INLINER

Abstract

The present invention relates to a flexible inliner (28) from a multi-layered plastics-material film, having an upper filling connector (30) and a lower retrieving connector (32), in particular for a pallet container (10) for storing and for transporting liquid and free-flowing filling goods. In order for the use of inliners in pallet containers to be improved and in particular for the barrier effect of the multi-layered film to be maintained also over comparatively long transportation and storage periods, it is provided according to the invention that the filling/retrieving connector (30, 32, 54) is welded to the inliner wall (56) in such a manner that existing film cutting edges (68, 70) are covered in relation to contact with the filling goods, and no film cutting edge (68, 70), neither the film cutting edge on the welded flange rim (58, 66) of the welded filling/retrieving connector (30, 32, 54) nor the film cutting edge on the internal-side delimitation of a retrieving opening (72) in the inliner wall (56), comes into contact with the filled liquid filling goods.

Claims

1. A multi-layered flexible inliner (28) from a plastics-material film, having at least one filling/retrieving connector (30, 32, 54) which is welded to an inliner wall (56) and has a welded flange rim (58) and which is likewise composed of plastics-material film for insertion into stable external containers for storing and for transporting in particular hazardous liquid or free-flowing filling goods, characterized in that the filling/retrieving connector (30, 32, 54) is welded to the inliner wall (56) in such a manner that existing film cutting edges (68, 70), the film cutting edge on the welded flange rim (58, 66) of the welded filling/retrieving connector (30, 32, 54) and the film cutting edge on the internal-side delimitation of a retrieving opening (72) in the inliner wall (56), are covered in relation to contact with liquid filling goods filled thereinto.

2. The inliner as claimed in claim 1, characterized in that the welded filling/retrieving connector (30, 32, 54) is of the same multi-layered film construction as the inliner wall (56).

3. The inliner as claimed in claim 1, characterized in that when welding the filling/retrieving connector (30, 32, 54) to the inliner wall (56), the same external film layers are welded to one another.

4. The inliner as claimed in claim 1, characterized in that the welded flange rim (58, 66) of the filling/retrieving connector (30, 32, 54) prior to the welding is aligned radially inward, wherein after the welding, a through opening which has approximately the same diameter as the retrieving opening (72) in the inliner wall (56) is configured within the welded flange rim (58, 66).

5. The inliner as claimed in claim 1 characterized in that the welded filling/retrieving connector (30, 32, 54) is turned inside out and pulled through the retrieving opening (72) in the inliner wall (56) in such a manner that the fitted welded flange rim (66) of the filling/retrieving connector (30, 32, 54) is disposed on the internal side of the inliner wall (56).

6. The inliner as claimed in claim 1, characterized in that the welded flange rim (58) of the filling/retrieving connector (30, 32, 54) is aligned radially inward and is welded to the internal side of the inliner wall (56) of the multi-layered inliner film by annular welds for the inliner body.

7. The inliner as claimed in claim 1, characterized by, a cuboid design for insertion into usual 1000 l pallet containers, in which three blanks of a multi-layered inliner film are welded to one another, wherein said three blanks are composed of an upper horizontal cover part (46) having a centric flexible filling connector (30), a lower horizontal base part (48), and a vertically encircling lateral wall part (52) having a flexible retrieving connector (32) on the base.

8. The inliner as claimed in claim 1, characterized in that the upper centric flexible filling connector (30) of the inliner (28) is fixedly welded into an upper centric filling connector (74) of a rigid plastics-material internal container (12), and the flexible retrieving connector (32) of the inliner (28) that is disposed on the base is fixedly welded into a retrieving connector (76) disposed on the base of a rigid plastics-material internal container (12) of a pallet container (10).

9. The inliner as claimed in claim 1, characterized in that the upper centric flexible filling connector (30) and/or the flexible retrieving connector (32) disposed on the base of the inliner (28) are/is fixedly welded so as to be axial on the end side of the upper centric filling connector (74), or fixedly welded so as to be axial on the end side of the retrieving connector (76) disposed on the base of the rigid plastics-material internal container (12) of the pallet container (10).

10. The inliner as claimed in claim 1, characterized in that the upper centric flexible filling connector (30, 54) and/or the flexible retrieving connector (32, 54) disposed on the base of the inliner (28) are/is fixedly welded so as to be radial in the external mouth region of the upper centric filling connector (74), or fixedly welded so as to be radial in the external mouth region of the retrieving connector (76) disposed on the base of the rigid plastics-material internal container (12) of the pallet container (10).

Description

[0019] The invention will be explained in more detail hereunder by means of an exemplary embodiment which is schematically illustrated in the drawings in which:

[0020] FIG. 1 shows an IBC having an inserted inliner according to the invention, in a front view;

[0021] FIG. 2 shows the inserted inliner according to the invention, in a perspective view;

[0022] FIG. 3 shows a schematic illustration of a welding and punching device;

[0023] FIG. 4 shows a schematic illustration of a welded inliner connector;

[0024] FIG. 5 shows a perspective partial sectional view about the region of an upper filling opening of an IBC plastics-material internal container; and

[0025] FIG. 6 shows a perspective partial sectional view about the region of a lower retrieving opening of the IBC plastics-material internal container.

[0026] In FIG. 1 a pallet container (IBC) having a filling goods volume of approx. 1000 l for storing and for transporting in particular hazardous liquid or free-flowing filling goods as a preferred exemplary embodiment is identified by the reference sign 10. The pallet container 10 for an application or use, respectively, with hazardous filling goods meets particular test criteria and is provided with a corresponding regulatory permit. The main elements of the pallet container 10 are composed of a thin-walled rigid internal container 12 which is produced from a thermoplastic plastics-material by the blow-molding method, a tubular grid frame 14 which as a supporting jacket tightly encloses the plastics-material internal container 12 and a base pallet 16 on which the plastics-material internal container 12 bears and to which the tubular grid frame 14 is fixedly connected. The external tubular grid frame 14 is composed of horizontal and vertical tubular rods 18, 20 which are welded to one another.

[0027] An identification plate 22 from thin steel sheet for identifying the respective liquid filling goods is fastened to the front side of the tubular grid frame 14. A retrieving fitting 24 for retrieving the liquid filling goods is connected on the front of the base of the plastics-material internal container 12. In order for the rigid plastics-material internal container 12 to be protected against contamination by the filling goods filled into said container and for multiple re-use of the valuable internal container to be enabled, a thin-walled inliner 28 according to the invention from a flexible multi-layered composite film is to be inserted in each case into the rigid plastics-material internal container 12 prior to the pallet container 10 being freshly re-filled, said inliner 28 at the top being connected to the filling connector 74 and at the bottom being connected to the retrieving connector 76 of the rigid plastics-material internal container 12.

[0028] Said flexible inliner 28 according to the present invention, which in this case is likewise cuboid, is schematically illustrated per se (without the enclosing plastics-material internal container 12) in FIG. 2. In contrast to the rigid plastics-material internal container 12 which when handled always remains dimensionally stable in any case, the inliner 28 per se, by virtue of the thin-walled property thereof, is not dimensionally stable but rather flexible, resilient, and adaptable. The wall thickness of the multi-layered inliner composite film is approx. 100 m to 300 m, preferably approx. 150 m. Given a specific area weight of approx. 100 to 150 g/m.sup.2, this results in a material weight of approx. 0.7 to 1.3 kg for a 1000 l inliner bag. The inserted inliners are produced from a multi-layered plastics-material composite film having an asymmetrical layered construction. The wafer-thin composite layers herein can be composed of various materials such as, for example HDPE/LDPE/EVOH/PET/PA/PP, or SiOx having layers from a bonding agent disposed therebetween, and/or be provided with a glass-fiber or woven-fabric reinforcement. Depending on the specific application, the composite film is equipped with barrier layers in relation to the diffusion of hydrocarbon, oxygen, aromatic substances, or water vapor, and optionally with antiseptic anti-bacterial coating, or a metal foil which contain vapor depositions of silver or aluminum.

[0029] The cuboid flexible inliner 28 in the front lower retrieving region has an inwardly directed wall concavity 34 which corresponds to the concave molding 26 in the shape of a protective housing of the rigid plastics-material internal container 12, having two lateral wall parts 36, one upper wall part 38, and one rearward wall part 40 having a flexible retrieving connector 32 which is molded to the latter and which is configured for bearing in a completely exact fit on the internal surface of the concave molding 26 which in the shape of a protective housing protrudes into the interior of the rigid plastics-material internal container 12. For the sake of improved clarity, this wall concavity 34 of the inliner 28 here is illustrated so as to be very box-shaped. The walls and wall transitions can of course also be configured so as to be heavily radiused, flattened and/or mutually transitioning, but in any case are to be adapted to the respective concave molding 26 in the shape of a protective housing of the rigid plastics-material internal container 12.

[0030] In terms of production technology, the body of the flexible inliner 28 is assembled by welding three blanks of a multi-layered composite film having an asymmetrical layered construction. Said three blanks are composed of an upper cover part 46 having the centric flexible filling connector 30, a lower horizontal base part 48 having a recess that corresponds to the shape of the base of the wall concavity 34, and a vertically encircling lateral wall blank 52 having sub-portions in terms of faces for the two lateral wall parts 36, as well as the upper wall part 38 and the rearward wall part 40 of the wall concavity 34 of the inliner 28, as is illustrated in FIG. 2. In the case of a completely produced inliner, the three blanks are welded together by way of two weld seams 42, 44 which are horizontally encircling on the external edge of the upper cover part 46 and on the external edge of the lower base part 48, and for closing the lateral wall blank 52 by way of the weld seam 50 which in the center of the front wall and through the center of the wall concavity 34 runs vertically from the top to the bottom. The particular welding of the flexible filling connector 30 and retrieving connector 32 will be described hereunder.

[0031] The state prior to the welding of a filling/retrieving connector 54 is schematically illustrated by means of a double-layered inliner film (TwinLiner) in FIG. 3. The two layers of the inliner film are composed of dissimilar materials and thus represent a simple asymmetrical film construction. In an asymmetrical film construction of an inliner film it is important that the same film material, or the same film layer, respectively, of the individual blanks and tubular filling and retrieving connectors are at all times welded to one another. In the case of all parts to be welded, the internal side of the parts which comes into contact with the filling goods is expediently first turned outward. To this end, the blanks, or tubular films, respectively, of the vertical inliner wall as well as the tubular filling/retrieving connector are turned inside out and turned to the wrong side, so to speak. After the inliner connectors have been welded, all parts are turned back, or reversed, respectively, to their normal positioning.

[0032] It is important in this instance that the welded flange rim 58 of the filling/retrieving connector 54 prior to welding is aligned radially inward. The welded flange rim 58 which is aligned radially inward, by means of a pressing tool in the form of a cylindrical counter bearing 62 (this counter bearing can also be referred to as a welding tube), is pressed against the internal side of the inliner wall and welded by means of an annular welding device 60. As the tubular filling/retrieving connector 54 is folded radially inward onto the cylindrical counter bearing 62, thin creases are inevitably formed in the film of the welded flange rim 58, said creases in the subsequent welding of the welded flange rim 58 by way of the annular welding device 60 however being completely ironed out so as to be flat and smooth in relation to the inliner wall. A rib-type reinforcement of the welded area in association with an increased strength of the welded connection is derived on account of the additional film material of the thin creases.

[0033] A through opening which is within the welded flange rim 58, 66 and has a clean film cutting edge 68 is configured directly after the welding by means of an annular punching blade 64 which is pushed against the cylindrical counter bearing 62, said through opening having the exact same diameter as the retrieving opening 72 in the inliner wall 56 that is punched, or cut, simultaneously so as to have a clean film cutting edge 70.

[0034] After the welding of the tubular filling/retrieving connector 54, the latter is again turned inside-out and pulled through the retrieving opening 72, which has just been cut in the inliner wall 56, to the outside onto the external side of the inliner body, as can be seen in FIG. 4. Here, the external side is illustrated at the top, and the internal side of the inliner body is illustrated at the bottom, as an exemplary embodiment for an upper filling connector of an IBC. In order for the inliner according to the invention to be implemented it is in any case important that the annular welding of the welded flange rim 58 of the filling and retrieving connector 30, 32, 54 to the inliner wall 56 in terms of production technology has taken place prior to the complete and final welding of the blanks of a multi-layered inliner film for the closed inliner body.

[0035] The filling region of the rigid plastics-material internal container 12, having the filling connector 74 molded thereon and the filling connector 30 of the flexible inliner 28 welded thereto, can be seen in a partial sectional illustration in FIG. 5. The flexible filling connector 30 by way of the welded flange ring 66 is welded to the upper side of the inliner 28, on the one hand, and by way of an annular weld seam 78 by radial welding is welded in a rotationally secure manner to the top in the internal side of the rigid filling connector 74 just below the end side of the rigid filling connector 74, said welding being in each case gas-tight and liquid-tight.

[0036] Finally, the retrieving region of the plastics-material internal container 12, having the rigid retrieving connector 76 molded thereon and the retrieving connector 32 of the flexible inliner 28 welded thereto at the end side can be seen in a partial sectional illustration in FIG. 6. For improved clarity, a quadrangle has been cut out of the wall of the rigid plastics-material internal container here, wherein the section line runs through the retrieving connector 76, through the protective housing 26 molded therein, and a small piece of the front wall of the plastics-material internal container 12, such that in the cut-out quadrangle the inliner 28 bearing therein by way of a curved wall concavity 34, identified by a multiplicity of vertical lines, can be seen. Furthermore, the obscured left rear part of the wall concavity 34 is indicated by dashed lines. It can be clearly seen in the quadrangular cut-out that the flexible retrieving connector 42 on the inside, or the rear side, respectively, by way of a narrow welded flange rim 66 is welded to the rearward wall part 40 of the wall concavity 34 of the inliner 28, and on the external side by way of an end weld seam 80 by way of axial welding is welded to the end face of the rigid retrieving connector 76, said welding being in each case in a gas-tight and liquid-tight manner. The inliner 28 by way of the shape-adapted wall concavity 34 bears on the full face, like a second skin, on the internal surface of the concave molding 26 of the rigid internal container 12. A substantial advantage of such a second-skin inliner lies in that the film back does not need such a high tear strength in relation to thrashing when being filled, or when the liquid filling goods slosh back and forth in movements during transportation, as to date, since no movement of any kind of the inliner film material takes place because the latter bears in a fixed and permanent manner on the internal side of the plastics-material internal container 12, as if adhesively bonded thereto, so to speak. On account thereof, more cost-effective film materials than to date, which are sensitive to tearing and have high barrier properties, can now also be used.

[0037] The upper flexible filling connector 30 as well as the lower flexible retrieving connector 32 of the flexible inliner 28 are expediently produced from the same film material having the same barrier properties as the film material of the flexible inliner 28. However, in the case of the inliner 28 according to the invention, the filling/retrieving connectors 30, 32, 54 are equipped with the same barrier properties as the inliner 28 per se, and disadvantageous diffusion procedures which penetrate the plastics material are precluded. In the case of an asymmetrical film construction of the internal film it is important that the same film material, or the same external film layer, respectively, are in each case welded to one another in the annular welding of the welded flange rim of the filling/retrieving connector to the inliner wall.

[0038] Instead of being inserted into the pallet container which has been described in detail and has its peculiarities, the inliner according to the invention, in a correspondingly adapted shape, can of course also be inserted into any other liquids container such as, for example bunghole drums or canisters from steel or plastics material.

CONCLUSION

[0039] The specific production, or constructive design embodiment, respectively, of an inliner according to the invention advantageously results in a film construction in which no open cutting edges of the multi-layered film point towards the filling goods, and wherein the correct surface is always directed inward. On account thereof, the barrier effect of the multi-layered film when in direct contact with the liquid filling goods is in particular fully preserved even over comparatively long transportation and storage periods, and any disadvantageous influence on or damage to the high-value filling goods by diffusion procedures from the inside to the outside (aromatic substances) or from the outside to the inside (oxygen) through the composite film is avoided on account thereof.

TABLE-US-00001 List of reference skins 10 Pallet container 12 Plastics-material internal container 14 Tubular grid frame 16 Base pallet 18 Horizontal tubular rods (12) 20 Vertical tubular rods (12) 22 Identification plate 24 Retrieving fitting 26 Concave molding (12) 28 Inliner (film bag) 30 Filling connector (28), flexible 32 Retrieving connector (28), flexible 34 Inliner concavity (28) 36 Lateral wall parts (34, 28) 38 Upper wall part (34, 28) 40 Rearward wall part (34, 28) 42 Upper horizontal weld seam 44 Lower horizontal weld seam 46 Upper horizontal cover part (28) 48 Lower horizontal base part (28) 50 Front vertical weld seam (52) 52 Lateral wall blank (28) 54 Inliner connector 56 Inliner wall 58 Inliner flange, radially inward 60 Welding device, annular 62 Cylindrical counter bearing 64 Annular punching blade 66 Welded flange ring (28) 68 Film cutting edge, flange ring 70 Film cutting edge, inliner wall 72 Retrieving opening, inliner wall 74 Upper filling connector rigid (12) 76 Lower retrieving connector rigid (12) 78 Radial welding, inward 80 Axial welding, end side