The closing of the transaction follows the completion of planned maintenance at the Bayport facility and satisfaction of regulatory and other customary closing conditions.
Rapier weaving machine
These machines can satisfactorily weave sheeting, flannels, drills, muslins, print cloths, etc and it can be extended to the weaving of carpets from continuous filament yarns. Textured filaments made from Taslan, untwisted filament and intermingled cotton and polyester covered core yarns and elastomeric yarns can be effectively woven on these machines. Heavy denier multifilament yarns can also be successfully used. PET with crepe twist or reinforced Lurex are both woven as weft without problems. Industrial fabrics, tyrecords, tents, screens, sail cloth tarpaulin, and glass fabric can also be woven.
Air-jet weaving machine
These machines have proved to be ideal for spun yarns. Recently it has been possible to weave a wider range of fabrics in spun as well as filament yarns and with up to six colours in weft or yarn counts. However, the yarn quality restricts the machine speed. Modem spinning mills are able to give better quality yarns. Modem warp preparation is crucial for today's weaving machines.
Water-jet weaving machine
This system has proved very useful in the case of synthetic filament yarns, which are hydrophobic. It is advantageous as compared with shuttle looms for bulk production of fabrics made of polyamides and other hydrophobic fibres. This machine is confined to only hydrophobic synthetic filament yarns. This is due to the problems associated with sizing, wet strength of hydrohphillic yarns and also the requirement of a perfectly clear warp shed.
Thus the machine is restricted to filamental warp yarns that do not require sizing and also do not lose strength on wetting. Normally weaves such crepe, matt, and twill are used, with yarn counts ranging between 10 - 120 denier. The warp/weft thread sett or density ranges between 25/25 and 360/240 per square inch and the maximum achievable areal density of the fabric is about 60zlsq yd. Since the construction of the weaving machine, specially, the sley, is light, heavier varieties of fabrics cannot be woven. There is a possibility to increase the weft set to 300 picks/inch. However, the maximum dents/inch in reed is only 76. If reeds of higher densities are used, there is problem of water clogging, which can create difficulties in shedding. The twist in warp yarns is minimum, about 7.5 tpi, as the yarn is unsized. Fabrics such as lingerie, ladies dresses, shirting, tent canvas and industrial fabrics can be successfully woven on these machines.
The overall quality of the fabric is below the expected level, which is mainly due to the problems concerned with the water jet weft insertion. These machines have the advantages of high speed and low noise. Also they are well suited for weaving of super fine continuous filament yarns. The effectiveness of the weft propulsion is mainly dependent on the wettability of the weft. The drag on hydrophobic filament yarn is much lesser than that on cotton yarns.
Generation of static charges is prevented due to the presence of water. It is crucial that the weft yarns do not contact the warp yarns during their insertion into the shed, as otherwise this could lead to fabric defects due to entanglement. Effectiveness of weft insertion requires the fluid jet to remain in contact with the weft and to move into the shed more quickly than the yarn. A major problem with hydraulic picking is the presence of partial of full double picks across the width of the fabric, which can arise due to a number of reasons.
Weaving with multifilament yarns
Multifilament yarns are used in the manufacture of apparels so as to get an excellent hand, drape, appearance, wrinkle resistance and easy care properties. The yarn are either used as single, or plied together with or without twist. The yarns are denoted as denier/number of constituent filaments/twist. Generally higher the number of filaments of equal denier, more fuller is the fabric. The yarns can be woven successfully on any of the following types of machines (Table 2) but certain modifications on looms are required for satisfactory weaving. It is desirable to weave the filament warp beams on better and sophisticated looms.
Machine alterations
Some of the suggested modifications on the weaving machine are as follows:
Chrome plated iron or highly polished wooden back rollers should be used.
Extended backrest should be preferred.
The number of heald shafts and the number of rows of drop pins should not have a common factor. Thus, for a plain weave on four shafts, three or five rows of drop pins should be used according to the number of ends in the warp. This procedure ensures that the ends from any given heald shaft are distributed over all rows of pins.
Sizes of drop wires
Suitable dimensions of drop wires are to be used (Table 3). Heald frames made of metal and having flat heald wires (with rectangular eyes) are recommended. The rectangular eyes of the heald wires have large area of contact, which reduces the pressure on length of yarn during shedding.
Shuttles made of laminated wood and having consistent size and weight are to be used. The eye of the shuttle should be padded and have ceramic pins. Low and uniform yarn tension are necessary for weft yarn during weaving. This can be achieved by using shuttle lined with fur or nylon loop strip. The distance between the pirn tip to the eye should be 12 - 30mm.
Sizes of heald wires
Reed made of metal with 60% air space and 10 cm depth is preferable
Box front should be smooth and preferably lined with fur.
Sley should be covered with corduroy fabrics, or velvet to reduce the damage that may take place due to frictional contact between the moving shuttles and the sley race board.
Warp tension should be enough just to get clear shed.
Photoelectric weft stop motion should be used.
Tipless shuttles should be used for high-speed looms
For filament weaving, it is important that the cloth take-up roller should hold the cloth firmly without slippage, but without causing any abrasion of the filaments. Emery roll should be covered with rubber fillet.
The direct take-up motion where the cloth is wound on the take-up roller directly is ideal as it ensures better control and avoids slippage of fabrics.
Circular disc or sun temples are ideal. Roller temples with rubber sleeves can be used. Ring temples with 2 or 3 rings are also used.
Part of the hammers coming in contact with the yarn should be lined with fur to prevent damage to filament.
Processing factors
The following recommendations are made for weaving of texturised as flat continuous filament yarns:
Back rest should be levelled with the breast beam or front rest and drop wire stand is aligned to give an even shedding.
Tension in the top and bottom levels of shed should be equalised as far as possible. Low warp tension, enough to get a clear shed opening, is preferable.
Weft tension should be set to minimum level enough, to prevent weft snarl or loopy selvedge (approximately 0.10 - 0.15 gpd). The difference in tension between the full and the empty pirn should not exceed 15g.
Late shedding by 150 or more for filament warp and normal for spun warps with filament weft-flat or texturised is recommended.
Selvedge should be about 15 mm wide for dress material and 20 mm wide for suiting.
Weaving of monofilament fabrics
Monofilaments are normally used both as warp and weft. However, in special applications, such as parachutes, conveyor belt linings, ski-anoraks, etc monofilaments are used in combination with multifilament yarns. There is no restriction in the warp yarn with regard to the thread density (sett) and yarn linear density. However, in the case of weft yarn the yarn linear density and cloth width are to be considered, since other conditions prevail for the monofilaments (l0 - 1000 dtex) as, for coarse monofilament wires (D 1 - 0.85 mm) in weft insertion, which are influenced by the stiffness of the monofilament itself. Depending on the fmal use polyester, polyamide, polypropylene, carbon fibres or PVC monofilaments or wires are used. Some of the applications of monofilament fabrics are bolting cloth, geo-textiles, filter fabrics, etc.
Conclusion
Weaving with synthetic filament yarns has now become possible on all types of shuttleless weaving machines with suitable modifications. It has become possible to weave wider denier range of yarns. Rapier weaving machines can effectively weave industrial fabrics, tyrecords, tents, screens, sailcloth tarpaulin, and glass fabrics. In the case of air-jet weaving machines, it has been possible to weave a wider range of fabrics in spun as well as filament yarns and with up to six colours in weft or yarn counts. However, the yarn quality restricts the machine speed. Modern spinning mills are able to give better quality yarns. Modern warp preparation is crucial for today's weaving machines. Multifilament yarns of varying denier can also be woven on projectile, rapier and air-jet weaving machines with certain modifications.
Rapier weaving machine
These machines can satisfactorily weave sheeting, flannels, drills, muslins, print cloths, etc and it can be extended to the weaving of carpets from continuous filament yarns. Textured filaments made from Taslan, untwisted filament and intermingled cotton and polyester covered core yarns and elastomeric yarns can be effectively woven on these machines. Heavy denier multifilament yarns can also be successfully used. PET with crepe twist or reinforced Lurex are both woven as weft without problems. Industrial fabrics, tyrecords, tents, screens, sail cloth tarpaulin, and glass fabric can also be woven.
Air-jet weaving machine
These machines have proved to be ideal for spun yarns. Recently it has been possible to weave a wider range of fabrics in spun as well as filament yarns and with up to six colours in weft or yarn counts. However, the yarn quality restricts the machine speed. Modem spinning mills are able to give better quality yarns. Modem warp preparation is crucial for today's weaving machines.
Water-jet weaving machine
This system has proved very useful in the case of synthetic filament yarns, which are hydrophobic. It is advantageous as compared with shuttle looms for bulk production of fabrics made of polyamides and other hydrophobic fibres. This machine is confined to only hydrophobic synthetic filament yarns. This is due to the problems associated with sizing, wet strength of hydrohphillic yarns and also the requirement of a perfectly clear warp shed.
Thus the machine is restricted to filamental warp yarns that do not require sizing and also do not lose strength on wetting. Normally weaves such crepe, matt, and twill are used, with yarn counts ranging between 10 - 120 denier. The warp/weft thread sett or density ranges between 25/25 and 360/240 per square inch and the maximum achievable areal density of the fabric is about 60zlsq yd. Since the construction of the weaving machine, specially, the sley, is light, heavier varieties of fabrics cannot be woven. There is a possibility to increase the weft set to 300 picks/inch. However, the maximum dents/inch in reed is only 76. If reeds of higher densities are used, there is problem of water clogging, which can create difficulties in shedding. The twist in warp yarns is minimum, about 7.5 tpi, as the yarn is unsized. Fabrics such as lingerie, ladies dresses, shirting, tent canvas and industrial fabrics can be successfully woven on these machines.
The overall quality of the fabric is below the expected level, which is mainly due to the problems concerned with the water jet weft insertion. These machines have the advantages of high speed and low noise. Also they are well suited for weaving of super fine continuous filament yarns. The effectiveness of the weft propulsion is mainly dependent on the wettability of the weft. The drag on hydrophobic filament yarn is much lesser than that on cotton yarns.
Generation of static charges is prevented due to the presence of water. It is crucial that the weft yarns do not contact the warp yarns during their insertion into the shed, as otherwise this could lead to fabric defects due to entanglement. Effectiveness of weft insertion requires the fluid jet to remain in contact with the weft and to move into the shed more quickly than the yarn. A major problem with hydraulic picking is the presence of partial of full double picks across the width of the fabric, which can arise due to a number of reasons.
Weaving with multifilament yarns
Multifilament yarns are used in the manufacture of apparels so as to get an excellent hand, drape, appearance, wrinkle resistance and easy care properties. The yarn are either used as single, or plied together with or without twist. The yarns are denoted as denier/number of constituent filaments/twist. Generally higher the number of filaments of equal denier, more fuller is the fabric. The yarns can be woven successfully on any of the following types of machines (Table 2) but certain modifications on looms are required for satisfactory weaving. It is desirable to weave the filament warp beams on better and sophisticated looms.
Machine alterations
Some of the suggested modifications on the weaving machine are as follows:
Chrome plated iron or highly polished wooden back rollers should be used.
Extended backrest should be preferred.
The number of heald shafts and the number of rows of drop pins should not have a common factor. Thus, for a plain weave on four shafts, three or five rows of drop pins should be used according to the number of ends in the warp. This procedure ensures that the ends from any given heald shaft are distributed over all rows of pins.
Sizes of drop wires
Suitable dimensions of drop wires are to be used (Table 3). Heald frames made of metal and having flat heald wires (with rectangular eyes) are recommended. The rectangular eyes of the heald wires have large area of contact, which reduces the pressure on length of yarn during shedding.
Shuttles made of laminated wood and having consistent size and weight are to be used. The eye of the shuttle should be padded and have ceramic pins. Low and uniform yarn tension are necessary for weft yarn during weaving. This can be achieved by using shuttle lined with fur or nylon loop strip. The distance between the pirn tip to the eye should be 12 - 30mm.
Sizes of heald wires
Reed made of metal with 60% air space and 10 cm depth is preferable
Box front should be smooth and preferably lined with fur.
Sley should be covered with corduroy fabrics, or velvet to reduce the damage that may take place due to frictional contact between the moving shuttles and the sley race board.
Warp tension should be enough just to get clear shed.
Photoelectric weft stop motion should be used.
Tipless shuttles should be used for high-speed looms
For filament weaving, it is important that the cloth take-up roller should hold the cloth firmly without slippage, but without causing any abrasion of the filaments. Emery roll should be covered with rubber fillet.
The direct take-up motion where the cloth is wound on the take-up roller directly is ideal as it ensures better control and avoids slippage of fabrics.
Circular disc or sun temples are ideal. Roller temples with rubber sleeves can be used. Ring temples with 2 or 3 rings are also used.
Part of the hammers coming in contact with the yarn should be lined with fur to prevent damage to filament.
Processing factors
The following recommendations are made for weaving of texturised as flat continuous filament yarns:
Back rest should be levelled with the breast beam or front rest and drop wire stand is aligned to give an even shedding.
Tension in the top and bottom levels of shed should be equalised as far as possible. Low warp tension, enough to get a clear shed opening, is preferable.
Weft tension should be set to minimum level enough, to prevent weft snarl or loopy selvedge (approximately 0.10 - 0.15 gpd). The difference in tension between the full and the empty pirn should not exceed 15g.
Late shedding by 150 or more for filament warp and normal for spun warps with filament weft-flat or texturised is recommended.
Selvedge should be about 15 mm wide for dress material and 20 mm wide for suiting.
Weaving of monofilament fabrics
Monofilaments are normally used both as warp and weft. However, in special applications, such as parachutes, conveyor belt linings, ski-anoraks, etc monofilaments are used in combination with multifilament yarns. There is no restriction in the warp yarn with regard to the thread density (sett) and yarn linear density. However, in the case of weft yarn the yarn linear density and cloth width are to be considered, since other conditions prevail for the monofilaments (l0 - 1000 dtex) as, for coarse monofilament wires (D 1 - 0.85 mm) in weft insertion, which are influenced by the stiffness of the monofilament itself. Depending on the fmal use polyester, polyamide, polypropylene, carbon fibres or PVC monofilaments or wires are used. Some of the applications of monofilament fabrics are bolting cloth, geo-textiles, filter fabrics, etc.
Conclusion
Weaving with synthetic filament yarns has now become possible on all types of shuttleless weaving machines with suitable modifications. It has become possible to weave wider denier range of yarns. Rapier weaving machines can effectively weave industrial fabrics, tyrecords, tents, screens, sailcloth tarpaulin, and glass fabrics. In the case of air-jet weaving machines, it has been possible to weave a wider range of fabrics in spun as well as filament yarns and with up to six colours in weft or yarn counts. However, the yarn quality restricts the machine speed. Modern spinning mills are able to give better quality yarns. Modern warp preparation is crucial for today's weaving machines. Multifilament yarns of varying denier can also be woven on projectile, rapier and air-jet weaving machines with certain modifications.
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