A TRANSPORT TANK, PARTICULARLY FOR DANGEROUS SUBSTANCES

Abstract: Dangerous substances are normally transported by tank lorries which are subjected to heavy security demands, whereby the transports become not only dangerous, but also expensive. Hereby the receivers are prompted to purchase the substances in large quantities, which in their turn involve an increased environmental risk with the users. According to the invention there is provided a ''tank container'' (2) shaped as movable security tank (4) having a volume of only some 5000 l and being rigidly connected with a carrier frame (16), which is provided with standard container corner fittings (24) and passages for receiving lift forks, i.e. the tank unit is optimized for safe transportation and handling, and it is well suited to be transported in the safest manner, viz. by ship or railway, though of course also by truck. The receivers may then purchase the substances in smaller quantities, and they can even utilize the tank units as storage tanks, whereby fixed tank installations can be cut down.

Description: A transport tank, particularly for dangerous substances. The present invention relates to a transport tank, having a volume substantially exceeding 1000 1, in particular for transport of dangerous liquids, pastes and granulates. Lately the severe risks involved in the transport of many kinds of goods, in particular in the transport by road of liquids in tank lorries, have been recog¬ nized, and consequently, the security requirements on tank lorries approved for transport of dangerous liquid substances are very heavy. This implies, taking the rather high costs of transport into consideration, a liability to purchase the mentioned dangerous substances in large amounts, implying larger local risks when keep¬ ing undue large stocks of the often very toxious, environmental deleterious substances. From point of view of safety, it is preferable to transport hazardous sub¬ stances, liquids or solids by rail or ship, but the costs of associated prescribed safety devices result even here in rather large transport containers, i.e. still an increased local economical and environmental risk. The purpose of the invention is to provide a trans¬ port container or tank of the type referred to above and allowing for a more economical transport of hazardous substances. The transport containers or tank according to the invention has specific features as indicated in the characterizing part of claim 1. By designing the tank as a relatively small tank unit built up of a sufficiently stiffened 'security tank with a carrier frame, fitted for habitual handling when loading, and for fastening to the means of transport, the tank may serve as a sepa¬ rate, mobile unit or container, with largely extended possibilities compared with conventional larger tanks firmly connected to the means of transport. Thus the primary transport by rail or ship can be increased, and the more dangerous transport by lorry be reduced to a secondary transport from the goods station or port to the recipient, and the result is thus a more safe trans¬ port. But even here, very heavy requirements of safety should be satisfied. Accordingly the users do not need to buy the dan¬ gerous substances in the above mentioned undue large amounts, the advantages being both economical and relat¬ ing to risks of local environmental accidents. Further, the transport unit may serve as a storage tank until the contents have been used, thus saving costs of stationary tank installations, and in addition by the use of parti¬ cularly safe tank units, which further can be returned to the transport system after use. A specific tank unit can thus be returned to the consignor and refilled with an identical product, or used for other purposes after cleaning, preferably in an extensively used standardized 'tank container system'. As a specific feasibility, a separate lining bag can be inserted in the tank, which is thus cleaned by taking out the bag, and thereafter ready for inserting a new bag for the following filling. The upper opening of the bag may act as tightening along the edge of the cover of the upper access opening of the tank. The bag can be shaped to fit the tank, and so that it easily can be taken out from the upper access opening and through this opening. Another bag can be inserted through the opening and connected to the edge of the opening and brought into position as a lining by means of a vacuum, applied through a pipe branch on the wall or bottom of the tank. If the tank is provided with a suction well at the bot¬ tom, the bag should be shaped to fit thereto. A roller-supported carrier frame or wheel units for mounting under the bottom frame of the tank are possible accessories. To avoid transportation of such acces¬ sories, they may be located where the tank units are used. The tank units may appropriately be designed so as to fit into habitual ISO-containers, whereby - in spe¬ cial situations - they can be forwarded in such con¬ tainers and also - more generally - be returned or dis¬ patched together with empty ISO containers without tak¬ ing up additional space. In the following the invention is explained in more detail with reference to the drawing, in which:- Fig. 1 is a perspective view of a tank unit accord¬ ing to the invention, Fig. 2 is a perspective view of another embodiment, Fig. 3 is a side view of a railway truck loaded with tank units according to Fig. 1, Fig. 4 is a perspective view of a modified, pre¬ ferred embodiment, and Fig. 5 is a sectional view of the upper part of the very tank of the tank unit. The tank unit 2 as shown in Fig. 1 comprises an upstanding cylindrical tank 4 built up with a genuinely cylindrical central part 6 and two convex ends 8 and 10, the top end with a cover 12 on an access opening to the tank. The tank 4 is supported on a carrier frame 16 by radial steel plate supports 18, welded to the carrier frame 16 and to the tank 4, the supports reaching from beneath the bottom end 10 and up along the central part 6. At the top, the supports are provided with eyes 20 for handling the tank unit in straps by crane. The carrier frame 16 consists of four flat, hollow, rectangular profiles 22, intersecting at the corners, partly by means of extensions 24 welded to the profiles. Both pairs of profiles 22 are open at the ends allowing for insertion of the forks of a usual fork-lift truck. The external part of the corners of the carrier frame includes conventional container corner fittings 24 with lower holes not shown for insertion of container locks of the twist-lock type enabling securing of the tank unit to a suitable carrier surface of the means of transport. Generally, the tank unit can be handled by ordinary equipment on container terminals. Fig. 2 shows an embodiment, where the supports 18 are somewhat enlarged, as they are extended over the top end 8 of the tank 4, resulting in an increased struc¬ tural stability. Fig. 3 shows how five tank units 26 can be placed on a railway truck, safely secured to the truck by con¬ tainer locks. Fig. 4 shows a preferred embodiment where vertical corner posts 28 are mounted on the corners of the car¬ rier frame. The upper ends of the posts are connected to a top frame 30 in level with the top of the tank 4, or, more precisely, with the cover 12, which, for safety's sake should not extend above the frame 30. Container corner fittings 32 are placed at the upper ends of the posts 28, i.e. at the corners of the top frame 30, enabling stacking of the tank units 2, locked to each other. In the embodiment shown in Fig. 4 the lower carrier frame is simplified as it is built up with only two of the above mentioned hollow profiles 34, being parallel and opposite to each other and of large cross sectional width to allow for use of forks spaced at various non-standard distances. Further, it is shown how the supports 18 are fastened to the tank exclusively at the central, cylindrical part 6, resulting in a simplified design of the supports. As indicated on the figure, the supports do not even have to extend to the bottom frame 16 as fastening to the posts 28 ensures support of the tank 4 as well as or even better than in the construc¬ tions shown in the Figures 1 and 2. By using the two profiles 34 for the bottom carrier frame 16, it is accepted that handling by fork-truck cannot take place from all sides, but only from two opposite sides, which, by experience, is satisfactory. This leads, however, to a considerably simplified frame structure where the profiles 34, although not directly connected to each other, form a stabilized structure, i.e. by their fastening to the tank 4 through the posts 28 and the supports 18. It has been emphasized above that the volume is substantially in excess of 1000 1, although the volume, according to the invention, is preferably considerably less than the volume of the otherwise used tanks incor¬ porated in trucks, the preferred volume being 5000 1. This still exceeds 1000 1 essentially - the limit refers to already known pallet-mounted containers, cf. e.g. US-A-4,173,288, which, with a volume of around 1000 1, are intended for internal use, and without any quali¬ fications relating to safe external transport, neither regional nor international. It should finally be mentioned that a lining bag 36 can be inserted in the tank 4 as shown in Fig. 5, cf. also the description above. The bag may, at its upper opening, form sealing to the upper tank cover 12. The tank 4 may be provided with a lower draining branch, or a suction well enabling draining of the con¬ tents by a suction pipe introduced into the tank from above. In case the tank is furnished with a suction well, the lining bag should, of course, be shaped with a corresponding depression.

Claims: C L A I M S : 1. A transport tank with a volume substantially exceeding 1000 1, in particular for transport of dan¬ gerous liquids and granulates, characterized in being built up as a separate, detachable transport unit com¬ prising a pressure-resisting upright tank of the type having a cylindrical control part and convex top and bottom ends, which tank is mounted on and rigidly fastened to a horizontal bottom frame, provided with passages for receiving lift forks, the tank, the volume of which is preferably some 5000 1, being fastened to the bottom frame by vertical support plates upstanding from the corners of the bottom frame and extending in¬ wards for fastening to the exterior of the tank, said bottom frame being provided with or made as container corner fittings at the corners, so that the tank unit can be secured to a truck body or other carrier struc¬ tures. 2. A transport tank according to claim 1, charac¬ terized in that the volume of the tank is 4000-8000 1. 3. A transport tank according to claim 1, charac¬ terized in that it is designed to be fit in an ISO-con¬ tainer. 4. A transport tank according to claim 1, charac¬ terized in that it is provided with a separate, internal lining in form of a shaped, detachable lining bag of a resistant material such as Neoprene, the upper part of the bag being designed to form a packing member for mounting along the edge of an upper access opening of the tank, which opening is provided with a cover. 5. A transport tank according to claim 1, charac¬ terized in that the bottom frame consists of two paral¬ lel channel profiles spaced from each other, and not directly interconnected, connection being established through their connection to the tank. 6. A transport tank according to claim 1, charac¬ terized in that corner posts are fastened to the corners of the bottom frame, the upper ends of the posts being connected through a horizontal top frame being level with the top of the tank or its upper cover, and in that the corners of the top frame are provided with container corner fittings allowing locked stacking of several transport tanks.

Inventors: BERG LEIF, BERG, LEIF
Applicants: COMMERCIAL LEASING A S, COMMERCIAL LEASING A/S
Application year: 1989
Main classification: B65D90
IPC codes: B65D88