FORM-2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2006
COMPLETE SPECIFICATION
(See section 10; rule 13)
TUNNEL LIFT BAG
FLEXITUFF INTERNATIONAL LIMITED
an Indian Company,
of C-41-50, SEZ, Sector-3, Pithampur 454 775,
Dist. Dhar, Madhya Pradesh, India.
Inventor: KALANI, Saurabh
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.

FIELD OF DISCLOSURE
The present disclosure relates to flexible containers. Particularly, the present disclosure relates to bags used for storage and transportation of building materials.
BACKGROUND
Storage and transportation of bulk materials for industrial consumption is unavoidable in the sense that various raw materials and or semi finished products required to sustain the industrial activity is never available in the immediate vicinity of the unit. This led to various types of containers and storage systems specially adapted to suit the requirements of a particular type of industry. For example, methods of transportation and storage used for iron ore from the mining area to the smelting plant will not be suitable for transportation of raw materials required for the production of chemical or pharmaceutical products.
In a manufacturing unit it is possible to build specific handling and storage facilities like conveyor belts, bucket elevators and storage silos to receive and store bulk materials as the quantum of consumption is clearly known and remains constant for a known rate of production. The situation however is very different in a building site. It is not feasible to provide permanent storage and handling facilities as the same would be of no use once the construction activities are completed and would have to be uprooted and shifted to another site, involving prohibitive cost. Also the quantum of storage of materials like sand, gravel and cement and the like vary widely through the various stages of completion of the building.
This has lead to the use of cheaper and flexible storage means and use of standard handling facilities like mobile cranes and fork-lift trucks. Builder bags are

typically used for filling sand, aggregates and gravel. In some countries, typically, the U.K. these materials can not be dumped on ground and hence they are stored and transported in these bags. Each bag is typically of 1000 Kg. The use of flexible bags made of woven fabric with some reinforcement material PP/HDPE/LDPE/Metallic wires are known in the prior art.
Prior art builder bag is substantially square in open cross section and are provided with loops at the four top corners. The bag has a flat bottom suitably reinforced to with stand the designed load and four side walls. The loops are hooked to cranes lifting hook and used to lift and shift a loaded bag. These bags are invariably loaded on wooden or polymer pallets, as this facilitates lifting and shifting at a later stage, by using fork-lift trucks. Such bags are loaded on flatbed trucks along with pallets and are delivered to a building site where the unloading is done normally by fork-lift trucks. These pallets are expensive as they are provided with fork-lift tine entry access on at least two sides to facilitate easy handling and storage. The pallets are made of members having high cross sectional area to withstand storage loads and wear and tear encountered in rough and often careless handling, adding to their cost. Many of the pallets are also damaged and at times not returned to the original owner. The cost of a pallet is many times higher than the cost of a builder bag.
This led to the development of Tunnel lift bags as these bags could be transported without pallets in a truck and unloaded at the site by using standard fork-lift trucks. Tunnel lift bags were designed as seen in figure 2 of the accompanying drawings.
In case of tunnel lift bag, the bag has tunnels made of fabrics on two sides of the bag in addition to the four loops on the top corners. These loops are slung on to

mobile crane hook and used for lifting where as the side tunnels are used by a fork lift truck, as a tine entry access for handling the bags.
This design eliminates the use of pallets for fork lift handling but the problem is that the tunnel has reinforcement only at the edges and the center of the tunnel is not strong enough. This results in tearing off the tunnels when the fork lift tine is entering the tunnels as the tunnel flap is not in a fully open position and may accidentally tear off in the middle.
Another problem is that in windy conditions and or if two bags are positioned close to each other the tunnel flaps does not open out fully to permit easy entry of the fork lift tine into the tunnel requiring another workman to open the tunnel so that the fork lift driver can guide the tine into the tunnel. These bags are normally stored in two or three tier stacks and the use of additional workman not only adds to the cost of handling but also has other inherent short comings from a safety angle as the workman, has to climb up the stack to hold the flap in open position and accidents while assisting in insertion, of the tine into the tunnel cannot be avoided.
Several attempts have been made to manufacture a builder bags.
Accordingly, EP1023232 discloses a bag for transporting and storing bulk goods by means of a lifting strap which are fixed along the vertical edges of the bag. An additional strap is provided on the lifting strap for providing reinforcement. These additional straps are required to be separately stitched to provide the required reinforcement. This increases the cost of production and also increases the time required for production.

Hence, there was felt a need for a tunnel lift bags which could overcome the disadvantages of the prior art.
OBJECTS
Some of the objects of the present disclosure which at least one embodiment is adapted to provide, are described herein below:
It is an object of the present disclosure is to ameliorate one or more problems of the prior art or to at least provide a useful alternative.
One of the objects of this disclosure is to provide a flexible lift bag that does not require a pallet for storing and handling.
Yet another object of this disclosure is to provide a flexible lift bag that has a set of lifting loops or webbings suitable for use either with a crane or a fork lift truck.
Yet another object of this disclosure is to provide a flexible lift bag that has a set of loops or webbings which are easily hooked to a crane hook and to a fork lift tine.
Yet another object of this disclosure is to provide a flexible lift bag that can be lifted and positioned by a fork lift truck operator without the use of additional man power.
Yet another object of this disclosure is to provide a flexible lift bag that is simple in construction.

Yet another object of this disclosure is to provide a flexible lift bag that is robust.
Yet another object of this disclosure is to provide a flexible lift bag that is easily storable when empty.
Yet another object of this disclosure is to provide a flexible lift bag that reduces the turn around time of a truck by improving the efficiency of loading and unloading operations.
Yet another object of this disclosure is to provide a flexible lift bag that circumvents the problems encountered in opening of a closed up side tunnel.
To eliminate the problems of the loop and the tunnel lift bags of the prior art a builder bag has been envisaged in accordance with this disclosure which is illustrated in figure 3 of the accompanying drawings.
Other objects and advantages of the present disclosure will be more apparent from the following description when read in conjunction with the accompanying figures, which are not intended to limit the scope of the present disclosure.
SUMMARY
A material handling bag is disclosed in accordance with an embodiment of the present invention. The material handling bag includes an operative bottom face, a plurality of side faces, a plurality of loops, and a pair of tunnels. The plurality of side faces along with said operative bottom face configure an enclosure with an open operative top for facilitating filling of the enclosure. The first pair of opposite side faces extends beyond a second pair of opposite side faces. The loops are

disposed along the operative top edges of the side faces at four corners of said open operative top of the enclosure. The tunnels are configured from the first pair of opposite side faces. The tunnels receive tines of a fork of a fork lift truck, thereby facilitating suspending of the material handling bag on the fork, such that walls of the tunnels are extending above the top edges of the second pair of opposite side faces in the suspended configuration of the material handling bag. At-least some of the faces and the tunnels have strategically inherently disposed reinforced portions.
Typically, at-least some of the faces and the tunnels are configured from a U-panel.
Generally, the strategically inherently disposed reinforced portions are configured during weaving.
Alternatively, the strategically inherently disposed reinforced portions are configured by folding.
Generally, the strategically inherently disposed reinforced portions are reinforced with synthetic filaments.
Alternatively, the strategically inherently disposed reinforced portions are reinforced with natural filaments.

Typically, the loops are also configured from U panels.
Generally, the strategically inherently disposed reinforced portions are disposed at edge portion of said U panels.
Alternatively, the strategically inherently disposed reinforced portions are disposed at center portion of said U panels.
Generally, the loops are integral to the material handling bag.
Alternatively, the loops are additionally fitted to the material handling bag.
Preferably, an operative top end of each of the tunnel extends beyond the operative top edges of the side faces of the material handling bag.
Similarly, an operative top end of each of the loops extends beyond the operative top edges of the side faces of the material handling bag.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
Other aspects of the invention will become apparent by consideration of the accompanying drawing and their description stated below, which is merely illustrative of a preferred embodiment of the invention and does not limit in any way the nature and scope of the invention.
Figure 1 and Figure 2 illustrate a conventional lift bag;
Figure 3A illustrates a panel in accordance with the present invention;

Figure 3B illustrates a panel in accordance with another embodiment of the present invention;
Figure 4 illustrates a bag in accordance with one embodiment of the present invention;
Figure 5A illustrates a side panel in accordance with the present invention;
Figure 5B illustrates a side panel in accordance with another embodiment of the present invention;
Figure 6 illustrates a bag in accordance with one embodiment of the present invention with the side panel of Figure 5 A;
Figure 7 illustrates a bag shown in Figure 4 and Figure 5A being lifted by a fork lift truck;
Figure 8 and Figure 9 illustrate a panel in accordance with a second embodiment of the present invention;
Figure 10 illustrates a bag in accordance with the second embodiment;
Figure 11 and Figure 12 illustrate a side panel in accordance with second embodiment of the present invention;
Figure 13 illustrates the bag in accordance with the second embodiment with the side panel shown in Figure 11 and Figure 12;

Figure 14 illustrates the bag shown in Figure 10 and Figure 13 being lifted by a fork lift truck;
Figure 15 illustrates a panel in accordance with a third embodiment of the present invention;
Figure 16 illustrates the tunnel formed from a panel in accordance with a third embodiment of the present invention; and
Figure 17 illustrates a bag in accordance with the third embodiment.
DETAILED DESCRIPTION
The invention will now be described with reference tothe accompanying drawings which do not limit the scope and ambit of the invention. The description provided is purely by way of example and illustration.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific

embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
Figure 1 and Figure 2 illustrate a conventional lift bag (1) made of either a U-panel or 4-panel construction where the U-panel and 2 side panels are stitched to make the bag (1) or 4-panel with a bottom panel are stitched together to make the bag (1). Loops (2) are provided and stitched onto the corners which extend beyond the height of the bag (1).
A tunnel (3) may be stitched onto the opposite sides of the bag (1) either by a separate piece of fabric or made out of side wall of the bag (1). In case of a tunnel bag where the bag is made out of the same fabric, a webbing or reinforcement (not shown in figure) is stitched to both corners of the panels to make the bag (1) so as to provide structural strength. However, providing the structural reinforcement (not shown in figure) increases the cost of production of the bag (1).
Referring to the accompanied drawings, a tunnel lift bag or a material handling bag, in accordance with this invention is generally referred by the reference numeral 10 and is particularly shown in Figure 4, Figure 6, Figure 10, Figure 13 and Figure 17 of the drawings.

In accordance with one embodiment, shown in Figure 6, the tunnel lift bag (10) is made out of at least one panel (12). The panel (12), shown in Figure 3A or its modification shown in Figure-3B, may be a U-panel (14) or side panel (16). The tunnel lift bag (10) is made by using one U-panel (14) and two side panels (16) or five side panels (16) with one of the side panels (16) forming a bottom panel. The panels (12) are woven such that the fabric edge is formed by using the same material and the density of warp being woven in fabric is increased substantially by more than 25%. As shown in Figure 3A, the panels (12) may be provided with edge portions "A" having a higher density which can vary from 2 cm to 25 cm along two parallel edges. The edge portions with higher density may be provided on the U-panel (14), as shown in Figure 3A, or on the side panels (16), as shown in Figure 5A. Further, in accordance with another embodiment of the present invention the high density which may vary from 2 cm to 25 cm along the length (parallel edges) and in the centre of the panel as shown as "B" in Figure-3B. The higher density may be provided on U-panel (14) as shown in Figure-3B or side panel (16) as shown in Figure-5B.
The panels (12) are assembled to form bags open on one side and having tunnels (18), shown in Figure 4, or loops (20), shown in Figure 6. The tunnel (18) or the loop (20) may be formed from the U panel (14) or the side panel (16). The tunnel (18) or the loop (20) may extend beyond height of the bag (10). The tunnels (18) are configured on opposite side faces of the material handling bag and receive tines of a fork of a fork lift truck, thereby facilitating suspending of the material handling bag on the fork, such that walls of the tunnels (18) are extending above the top edges of the side faces in the suspended configuration of the material handling bag.
The length of the fabric piece forming the tunnel (18) is made by cutting U-panel (14) or by side panel (16) such that the total length of the panel (14 or 16) is at least 40% to 250% more than the height of the bag (10). The length of the fabric

piece forming the tunnel (18) is folded from the open end of the bag (10) towards the outer surface so as to form the tunnel (18). The edge of the panel (12) forming the tunnel (18) is stitched on the edges of the formed box (10) so as to be shaped as shown in Figure 4 and Figure 6. The stitching can be done either on full length of the bag (10) or part length of the bag (10) to fix the length of the fabric piece forming the tunnel (18) to the bag (10).
The loops (20) may be integral or additionally fitted to the bag (10) as shown in Figure 4 and Figure 6 for aiding in additional handling of the bag (10).
In accordance with another embodiment, the bag 10' shown in Figure 10 is configured from panel 12' that is having additional width (24') as shown in Figure 9. Similarly, in accordance with still another embodiment of the present invention the bag 10" shown in Figure 13 is configured from panel 12" that is having additional width (24") as shown in Figure 12.
The additional width (24') of the panel (12') and additional width (24") of the panel (12") is folded to form a sleeve and stitched back on the panel (12') and 12" respectively such that the width of the panel (12') and panel (12") is equal to the width of the bag (10') and bag (10") as shown in Figure 10 and Figure 13 respectively. The additional width (24') and additional width (24") of the panel (12') and panel (12") can be stitched either along the full length of the bag (10') / the bag (10") or a part length of the bag (10) / the bag (10") to attach the additional width (24') and additional width (24") of the panel (12') and the panel (12") to the bag (10') and bag (10") respectively.
In accordance with still another embodiment, shown in Figure 17, the panels (12"') are prepared by stitching an additional piece of fabric (24'"), shown in figure 15, onto the panels (12'") so as to form the tunnel (18) or the loop (20) onto

the two opposite sides of the bag (10'"). The tunnel (18) and/or the loop (20) are formed such that the top of the tunnel (18) and/or the loop (20) extends beyond the open edge of the bag (10'").
The additional piece of fabric (24/24724"/24"') is prepared by using a tubular fabric or a flat fabric of 50 GSM to 200 GSM so as to be folded at the edges so as to form stiff edges. The width of the additional piece of fabric (24), after being folded, is approximately equal to width of bag. The additional piece of fabric (24) is stitched onto the U-panel (14) or the side panel (16), as shown in figure 16, so as to form the tunnel (18).
The additional width (24), as shown in Figure 9, forming the sleeve when folded over the panel (12) may be provide with an additional reinforcement of fabric which can be inserted through the sleeve to provide for higher strength and durability to the bag (10).
Figure 7 and Figure 15 illustrates the bag (10) being lifted by means tunnels and/loops by a fork lift truck.
TEST SET-UP
Tests were conducted to determine effectiveness of the material handling bag/lifting bag of the present invention. The material handling bag/lifting bag was filled with a load weighing 1,000 Kg and under SWL @ 5:1 SF loading conditions. The material handling bag/lifting of the present invention was tested on a fork-lift truck. The results are as under:

Design SWL SF Result Remarks
FIL Design - Tunnel 1,000 5:1 5,200 Side Panel torn from the
formed with side Kg. Kg- base seam.
panels
Tunnel made with 1,000 5:1 5,100 Side Panel torn from the
additional piece of Kg. Kg- joint where the Tunnel
fabric and Panel is attached.
reinforced with
webbing stitched
with Side Panel.
Tunnel made with 1,000 5:1 4,900 Tunnel Fabric torn from
tubular piece of Kg. Kg. the tope folded edge.
fabric and stitched
with Side Panel.
From the above results, it was observed that the Side Panel forming the Tunnel itself breaks at the bottom seam where Side Panel and Bottom Panel ("U" Panel) are joined together. Cyclic load always comes at the centre of the Side Panel and Bottom Panel seam area. So, there was a possibility of further improvement.
That is the reason why Tunnel Fabric was made by giving additional density in warp by 15 cm at the centre to increase the strength of the Tunnel Fabric.
FIL Tunnel Lift Bag was further tested for observations. The results are as under:

Design SWL SF Result Remarks
FIL Design - Tunnel 1,000 5:1 5,600 Side Panel torn at the
formed with side Kg. Kg- place where the Tunnel
panels and forming starts.
additional

reinforcement by
increased density in
warp.
It was found from observations of the above results that there was further possibility of improvement in the Tunnel forming area. So, additional density on the edges of Side Panel by 15 cm was provided to increase the strength along the edges.
With the above changes, the Tunnel Lift Bag was again tested. The results are as under:

Design SWL SF Result Remarks
FIL Design - Tunnel 1,000 5:1 5,800 Side Panel torn from
formed with side Kg. Kg. where the Tunnel forming
panels and starts.
additional
reinforcement by
increased density at
the centre as well as
both the edges.
In lieu of the above tests and observations, the Tunnel Lift Bags were having 80 cm length, 80 cm width and 98 cm height:

TECHNICAL ADVANTAGES
The product as described herein above offers several advancements over similar products disclosed in the prior art. The bag of the present invention is easy to manufacture and is cost effective. The bag is durable and had longer life as compared to the conventional bags.
During transportation / lifting of the bag load always comes at the centre of the side panel and edges of the tunnel. High density gives reinforcement in the fabric and increases the durability of the bag.
Wherever a range of values is specified, a value up to 10% below and above the lowest and highest numerical value respectively, of the specified range, is included in the scope of the invention.
In view of the wide variety of embodiments to which the principles of the present invention can be applied, it should be understood that the illustrated embodiments are exemplary only. The numerical values given of various physical parameters and dimensions are only approximations and it is envisaged that the values higher or lower than the numerical values assigned to the parameters, dimensions and quantities fall within the scope of the invention.
Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

The use of the expression "at least" or "at least one" suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the invention as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the invention, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the invention. These and other changes in the preferred embodiment of the invention will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

We Claim:
1. A material handling bag for transporting material comprising:
• an operative bottom face;
• a plurality of side faces along with said operative bottom face configuring an enclosure provided with an open operative top for facilitating filling of said enclosure, wherein a first pair of opposite side faces are extending beyond a second pair of opposite side faces;
• a pair of tunnels configured from said first pair of opposite side faces, said tunnels adapted to receive tines of a fork of a fork lift truck, thereby facilitating suspending of said material handling bag on said fork, such that walls of said tunnels are extending above said top edges of said second pair of opposite side faces in the suspended configuration of the material handling bag;
• a plurality of loops disposed along the operative top edges of said side faces at four corners of said open operative top of said enclosure; and
• at-least some of said faces and said tunnels have strategically inherently disposed reinforced portions.
2. A material handling bag as claimed in claim 1, wherein said at-least some of said faces and said tunnels are configured from a U-panel.

3. A material handling bag as claimed in claim 1, wherein said strategically inherently disposed reinforced portions are configured during weaving.
4. A material handling bag as claimed in claim 1, wherein said strategically inherently disposed reinforced portions are configured by folding.
5. A material handling bag as claimed in claim 1, wherein strategically inherently disposed reinforced portions are reinforced with synthetic filaments.
6. A material handling bag as claimed in claim 1, wherein strategically inherently disposed reinforced portions are reinforced with natural filaments.
7. A material handling bag as claimed in claim 2, wherein said loops are configured from U panels.
8. A material handling bag as claimed in claim 2, wherein said strategically inherently disposed reinforced portions are disposed at edge portion of said U panels.
9. A material handling bag as claimed in claim 2, wherein said strategically inherently disposed reinforced portions are disposed at center portion of said U panels.
10. A material handling bag as claimed in claim 1, wherein said loops are integral to said material handling bag.
11. A material handling bag as claimed in claim 1, wherein said loops are additionally fitted to said material handling bag.

12. A material handling bag as claimed in claim 1, wherein an operative top end of each of said tunnel extends beyond said operative top edges of said side faces of said material handling bag.
13. A material handling bag as claimed in claim 1, wherein an operative top end of each of said loops extend beyond said operative top edges of said side faces of said material handling bag.