U.S. patent application number 12/452718 was filed with the patent office on 2010-11-11 for fluid container.
Invention is credited to Josef Mikl.
Application Number | 20100282764 12/452718 |
Document ID | / |
Family ID | 39789860 |
Filed Date | 2010-11-11 |
United States Patent
Application |
20100282764 |
Kind Code |
A1 |
Mikl; Josef |
November 11, 2010 |
FLUID CONTAINER
Abstract
A container for a fluid includes a rigid outer shell, an
insulating layer, and at least one inner vessel, which over its
surface is supported by the insulating layer. A robust and
economical solution is obtained by providing that the outer shell
is configured essentially as a single-piece closed container and
that the insulating layer is supported by the outer shell over its
surface.
Inventors: |
Mikl; Josef; (Salzburg,
AT) |
Correspondence
Address: |
DYKEMA GOSSETT PLLC
FRANKLIN SQUARE, THIRD FLOOR WEST, 1300 I STREET, NW
WASHINGTON
DC
20005
US
|
Family ID: |
39789860 |
Appl. No.: |
12/452718 |
Filed: |
July 17, 2008 |
PCT Filed: |
July 17, 2008 |
PCT NO: |
PCT/EP2008/059341 |
371 Date: |
March 2, 2010 |
Current U.S.
Class: |
220/592.27 |
Current CPC
Class: |
C08J 9/0028 20130101;
B65D 88/748 20130101; B65D 88/128 20130101; B65D 90/06 20130101;
C08J 2325/04 20130101; C08J 2201/03 20130101 |
Class at
Publication: |
220/592.27 |
International
Class: |
B65D 81/38 20060101
B65D081/38 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 19, 2007 |
AT |
1147/2007 |
Claims
1-11. (canceled)
12. A container for a fluid, comprising a rigid outer shell which
essentially is configured in a single piece as a closed container,
an insulating layer which is supported by the outer shell over its
surface, and at least one inner vessel which is supported by the
insulating layer over a surface thereof, wherein the insulating
layer contains embedded vacuum insulation panels (VIP).
13. The container according to claim 12, wherein the vacuum
insulating panels (VIP) are located in areas of minimum thickness
of the insulating layer.
14. The container according to claim 12, wherein the insulating
layer is foamed up in situ at least underneath, on top and on the
sides of the inner vessel.
15. The container according to claim 14, wherein the insulating
layer is foamed up in situ inside a protective sheet at least at
one front end of the inner vessel.
16. The container according to claim 14, wherein the insulating
layer comprises at least one body of rigid shape at least at one
front end of the inner vessel.
17. The container according to claim 12, wherein the insulating
layer comprises a plurality of bodies of rigid shape.
18. The container according to claim 12, wherein the inner vessel
comprises fittings which are located at one front end.
19. The container according to claim 12, wherein the inner vessel
has non-circular cross-section which is adapted to a rectangular
cross-section of the outer shell.
20. The container according to claim 12, wherein the outer shell is
configured as a standard container.
21. The container according to claim 12, including at least one
hollow space in a region of the inner vessel for receiving a heat
storing medium.
22. The container according to claim 12, including a closable
maintenance opening in an area of the doors.
Description
[0001] The present invention relates to a container for a fluid,
comprising a rigid outer shell, which essentially is configured as
a single-piece closed container, and an insulating layer, which is
supported over its surface by the outer shell, and at least one
inner vessel, which is supported over its surface by the insulating
layer.
[0002] Transporting goods in containers has gained in importance
due to the simple logistics involved. This is also true for liquids
and gases, that is, fluid materials transported in so-called tank
containers. A conventional tank container is constructed such that
an inner receptacle for receiving the fluid is disposed inside a
frame of the shape of a parallelepiped, which has the standard
dimensions of a container. In many cases it is required to keep the
fluid at a certain temperature. To this end the inner receptacle is
enclosed in an insulating layer. Applying this insulating layer is
relatively expensive, and there is always the danger that the
insulating layer is damaged when the container is filled or
emptied, since it is freely accessible through the interstices of
the frame. A further disadvantage of conventional tank containers
lies in the fact that the inner receptacle must have sufficient
stability in order to withstand the occurring loads. These loads
consist mainly of the weight of the contents and the pressure
forces exerted by interior pressure. In view of these facts
conventional tank containers are heavy and expensive.
[0003] From EP 0 025 792 B there is known a tank container, which
has a thin-walled inner vessel, which on its outside is enclosed by
an insulating layer. The insulating layer--in addition to acting as
a thermal insulator--will also help to support the inner vessel,
which on its own could not sustain the load acting on it. A
container of this kind will solve some of the problems mentioned
and may be designed as a light-weight unit requiring little
material. The critical aspect is, however, that the insulating
layer must transmit the supporting forces of the inner vessel onto
a frame-shaped exterior structure and must thus have relatively
great strength itself. A compromise between insulating capability
and mechanical strength must therefore be made when the insulating
material is chosen. Moreover, manufacture of such containers is
complex and expensive.
[0004] Other known solutions for improving the transport system are
presented in DE 25 41 375 A, in U.S. Pat. No. 3,115,982 A, in DE
712 09 59 U, and in DE 37 02 792 A. All of these solutions are
comparatively costly and provide only insufficient thermal
insulation. Other known solutions are presented in DE 26 36 310 A
and DE 28 56 442 A.
[0005] It is the object of the present invention to avoid the above
mentioned disadvantages and to propose a container, which has a
simple design, is robust and has good insulating properties while
being light-weight. In particular, a great filling volume should be
achieved for given exterior dimensions.
[0006] The invention achieves its object by providing that the
insulating layer contains embedded vacuum insulation panels (VIPs).
It is an essential aspect of the invention that a standard
container can be used as exterior shell. Such containers are
available in large numbers, they are series-manufactured at
relatively low cost and are very robust. A further advantageous
aspect of the invention lies in the fact that the insulating layer
is supported by the exterior shell over its whole surface, and thus
is mechanically subject only to a small pressure load. It is thus
possible to select an insulating material with optimum insulating
properties, as the mechanical properties are less relevant. The
insulating layer is furthermore protected from mechanical damage by
the exterior shell, resulting in long service life of the
container. Depending on given requirements a compromise between
thermal insulation and volume of the inner vessel may be found.
[0007] A further important aspect of the invention lies in the fact
that no holding or fixing means will be required, which would
thermally connect the inner vessel and the exterior shell, and
would thus present heat bridges degrading the insulation
properties.
[0008] The aim of a large filling volume is achieved in particular
by reinforcing the insulating layer with vacuum insulation panels
(VIPs). VIPs are extensively used where a maximum of insulation is
required. Known applications of VIPs are in refrigerating
equipment, mobile cooling boxes, refrigerated walls for
cold-storage warehouses and refrigerated vehicles. VIPs consist of
an envelope which seals against gas and water-vapour, and a filling
material inside the envelope, the envelope being sealed after
having been evacuated to a partial vacuum. Such vacuum insulation
panels are for instance described in DE 198 14 271 A, DE 298 09 807
U, or DE 298 11 136.5 A. Usually silicic acid is used as filling
material, which is pressed into a plate, which is then sealed in
vacuum into a gas- and water-vapour-tight sheet.
[0009] Other known filling materials for making VIPs are glass
fibres, open-cell plastic foams, silicic acid and degassed PUR-foam
from recycled refrigerators. It is also known to pour loose filling
material into an envelope which is then evacuated, thereby
imparting stability to the panel.
[0010] Metal foils or plastic sheets or a combination of both may
be used for the envelopes. Essential properties of vacuum panels
and their filling materials include low thermal conductivity,
pressure resistance, thermal stability, high heat capacity and
constancy of shape. By using VIPs in critical areas of little wall
thickness, i.e. usually in the central regions of the walls, an
inner vessel with large diameter may be employed, since the
required insulation can be achieved with comparatively thin
walls.
[0011] Particularly simple manufacture and a very good insulation
layer will be achieved if the insulation layer is essentially
foamed up in situ. Only at the front ends of the inner vessel it
may be of advantage if the inner vessel is kept freely accessible
for maintenance work. In this context it is of special advantage if
the required fittings, such as valves, filling openings, man holes
etc. are located in this area so as to be freely accessible. In
order to ensure a proper insulation effect suitably shaped bodies
of insulating material are provided, which will complete the
insulation layer in this area. Alternatively, in situ foamed
insulation bodies may be provided at the front end areas, which are
provided inside of foils, however, to prevent them from sticking to
the container doors or fittings.
[0012] An alternative solution proposes to build up the complete
insulation layer from a multitude of suitably shaped bodies. This
would permit removal of the inner vessel if required, and use of
the container forming the outer shell for other purposes.
[0013] A particular advantage of the solution according to the
invention lies in the fact that the inner vessel need not
necessarily have circular cross-section, even if it is designed as
a pressure vessel. It is entirely possible and feasible to
configure the inner vessel with rectangular cross-section with
rounded-off corners to avoid wasted space and achieve greater
volume.
[0014] Preferentially, a hollow space is provided in the region of
the inner vessel, which space can be filled with a heat storing
medium. Even very good insulation may not be sufficient to maintain
a certain required temperature level during long transports or for
critical goods. To avoid the necessity of special cooling or
heating equipment a heat storing medium may be provided within the
insulating layer, which helps to keep temperature within given
limits. In the case of refrigerated transports ice or dry ice may
be used, for transports where temperature of the goods must not
fall below a certain threshold, hot water may be used as heat
storing medium, or a chemical agent having a phase transition in a
suitable temperature interval. A hollow space in the insulating
layer may be provided for receiving the heat storing medium. It is
of particular advantage, however, if the heat storing medium is
contained in yet another flexible vessel, which is disposed within
the insulating layer together with the inner vessel.
[0015] In the region of the doors a closable maintenance opening
may be provided. This will permit access to the fittings without
the need for opening the doors. The doors themselves possibly may
be permanently closed, i.e. welded, since operational handling may
be effected via the maintenance opening. If required, more
maintenance openings may be provided at other points, for instance
on the topside of the container.
[0016] The invention will now be described in more detail, with
reference to the embodiment shown in the enclosed drawings. There
is shown in
[0017] FIG. 1 a longitudinal section along a horizontal plane of a
container according to the invention;
[0018] FIG. 2 a section along line II-II of FIG. 1; and
[0019] FIG. 3 a section along line III-III of FIG. 1.
[0020] The container of FIG. 1 comprises an outer shell 1, which is
configured as a standard container. Inside the outer shell 1 there
is an inner vessel 2, which is a thin-walled stainless steel tank,
having a wall thickness of for instance 0.8 mm, depending on static
requirements. The inner vessel 2 lies with its whole surface
against an insulating layer 3, which in turn is supported by the
inside of the outer shell 1. The insulating layer 3 is foamed-up in
situ as one piece, and is made of polyurethane with a weight of
30-80 kg/m.sup.3. At a front end of the outer shell 1 doors 6 are
provided, as is customary in containers, to permit access to the
interior. In this area fittings are provided, such as valves 4 or a
man hole 5. In the area between the doors 6 and the inner vessel 2
especially shaped bodies 7 of insulating material are provided to
complete the insulating layer 3 in this area. A rinsing line
(CIP-line) 8 is provided for cleaning the inner vessel 2.
[0021] Reference number 11 indicates an embedded vacuum insulation
panel (VIP) in the region of a side wall. Analogously, such panels
could be used in the other side walls or at the top or bottom. The
embedded panels are provided only in regions where the insulating
layer 3 has small thickness, and may be kept small if the inner
vessel 2 has circular cross-section. This will result in optimum
cost-effectiveness.
[0022] Within the door 6 a closable maintenance opening 10 is
provided, which is used for inspection and for filling and
draining.
[0023] According to FIG. 3 the inner vessel 2 does not have
circular cross-section but is essentially rectangular with
rounded-out corners. In this way maximum filling volume will be
obtained.
[0024] The present invention permits the manufacture of tank
containers, which are economical, robust and have optimum
insulation effect.
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