WO2023150805A2 - An improved method of manufacturing a flexible container - Google Patents

Abstract

An improved method of manufacturing a flexible container is disclosed in which there is woven in selected areas of a length of fabric formed by a body of warp and weft yam threads where yarns in the weft are controlled in the intended load and pressure-bearing areas during weaving. Preferably, the area where tension is required of the yarns where product in the container is exerting pressure in the horizontal direction once filled being greater than the area where no or less load in the horizontal is exerted and during lifting where an area where no weft yarns are needed are reduced in weaving and therefore is greater in the tension of the body yarns in the horizontal load- bearing direction. Having increased weft yarns where a join or seam is needed. Having increased weft yarns where a lifting device or belt is attached to the fabric such needing a higher weft count for stitching or attaching and transferring load and reducing said weft where no lifting device is attached or where no tension is placed on the fabric by the join or attaching means force. Where such fabric is rotated 90 degrees and where the weft becomes the warp and the warp the weft and a lifting loop may be attached to the area of increased yarns or where a seam or join is made. A length of woven fabric being woven and cut and formed in such a manner as to reduce the amount of material used in a conventional method in production of such a flexible container bag. Summary and objective of the invention It is an object of the present invention therefore to overcome or substantially reduce these disadvantages, primarely the strengthening, increasing or reducing of the weft in the fabric where nessasary, which may be in various places and various lengths in a length of fabric used to make a flexible bulk container or any other type of bag with utility requiring such.

Description

DESCRIPTION OF THE INVENTION

According to one aspect of the invention, there is provided a method of making a flexible bag for the transportation of material, comprising the steps of weaving a base fabric on a loom but more specifically a circular loom from body yarns, and increasing or decreasing the weft yarns in selected areas during weaving of the base fabric in the intended load-bearing and non-load bearing directions, this may be accompanied with reinforced warp yarns in defined areas forming the fabric so-formed produced into a bag, and attaching lifting means to the bag or join with a seam, weld or glue at selected areas having the aforementioned increased weft yarns, the tension of the increased weft yams during weaving preferably being greater than the tension of the lesser weft yarns in the longditudinal load-bearing direction where there are little or no lateral forces in certain types of designs described herein and being greater in the area where lifting belts or lifting devices are attached in other designs described herein or a cobination of both.

The tension of the increased weft yarn is preferably controlled to be higher than that of the lesser yams. This achieved for example by using a programed servo drive or motor to increase and decrease the weft yarn, a programed servo motor is preferable as many paterns can be achieved for various bag types, this may also be achieved by a number of gears but would not be as efficient and be more complicated compared to a server or step motor.

Typicaly there are between 6 and 8 shuttles in a circular loom, each shuttle may contain different types of yams.

Because the weft yarns on a circular loom are on a bobbin in a shuttle, the type and width of the yam is important to get the maximum benefit of the desired pattern.

These yarns may be flat, fribrillated or multi fillamented.

In a typical constuction of the fabric described in this method a 5 mm yarn of 2300 denier with a 6 grams per denier strength, woven with 20 ends per 100mm will make a flat fabric with a strength of 300 kilograms per 100mm, when increased to 40 yarn ends per 100mm this will double to 600kg. This doubling will cause the 5mm yams to fold and tighten the fabric in this area, The warp ends may be of another width and denier and of another type .

What is important and is one of the objects of the invention is in a single or two point lift container bag and where the body of the bag is used for lifting, there is a substantial part of the body that does not contain any product or particulate, The inventor understands that this area of the fabric has no lateral load-bearing only longditudinal load or lift load, what is also understood that there is a certain amount of fabric that needs to be drawn together to form the lifting part of the Container bag By reducing the weft in this area the yarn or fibers are easier to draw together.

This will allow for a reduction in material and an increas in weaving output.

It is also understood that there are various tests that a FIBC must comply with, these being

1 Drop test

2 Pressure-bearing test

3 Topple test

4 Righting test

What the invention aims to overcome is to pass all these tests by decreasing the amount of raw material or yarns needed to to do the same in a convetional manner. According to another aspect of the invention, there is provided a flexible bag for the transportation of material comprising a body of textile material woven on a circular loom in the manner described herein, said flexible bag being very difficult and uneconomically to produce on a flat loom.

Said body of material being tubular and once cut to its desired shape is rotated 90 degrees whereby the weft now becomes the warp and warp becomes the weft.

The weaving of such a body of material allows for a variety of flexible bag designs that were not economically or able in the past.

What the invention aims to overcome is the making of coated bags with a base area greater than 900cm with reinforced or increased area of yarns by using a coating machine with a die of 2meters or less and such material made on a circular loom in accordance with the method of weaving described herein

It is understood that the hight of a FIBC bag cannot excede 2 times its base, therefore for tall coated bags a wide die coating machine is needed, to coat a circular woven material of 2 meters wide or 4 meter circumference with reinfoced areas in its warp direction a die greater than 2 meters is needed and such material needs to be run twice as both sides need to be coated.

With the method described herein, a fabric can be woven on a circular loom, slit on 2 sides and wound on to 2 seperate winders to produce a flat cloth now with areas of increased strength in the horizontal plane, and may also have reinforced or areas of increased strength in the longitudinal plane.

The said woven material can now be cut in accordance to a pattern woven into such said length of woven material and completed to form a Flexible container bag.

These designs and methods will be shown in the drawings

BACKGROUND OF THE INVENTION

This invention relates to containers for the transport of materials and more particularly to flexible intermediate bulk containers for the transportation of particulate material in bulk such as powders, pellets, granules, flakes, etc.

There are many methods of producing such container bags and improvments to the materials, machines and methods of construction are being made but there are still disadvantages in some areas.

Ultimately the invention must have an economical advantage whether it is in the material or the manufacturing process .

The invention covers both.

There are two main variables to consider when producing such container bags being the load in the horizontal direction and the load in the longitudinal direction.

The horizontal being pressure contained by the weft yarns and the longitudinal being load carried by the warp yarns.

Other considerations are the type of fabric used and the way such fabrics are produced and the way in which the fabric is used to make such container bags

The containers are intended to contain a substantial quantity of material, for example in the range of one half of a ton to two ton. A problem that arises in the construction of such a container, known in the art as an Intermediate Bulk Container (IBC), is that of providing adequate strength because the containers may be roughly handled and/or mishandled and subjected to impulsive forces by the crane or fork lift truck during lifting and transportation.

Common failure points are at the seams, on the base or body of the woven material or at the point of of attachment of a lifting loop to the main body of the container bag.

The company Mulox was the first to focus on overcoming the failure of the material at the point of attachment of lifting loops in a 4 point lift bag.

There have been many advancements in various fields related to FIBC container bags as in Mulox reducing the overall weight or use of materials in the production of FIBS container bags by reducing material in the non load-bearing area of the bag or the Omega type bag using a pleat to distribute the load more eavenly over the bag in the lifting or the developent by Norsk Hydro of a single point lift bag using the full strength of all the warp ends when lifting therby reducing the weight of the fabric used in a four point lift bag.

There are two types of looms, circular and flat.

There is also a complication in producing coated reinforced fabrics.

Reinforced fabric first invented by Charles Futerman when all production of woven materials for FIBCs were produced on flat looms.

The fabrics were mainly uncoated and coating technology for wide woven fabric was not really developed at the time

Fabrics for the use in FIBCs are now mainly produced on circular looms whether it is for pannel type bags or circular.

Starlinger who are a leader in circular loom technology and weaving polypropylene have a loom with the means of increasing and decreasing the weft insertions but is limited to two vairiables and is used to create a crammed weft area when there is a weft or warp break and have also has claimed to use it to stop freying when cutting plain woven fabric and with stitching the ends.

Circular looms are much faster, cheaper, simpler and more commonly used for the weaving of materials for FIBC container bags but lack the complexity of a flat loom.

This invention adds more complexity and variables to producing a fabric by means of a circular loom.

References to patents in this field are to Starlinger Co and Mulox and Norsk Hydro

The comon base size of a FIBC is 1 meter and the largest 1.2M therefor a circular fabric of two meters is produced and looms are not realy produced to make fabrics wider than this.

Most coating machines can handle 2 meter wide fabric but the coating of 2 meter wide tubular fabric is difficult and time consuming. BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the invention will appear from the following description of embodiments thereof, given by way of example only, with reference to the accompanying drawings, in which:

FIG 1 shows various flexible containers le and Id having a body and lifting loops fabficated from the body of the bag and le a variant of the invention

FIG. 1 and FIG 1.1 are a fragmentary view of the material of a fabric weave showing the top and side views of the said woven material used to produced the said intermediate bulk container in the invention;

FIG. 2 shows a cut length of fabric used to produce said container bag;

FIG. 3 shows a continuous length of woven fabric used to make one said type of container bag described in the patent and more so in FIGS 7,8;

FIG. 4 shows other variations of a weave used to produce flexible container bags at various stages;

FIG. 7 shows a diagrammatic view of a continuous length of a said woven fabric with a said woven pattern and a said cut pattern in the fabric together with perspective views of the flexible intermediate container at various stages in its manufacturer in accordance of at least one claim in the patent;

FIG. 8 shows a diagrammatic view of a continuous length of a said woven fabric with a said woven pattern and other said cut patterns in the fabric together with perspective views of the flexible intermediate container at various stages in its manufacturer in accordance of at least one claim in the patent;

FIG. 9 is a diagrammatic view of a cut length of a continuous woven fabric with a weave in accordance of at least one claim in the patent and the forming of a flexible container bag from such;

FIG 10 shows a diagrammatic view of a continuous length of a said woven fabric with a said woven pattern and other said cut patterns in the fabric together with perspective views of the flexible intermediate container at various stages in its manufacturer in accordance of at least one claim in the patent;

FIG 11 shows a length of a said woven fabric to make said container bag with a said woven pattern

Fig 12 shows a continuous length of woven fabric used to make a said type of container bag described in the patent FIG 13 shows a flexible intermi diate bulk container with lifting loops attached flat to the side walls of the body of the bag of the fabric cut length of fabric used to produce said container bag;

FIG 14 shows a flexible inteermidiate bulk container with lifting loops attached in between a folded pleat of the side walls of the body of the bag around the circumference

FIG's 15 and 16 show the side view of a wall of the container bag with the attached lifting belts

DETAILED DESCRIPTION

Referring to the drawings, there is shown in FIG. 1 a length of fabric la, the construction of the fabric described in the patent showing the warp 6 and weft 7 tapes and the different amounts in the different areas and a side view lb of the weft tapes 2,3,4 and the warp tape 5, 2 being its unfolded or compressed size 3 being half its original size and 4 a 14, 5 showing the different densities in each area.

FIG 1.1 shows a length of fabric 1.1a, the construction of the fabric described in the patent showing a reinforced or strengthened warp area 9 with warp tapes 6 and 7 and weft tapes 8 and the different amounts in the different areas and a side view lb of the weft tapes 2,3,4 and the warp tape 5, 2 being its unfolded or compressed size 3 being half its original size and 4 a 14, 5 showing the different densities in each area.

FIG 2 shows a full length of fabric cut to produce a flexible container bag 12a 12b

FIG 2 describes the different densities in the length of the fabric in various areas and reasoning for such

FIG 3 shows a length of woven fabric with different weft densities 1 being a high density weft 2 being the least dense weave, whose area contains no product and whose bodies weave is designed for lifting the said container bag, 3 shows the flexible containers area where the product is held and most lateral or horizontal force is exerted and whose bodies weave which is designed to carry the load in both directions when stacked and dropped, 4 shows various cutting points depending on the type of bag requirement. 5, 3a, 3b and 3c shows the various bags to be produced from the said length of woven fabric in the invention.

FIG 4 shows yet other variations of the weave claimed in the invention where the length of fabric 4a is woven on a circular loom and slit to form two lengths 4a and 4b, where 1 is the main body 2 and 3 are increased weft areas and, where 3 is used for attaching a lifting belt and where there are eight areas and 4 lifting belts and 10 is a cut point and separated and 2 is used as a strengthened area to sew a seam and join two ends to form the body of the bag which is further shown in FIG 9, the size of one of the areas 2 may be increased so as also to be used as an area where a seam is sewn to join the fabric to form the bag, the same area 2 is also used to attach a lifting belt and will result in a different pattern, the length also shows 4 being reinforced areas in the warp when woven, the lengths 4a and 4b show a weave pattern 4c, 4d, 4e used to produce a said flexible container in accordance with the invention.

FIG 7 shows yet other patterns and ways of assembling a flexible container bag, FIG 7 shows a Length of woven circular fabric and where 7a and 7.1a are separate bags and 8 is the main body and 1 are the integral lifting loops and 5 is a cut line.

FIG 7 shows the two bags 7a and 7.1a interlocked in their lifting areas and 6 showing a reduced area of weft insertions 2 being a base and 3 a seam and 4 being the finished lifting loop and where FIG 7 is a single point lift type bag.

FIG 8 shows yet other patterns and ways of assembling a flexible container bag more specifically but not limited to a two point lift bag and a four point lift bag and where strips 1 of body of the bag are joined at 12 and used to lift such bag and where such bag may have a bottom 11 and a top 13, such top and bottoms may have a filling or discharge spout

Such bag may also have a liner and be coated with a material and may be made with a woven material described in the patent where there are variations 4a and 4b in the weft at predetermined positions.

The sixteen integral extension’s 1 in 8b and 8e are joined in various configurations to form a single, two or four point lift bag. In 8x it shows a perspective top view of the sixteen extensions 1, 2, 3, 4, 5, 6, 7, 8, on one side and 1, 2, 3, 4, 5, 6, 7, 8 on the other, 8y shows 3 joined to 6, 4 joined to 5 and 1 to 8 and 2 to 7, these are all then joined together to form a lifting loop, the same will be done on the other side to form a second loop. 8G shows a 4 point lift bag where 3 is joined to 6 and 4 is joined to 5 and where a lifting loop is formed, the same is done to join 1 to 8 and 7 to 2, this is repeated on the other side.

In another 4 point configuration 3 is attached to 5 and 4 is attached to 6, 7 to 1 and 8 to 2. this is repeated on the other side.

The said attachments may vary, they may overlap each other and have another piece or strip of material between them where a seam or stitch is formed, they may be folded-over and stitched to form a seam or they may be brought together and stitched to form a seam.

They may also be joined by a webbing belt.

Fig 8i and 8i2 shows another variation of a flexible container bag in accordance with the invention which has four extensions and 1 is joined to 4 and 2 is joined to 3 and forming a loop at 12.

Fig 8x shows a flexible container bag with a top cover with a filling spout

Fig 9 shows yet another type of flexible intermediate container bag where 9a and 9b is a cut length of one bag with a weft pattern woven such that 1 forms the basic body of the bag and where 3 and 4 are areas of increased weft and where 2 and 5 show areas of reinforced warp.

Fig 9c, and 9f shows a flexible container bag assembled in accordance with the invention having lifting loops 6 attached at 9 in the area 3 and 2 and having a base 7 and side seam at 8, such side seam may be at any point depending on the pattern desired.

Fig 9d shows a length of material woven in accordance with the invention where 1 shows the main body and 10 an area of lighter warp and Il a higher warp area Fig 9g shows a attached lifting belt 6 or webbing between a pleat 13 of reduced weft 10 material attached by 12 a series of seams and a denser weft material 11 being part of the body 1 where such is made from a circular unslit material or fabric and which may also be used with a length of material shown in 9d and where the bag shown in 9f may be of a circular unslit material and where there is no seam at 4

Fig 10 shows a similar process and bag as in Fig's 8h and 8j what is added is the reinforced warps in the area 6, this may apply to any of the described bags and may be in any area where strength in the lifting direction is required.

Fig 11 show a length of cut fabric that will be used to construct the said flexible container bag with a strengthened weft woven area and other areas also with reinforce warp sections for attaching lifting belts

FIG 12 shows a continuous length of fabric woven in accordance of one of the patterns in the patent where 1 is an area of strengthened or higher weft insertions fabric in relation to 2 and where 1 is the area used to attach lifting belts or lifting devices also to 3 the reinforced warp areas and where 5 is a cut line where the length will be cut and separated into bags 3a, 3b, 3c so to construct the said container bag and where 4 is used to close the bottom if gusseted or to attach a base panel

FIG 13 and FIG 14 shows a flexible intermediate bulk containers with 1 a strengthened weft area where 4 lifting belts are attached to 5 a reinforce warp area and where 2 is an area with a lesser weft then that of the area 1 and where there is no lifting belts attached. 6 shows a strengthened weft area where a base panel is attached

FIG 15 and FIG 16 show a side view of the fabric where 10 shows the area used to attach 6 a lifting device or belt and is an area with a higher number of weft ends and a strengthened fabric and shows 11 an area of lesser weft ends or fibres as those in the area 10, the area shown in 10 also has more weft ends therefore allowing for a stronger bond to the 6 lifting belt or device 13 shows a method of attaching a lifting belt or device to a pleated or folded 10 strengthened area of fabric and where 12 shows a method of using stitching, another method could be ultrasonic welding or glue

Claims

CLAIMS 1 Varied weft insertions at defined positions in a length of a fabric used to make a flexible container bag and where the body of the bag is used to lift the bag and product contained in the bag

1.1 more specifically maximized at the base area of the bag where the largest pressure force is and reducing the weft as the pressure reduces towards the top of the position in the bag where the product being contained is at its highest and least pressure is exerted in the horizontal load-bearing direction

1.2 and reduced to its minimum where only the lifting load-bearing part of the body of bag begins

1.3 The minimum being a reasonably stable fabric with the minimum amount of weft ends

2 reducing the weft in a defined area

2.1 more specifically in the area that is the lifting part of the body of the container that bares no pressure in the horizontal load-bearing direction and contains no amount of product

2.2 and only bares load in the lifting or longitudinal load-bearing direction and where the weft tape only act to stabilize the fabric and

2.3 by reducing the weft ends making it easier to pull all warp ends to a single point thereby reducing the stress on the warp ends.

3 and again increasing the weft insertions at the point where a seam is formed and the fabric is stitched together to form a lifting loop

3.1 such loop may be formed by folding the said fabric over and stitching a seam

3.2 or laying one length or side over the other and sewing a seam in the area of higher weft ends

3.3 said container may not necessitate the increased weft in the seam area but is desirable for performance depending on the manufacturing and lifting process

4 said change in the weft construction will lead to an increase in the output of fabric produced on said weaving machine

5 said process can also be used to produce a container bag with reinforced areas or areas with Increased strength

5.1 where said area is used to attach a lifting loop or area is used to lift such container bag using the body or with an attached webbing or lifting device or belt

5.2 and or where a seam or side seam is needed

5.3 and such seam or side seam is reinforced or strengthened by the increase in weft ends

5.4 where such process is used with a coated woven fabric for a container bag

5.5 Said fabric with an area of increased weft is rotated 90 degrees so that the weft now becomes the warp once used to produce a said container bag

6 said weaving process uses multiple weft shuttles with multiple weft yarn bobbins

6.1 where such weft yarn is a flat yarn

6.2 where such weft yarn in a multi filament yam

6.3 where such yarn is fibrillated

6.4 where there are various types of yarns woven together

6.4.1 such yarn being polypropylene

6.4.2 such yarn being polyester

6.4.3 such yarn being PET

6.4.3 such yarn having a different tex a pattern cut into a length of fabric where

7.1 such pattern forms the top of two bags and

7.2 at least 1 strip that is an extension of the body of the fabric so as to be able to form part of a lifting loop

7.3 more so that the length of fabric is used efficiently to form a single, two or four point lift container bag and more specifically

7.4 where a body with 16 extensions are cut, the load is more evenly distributed over the body of the bag

7.5 and where such pattern is used with 16 extensions a variety of bags can be made

7.5.1 and where such body may have reinforced warp tapes in predetermined areas so as to increase the lifting strength

7.5.2 and have an increase or decrease in the weft insertions to increase or decrease the strength of the fabric in the horizontal load-bearing direction

7.5.3 and where a variety of cross corner loops may be formed

7.6 and where each bag may be opposing each other An area of reduced weft relative to another area in the body of woven material used to make a flexible container bag in claims 1 and 2 where such area is folded to form a pleat and

8.1 where a lifting loop or belt may be inserted and attached to such Varied weft insertions at defined positions in a length of a fabric is used to make a flexible container bag and where a lifting belt or webbing is attached to the bag and is used to lift the bag and product contained in the bag

9.1 more specifically maximized at the base area of the bag where the largest load-bearing force and pressure-bearing is and reducing the weft as the pressure reduces towards the top of the position in the bag where the lifting device, means or belt begins

9.2 and to increase again the weft in the area where the lifting device, means or belt is attached or required 0 reducing the weft in a defined area

10. Imore specifically in the area that is the part of the body of the container that bares less or no attachment force from the lifting belts and or securing agent than in the area where the attached lifting belts or device are in the longitudinal load-bearing direction and

10.2 no lifting belt or device is attached 1 reducing the weft in a defined area

11. Imore specifically the base area of the bag where the base is formed from the same length of fabric as the bag

11.2 where the base is formed from a gusseted fabric and

11.3 where the base has multiple layers of fabric

11.4 where the base is formed as a block bottom

11.4 reducing said weft where the base starts

11.5 and again increasing the weft insertions at the point where a seam is formed and the fabric is stitched together to secure the bottom said base may not necessitate the increased weft in the seam area but may be desirable for performance depending on the manufacturing and handling process