DESC:TECHNICAL FIELD
[1] The present disclosure relates, in general, to a manufacturing process of nets. In particular, the present disclosure relates to a process of joining net panels for manufacturing aquaculture cages.

BACKGROUND
[2] Aquaculture net cages and predator net panels are like closed boxes, which are used to grow fish in the sea and protect them from different kinds of predators. In the aquaculture industry, most fish farmers use knotless nets for the cages, typically made using nylon material such as braided nylon netting for predator net panels.
[3] Using high density polyethylene (HDPE) material for nets is advantageous and provides features such as,
• higher cut resistance;
• higher abrasion resistance due to compactness, which results in longer operating life;
• lower shrinkage, which results in greater dimensional stability and less load on structure;
• better braided twine geometry and stiffness, which results in better shape retention;
• minimum loss of strength in water due to hydrophobic nature of the material; and
• monofilament compactness of twine structure, which result in less open space for fouling attachment.
[4] Additionally, using knotted nets with HDPE material is advantageous, and provides features such as, longer operating life since use of knots reduces net tearing.
[5] However, present art does not provide an adequate means to manufacture such nets without fully realizing the advantages as listed for the nets.
[6] There is, therefore, a requirement in the art for an approach for manufacturing HDPE knotted net structure.
OBJECTS OF THE PRESENT DISCLOSURE
[7] A general objective of the present disclosure relates, in general, to a manufacturing process of nets. In particular, the present disclosure relates to a process of joining net panels for manufacturing aquaculture cages.
[8] An objective of the present disclosure is to provide an aquaculture cage that have rigid joints with uniform mesh size.
[9] Another objective of the present disclosure is to provide an aquaculture cage with firmly locked half legs of both net panels.
[10] Another objective of the present disclosure is to provide an aquaculture cage that has aesthetic appearance of the net joint, which may not be easily identified by the predators, thereby preventing attack on the net joint.
[11] Another objective of the present disclosure is to provide an aquaculture cage that provides tight knots and a firm square mesh.
[12] Another objective of the present disclosure is to provide an aquaculture cage with knots that may not slip easily.
[13] Another objective of the present disclosure is to provide an aquaculture cage with selvedge having same breaking strength as the net panels.
[14] Another objective of the present disclosure provides an aquaculture cage that provides longer operating life since use of knots reduces net tearing.
[15] Yet another objective of the present disclosure seals twine ends of the net, which avoids unravelling of twine and opening of the mesh.

BRIEF DESCRIPTION OF DRAWINGS
[16] The accompanying drawings are included to provide further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure. The diagrams are for illustration only, which thus is not a limitation of the present disclosure.
[17] FIGs. 1A and 1B illustrate exemplary representations of a net, where two net panels have been joined using a bale-to-bale joining approach, in accordance with an embodiment of the present disclosure.
[18] FIGs. 2A and 2B illustrate representations of a net, where selvedge of two net panels have been joined using a conventional joining approach.
[19] FIGs. 2C and 2D illustrate exemplary representations of a net, where selvedge of two net panels have been joined using an MD joining approach, in accordance with an embodiment of the present disclosure.
[20] FIG. 3 illustrates an exemplary representation of a process for knot tightening, in accordance with an embodiment of the present disclosure.
[21] FIGs. 4A – 4C illustrate exemplary representations of a process for heat sealing and cutting of net panel, in accordance with an embodiment of the present disclosure.
[22] FIG. 5 illustrates an exemplary flow diagram of a method for manufacturing an aquaculture net cage, in accordance with an embodiment of the present disclosure.

SUMMARY
[23] The present disclosure relates, in general, to a manufacturing process of nets. In particular, the present disclosure relates to a process of joining net panels for manufacturing aquaculture cages.
[24] In an aspect, the present disclosure provides a method of manufacturing an aquaculture net cage, the method including joining twines of two or more net panels to form knots, said two or more net panels comprising a plurality of linked meshes composed of twines, wherein the knots are formed by any or a combination of bale-to-bale joint and mesh depth (MD) joint, stretching, by a stretching mechanism, joined part of two nets to be fixed on knot tightening table, stretched enough to tighten knots mechanically and apply steam on all knots made by hand, the steam is supplied from a heating source and sealing, by a heating and cutting mechanism, the twine ends of the two or more net panels to avoid any or a combination of unravelling of twines and opening of the plurality of linked meshes.
[25] According to an embodiment, same nets are joined by MD joint and different nets are joined by bale-to-bale joint, wherein joining of any or a combination of same and different nets are performed using same net body twine/twine which is higher in strength than net body twine, wherein the same nets are joined with single knot or double knot, wherein the joining twine can be made of material such as Nylon, Polyolifines, Polyester and any combination thereof.
[26] According to an embodiment, the knots are tighten using steam, super-heated steam, hot water, hot air, knot tightening/bonding material and any combination thereof.
[27] According to an embodiment, application of hot air on the nets enables a smooth finish and removes protruding fibres from the twine ends.
[28] According to an embodiment, the stretching mechanism can include lead screw, hydraulic, pneumatic power packs and any combination thereof.
[29] According to an embodiment, the stretching of the nets is performed in the ratio of 0.1 to 10 %.
[30] According to an embodiment, the sealing of twine ends by the heating and cutting mechanism can include hot knife, hot air gun and any combination thereof.
[31] According to an embodiment, the two or more net panels are joined at selvedge using MD joining approach, wherein different coloured twine used to join the two or more nets panels at selvedge.
[32] According to an embodiment, the same coloured twine used to join the two or more net panels at the selvedge.
[33] In an aspect, the present disclosure provides a aquaculture net cage including two or more net panels comprising a plurality of linked meshes composed of twines, wherein the twines of the two or more net panels are joined to form knots, the knots are formed by any or a combination of bale-to-bale joint and MD joint, a stretching mechanism configured to stretch joined part of two nets to be fixed on knot tightening table, stretched enough to tighten knots mechanically and apply steam on all knots made by hand, the steam is supplied from a heating source, and a heating and cutting mechanism configured to seal twine ends of the two or more net panels to avoid unravelling of twines and opening of the plurality of linked meshes.
[34] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

DETAILED DESCRIPTION
[35] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[36] The present disclosure relates, in general, to a manufacturing process of nets. In particular, the present disclosure relates to a process of joining net panels for manufacturing aquaculture cages. The present disclosure provides an approach to manufacture a net that has a uniform net size and where half legs of two or more net panels can be joined firmly and rigidly. The present disclosure can be described in enabling detail in the following examples, which may represent more than one embodiment of the present disclosure.
[37] FIGs. 1A and 1B illustrate exemplary representations of a net, where two net panels have been joined using a bale-to-bale joining approach, in accordance with an embodiment of the present disclosure.
[38] Referring to FIG. 1A and FIG. 1B, aquaculture net cage 100 can be configured to raise aquatic life such as fish. The aquaculture net cage 100 can include two or more net panels (102, 104), where the two or more net panels (102, 104) can include linked meshes composed of twines. The twines of two or more net panels (102, 104) are joined to form knots. The aquaculture net cage 100 keeps the aquatic life controlled and protects the aquatic life inside net against predators such as sharks, piranhas, nutrias, seals, sea lions and the likes
[39] In an exemplary embodiment, the knots formed by any or a combination of bale-to-bale joint and mesh depth (MD) joint. The different net panels joined by the bale-to-bale joining approach using the same body twine and the knot tightening processing can be performed. The same net panels joined by MD joint approach using the same body twine and the knot tightening processing can be performed.
[40] The joining of any or a combination of same and different nets of the net panels are performed using same net body twine or twine which is higher in strength than the net body twine of the net panels, where the same nets are joined with single knot or double knot. The joining twine can be made of any material such as Nylon, Polyolifines, Polyester and any combination thereof.
[41] The knot tightening processing can be performed using a stretching mechanism 302 and a heating source 304 illustrated in FIG. 3. The stretching mechanism 302 is configured to stretch the nets on a table/knot tightening table to supply steam to the knots to tighten the knots. The stretching of the nets can be performed in the ratio of 0.1 to 10 %. In an exemplary embodiment, the stretching mechanism 302 can be lead screw, hydraulic, pneumatic power packs and any combination thereof.
[42] The joined part of two nets or nets to be fixed on knot tightening table, stretched enough to tighten knots mechanically first and then apply steam on all knots made by hand. The steam is supplied from the heating source 304 to tighten the knots. The knots tighten using steam, superheated steam, hot water, hot air, any means of heating, knot tightening/bonding material and any combination thereof. The application of hot air on the nets enables a smooth finish and removes protruding end/fibres from the twine ends.
[43] According to an embodiment, a heating and cutting mechanism 402 as shown in FIG. 4A configured to seal twine ends of the two or more net panels (102, 104) to avoid opening of the linked meshes. In an exemplary embodiment, the heating and cutting mechanism 402 can include a hot knife, hot air gun and any combination thereof.
[44] In an exemplary embodiment, the two net panels (102, 104) have been joined using the bale-to-bale joining approach. In an embodiment, the net is manufactured by joining two net panels (102, 104) using same twine of the body of the net 100. Using “back and forth” knot on each knot of joint of the two net panels (102, 104), the joint can become firm and have a uniform mesh size. Additional nylon twine 106 can be used to make the knots tighter.
[45] In an exemplary embodiment, to make the joint rigid and to lock half legs of the bar, a black nylon twisted pre-shrunk twine 106 is used. The net can have the following features as follows:
• rigid joints with uniform mesh size;
• firmly locked half legs of both net panels (102, 104); and
• aesthetic appearance of the net joint, which will allow the net joint to be not easily identify, thereby preventing attack on the net joint.
[46] FIGs. 2A and 2B illustrate representations of a net, where selvedge of two net panels have been joined using a conventional joining approach. Conventionally, net lofts use nylon twine to join two selvedge meshes of two different net panels (202, 204). This can result in uneven square mesh, and it may also get hooked to material such as debris. This enables the joints to be easily recognisable to predators, which may try to attack the joint.
[47] FIGs. 2C and 2D illustrate exemplary representations of a net, where selvedge of two net panels have been joined using an MD joining approach, in accordance with an embodiment of the present disclosure. In this approach, a same knotting process as used in fishnet m/c knots is used to join the two net panels (252, 254) at selvedge. This maintains the mesh size uniform, and the predators cannot identify the joints easily.
[48] Referring to FIG. 2C, in one embodiment, a different coloured twine can be used to join the two net panels (252, 254) at the selvedge.
[49] Referring to FIG. 2D, in another embodiment, a same coloured twine as the net body can be used to join the two net panels (252, 254) at the selvedge.
[50] The net can have the following features as follows:
• selvedge with same strength as the net panels (252, 254);
• rigid joints with uniform mesh size; and
• aesthetic appearance of the net joint, which will allow the net joint to be not easily identify, thereby preventing attack on the net joint.
[51] FIG. 3 illustrates an exemplary representation of a process for knot tightening, in accordance with an embodiment of the present disclosure. Once the net panels (252, 254) are joined at selvedge using MD joining, the knots are tightened using steam. The process can be implemented on the table with the mechanism to stretch the net, and where, while being stretched, steam is supplied to the net, which results in tightening of the knots.
[52] The stretching mechanism 302 as illustrated in FIG. 3 configured to stretch the nets on the table to supply steam to the knots to tighten the knots, the steam is supplied from the heating source 304. The stretching of the nets can be performed in the ratio of 0.1 to 10 %. In an exemplary embodiment, the stretching mechanism 302 can include lead screw, hydraulic, pneumatic power packs and any combination thereof. The knots are tighten using steam, super-heated steam, hot water, hot air, knot tightening/bonding material and any combination thereof.
[53] The net can have the following features as follows:
• tight knots and a firm square mesh;
• uniform mesh size;
• knots that will not slip easily;
• selvedge with same breaking strength as the net panels (252, 254); and
• aesthetic appearance of the net joint, which will allow the net joint to be not easily identify, thereby preventing attack on the net joint.
[54] FIGs. 4A – 4C illustrate exemplary representations of a process for heat sealing and cutting of net panel, in accordance with an embodiment of the present disclosure. It is important to keep twine ends of a net sealed by heating them, which avoids unravelling of twine and opening of the mesh. Net panels for predator nets further can include a metal wire core.
[55] Conventionally, the twine is cut by a knife, and the ends are sealed using a flame gun, which can be dangerous.
[56] In an embodiment, the process of the present disclosure can involve use of heating and cutting mechanism 402 i.e., hot cutting knife/hot knife (refer FIG. 4A) to heat seal twine ends, and then cutting the metal wire using a metal wire cutter 404 (refer FIG. 4B). The sealed twine ends so obtained can be as illustrated in FIG. 4C.
[57] FIG. 5 illustrates an exemplary flow diagram of a method for manufacturing an aquaculture net cage, in accordance with an embodiment of the present disclosure.
[58] Referring to FIG. 5, at block 502, twines of two or more net panels can be joined to form knots, the two or more net panels can include linked meshes composed of twines, wherein the knots are formed by any or a combination of bale-to-bale joint and MD joint.
[59] At block 504, the stretching mechanism can stretch joined part of two nets to be fixed on knot tightening table, stretched enough to tighten knots mechanically and apply steam on all knots made by hand. The steam is supplied from the heating source. The stretching mechanism can include lead screw, hydraulic, pneumatic power packs and any combination thereof. The stretching of the nets can be performed in the ratio of 0.1 to 10 %. The knots are tighten using steam, superheated steam, hot water, hot air and any combination thereof.
[60] At block 506, the heating and cutting mechanism can seal the twine ends of the two or more net panels to avoid unravelling of twines and opening of the linked meshes. The heating and cutting mechanism can include hot knife, hot air gun and any combination thereof.
[61] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE PRESENT DISCLOSURE
[62] The present disclosure provides an aquaculture cage that have rigid joints with uniform mesh size.
[63] The present disclosure provides an aquaculture cage with firmly locked half legs of both net panels.
[64] The present disclosure provides an aquaculture cage that has aesthetic appearance of the net joint, which may not be easily identified by the predators, thereby preventing attack on the net joint.
[65] The present disclosure provides an aquaculture cage that provides tight knots and a firm square mesh.
[66] The present disclosure provides an aquaculture cage with knots that may not slip easily.
[67] The present disclosure provides an aquaculture cage with selvedge having same breaking strength as the net panels.
[68] The present disclosure provides an aquaculture cage that provides longer operating life since use of knots reduces net tearing.
[69] The present disclosure seals twine ends of the net, which avoids unravelling of twine and opening of the mesh.
,CLAIMS:1. A method (500) of manufacturing an aquaculture net cage, the method comprising:
joining (502) twines of two or more net panels to form knots, said two or more net panels comprising a plurality of linked meshes composed of twines, wherein the knots are formed by any or a combination of bale-to-bale joint and mesh depth (MD) joint;
stretching (504), by a stretching mechanism, joined part of at least two nets to be fixed on knot tightening table, stretched enough to tighten knots mechanically and apply steam on all knots made by hand, the steam is supplied from a heating source; and
sealing (506), by a heating and cutting mechanism, the twine ends of the two or more net panels to avoid any or a combination of unravelling of twines and opening of the plurality of linked meshes.
2. The method as claimed in claim 1, wherein same nets are joined by MD joint and different nets are joined by bale-to-bale joint, wherein joining of any or a combination of same and different nets are performed using same net body twine/twine which is higher in strength than net body twine, wherein the same nets are joined with single knot or double knot, wherein the joining twine is made of any material such as Nylon, Polyolifines, Polyester and any combination thereof.
3. The method as claimed in claim 1, wherein said knots are tighten using steam, super-heated steam, hot water, hot air, knot tightening/bonding material and any combination thereof.
4. The method as claimed in claim 3, wherein application of hot air on the nets enables a smooth finish and removes protruding fibres from the twine ends.
5. The method as claimed in claim 1, wherein said stretching mechanism (302) comprises lead screw, hydraulic, pneumatic power packs and any combination thereof.
6. The method as claimed in claim 5, wherein the stretching of the nets is performed in the ratio of 0.1 to 10 %.
7. The method as claimed in claim 1, wherein the sealing of twine ends by the heating and cutting mechanism (402) comprises hot knife, hot air gun and any combination thereof.
8. The method as claimed in claim 1, wherein said two or more net panels are joined at selvedge using MD joining approach, wherein different coloured twine (256) used to join the two or more nets panels at selvedge.
9. The method as claimed in claim 1, wherein the same coloured twine (256) used to join the two or more net panels at the selvedge.
10. An aquaculture net cage (100) comprising:
two or more net panels (102, 104) comprising a plurality of linked meshes composed of twines, wherein the twines of the two or more net panels (102, 104) are joined to form knots, the knots are formed by any or a combination of bale-to-bale joint and MD joint;
a stretching mechanism (302) configured to stretch joined part of at least two nets to be fixed on knot tightening table, stretched enough to tighten knots mechanically and apply steam on all knots made by hand, the steam is supplied from a heating source; and
a heating and cutting mechanism (402) configured to seal twine ends of the two or more net panels (102, 104) to avoid unravelling of twines and opening of the plurality of linked meshes.