GB2076753A

GB2076753A - Tanks for Road or Rail Vehicles

Info

Publication number: GB2076753A
Application number: GB8116791A
Authority: GB
Original assignee: Alusuisse Holdings AG; Schweizerische Aluminium AG
Current assignee: Alcan Holdings Switzerland AG
Priority date: 1980-06-03
Filing date: 1981-06-02
Publication date: 1981-12-09
Also published as: DK223681A; GB2076753B; NO811838L; DK153754C; DK153754B; IT1136884B; CH646104A5; IT8121990A0; ZA813378B; SE8103424L; SE435047B

Abstract

Two pairs of longitudinal bearers 28 and 30 constitute components of the tank shell 20. These bearers can be manufactured in a simple manner in an extruding operation. Each pair of bearers 28, 30 is connected to and supported by a respective single longitudinal bearer 32. <IMAGE>

Description

SPECIFICATION Tanks for Road or Rail Vehicles The invention relates to tanks wherein at least the lower zone of the tank shell is constituted of extruded metal sections, arranged in the longitudinal direction, and securely connected together by welding, while the remaining part of the tank shell is constituted by a sheet metal casing. Examples have been published in U.S.

Patent Specification No. 3,187,425.

Tanks are used on semi-trailers with motordriven articulated power units, on trailers for lorries, and on lorries themselves. Additionally such tanks are used on rail vehicles.

The tanks can be made circular, oval, elliptical, or box-shaped in cross section.

Under existing legal regulations in, for example, the German Federal Republic, tanks serving for mineral oil transport are permitted up to a capacity of 40,000 litres. It is of great importance to manufacture such large tanks in a light-weight manner; saving of weight and a corresponding gain in usable load up to nearly 2 tonnes are attainable. Moreover consideration should be given to the fact that, for road traffic, box tanks have become widespread. This is probably to be attributed principally to the lower-lying centre of gravity, in comparison with circular tanks of equal length and equal volume, by which the running properties are improved in a notable manner.

In the interior of the tank there are arranged a plurality of dividing or baffle walls for strengthening and for sub-divfding the latter, which serve firstly for strengthening the tank structure and additionally also for improving the running behaviour of the vehicle.

Box tanks are relatively widely overhanging at each side. In many cases this necessitates strengthening by the arrangement of brackets on the lower strap sections or sectional sub-frames, or by provision of internal reinforcements, for example additional dividing and/or baffle walls.

Having regard to the different loadings arising during running operation, which for example subject the entire tank to torsion, and subject individual parts of it-corresponding to the current running situation-to tension, pressure, bending or stretching, while individual kinds of these loadings at particular portions of the tank can also interact simultaneously, a very great stiffness of the tank is of outstanding importance.

Naturally also, having regard to security against occurrence of cracks, permitting leakage losses, very good, durable, welded connections between the individual parts of the tank are necessary.

The tanks of the kind described above have in many cases, generally at one end, a special compartment for filling, and emptying devices.

Such a compartment may also have relatively long hoses for the filling and emptying of the tank, which take up considerable space.

In many cases of use, for example in the transport of gases, excess pressure may be produced in the tank. The weld seams of the tank have to withstand this excess pressure at the points of connection between the casing and the metal sections or between the individual sections.

The tank constructions known hitherto for road or rail vehicles have various disadvantages attached to them, which relate to the form of tank construction and also to the durability of the welded connections under extremely high internal pressures.

Underlying the present invention there is now the objective, to provide a self-supporting lightweight tank construction for road or rail vehicles, which is usable in many ways, that is to say can serve both for the transport of liquid or gaseous media and also for that of pulverulent or granular material.

The tank can be made circular, oval, elliptical or box-shaped in cross section.

According to the invention this objective is solved in a tank wherein at least the lower zone of the tank shell is constituted of extruded metal sections, arranged in the longitudinal direction, and securely connected together by welding, while the remaining part of the tank shell is constituted by a sheet metal casing, the tank being characterised by two pairs of longitudinal bearers constituting parts of the tank shell, one pair on each side of a longitudinal centre line of the tank, the bearers of each pair being supported together by a respective single longitudinal bearer and being connected with the latter by welding.

Further features which are preferred, but not essential, can be understood from the following description, with reference to the accompanying drawings.

The drawings show three examples of use of the invention as well as examples of embodiments of the invention. The drawings are diagrammatic, and are: Figure 1 is a side view of an articulated power unit with a tank semi-trailer; Figure 2 is a side view of a motor driven tank vehicle, together with a tank trailer; Figure 3 a cross section through a tank which in the plane of section is box-shaped, from which can be seen particularly the arrangement and shape of longitudinal bearers of a tank shell according to a first embodiment; Figure 4 a perspective view of the lower zone of a tank shell which has been sectioned on the line IV-lV in Figures 1 and 2; Figure 5 a cross section through a welded connection of an outer and an inner longitudinal bearer at the place indicated in Figure 3 with a circle "Z" in broken line, according to a second embodiment;; Figure 6 a cross section through a welded connection of two inner longitudinal bearers at the place indicated in Figure 3 with a circle "Y" in broken line, according to a third embodiment; Figure 7 a cross section through a welded connection between an outer longitudinal bearer and the tank casing at a point indicated in Figure 3 by a circle "X" in broken line, according to a fourth embodiment; Figure 8 a cross section through a welded connection of two inner longitudinal bearers at the point indicated in Figure 3 with a circle "Y" in broken line, according to a fifth embodiment; Figure 9 a cross section through the lower zone of a tank shell of a tank trailer in the zone of the fifth wheel on the line IX-IX in Figure 2; Figure 10 a partial view from below of the lower zone of the tank shell of a tank trailer in the zone of the fifth wheel; and Figure 11 a perspective view of the lower zone of a tank shell of a tank semi-trailer for an articulated power unit, sectioned on the line Xl- Xl in Figure 1.

From Figures 1 and 2 are to be seen exampies of uses of the tank construction 10 according to the invention in a tank semi-trailer 12 with an articulated power unit 14, on a motor driven tank vehicle 1 6, as well as on a tank trailer 18 for such a motor driven tank vehicle 1 6. The tank construction can also be used on rail vehicles in a manner not shown, if this is desired.

The tank construction 10 shown in Figures 3 to 11 shows as regards shape a so-called box tank.

With the help of the invention however, tanks which are oval or cylindrical in cross section can also be manufactured. The tank construction 10 has, as components of the lower zone 20 of the tank shell, longitudinal bearers 28 and 30 of light metal arranged in pairs, connected together by weld seams 22, 24, and 26. These bearers are manufactured in an extrusion process. Each pair 28, 30 together are supported by a single longitudinal bearer 32, likewise manufactured of light metal in an extrusion process, and connected with bearers 28, 30 by weld seams 34 and 36.

The two outer longitudinal bearers 28 preferably have the same shape and can therefore, in a manner not shown in more detail, be made with the help of one and the same extrusion tool.

Likewise the two inner bearers 30 are of similar shape. The two outer longitudinal bearers 28 are provided with an obliquely inclined wall 38 extending in the installed condition over the total length of the bearers, onto which joins the tank casing 40 of light metal, generally over 4 mm thick, which is connected over its entire length, by a weld seam 44, with an upper edge 42 terminating the obliquely inclined wall 38.

The outer longitudinal bearers 28 are made as hollow sections and have on their side towards the central longitudinal axis of the tank a wall 46 which is preferably arranged vertical in the installed position. Opposite this wall 46 there is a flange 48 on the inner longitudinal bearer 30, preferably arranged verticai. On the wall 46 of the longitudinal bearer 28 as well as on the flange 48 there is provided a longitudinally extending projection 50, 52 respectively. These abut on two upper edges, 54, 56 respectively, of the associated longitudinal bearer 32. Each bearer 32 preferably has a cross section which is of approximately inverted-U shape.

In the assembled conditions, each pair of outer and inner longitudinal bearers 28, 30 is welded to the bearer 32 by weld seams 34 and 36, while the preferably vertically arranged wall 58 of the longitudinal bearer 32 joins onto the obliquely inclined wall 38 of the outer longitudinal bearer 28.

The outer and inner longitudinal bearers 28 and 30, as well as the longitudinal bearer 32 supporting them, are shaped in such a way that in the assembled condition a tubular-shaped compartment 62 is formed between them. This principally serves for accommodation of components of equipment, not shown, such as hoses and other appliances, for use in association with the tank. The outer and inner bearers 28 and 30 are provided with ribs 64 extending in the longitudinal direction, for strengthening the housing. On the inner longitudinal bearers 30, the ribs 64 are made T-shaped at their lower ends 66, and by them are welded onto transverse bearers 68 (Figure 4). Furthermore plates 70 are connected with the transverse bearers 68 and with the bearers 32.These plates 70 can be connected with mounting brackets of the motor vehicle, or on them can be fitted axle brackets of a trailer or semi-trailer.

According to the first embodiment, described above and shown in Figures 3 and 4, the outer and inner longitudinal bearers 28 and 30 abut against one another and, as already mentioned, are fixed together by the weld seams 22, 24 and 26. In addition, the longitudinal bearers 32 carrying the outer and inner longitudinal bearers 28 and 30 are connected through two further weld seams 34 and 36, so that the forces introduced from the vehicle frame during running operation are advantageously distributed over all the weld seams 34 and 36 as well as 22, 24 and 26.

According to the second, third and fourth embodiments shown in Figures 5, 6 and 7, the longitudinal bearers 28 and 30, in the neighbourhood of their welded connection points, have particular cross sections, which generally come into use in the so-called circular tanks, not shown here, especially if these are subjected to high internal pressures.

Figure 5 shows that the outer longitudinal bearer 28 has a groove 74 extending over its entire length and the inner longitudinal bearer 30 has a tongue 76 extending over the entire length of the latter. In the assembled and connected condition of the two longitudinal bearers, the tongue 76 lies in the groove 74.

Figure 6 shows that the two inner longitudinal bearers 30 in the neighbourhood of the weld seam 24 each have a groove 78, preferably semicircular, which in the assembled and connected condition of the tank shell are both opposite one another A tightly fitting circular bar 80 is introduced into the grooves This principally serves for centralisation of the two components during assembly of the latter.

Figure 7 shows a longitudinal groove 82 in the outer edge of the outer longitudinal bearer 28, in which one edge of the tank casing 40 is inserted.

The casing 40 is secured by weld seams 84 and/or 86 arranged on one or both sides of the casing 40.

Figure 8 shows an alternative cross sectional shape of two inner longitudinal bearers 30 in the neighbourhood of the weld seam 24, which permits good illumination by X-rays of the weld connection on checking for defecting places.

Figures 9 and 10 show the fixing of a fifth wheel 88 onto the tank shell of the tank trailer 18 shown in Figure 2.

Figure 11 shows the fixing of an articulation plate 90 on articulated semi-trailer 12 onto both the longitudinal bearers 32 as well as onto the transverse bearers 68 of the tank shell 20. The articulation plate 90 carries a king pin 92, which can be brought into engagement with a coupling on the articulated power unit, not shown in more detail.

The invention is not restricted to the shown embodiments. For example yet another cross sectional shape of the longitudinal bearers of the tank shell is conceivable within the scope of the invention, without departing from the actual inventive concept. For example between the tank shell 20 and the plates 70 there could also be arranged, in a known manner not shown, elastic or yielding damping elements, if these are desired.

The tank construction according to the invention makes a high contribution to safety against leakage, as a consequence of the relatively great strength of the tank itself, extending to the outer sides of the tank. In collisions it is of particular advantage that there are no brackets, such as have been used hitherto.

Such brackets are often a cause of damage; for example in a glancing collision significant damage to the tank casing can be brought about.

The tank construction can be manufactured at advantageous cost. Moreover it requires relatively small interior reinforcements, such as dividing or baffle walls.

Claims

1. A tank for a road or rail vehicle, wherein at least the lower zone of the tank shell is constituted of extruded metal sections, arranged in the longitudinal direction, and securely connected together by welding, while the remaining part of the tank shell is constituted by a sheet metal casing, characterised by two pairs of longitudinal bearers constituting parts of the tank shell, one pair on each side of a longitudinal centre line of the tank, the bearers of each pair being supported together by a respective single longitudinal bearer and being connected with the latter by welding.

2. A tank according to claim 1, characterised in that, between the bearers of a pair and the longitudinal bearer supporting the latter, a longitudinal compartment is provided for the housing or storage of equipment for use in association with the tank.

3. A tank according to claim 1 or claim 2, characterised in that the two outer longitudinal bearers each have an obliquely inclined wall extending over the total length of the respective bearer.

4. A tank according to claim 3, characterised in that the casing of the tank joins onto the obliquely inclined walls of the outer longitudinal bearers.

5. A tank according to claim 3 or claim 4, characterised in that a wall of each supporting longitudinal bearer joins onto the obliquely inclined wall of the respective outer longitudinal bearer.

6. A tank according to any of claims 1 to 5, characterised in that the longitudinal bearers are connected by welding with transverse bearers.

7. A tank according to claim 6, characterised in that the supporting longitudinal bearers and the transverse bearers are all connected together by plates.

8. A tank according to claim 6, characterised in that the supporting longitudinal bearers and the transverse bearers are all securely connected together by a plate carrying a king pin.

9. A tank according to any of claims 1 to 8, characterised in that the two outer longitudinal bearers are similarly profiled to each other, and the inner longitudinal bearers are similarly profiled to each other.

10. A tank according to claim 9, characterised in that the longitudinal bearers of each pair are connected together by tongue and groove and also by weld seams.

11. A tank according to claim 9, characterised in that the outer longitudinal bearers are each provided with a groove running in the longitudinal direction of the tank, in which a respective edge of the tank casing is inserted, and welded with a help of weld seams arranged or one or both sides of the casing.

12. A tank according to claim 9, characterised in that the two inner longitudinal bearers in the neighbourhood of the centre line each have a groove, and the grooves lie opposite one another, and a tightly fitting bar is inserted in the grooves.

1 3. A tank according to claim 1, substantially as described with reference to Figure 3, Figure 4, Figures 9 and 10, or Figure 11 of the accompanying drawings.