NZ207325A

NZ207325A - Flexible bulk container with permanent lifting handle made from flat woven material

Info

Publication number: NZ207325A
Application number: NZ207325A
Authority: NZ
Inventors: A Juel; B Omdal
Original assignee: Norsk Hydro As
Priority date: 1983-03-02
Filing date: 1984-02-29
Publication date: 1988-03-30
Also published as: DE3478921D1; JPS59174481A; NO151855C; TR25365A; BR8401008A; DK134884A; ES280269Y; JPH0446830B2; NO174818B; EP0118112A2; PT78164B; ES280269U; UA7086A1; FI840763A0; DK153012C; EP0118112A3; HK119293A; NO151855B; ES8502642A1; IE55554B1

Abstract

The flexible container has the lifting loops (6) joined together to form a permanent lifting handle. The loops are joined together at a lift area (4) by glue or a seam. The handle can comprise a piece of material (5) which at least covers the lower part of the lift area, pref. as a woven material sleeve. The lifting area is pref. less than a sixth of the circumference of the container. The handle can be fixed by sewing.

Description

<div class="application article clearfix" id="description"> 207325 Priority 2-5-9 3 1 1 ' • ' * » 1 i i » | ^ t ' 1 "'t i f , 8 t ( ^ Cornpiet9 Specification Faed-^'^^f; C!3SS: .. .§65£&& I22 ssajasiM* ;;;;;; Pi-ibiicstion Date: ,,, P-0. Journal, No: . N.Z. PATOfT 2 9 FEB 1984 Patents Form No.5. Patents Act 1953 COMPLETE SPECIFICATION "Flexible container to be filled with bulk material and method for its manufacture" WE, NORSK HYDRO a.s., a Norwegian Company, of Bygd/ay Alle 2, Oslo 2, NORWAY, hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: 207325 m The present invention relates to a method for manufacturing flexible containers to be filled with bulk material, the containers being of the type which provide integral lifting loops from flat-woven base material. The invention also relates to containers made by this method. Containers of the above-mentioned type have been used for some time and been found to be suitable for several purposes. Usually they comprise an inner bag or liner of impervious material. The container is usually first blown up by air before it is filled with free-flowing bulk material. Such a container is described in U.S. Patent No. 4.136.723. This container has a double bottom and is preferably equipped with two integral P. L. B. & A. * lifting loops having a total width substantially equal to half per. P V I I 7 I °^ t*ie conta^ner's ft-ircumf crcncc such that the lifting loops comprise all of the longitudinal fibres of the container. The container can be filled by using an apparatus described in GB-Patent No. 1.505.583, and it will then be standing on a floor or the like without any extra support. Its lifting handle can be placed on a hook or the like before the container is blown up and filled with bulk material. The container can then be made ready for further transport, and this process might comprise closing the inner bag and joining the lifting lciops by pressing them together and secure them in this position such that one obtains a suitable handle which easily can be placed on a hook or some other lifting means. - 2 - 207325 If a broad hook is applied to hang the lifting loops on during the filling operation, the wide . loops will be pressed together to a few centimetres and can be kept in this position by means of a tape. One will then obtain a well-defined handle which makes the container well suited for further transport, and this is described in EP-application No. 81108748.5 (publication No. 54145). However, it has been found that the above-mentioned process for making the container ready beforehand has certain disadvantages, as does making the container's lifting loops ready after filling. The capacity of the filling apparatus is reduced because of the time it takes for the operator to place the lifting loops onto a hook which will press them together. If this operation is carried out after the container is filled in order to improve the capacity of the apparatus, then the total filling operation will be more labour-consuming because an extra operator is needed for making the container's loops ready. Further, the container's form itself means that it is necessary to use filling apparatus of a special type in order to obtain efficient filling and an effective process for making such containers ready. The fact that such special filling apparatus is not available everywhere where filling of such containers can take place, has acccordingly hindered the widespread use of the container. The lifting loops, which may have a total width corresponding to half the container's perimeter, means that the process of joining together the loops to form one lifting handle becomes somewhat labour-consuming. The wide loops also result in certain disadvantages when the container is placed on the filling - 3 - 207325 apparatus or connected to it. Accordingly, there has been a need for making these operations easier and less 1abour-consuming. It is desirable to continue to use some form of lifting loops because of the good experience with integral lifting loops which after filling of bulk material in the container are joined together by tape for making a:lifting handle. During further transport of such containers such lifting handles are suitable for receiving lifting hooks, forks and other means for lifting and transporting the container. When fork trucks are used, a lifting device is connected to the forks, for engaging the lifting handle. It has further been found that the tape applied in certain cases can be damaged during the further lifting and transport of the container, and if lifting forks having sharp edges are used the load-carrying fibres of the lifting handle can be damaged. In such cases there is therefore a need for a better protection of the fibres in the lifting handle and a way of joining which can endure the strain when lifting forks are applied. An object of the present invention was to arrive at a rational way of making flexible containers with integral lifting loops equipped with a permanent lifting handle. Another object of the present invention was to arrive at a container having a permanent lifting handle which could endure the strain it would be exposed to during the use of the flexible container. - 4 - 207325 A further object was to be able to use all types of filling apparatus and lifiting devices, without needing special equipment. Manufacture of the lifting handle itself by joining the lifting loops at the filling station had been found to be rather labour-consuming and additionally it required special hooks on the filling apparatus. It therefore was considered desirable to make a lifting handle which did not require special lifting hooks, and the inventors soon found that it would be easiest to make the lifting handle at the same place as the container itself was made. If the empty container is equipped with a permanent lifting handle, the transport of such empty containers is more expensive than for the ususal containers because of the larger volume to be transported. But it was found that the filling operation itself became so much easier when one used containers having permanent lifting handles that the advantages were far. greater than the disadvantages of transporting empty containers. The a method of making present invention provides^a flexible container for filling with bulk material, said container comprising lifting loops formed integrally with the container, said lifting loops being permanently secured together along at least part of the lengths of said loops, so as to form a permanent lifting handle. The problem now was how the permanent lifting handle could be formed most appropriately. It was found that the method would vary somewhat according to what kind of base material the container was made from. For containers with integral lifting loops, in general there are two types of base material, - 5 - 207325 i.e. flat-woven or round-woven textile. The present invention provides a method for making a flexible container for filling with bulk material, said container comprising at least two lifting loops formed entirely from the side walls of said container and formed integrally with said container, wherein the container is made of flat woven material; said method comprising the following steps:- providing a rectangular strip of said material; folding towards the longitudinal axis of the material that portion of each of the longer sides of the material which lies adjacent the mid-point of the length of the material, said folded-over portions, the lifting loops, being overlapped along or adjacent said longitudinal axis; securing said overlapped portions of the lifting loops together to form a permanent lifting handle; securing the remaining portions of the longer sides together to form the side seams of the container; and securing the shorter sides together to form the bottom seam of the container. It was further found that preferably the total width of the lifting handle should be not more than 1/6 of the container's base perimeter. This provides a lifting handle which was appropriate and advantageous for all operations:- filling, handling, lifting, transport and discharge of the container. In certain cases it is desirable to avoid wear on the load-carrying fibres of the lifting handle formed in this way. In that case the lifting handle itself is equipped with an extra piece of material. This piece of material should at least cover the lower part of the lifting handle, i.e. that part which will lie against the lifting device, for instance a lifting fork, a hook or the like, when the flexible container is lifted and/or transported. This extra piece of material can also be in the form of a sleeve such that it surrounds the lifting handle. Said piece of material must be made from a strong material which can endure the strains it is exposed to and which can be joined to the — - 6 - ip. L. B. & A. wJfiL. ■3'#/n &L.B.&A. p.rCi^ 3' /"? in 20732b material of the lifting loops such that a permanent lifting point is obtained. This piece of material will preferably consist of woven material, for instance of the same type which is used in the container itself. By way of example only, the preferred embodiment of the present invention is described in detail with reference to the accompanying drawings, in which Figure 1 shows a flat-woven base material for a flexible container; and Figure 2 shows a lifting loop with a lifting handle seen from above. Figure 1 shows a flat-woven base material 1 consisting of two halves A and B, and with side edges 3 and a cut 8 which makes it possible to form a container having a double bottom. The parts of each of the side edges 3 which lie adjacent to mid-point line 2 of the length of the material are folded towards the longitudinal axis of the material, said folded - over portions forming the lifting loops 6 and being overlapped along or adjacent said axis. Preferably, the width of the overlap is less than or equal to 1/6 of the container's cireumf-oroRO-e, and in most cases said width is less than 1/10 of said aircumfcirence. - 7 - 207325 The side edges 3 will now be positioned as shown by the reference number 3'. The area 4 marked out on the lifting loops 6 is then joined by means of glue or preferably at least one seam. One can fasten a piece of material 5 over the area 4, for instance by means of a seam. The piece of material 5 can be fastened around the area 4 such that it takes the form of a sleeve. The material 1 is folded over the line 2 such that that halves A and B cover each other. Thereupon the container is sewn along the side edges 3 and at the bottom, thus forming a completely finished container with lifting loops 6 and a lifting handle 10 comprising the protecting piece of material 5. The piece of material 5 can be of woven material, for instance of the same type as that used in the container itself, or of some other suitable material which is strong enough to endure the strains it will be exposed to during further handling 6f the container. The piece of material 5 may have a distinctive colour so that the lifting point is clearly marked out, and it can also be used as a colour code for the type of container used or the. .. material which will be transported. On figure 1 there is shown the application of an extra piece of material 5, but the permanent lifting handle 10 can as previously mentioned also be made without this piece of material, that is, by just joining together the loops 6. 2073^5 Figure 2 shows in plan view lifting loops 6 with a lifting handle 10. The piece of material 5 which here is only fastened at the lower part of the lifting handle, is not visible on the Figure, but the seams 9 for fastening the piece of material 5 to the area 4 are shown. Each of the openings 7 are shown as equally large, but if so desired the opening which is to be used as filling openings can be made somewhat larger than the other one. - 9 - 207325 A container made according to the invention is ready to be connected directly to the filling apparatus. The filling pipe is put into one of the openings 7, and the container can be blown up by air and thereupon filled with free-flowing material. During the filling operation the lifting handle can be placed on a hook on the filling apparatus, but strictly speaking this is not necessary. It has in fact been found that the blown up container can stand freely and without substantial support sideways during the filling operation. As soon as the container is filled, it is necessary simply to close its inner bag, and then it is ready to be transported. The present invention provides a rational manufacture of a container having a permanent lifting handle. The filling of such readymade containers can be carried out quickly and easily with fewer operators than usually is necessary when one has to form the lifting point at the filling station. The filling operation itself will accordingly be greatly simplified, as placement of the container on special lifting hooks or forming of lifting handles is not necessary. The container will thereby be ready for further transport as soon as it is filled and the inner bag is closed. The capacity of the filling apparatus can be uitilized maximally, and the total operation for filling and making the container ready for further transport will be less labour consuming. - 10 - 207325 An essentitial advantage which is obtained by the present invention is that one is not dependent on complicated or special filling apparatus or lifting devices. Thus one can use lifting forks which easily can be put in under the well-defined lifting handle, which is so strongly made that it can endure several handling operations of the filled container without damage to the lifting handle or the lifting loops by the handling devices. Even when especially rough lifting devices are used, the lifting handle according to the invention comprising the protecting piece of material 5 will secure the fibres in the lifting loop against wear. - 11 - </div>

Claims

<div class="application article clearfix printTableText" id="claims"> 207325 WHAT WE CLAIM IS:

1. A method for making a flexible container for filling with bulk material, said container comprising at least two lifting loops formed entirely from the side walls of said container and formed integrally with said container, wherein the container is made of flat woven material; said method comprising the following steps:- (a) providing a rectangular strip of said material; (b) folding towards the longitudinal axis of the material that portion of each of the longer sides of the material which lies adjacent the mid-point of the length of the material, said folded-over portions, the lifting loops, being overlapped along or adjacent said longitudinal axis; (c) securing said overlapped portions of the lifting loops together to form a permanent lifting handle; (d) securing the remaining portions of the longer sides together to form the side seams of the container; and (e) securing the shorter sides together to form the bottom seam of the container.

2. The method fo claim 1 further comprising the step of securing an additional piece of a material over at least the underside of said lifting handle prior to securing the side seams of the container.

3. The method of claim 2 wherein the additional piece is of the same material as the container.

4. The method of any one of claims 1-3 wherein said lifting loops are secured together by glue.

5. The method of any one claims 1-3 wherein said lifting loops are secured together by stitching. - 12 - 20/325

6. The method of claim 1 further comprising fastening a sleeve around the lifting handle.

7. The method of claim 6 wherein said sleeve is made of woven material.

8. The method of any one of the preceding claims wherein said lifting loops are overlapped and the width of said overlap is less than or equal to 1/6 of the container's base perimeter.

9. A flexible container for filling with bulk material wherein said container is made by the method as claimed in any one of claims 1-8.

10. A method for making a flexible container substantially as herein before described and with reference to and as shown in the accompanying drawings. *3 AUG 1987 Norsk Hydro a.s. by their authorized agents P.L. BERRY & ASSOCIATES 13 </div>