ZA200202558B - Tank for the transport of liquids. - Google Patents

Abstract

The container for transporting liquids comprises a tank with body (10) and end plates (11, 12) made form thin steel sheet or plastic. This is transported inside a conventional container and has spacers (13) consisting of foam material, wood or air cushions along its base.

Description

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Transport device for liquids

The invention relates to a transport device for liquids. ) Bulk transports of liquids are usually implemented in tank ) containers or flexible tanks. It is known that the main advantage of a so-called flexitank over a tank container consists in that it offers considerable cost advantages in almost all applications. However, it 1s disadvantageous that tanks made of rubber or plastic are always relatively prone to leakage and therefore are very sensitive. They require a considerable effort regarding handling, care, inspection and permanent maintenance. The considerable risk associated therewith is always latent disregarding all care, simply because the tanks pass through many hands and there will always be people in this chain not having the capability to handle such complex systems. In view of this difficulty, all suppliers of flexitanks try hard to offer a service as qualified as possible.

However, what should a technically advanced transport tank system be like in order to be able to avoid the mentioned

B risk factors and disadvantages, without being forced to dispense with cost advantages? And not only this:

Furthermore, additional advantages are expected from an advanced system as well, in order to be able to remain competitive in the long term under the permanently rising pressure on prices.

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The answer to the raised question is a newly developed "steel inlay tank system" or "sheet inlay tank system" or also graduated/composed "stagger inlay tank system”. oo The SIT system is based on the following considerations:

The principle of the "inlay" analogous to the flexitank shall be stuck to. Thereby, the known advantages of a stagger system, i. e. of a "retrofitable tank in standard tank”, are maintained. Taking this principle recognised as economically optimal as given, considerations leading further must be directed to alternative materials and construction.

Sheet metal is the construction material used most frequently and is in this much cheaper than, for example, coated fabric, but, above all, sheet metal as the "classical" material with superior strength values is absolutely calculable. Tanks made of coated sheet steel, for example, Niro, or coated aluminium alloy are regarding their usability substantially more versatile and less problematic than tanks made of coated fabric. Furthermore, refined and up-to-date sheet metal coating methods are available today. Above that, it should be clear that hardly any leakage and scrub problems will occur with tank inlets made of sheet metal.

However, for reasons of technical handling it would be hardly sensible to completely assemble the inlay tanks already in the production operation. The transport costs of the empty packages to the sites of use often located far away would simply be too high. Thereby, the system would be ) unprofitable from the beginning such that a further thought must be considered, that 1s the conception as a kit.

In order to make the matter complete, a further condition must be satisfied: the system must be such lightweight and simple that an assembly on-site can be carried out under minimal effort and that the costs of transport are bearably low as well. This in turn is possible due to the special construction of the SIT system. Last but not least, a new system can only succeed in the market, if a large potential of demand can be satisfied hereby, and that with regard to the number of units as well as the requirements. This in turn arises as a side effect from the consequent use of the kit concept in mechanical series production, however, without disadvantageously restricting the variation range of the system: the possibility exists to combine different sheet materials with different coating techniques.

The SIT system substantially consists of a spirally welded, tubular jacket and two almost identical front plates made j of deep-drawn sheet metal. The individual parts are assembled to the tank inlay and inserted into the standard container shortly before delivery to the forwarder.

Thereafter, the system is ready to the loaded and can be transferred to the forwarder. Of course, 1t 1s also possible or sensible in some cases, to let the forwarder carry out the assembly of the tank inlays himself. After some practice, the whole assembly will take two men about to 15 minutes.

A package complementing the kit contains wedge pieces made oo of polystyrene or air-cushions, respectively. The wedge pieces are required as lining pieces, in order to support the tank inlay in the transfer region from the bottom to the side wall during the loading process and must be inserted into the container during the assembly. The front plate is smooth, the back plate has three connections: one connection in the lower area for the filling or emptying of the tank, a central connection for cleaning of the tank (for the spray lance) and one connection in the top area for deaeration/aeration during the loading/discharging of the tank.

The key element of the construction is the closure "jacket pipe/front plate”. In this respect there are generally two different construction possibilities, wherein it is to be clarified, whether the closure may be made inseparable (irreversible) or must be designed separable (reversible).

In the end, this is a question purely relating to technical handling. An inseparable closure can be mounted relatively easy, - for example by sticking or soldering. It should be possible for most applications, i. e. for example for all single-use applications and several multiple-use applications, in which the tank can be cleaned without any problem. Separable closures require more effort even as quick-release closure, only in that the assembly and disassembly operations have to be repeated in every single application. The substantial advantage of separable closures consists in that disassembled empty packages can be transported at considerably lower costs, above all, of course, over long distances. It is required in this context to weigh advantages and disadvantages regarding technical handling against each other.

There are also some special applications with special directions, for which proven additional equipment can be made available. Thus there are, for example, additional drip trays for transports with especially high safety directions and very low cost and easily incorporable heater bands common in the trade for cases, in which the product must be transported in a heated condition. Of course, insulating blankets tailored to the system can be provided or supplied, respectively.

The system can be used almost unlimited, and that for: - all foodstuff, mineral oil and lubricant products and almost all chemicals, - easily perishable foodstuff, such as milk, tomato puree, orange juice concentrates, fresh juices and j suchlike. For such transport tasks the SIT system can be aseptically adjusted, - products, which must be transported in a warm or hot state. For this, a heating system easily incorporated and common in the trade, if applicable combined with insulating blankets, is available,

- very viscous, poor flowing products such as printing ink, honey, and suchlike. - dangerous goods after examination and release. . The systems according to the invention are substantially cheaper than flexitanks or even tank containers; considerably safer to operate than any very good flexitank system, in fact as safe to operate as tank containers; offer an additional safety bonus.

They lie protected and, so to speak, safely embedded "like in the bosom of Abraham" in the actual container.

Due to the free spaces located in-between free crumple zones arise; can be assembled easily and safely: by two men in fifteen minutes; to be handled much easier than flexitanks; can also be emptied with the aid of compressed air; can be emptied completely without any problem.

Possible problems that nests can form as in the flexitank with residues up to 500 kg naturally do not occur; to be cleaned easily, and that mechanically;

do hardly require any maintenance; can be used without requirements regarding the quality of ) the standard container; } can be disposed of after use without any problem. Used tanks are simply exhausted and are then delivered to the metal recovery in form of flat crumpled packets; can be produced in large numbers at appropriate dates. The handling is organised such that all possible cases of need can be quickly covered; can be used in single~use as well as multiple-use trade. In the latter case, the tank inlays must be cleaned after every use with a spray lance.

The systems according to the invention are distributed and brought into trade through forwarding and shipping companies represented world-wide. They are stored in licensed depots as kits and are fitted into the standard container when delivered to the forwarder. Then the system oo can be filled similarly to a tank container. Systems used in single-use trade are scrapped after use. Multiple-use systems are cleaned in a licensed depot or directly after unloading at the discharger and are kept ready for the next use. A use for similar products of one product group is permitted, 1. e. that in tank inlays intended for foodstuff, only foodstuff and nothing else like chemicals may be transported in-between. However, 1t 1s also permitted to downgrade a foodstuff tank, for example from foodstuff to chemicals, but not vice versa. Respective indications are situated at the rear front plate of the tank inlay.

The following table values are based on the idealised . assumption of a circular lying cylinder. This was taken as a basis for the calculation of the cubages at first. The cross-section actually constructed thereafter corresponds to a flattened cylinder, approximately like a loaf of bread, whereby the height of the tanks is reduced and the width 1s extended up to the container width.

Capacity Applications Diameter Length Front ms m m plate 16 Concentrates 2.00 5.10 "A" 17 Intermediate 2.00 5.45 "A" size 18 Heavy, watery 2.00 5.80 "A" solutions 19 Intermediate 2.25 4,80 "B" size

Wine and watery 2.25 5.05 "B" solutions 21 Wine and watery 2.25 5.30 "B" solutions 22 Intermediate 2.25 5.55 "B" size _ 23 Oils and latex 2.25 5.80 "B" 24 Special size 2.30 5.80 "ce

It can be gathered from this table that - disregarding the special size - front plates are only required in two sizes, in order to cover the whole program. The lengths, disregarding the intermediate size "19 m*" - range between 5.05 and 5.80 m.

Characterising features of the present invention are the tank on the one hand and the mounting of this tank in the transport container on the other hand.

For the tank, a cylindrical or semi-cylindrical shape or . modified designs have proven to be worthwhile, wherein the optimum shape corresponds to that of a loaf. The tanks can be designed such that they can be inserted into each other, when they are to be transported in the empty condition. If tank halves longitudinally cross-divided are used, these can be designed slightly conical and can be inserted into each other.

The connection possibilities for the tank parts are seals in the most varied embodiments, which can be easily coped with viewed from the purely technical aspect. In the longitudinally cross-divided tank a central bulkhead with an inflatable seal is used, by which the two tank parts, if desired, can be sealed against each other and the sealing connection of the two tank segments towards the outside is implemented as well.

The invention will be explained below with reference to the ) drawing.

Fig. 1 shows a front elevation of an arched cylindrical tank in a container.

Fig. 2 shows a front view of a plurality of substantially cylindrical parts inserted into : each other of a device according to the oo invention.

Fig. 3 shows a longitudinal cross-section through a different embodiment of a tank according to the invention having anchoring rods located inside.

Fig. 4 shows a longitudinal cross-section through a different embodiment of a tank according to the invention having anchoring rods located outside.

Fig. 5 Shows, in an altered scale, the joint of two tank segments with a central bulkhead.

Fig. 6 shows a cross-sectional view through a tank according to the invention with ideal cross- sectional design.

Fig. 7 shows a longitudinal cross-sectional view ) through a tank according to the invention.

Fig. 1 shows a front elevation onto the tank 10, 11, 12, and that in an embodiment, in which the jacket 10 assumes a shape substantially corresponding to the interior of the container 20. 13 indicates filling pieces made of wood or plastic.

For security reasons, a drip tray could be additionally provided inside the container 20 such that in case of a ) leakage of the tank 10, 11, 12 the liquid leaking out cannot flow out of the interior of the container 20.

Likewise, an additional extendable closed sheet can be provided inside the tank 10, 11, 12 such that an increased safety can be achieved during the transport.

Fig. 2 shows empty jacket parts 10 pushed into each other, which can be transported in this manner inside of a transport container to a production site. The produced jacket parts are slightly deformed and are then pushed into each other such that the shown five jackets pushed into each other as a whole have roughly the length of one jacket taken on its own. On-site, the innermost of the jackets 10 is taken out first and is connected with the two front side parts to a tank 10, 11, 12.

Due to the cylindrical design of the jackets 10, these can be inserted into each other in that they are inwardly ) deformed at the lower area as shown in fig. 2. ]

The two anchoring rod constructions 40 of the figs. 3 and 4 represent two further variants of the tank 10 according to the invention.

The optimised cross-section geometry for the tank 10 is clearly illustrated in fig. 6, as the main field of application of thin-walled heavy-duty tank constructions is exactly designed according to this cross-sectional design. The deviation from the purely cylindrical form, which is ideal for the compressed gas cylinders, arises for ) liquid loads from the triangular shape of the hydrostatic . pressure curve. This loaf shape develops also during the . loading of the flexible tanks. Insofar an ideal shape for thin-walled membranes according to the scap film model is copied for half-rigid tanks (made of sheet metal) here.

They can also be referred to as a flattened cylinder resulting from the overlap of a rectangular vertical pressure curve with a triangular one.

The expansion of the application to two-part systems is shown in fig. 5. In this, it is necessary that the cups 10' and 10'' are designed conical such that they can be economically transported stacked into each other as empties {20 to 30 units in one container). The assembly is reduced from two levels to one level. In this, the anchoring rods and one seal are dropped. However, a central bulkhead 41 and 42 is added, which might seem to require more effort, but offers lots of advantages. It is substantial that a considerable dimensional stability is achieved by the cup oo shape and the central bulkhead, which is indispensable ) especially for thin-walled constructions. The dynamically effective closure and sealing mechanism 43 to 46 provides a high degree of functional safety, which is especially important in case of deformations on occurrence of an accident. The seal 43 and the closure 44-46 independently, so to say, always and immediately readjust. The rubber tube 43 is inflated and exhausted through an air valve at the outer perimeter of the central bulkhead 41 in medium height yo : in the semicircle of the roof section 10' or 10'', respectively. Therefore, the valve cannot rub on the container wall and is still accessible, when the tank is ) filled. - The cup shape with the illustrated closure mechanism may be preferred in the material variant made of stainless steel also especially for applications handling dangerous goods, wherein only the wall thickness must be increased.

Fig. 7 shows two assembled cup parts with central bulkhead, wherein the two interiors can be filled and loaded from a longitudinal side of the tank.

Claims (3)

1. Claims

   } 1. Device for the transport of liquids comprising a tank . ] fitting into the interior of a transport container used in R common trade, characterised in that the tank (10, 11, 12) is formed by a substantially cylindrical or half- cylindrical casing (10) made of thin plate of plastic, which terminates on both sides in an integrally formed end wall, and that mounting or distance elements (4, 13) made of foam material, wood or air cushions are provided in the bottom area, in the lower side area or in the lower corner areas of the container (20) for the tank (10, 11, 12) disposed in the interior of a container.
2. 2. Device according to claim 1, characterised by several tie rods (40) extending longitudinally of the tank (10), which are disposed inside or outside of the tank.
3. 3. Device according to one of the claims 1 or 2 characterised by a bulkhead (41, 42) dividing the tank (10', 10'') into two parts with an extendable annular i rubber diaphragm (43) arranged radially outside, which | | . tightly joins together the two tank parts (10', 10''").