GB2208850A

GB2208850A - Transport container

Info

Publication number: GB2208850A
Application number: GB8819740A
Authority: GB
Inventors: Joseph Patrick Thomas Dempsey
Original assignee: TRIDENT LINER SERVICES Ltd
Current assignee: TRIDENT LINER SERVICES Ltd
Priority date: 1987-08-20
Filing date: 1988-08-19
Publication date: 1989-04-19
Also published as: GB8719667D0; GB8819740D0

Abstract

There is disclosed a transportation container, and a combination of a transportation container and a transport vehicle, (11, 12) wherein the container is in the form of a flexible bag (15) of liquid impervious flexible material which can be secured to the container, for example by means of a harness (22). The use of a flexible container for transporting fluids allows the bag, when empty, to be rolled or folded to a small volume and for return to its origin. The harness may comprise loops (23) and straps (24), and the bag may be made up of strips of rubber or plastics material. <IMAGE>

Description

TRANSPORT CONTAINERS This invention relates to transport containers and in particular to containers for the transport of liquids in bulk.

Conventionally transportation of liquids in bulk is effected using purpose built tanker vehicles. Such vehicles may be road vehicles, i.e tanker lorries or tanker trailers to be pulled by tractor vehicles, or they may be rail vehicles. In either case the container itself comprises a relatively large steel cylinder which is carried on the chassis of the road or rail vehicle. Such vehicles are necessarily costly to manufacture and run, and are therefore only purchased by companies or organisations having sufficient demand for the transportation of liquids in bulk to justify the expense involved.A vehicle of this type is satisfactory for use in transporting the same liquid time and time again, but if differing liquids which should not be mixed together, e.g. milk, oil, chemicals, wine then either several different vehicles are required or a time-consuming, costly and often difficult and/or dangerous cleaning operation must be performed between changes of liquid to be transported. If a particular vehicle is used to carry only one type of liquid so as to avoid the necessity for cleaning between consecutive journeys, then it is usually the case that a journey in one direction may be made with the vehicle full but the journey in the opposite direction has to be made with the vehicle empty as it returns for a new load. This adds considerably to the cost of transportation of the liquid concerned.

It is an object of the present invention to provide a transport container, the use of which avoids, at least to a substantial extent, the abovementioned disadvantages.

The invention provides a transport container for the transportation of liquids in bulk comprising a bag of a liquid impervious flexible material, the bag having closable inlet means whereby a liquid may be introduced into or discharged from it and being shaped so as to be capable of being formed into a small package when empty. The bag can be shaped to lie flat when empty to enable it to be rolled into a small-volume package. Alternatively the bag can be shaped so that, when empty it can be folded to form a small volume package.

The invention also provides a transport vehicle for the transportation of liquids comprising a support and a transport container mounted thereon, said transport container comprising a bag of a liquid impervious flexible material, the bag having closable inlet means whereby a liquid may be introduced into or discharged from it, and being shaped so as to be capable of being formed into a small package when empty.

Preferably said bag is of a rubber and/or plastics material, and may comprise two substantially rectangular sheets of material which overlie each other and are joined to each other along their corresponding edges.

Preferably, however; the bag is made from a number of elongate strips of material which are arranged side-by-side, seamed together to form a hollow cylinder and then seamed along their mutual ends to form the container. Typically, from six to eight strips can be used. At two corners of the container drain valves can be mounted so that after compression of the "empty" bag has been compressed, as by rolling, to occupy a small volume any liquid remaining within the container can be vented from such connections.

The transport vehicle may also comprise securing means adapted to secure said vehicle chassis. The securing means may comprise a harness, which may comprise a plurality of loops adapted to pass around said bag and a plurality of straps attached to said loops.

Preferably the straps are a relatively tight fit on the bag so that when the bag is filled the material of the bag between adjacent straps extends outwardly from the strap positions, each strap therefore defining an inwardly directed ridge within the bag, thus tending to reduce liquid surge within the bag.

Preferably each loop has two or more straps attached thereto on each side and extending to the support on that side. One of the pair extending forwardly and downwardly from its attachment point on the loop and the other of the pair extending rearwardly and outwardly from its attachment point of the loop.

Two or more longitudinally extending loops can be provided to extend lengthwise of the bag and each loop can have, at each end of its upper run a downwardly extending strap which connects with the support. The longitudinally extending loops and the transversely extending loops can be connected together where they cross. The portions of the transverse loops between such interconnection points on top of the bag when in use can be of greater breaking strain than the remainder of the transverse loops as it is these portions of the loops which take the greatest strain when surge of liquid within the bag occurs.

In relation to a bag which is 12 metres in length to suit a popular size of road vehicle there can be six transverse loops arranged equidistantly along the length of the bag. More than six loops are possible, but complicate the structure and make it less easy for the driver to handle.

Preferably said support is a load platform and attachment means for said straps may be provided on said load platform. Said load platform may be rectangular and said attachment means may be provided adjacent the sides of sai platform. Said vehicle may be a road-going vehicle and may be a trailer adapted for articulated connection to a tractor vehicle.

The vehicle could also be a rail vehicle or an aircraft.

The invention will now be further described with reference to the accompanying drawings in which: Fig. 1 is a perpsective view from the rear of a preferred embodiment of vehicle of the invention; Fig. 2 is a plan view of a second embodiment of vehicle of the invention; and Fig. 3 is a longitudinal fragmentary cross-section on an enlarged scale of part of the bag of either embodiment.

Referring now to Fig. 1 there is shown a transport vehicle 10 of the road-going type. The vehicle 10 comprises a tractor vehicle 11 and a trailer 12 in articulated connection with each other.

The trailer 12 has a rectangular load platform 13 and a plurality of attachment devices 14 are provided at the sides of the platform 13. On the load platform is a bag 15 of flexible liquid impervious material such as rubber. The bag 15 is formed of two rectangular sheets 16,17 which overlie each other and are joined at their edges along 7.5 cm end seams 18 and 5cm side seams 19. The bag 15 may be for example approximately 12.2 metres in length and of approximately 23.5 cu metres capacity. In that case the bag 15 would be formed of two sheets 16,17 of approximate dimensions 12.2. x 2.5 metres which lie flat when the bag 15 is empty. In this condition the bag 15 may be rolled up and stored in any suitable location on the vehicle 10, for example in a locker 20. The bag 15 is also provided with one or more closable inlets 21 in order that liquid can be introduced into or be discharged from the bag 15, and for venting and cleaning purposes.

Instead of the bag being made from a pair of superposed sheets, it can be made from a plurality of strips of material joined side-by-side to form a hollow tube and then joined across the ends to form the container. The overall total length of the container will be about 12.2 metres in order to be accommodated on a popular size of flat bed vehicle.

Of course, instead of using a flat bed vehicle a vehicle having pivotable side walls can be used, but these have not been shown in Fig. 1 in order to illustrate details of the construction.

To secure the bag 15 on the load platform 13 a harness 22 is provided. The harness 22 comprises a plurality of loops 23, six being shown in this embodiment, which pass around the bag 15 transversely of the vehicle 10. These loops 23 assist in maintaining the integrity of the bag 15 as the vehicle 10 in in transit, i.e preventing bursting of the side seams 19 and reducing the tendency of the liquid to surge within the bag 15. Reference will now here be made to Fig. 3 which is a longitudinal cross-section of a portion of the bag between loops 25. Several of the loops 23 are shown in cross-section and the desired shape of the bag 15 between those loops is illustrated. It will be seen that the bag 15 bulges outwards or "pillows" between each adjacent pair of straps 23 each of which strap 23 is coincident with an inwardly directed annular ridge 29.The combination of the ridges 29 and the outward bulges 28 give the internal surface of the bag a corrugated effect which reduces the tendency for liquid to surge within the tank during acceleration and deceleration of the vehicle. The volume of liquid which should be loaded into the bag 15 is quite physical, because over filling can strain the material thus reducing its strength, and under filling can cause floppiness which will increase surge problems. For example, for a bag having a nominal volume of 23 cu metres the maximum filling volume is stated to be 25 cu metres and the minimum filling volume 21 cu metres. Because this is a relatively narrow range it is relatively easy to ensure that even at the minimum filling level of 21 cu metres there is still the pillowing effect caused by the straps 23 being equal to or slightly smaller in diameter than the bag in its full condition.The loops 23 are secured to the vehicle 10 by means of straps 24, there being two straps 24 attached to each side of each loop 23. The straps 24 are secured to the attachment devices 14 disposed along the longitudinal sides of the platform 13, straps 24 lying between adjacent loops 23 being attached to a common attachment device 14. The harness 22 also comprises two longitudinal loops 25 which pass longitudinally over the bag 15 and are attached to the attachment devices 14 at the front and rear sides of the platform 13.

The harness is made from polyester webbing about 50mm wide and where it joins other parts of the harness the parts are united by sewing. The loops 23 have been described previously and here it should be explained that the portion of loops 23 between the two longitudinal loops 25 takes the greatest strain. It has been found that it is best if this section of the harness has a breaking strain greater than the remainder of the loop. In practice, we have found that the remainder of the loop 23 can have a breaking strain of greater than or equal to 6 tonnes preferably 7 tonnes, whereas the portion of each loop 23 between the two loops 25 has a breaking strain of greater than or equal to 12 tonnes, preferably 14 tonnes. The straps 24, which can conveniently be referred to as the A-bands also should have a minimum strength of 6 tonnes, preferably 7 tonnes.Comparatively the attachment points 14 should be similarly strong. It will be noted that on each side of the vehicle each loop 23 has an A-band which extends forwardly to an attachment point on the vehicle and an A-band which extends rearwardly to a different attachment point on the vehicle. This particular means for holding the ends encircling loops 23 gives a particularly firm support for the bag on the vehicle. It will be noted that longitudinal loops 25 extend completely around the vehicle. At the front and at the back of the vehicle straps 25a extend from the bands 25 to the vehicle support.

Referring now to fig. 2 there is shown an embodiment which is generally similar to that shown in Fig. 1 and described above. Corresponding parts are identified by corresponding reference numberals in the two figures. In the embodiment of Fig. 2 each strap 24 is attached to a respective attachment device 14.

This arrangement being particularly advantageous for larger bag sizes and greater longitudinal spacing of the loops 23. In addition in this embodiment additional end straps 26 are provided, being disposed "diagonally" across the corners of the bag 15 to give additional security. The straps 26 are attached to the attachment devices 14 to which the straps 24 were attached.

By means of the invention a transport vehicle may carry several bags 15 each for use with one specific liquid. In consequence no one container is required for use with differing liquids which should not be mixed together and the need for specialised cleaning between consecutive journeys is avoided.

Each bag 15 can be cleaned when required as a routine servicing matter. The bags 15 being constructed of two flat sheets of material joined along their edges are readily rolled up for storage purposes, but form a "pillow-shaped" container when filled with liquid. An advantage of storage of the bags 15 in a rolled up condition is that substantially all liquid and air are expelled from the bag as it is rolled, thereby reducing the tendency for any liquid left in the bag to deteriorate and become harmful or dangerous. This is particularly advantageous in the case of transportation of industrial latex the residue of which in a container would set in atmospheric conditions unless the container were to be carefully cleaned after discharge of each consignment. With a bag 15 in a rolled up configuration such setting is precluded, thereby avoiding the need for such frequent cleaning. A particular advantage of the present invention lies in the suitability of the vehicle 10 to transport one liquid from one location to another and to bring a different liquid, or even dry goods or a container on the load platform 13 on the return journey, without any cleaning being required at the other location. A further advantage lies in the fact that the bag 15 and harness 22 is considerably lighter in weight than steel containers of similar capacity so that a greater payload, e.g. an extra 2000 to 2500 kg can be carried on any particular vehicle 10 than would be the case with a conventional tanker vehicle of Suitable materials for the bag 15 are polyurethane coated, butyl, nitrile, green nitrile, blue butyl, nylon coated, platilon or green polyvinyl flouride (p.v.f.) nitrile rubbers, although other materials may be suitable. Also other constructions of bag may be used if desired and other harness configurations. Although the invention has been described in relation to a road-going vehicle the invention is equally applicable to a rail vehicle.

Claims

1. A transport container for the transportation of liquids in bulk comprising a bag, of liquid impervious flexible material, having closable port means whereby a liquid may be introduced into or discharged from it and being shaped so as to be capable of being formed into a small package when empty.

2. A transport container as claimed in claim 1, wherein the bag is shaped to lie flat when empty to enable it to be rolled into a small-volume package.

3. A transport container as claimed in claim 1, wherein the bag is shaped to that, when empty it can be folded to form a small volume package.

4. A vehicle for the transportation of liquids comprising a support and a transport container mounted thereon, said transport container comprising a bag, of liquid impervious flexible material, having closable port means whereby a liquid may be introduced into or discharged from it, and being shaped so as to be capable of being formed into a small package when empty.

5. A transport container as claimed in claim 1, 2 or 3, wherein the bag is of a rubber and/or plastics material.

6. A transport container as claimed in any of claims 1 to 3 wherein the bag consists of a pair of rectangular sheets of material which overlie each other and are joined to each other along their corresponding edges.

7. A transport container as claimed in claim 5, wherein the bag is made from a number of elongate strips of material which have been arranged side-by-side, seamed to form a hollow cylinder and then seamed along their mutual ends.

8. A transport container as claimed in claim 7, wherein from six to eight strips can be used.

9. A transport contaiie= as claiicf in any of claims 1 to 8 wherein at two corners of the container drain valves are mounted.

10. A transport vehicle as claimed in claim 4, and comprising securing means adapted to secure said container to the vehicle support.

11. A transport vehicle as claimed in claim 10, wherein the securing means comprises a harness.

12. A transport vehicle as claimed in claim 11, wherein the harness comprises a plurality of loops adapted to pass around said bag and a plurality of straps attached to said loops.

13. A transport vehicle as claimed in claim 12 wherein the straps are a relatively tight fit on the bag so that when the bag is filled the material of the bag between adjacent straps extends outwardly from the strap positions, each strap defining an inwardly directed ridge within the bag.

14. A transport vehicle as claimed in claim 12 or 13, wherein each loop has two or more straps attached thereto on each side and extending to the support on that side.

15. A transport vehicle as claimed in claim 14, wherein one strap of the pair extends forwardly and downwardly from its attachment point on the loop and the other of the pair extends rearwardly and outwardly from its attachment point on the loop.

16. A transport vehicle as claimed in any of claims 12 to 14, wherein two or more longitudinally-extending loops are provided to extend lengthwise of the bag, each loop having at each end of its upper run, a downwardly extending strap which connects with the support.

17. A transport vehicle as claimed in claim 16, wherein the longitudinally-extending loops and the transversely extending loops are connected together where they cross.

18. A transport vehicle as claimed in claim 17, wherein portions of the transverse loops between such interconnection points are of greater breaking strain than the remainder of the transverse loops.

19. A transport vehicle as claimed in claim 18, and having a bag which is 12 metres in length, there being six or more transverse loops arranged along the length of the bag.

20. A transport vehicle as claimed in any of claims 12 to 14 wherein the said support is a load platform and attachment means for said straps are provided on said load platform.

21. A transport vehicle as claimed in claim 20 wherein said load platform is rectangular and said attachment means are provided adjacent the sides and ends of said platform.

22. A transport vehicle as claimed in claim 4 or any claim dependent therefrom and being a road-going vehicle.

23. A transport vehicle as claimed in claim 22 or any claim dependent therefrom and being a rail, sea or air going vehicle.

24. A transport vehicle as claimed in claim 18, wherein the breaking strain of the central portion of the body loops is ; 6 tonnes and the breaking strain of the remainder of the loops is W 12 tonnes.

25. A transport vehicle as claimed in any of claims 9 to 24 wherein additional cross straps are provided at each end of the bag.

26. A transport vehicle as claimed in any of claims 1, 2, 3, 5 or 6 and provided with a pressure relief valve adapted to open upon a set maximum safe internal bag pressure being reached to reduce the chance of a road accident causing rupture of the bag and total loss of contents.

27. A transport vehicle substantially as hereinbefore described with reference to the accompanying drawings.

28. A transport vehicle substantially as hereinbefore described and being a rail, sea, or air going vehicle.