EP0095476B1

EP0095476B1 - Wall element for a container such as a silo

Info

Publication number: EP0095476B1
Application number: EP19820903600
Authority: EP
Inventors: Sven-Erik Ahl; Lars-Bertil Nilsson
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-12-08
Filing date: 1982-12-07
Publication date: 1986-04-09
Also published as: DK354383D0; DK354383A; SE447405B; SE8107331L; DK163316C; EP0095476A1; DK163316B; DE3270502D1

Abstract

When a silo (26) is filled with slow-running material, this has a tendency to stick on the walls of the silo. This is avoided in accordance with the invention, by constructing wall elements (1) consisting of stackable units (2A and 2B) having a cross-section in the shape of a trapezium with the smaller (4 and 6) of the two parallel sides (4, 6 and 7) facing upwards.

Description

The present invention relates to a wall element for containers such as silos. Such containers consist of a surrounding wall and a bottom with an opening for removing the contents. Known containers have the drawback that, when filled with slow-running material, the material has a tendency to stick to the walls, which is not desirable. Another drawback with known containers is that it is difficult to make the surrounding walls sufficiently stable to withstand the pressure arising when the container is full and at the same time convenient to handle. By CH-A-495 485 is known a container with wall elements consisting of stackable units having a cross-section in the shape of a symmetrical trapezium with the smaller of the two parallel surfaces facing upwards. The wall elements are however difficult to handle as they are made of concrete.
The object of the present invention is to eliminate the drawbacks mentioned above, and this is achieved by using units which are stacked one on top of the other, where each unit is hollow by being built up by plates. The cross-section is preferably symmetrical. Considering a wall of units in the filling direction, it will be seen that at the transition from one unit to the next, there is a volume expansion resulting in expansion of the material flowing down. This volume expansion can be displaced slightly by providing each unit, at least on the inner side, with a downwardly directed, longitudinal tongue or flange so that an air-cushion is formed inside each tongue or flange.
The shape of the unit cross-section thus provides the silo with a stable wall.
Units stacked on top of each other are joined by securing plates arranged at the ends of the units.
Further characteristics of the present invention will be revealed in the following claims.
The present invention will be described more fully with reference to the accompanying seven drawings, in which

Figure 1 shows a cross-section through a wall element in accordance with the present invention,
Figure 2 shows two wall elements are joined together,
Figure 3 shows how walls elements can be joined for different silos, and
Figure 4 shows in part the bottom construction of a silo.
Figures 5 to 8 show another embodiment of the invention.

Figure 1 shows a wall element 1 consisting of two units 2A and 2B stacked, one on top of the other. The two units have a cross-section in the form of a trapezium said trapezium being symmetrical. Each trapezium consists of three bent, rectangular plates. Two of these three plates have L-shaped cross-section. One of these plates has a side section 3 and top section 4, and the other has a side section 5 and top section 6. These two plates are joined together at the bottom by a rectangular plate bent to give it a U-shaped cross-section. The central section of this plate is designated 7 and constitutes the bottom of the unit 2A. The bent parts of the plate, together with the lower ends of the side sections 3 and 5, form two longitudinal flanges or tongues 8 and 9. The unit 2B is constructed in exactly the same manner as the unit 2A. A first plate thus has a side section 10 and a top section 11. The second plate has a side section 12 and a top section 13 and the third plate has an intermediate section 14, forming the bottom of the unit. Together the three plates form two longitudinal flanges or tongues designated 15 and 16. The two units 2A and 2B are equal in length and their end surfaces are perpendicular to the longitudinal direction of the units. Each units is welded at its end to a connecting plate, one of which can be seen and is designated 17. The connecting plate has an intermediate section and two edges bent up, shown clearly in Figure 2. The two units 2A and 2B are welded or secured in any other suitable manner to the intermediate section. In the present case, a wall element comprises two connecting plates and two units. However, it should be evident that each wall element may comprise more than two units, in which case the connecting elements will be as long as the number of units is high.
Two wall elements which are to form a right- angle with each other may be joined in the manner shown in Figure 2. In this figure, the wall element 1 is shown with its connecting plate 17 which has two bent sections 18 and 19. The section 19 is in contact with the bent section of a connecting element 23 for a wall element 22 which is to be at right-angles to the wall element 1. The two adjacent, bent sections of the connecting elements 17 and 23 are joined together by a bolt joint 21. To ensure that the wall elements 1 and 22 assume a stable position, the bent section 18 of the connecting element 17 must be joined to the bent section of the connecting element 23. This is effected by means of a connecting plate 24, secured to the bent sections by means of bolt joints 20 and 25. The connecting element 24 may be eliminated if two more wall elements are to be joined to the two wall elements 1 and 22. Figure 3 shows how silos of varying width can be constructed with the aid of wall elements in accordance with the invention. In this figure several silos are combined to a single unit. However, it should be clear that the various silos 26-31 may also be constructed separately without being joined together.
Finally, Figure 4 shows how the bottom 32 of a silo can be arranged in a silo construction comprising wall elements in accordance with the present invention.
A silo in accordance with the present invention functions as follows. If the silo is filled from the top with a slow-running material, this will normally be able to run down one side section 3 since the side section is not to high. A suitable height has been found to be 435 mm. When the slow-running material reaches the lower edge or flange 8 of the unit 2A, the material is relinquished and continues down. Furthermore, the silo becomes wider at the transition from one unit to another in the filling direction, which facilitates the filling process. Naturally the flange 8 may be dispensed with, but the air-cushion formed inside it offers an advantage during filling and such a flange 8 is therefore to be preferred.
According to the invention, therefore, slow-running material is saved the necessity of flowing long distances. It need only flow a short distance before being caused to fall some way before starting to flow again.
As can be seen in Figures 5 through 8, elements for constructing silo walls may be composed of four sections, each section being open at the top and the bottom. This offers the advantage of a vertical through-flow of air, thus avoiding moisture problems. Each section is constructed of two strip-like sheets 33 and 34 arranged transversely. The ends of two longitudinal sheets 35 and 40 are secured to the sheets 32 and 34 by means of welding, for instance. The sheet 35 has an outwardly directed flange 36 and an inwardly directed flange 37. The latter flange is provided at its inner edge with a downwardly directed flange 38. In the same way, the sheet 40 is provided with an outwardly directed flange 41 and an inwardly directed flange 42. The inwardly directed flange 42 has a downwardly directed flange 43 at its inner edge. The flanges 42 and 37 are joined together by means of one or more spacers 44. As can be seen in the figures, the sheets 35 and 40 are arranged to constitute the non-parallel sides of the trapezium. The trapezium is open at the top and partially closed at the bottom. The flanges 43 and 38 are designed to be inserted in the opening 39, as can be seen in Figure 8 showing a silo wall built of two elements 45 and 46. This is also clear from Figure 7.

Claims

1. Container such as silo for slow-running powder and granular material, which container comprises wall elements consisting of stackable units (2A, 2B) having a cross-section in the shape of a trapezium preferably symmetrical with the smaller of the two parallel surfaces facing upwards, characterised in that each unit (2A and 2B) consists of a first pair of opposed plates (3, 5; 35, 40) diverging towards the lower end connected to a second pair of opposed parallel plates (17 and 34), the second pair of plates being perpendicular to the first pair of plates and secured preferably by means of gluing, welding or screw fastening, whereby each unit (2A and 2B) is hollow.

2. Container according to claim 1, characterised in that the diverging plates (3, 5) have L-shaped cross-sections, each plate having a side section (3-5) and a top section (4, 6) with said top sections (4 and 6) overlapping each other and forming the smaller of the two parallel surfaces and with said side-sections (3 and 5) being joined together at the bottom with a plate (7) with U-shaped cross-section the lower end of each side- section forming a downwardly directed flange or tongue (8, 9) with the corresponding bent part of the plate (7).

3. Container according to claim 1, characterised in that each diverging plate (35 and 40) is provided with an upper outwardly directed flange (36, 41) and a lower inwardly directed flange (37, 42), which lower flange (37, 42) is provided at its inner edge with a downwardly directed flange (38, 43), said flanges (38, 43) being inserted in an opening (39) formed by the outwardly directed flanges (36 and 41) of a lower unit.