizontally. Such a cross section of the structural space with reduced height is also filled up with several pressure-tight full cylindrical containers alongside each other (
Therefore, pressure containers according to the preamble of claim 1 have been developed. These afford substantial advantages in regard to space utilization over full cylindrical pressure containers and are superior in pressure engineering to box-shaped or oval tank cross sections that are used in particular for petroleum products; however, they have worse utilization of space. Especially for long pressure containers it is helpful and sometimes also required to provide tractive elements between the partially cylindrical shells to join the beads together in terms of pressure engineering. In this case, a tractive element in the shape of a flat wall that projects into or passes through the upper or lower bead region is especially easy to fabricate. The partially cylindrical shells are then placed against this wall, abutting with each other, and joined or welded to it.
The problem is to further improve such pressure containers with a jacket of partially cylindrical jacket shells in terms of their space utilization and/or compressive strength.
This problem is solved by a pressure container according to claim 1, in which a shell element is provided that joins together the jacket shells and the tractive element. This shell element then closes the bead region—as a roof element on the top side and a floor element on the bottom side—and forms with these elements or the enclosed regions a profiled beam structure in the crotch region, which provides additional stabilizing action both against internal and external pressure loads, and against overturning loads.
For applications in which a double jacket is required, such as for containers designed for storage of hazardous goods, without having special structural features such as catching troughs, the arrangement of claim 2 is used.
The shape stability of the shell element is further enhanced by cambers (meaning here a cylindrical/prismatic camber about a lengthwise axis) or edges (claim 3).
Claim 4 specifies closing the region resulting from the different opening contours of the cambered floor and the jacket (the jacket shells) with a flat spandrel element running perpendicular to the lengthwise axis of the tank.
A further stabilization occurs if the spandrel elements are also each joined to the end faces of the tractive element, according to claim 5.
In terms or pressure engineering and fabrication engineering, a spandrel element according to claim 6 is advantageous; especially when an outer contour region follows the inner peripheral contour of the cambered bottom, that is, when it can be inserted into the latter, and has an inner contour region that projects inwardly into the interior of the container beyond the bead region, so that the peripheral contour at the end faces of the jacket shell always travels along the facing surface of the spandrel element. In this way, the jacket formed from the jacket shells can always be set cleanly by its end faces against the open end of the cambered bottoms, in which the corresponding spandrel elements are set flush with the edge, without this requiring additional fitting or notching work. The contour regions meet at an acute angle in the apex and base regions of the jacket shells and provide there an additional reinforcement advantageous to the pressure engineering, absorbing the peak stresses occurring there on account of the internal pressure of the container.
According to claim 7, the reinforcement is further improved and the peak stresses are further absorbed by providing riblike extensions at the ends of the spandrel element, which basically follow the common peripheral contour of bottom and jacket shell and go beyond the apex or base region where the peak stresses occur.
According to claim 8, the jacket shells have circumferential segments of different curvature. In particular, the curvatures in the upper and lower bead region are smaller—that is, with broader radius of curvature—than the curvatures of the circumferential segments that join the top apex to the bottom base region of the jacket shells and form the side waste regions of the container Thanks to this feature, the depth of the bead formed at the seam between the partial cylindrical jacket shells extending in the lengthwise direction can be reduced, thereby increasing the useful volume of the pressure container without substantially reducing the compressive strength. At the same time, it is easier to attach a curved bottom whose opening encompasses this smaller bead region, since the difference in cross section between the opening cross section of the bottom and that of the jacket is smaller.
In addition, the curvatures in the upper and lower bead region can also differ from each other. That is, the bead depth is different at the lower side of the container than at the upper side. A greater curvature—narrower radius—leads to a deeper bead and a smaller curvature—larger radius—to a shallower bead. A shallower bead in the lower region can be helpful, for example, for the emptying of the adjacent base regions of the individual jacket shells without any remainders. A deeper bead, on the other hand, confers a greater shape stability on such a pressure container in this region, so that it can be supported on beams running along the tank base—such as the lengthwise girders of a semitrailer, or the loading skids of a hook lift system.
According to claim 9, it is also possible to provide different wall thicknesses per section of the circumference.
Claim 10 concerns a transport container arrangement that is provided with a pressure container according to the invention.
Sample embodiments of the present invention are described hereafter by means of the drawings. There are shown:
The pressure container 1 shown in
Each of the jacket shells 2, 4 has circumferential segments of different curvature 2a, 2b, 2c and 4a, 4b, 4c. The circumferential segments 2a and 4a run from the juncture with the flat wall 6 to the apex line 7 of the particular jacket shells 2 and 4. Starting from the apex lines, the circumferential segments 2b and 4b run to the lower base lines 9 of the jacket shells 2, 4, from which the circumferential segments 2c and 4c run to the flat wall 6. The circumferential segments 2b and 4b have a radius of curvature of 600-1300 mm in the waist region, while the upper and lower circumferential segments 2a, 2c and 4a, 4c have a radius of curvature of 600-3000 mm.
These radius ranges are indicated for tank containers or vehicles with a maximum width of 2600 mm. For other dimensions, correspondingly different radius ranges and relations can be indicated, being adapted to the actually existing outside dimensions of the tank containers or vehicles (train, truck).
The circumferential segments 2a and 4a form an upper bead region 8 and the circumferential segments 2c and 4c a lower bead region 10. The upper end 12 and the lower end 14 of the flat wall 6 project into the bead regions 8 and 10; the lower end 14 as far as the plane defined by the base lines 9 of the jacket shells 2 and 4 and the upper end 12 beyond the plane defined by the apex lines 7 of the jacket shells 2 and 4. Both ends 12 and 14 are provided with a beveling 12a and 14a for stabilization. The flat wall 6 is provided with a passage opening 50, reinforced with a collar 52.
The ends of the jacket shells 2 and 4 are closed with curved bottoms 16 and 18 (
In order to balance out and close the difference in cross section between the bead regions 8 and 10 and that of the oval bottom cross section, spandrel elements 24 and 26 are provided there, being arranged as flat metal sheets transversely to the longitudinal direction. In the sample embodiment depicted, the lower spandrel elements 26 are each provided with an outer contour region 28 (
At the upper spandrel element 24, the outer contour region 34 likewise follows the straight upper circumferential contour segment of the bottoms 16 and 18 and extends by its inner contour regions 36 to the ends 38, which like the lower spandrel elements 26 end in the apex regions (apex lines 7). While the lower spandrel element 26 is arranged entirely inside the bottom contour 1, the outer contour region 34 of the upper spandrel element 24 projects beyond the bottom contour and extends outside of it at roughly the same height as the beveling 12a.
Openings 40 are provided in the jacket shells 2 and 4, into which typical container ports such as manhole, filling ports, vent ports, and safety valve ports are inserted (see
In the container apex an additional shell element 42 is provided, which is welded at least for sections to the jacket shells 2 and 4 at its side edges 44 in the apex regions and to the upper spandrel element 24 at its end faces 46. An edging 47 extends in the middle of the shell element 42, which comes to lie against the beveling 12a and is fastened to this via plug welds 48. In this way, the circumferential segments 2a, 4a, the upper end 12 of the flat wall 6 with the beveling 12a and the shell element 42 form a stabilizing longitudinal girder unit, which is closed at its ends by the upper spandrel elements 24 and thus further stabilized.
The jacket shells 2 and 4 in the sample embodiment depicted (
The double jacket 5 is left out in
In the sample embodiment shown, the ends 32, 38 of the spandrel elements 24 and 26 extend in the base and apex regions of the jacket shells 2 and 4, which at the same time also form the transitions at which the straight circumferential segments of the bottoms 16 and 18 pass into the curved circumferential segments. This point is therefore especially critical in terms of pressure engineering. In order to further reduce the peak stresses occurring there, especially under internal pressure, a riblike prolongation 132a, 132b is shown in the sample embodiment of
In configuration a (left), the spandrel element 24 is larger as a whole and projects by the region 132a beyond the left apex line 7. In configuration b (right), only one cover strap 132b is provided, which extends beyond the apex line 7.
There are also configurations (not shown) in which the jacket shells not only have independent radii of curvature, but also different wall thicknesses are provided for segments of the circumference. This can equalize the generally higher compressive stresses for the broader (larger) radii of curvature. This stress-optimized design enables further weight savings and higher compressive loads.
For those containers that are provided with a double jacket 5, this outer jacket 5 can also be used as an active structural element to absorb the compressive loads. This presupposes a force-transmitting coupling between inner container and outer container. This is accomplished, for example, by a supporting girder (not shown) provided between the inner and outer walls, enabling a pointlike or linear force transmission between the container walls. At especially vulnerable points, additional node sheets can also be provided for the coupling (not shown), which make possible an especially effective shifting of peak loads occurring on the inner wall to the outer wall.
Further variants and configurations of the present invention will be apparent from the claims to the person versed in the art.
Number | Date | Country | Kind |
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10 2008 064 364.5 | Dec 2008 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP09/09203 | 12/21/2009 | WO | 00 | 10/11/2010 |