EP0026822B1 - Method for making a transport package for calcium carbide - Google Patents

Description

The present patent application relates to a method for producing a transport packaging for calcium carbide for use in metered small quantities.

Up to now, it has been customary to pack small amounts of calcium carbide in metal drums, each drum containing about 100 kg of calcium carbide. The disadvantage here is that the drums only allow incomplete use of the loading area on the vehicle because of their round base. In addition, because of their relatively high purchase price, the empty drums have to be transported back from the place of consumption to the place of filling, which causes considerable additional freight costs, particularly for places of consumption located abroad. DE-C-2 033 160 discloses a device for metering moisture-sensitive solids such as calcium carbide, in which several containers are used which are square in their upper part and tapered at their lower end, these containers being used simultaneously for transport and storage serve the calcium carbide and each container holds about 1000 kg of calcium carbide. However, this device does not allow a sufficiently precise metering of small quantities, for example of 5 kg, since the tare weight resting on its pressure cells is too large in relation to it.

From US-A-3 670 880 a packaging for granular products in bags is known, which consists of a multi-layer corrugated cardboard container attached to a pallet. The bags are placed in the container and stacked beyond the height of its side walls. Over the stacked bags, a closure consisting of multilayer corrugated cardboard is pushed over, which comprises a flat upper part and downward-facing side walls and which partially engages around the side walls of the container. A shrinkable plastic film is placed around the top and side walls of the closure and around the side walls of the container and shrunk in a shrink oven at a temperature of about 150 ° C.

The container according to US-A-1 875 497 is constructed from four side walls and four upper and lower closure flaps, which are all connected to one another. After the lower flaps have been closed, a sack lying against its side walls can be inserted into the container, which can be filled with bulk material up to the height of the side walls. However, after the lower flaps have been closed, a cylindrical insert affecting the side walls can also be introduced, while in the area of the corners of the container a reinforcement tube is inserted which touches both the cylindrical insert and the side walls.

The container for handling loose material according to US-A-3 073 500 consists of an inner and an outer box which have been pushed into one another with the interposition of corner reinforcement angles. The boxes, which are spaced apart, are attached to a pallet. After filling the inner box with the loose material, the upper areas of the four sides of the inner box are first folded inwards and then the upper areas of the outer box designed as lids are closed.

From US-A-2 965 276 a pallet is known which consists of lower and upper ribs which are arranged with blocks spaced vertically apart. A plurality of ribs constructed in this way and spaced apart from one another are connected to one another by cross bars. A rectangular container is fastened to this pallet and can be closed with a lid. Containers and lids are encompassed several times by steel strips in the transverse direction.

In the method for packaging car coolers known from GB-A-1 512371, the coolers are stacked on a pallet between a flat bottom and a lid made of cardboard or plastic and strapped with metal straps. The coolers stacked in this way are completely encased in a shrink film. The shrink film is shrunk by treatment with hot air, which holds the cooler stack in place and seals the coolers.

According to FR-A-2 139 002, a polyethylene tube produced by a combined extrusion blow molding process is cut open with a wall thickness of approximately 0.1 mm, folded in a special form, welded in the transverse direction and cut to form sacks. Such a sack is brought over an essentially rectangular pallet load. After the pallet load is covered with the sack in this way, it is briefly exposed to temperatures of around 200 ° C in an oven, whereby the sack shrinks.

It is an object of the present invention to provide a method for producing transport packaging for calcium carbide in small quantities, in which expensive metallic packaging can be dispensed with and optimal use of the loading area of the transport vehicle and the amounts of carbide are precisely metered. This is achieved according to the invention in that a large number of sealed bags made of plastic film, preferably polyethylene film, filled with a predetermined amount of calcium carbide, with a thickness of 0.05 to 0.4 mm and a mass per unit area of 50 to 400 g / m ² packed in several layers one above the other in a box fastened on a pallet, made of multiple cardboard and then closing the box; that a ring insert is inserted in the box, which lies against the vertical inner walls of the box with the exception of the areas of its corners; that in each corner of the box there is a pipe section extending from its bottom to its lid, the pipe sections being affected by the ring insert while stabilizing their position; that the box has outer bottom and lid closure flaps which completely overlap each other; that a covering grate is placed on the top of the sealed box; that one straps the closed box, the cover grate and the pallet in the longitudinal and / or transverse direction at least once each with a band; that after the strapping, the box, the covering grate and the pallet are covered with a surface-based mass of 55 to 460 g / _M ² shrink film and the shrink film is shrunk by blowing with warm air; and that up to three pallets, boxes and cover grids covered with shrink film can be stacked on top of one another.

The method according to the invention can also be designed by strapping the closed box, the cover grate and the pallet twice in the longitudinal direction and / or in the transverse direction with a band.

In the method according to the invention, a single-use pallet, which is preferably designed as a two-way pallet (see DIN 15 145, August 1977), made of wood, which together with the box and the cover grate after removal of the calcium carbide at the point of use, for example by burning , is easy to remove.

The filling of the calcium carbide into bags made of plastic film and their gas-tight sealing by welding is advantageously carried out in the method according to the invention with a correspondingly constructed machine using a plastic tube. The mechanical handling on the one hand prevents moisture from getting into the bags and on the other hand guarantees precise dosing.

By placing a cover grate on the top of the closed box in the method according to the invention, on the one hand it is prevented that the strapping cuts through the upper edges of the box and on the other hand enables the stackability of the box covered with shrink film.

In the method according to the invention, the stackability of the boxes is increased in that pipe sections extending from the floor to the ceiling are arranged in their four corners.

Due to the ring insert located inside the box, the strength of the walls of the box is increased in the method according to the invention on the one hand and the position of the pipe sections is stabilized on the other hand.

Finally, the complete overlap of the bottom and lid closure flaps in the method according to the invention increases the strength of the bottom and lid of the box.

Calcium carbide in small quantities, for example = 5 kg, is used for the desulfurization of small amounts of molten iron in foundries, the calcium carbide in the bag being thrown into the molten iron. Calcium carbide in these quantities continues to be used to fill small acetylene developers.

• Fig. 1 eine Seitenansicht auf eine Palette, eine Schachtel und einen Abdeckrost,
• Fig. 2 eine Draufsicht auf eine Schachtel nach Linie II-II der Fig. 1.

The drawing shows the box, the cover grate and the pallet as used in the method according to the invention. It shows

• 1 is a side view of a pallet, a box and a cover grate,
• 2 is a plan view of a box along line II-II of FIG. 1st

A box 2 made up of several layers of cardboard 1 is firmly connected to a recessed two-way flat pallet 3 (see DIN 15 145, August 1977). A ring insert 4 is inserted into the box 2, which lies against the vertical inner walls of the box 2 - except for the area of its corners. In the corners of the box 2 are each tube sections 5, which run from the floor to the top of the box 2. In the corner areas, the ring insert 4 touches the pipe sections 5, whereby their position is stabilized. A cover grate 6 rests on the closed box 2. The pallet 3, the box 2 and the cover grating 6 are strapped twice in the longitudinal direction with a steel band 7 each.

example

In a box (length 120 cm, width 100 cm, height 82 cm) with mutually completely overlapping bottom and lid closure flaps, a ring insert made of corrugated cardboard and four tube sections made of cardboard are set at the corners. The box is glued to a return two-way flat pallet. 200 polyethylene bags (length 36.5 cm, width 28.5 cm, film thickness 0.1 mm), each filled with 5 kg calcium carbide and sealed gas-tight, are packed in several layers one above the other in the box. After closing the box, a cover grate is placed on its top. Cover grating, box and pallet are strapped twice in the longitudinal direction and once in the transverse direction with steel tape (thickness 2 mm, width 20 mm) before they are covered with a tube made of shrink film (thickness 0.2 mm). After the hose has been welded on, it is blown with warm air at 70 ° C and shrunk as a result.

Claims (2)

1. Provess for making a package for transporting calcium carbide for use in small metered quantities, wherein a plurality of bags made from a plastics sheet, preferably a polyethylene sheet having a thickness of 0,05 to 0,4 mm and a surface mass of 50 to 400 g/m², and being filled with a certain quantity of calcium carbide and closed, are disposed in varicus layers one above the other in a multi-layered card board box (2) mounted on a pallet (3), and the box (2) is closed; wherein the box (2) is filled with an annular member (4) which is in close contact with the vertical inside walls of the box (2) with the exception of the region of its corners; wherein each of the corners of box (2) is provided with a tubular trunk (5) reaching from its tottom to its cover the tubular trunks (5) being in contact tangentially with the annular member (4) stabilizing their positions; wherein the box (2) is provided with exterior bottom and cover closing flaps completely overlapping each other; wherein a covering grate (6) is placed on to the upper side of the close box (2); wherein the closed box (2), covering grate (6) und pallet (3) are encircled at least once in longitudinal and/or transversal direction by means of a tape; wherein after this encirclement, a shrinkable sheet having a surface mass of 55 to 460 g/m² is pulled over the box (2), covering grate (6) and pallet (3), and the shrinkable sheet is caused to shrink by blowing hot air thereonto; and wherein up to three pallets (3), boxes (2) and covering grates (6) are stackable.

2. Process as claimed in claim 1, wherein the box (2), covering grate (6) and pallet (3) are encircled twice in longitudinal and/or transversal direction by means of a tape (7).

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