Claims:WE CLAIM:
1. A spinneret (100) comprising:
a plate (105) having an operative upstream surface (110) and an operative downstream surface (115);
a plurality of frusto-conical nozzles (125) configured on said operative downstream surface (115), said nozzles (125) communicating with a plurality of openings (120) configured on the operative upstream surface (110), each nozzle (125) terminating in a flat tip (130) defining an outlet.
2. The spinneret (100) as claimed in claim 1, wherein the ratio of difference between radii of an inner edge (130a) and an outer edge (130b) of said flat tip (130) to the radius of said inner edge (130a) of said flat tip (130) ranges from 0.1 to 3.33.
3. The spinneret (100) as claimed in claim 2, wherein the radius of said inner edge (130a) ranges from 0.06 mm to 0.5 mm.
4. The spinneret (100) as claimed in claim 2, wherein difference between said radii of said inner edge (130a) and said outer edge (130b) of said flat tip (130) ranges from 0.05 mm to 0.2 mm.
5. The spinneret (100) as claimed in claim 1, wherein the ratio of the diameter of a base portion to height of each of said plurality of frusto-conical nozzles (125) ranges from 1 to 3.75.
6. The spinneret (100) as claimed in claim 5, wherein the ratio of the diameter of said base portion to the diameter of an inner edge (130a) of said flat tip (130) ranges from 2.5 to 37.5.
7. The spinneret (100) as claimed in claim 5, wherein the diameter of said base portion ranges from 2.5 mm to 4.5 mm.
8. The spinneret (100) as claimed in claim 1, wherein the height of each of said plurality of frusto-conical nozzles (125) ranges from 1.2 mm to 2.5 mm.
9. The spinneret (100) as claimed in claim 1, wherein said plurality of frusto-conical nozzles (125) is made integral with said plate (105).
, Description:FIELD
The present disclosure relates to the field of spinnerets.
DEFINITIONS
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicate otherwise.
Frusto-conical nozzle – The term “frusto-conical nozzle” hereinafter in the complete specification refers to a nozzle having a shape of a frustum of a cone.
BACKGROUND
A conventional spinneret has a spinneret body having a plurality of holes configured thereon. Softened polymer is forced through the plurality of holes to form filaments of the polymer. While oozing out from the spinneret plate, the polymer filament swells due to release of stored elastic energy. A portion of the swelled filament touches and sticks to an operative downstream surface of the spinneret plate. Over a period of time, the portion stuck to the spinneret plate starts accumulating on the operative downstream surface and further decomposes. The rate of decomposition accelerates in presence of oxygen. Due to gravity pull, the accumulated portion of the filament gets released from the operative downstream surface of the spinneret, and sticks to the filament being spun. This results in breaking of the filament at a drawing zone or a neckline region, which is not desirable. The breaking of the filament stops entire spinning process.
Conventionally, wiping operation is performed on the operative downstream surface of the spinneret to remove the accumulated portion of the filament. During the wiping operation, the accumulated portion of the filament is removed using a silicon oil and a wiper having brass blades. Typically, the wiping operation needs to be performed after every 48 hours or 72 hours. Such frequent need of the wiping operation reduces production of the polymer filaments as the spinneret remains idle during the wiping operation. Further, the silicon oil is costly which results in increased manufacturing cost of the filaments.
Therefore, there is felt a need of a spinneret that alleviates the aforementioned drawbacks of conventional spinnerets.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
An object of the present disclosure is to provide a spinneret that facilitates increase in production of the polymer filaments.
Another object of the present disclosure is to provide a spinneret that facilitates reduction in breakage of filaments.
Yet another object of the present disclosure is to provide a spinneret that facilitates reduction in frequency of wiping operation.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure envisages a spinneret. The spinneret comprises a plate, and a plurality of frusto-conical nozzles. The plate has an operative upstream surface and an operative downstream surface. The plurality of frusto-conical nozzles is configured on the operative downstream surface of the plate. The nozzles communicate with a plurality of openings configured on the operative upstream surface of the plate. Each nozzle terminates in a flat tip that defines an outlet.
In an embodiment, the ratio of difference between radii of an inner edge and an outer edge of the flat tip to the radius of the inner edge of the flat tip ranges from 0.1 to 3.33. In another embodiment, the difference between radii of the inner edge and the outer edge of the flat tip ranges from 0.05 mm to 0.2 mm.
In another embodiment, the ratio of the diameter of a base portion to height of each of the plurality of frusto-conical nozzles ranges from 1 to 3.75. Further, the ratio of the diameter of the base portion to the diameter of the inner edge of the flat tip ranges from 2.5 to 37.5.
The plurality of the frusto-conical nozzles is made integral with the plate.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
A spinneret of the present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates an isometric view of a spinneret, in accordance with an embodiment of the present disclosure;
Figure 2 illustrates another isometric view of the spinneret of figure 1;
Figure 3 illustrates a front view of the spinneret of figure 1;
Figure 4 illustrates a schematic sectional enlarged view depicting a nozzle of the spinneret of figure 1 and a swelled filament; and
Figure 5 illustrates a schematic sectional view of an opening and a nozzle of the spinneret of figure 1.
LIST OF REFERENCE NUMERALS
100 – Spinneret
105 – Plate
110 – Upstream surface
115 – Downstream surface
120 – Openings
125 – Nozzle
130 – Flat tip of the nozzle
130a – Inner edge of the flat tip
130b – Outer edge of the flat tip
135 – Bulged filament
140 – Capillary
DETAILED DESCRIPTION
The present disclosure envisages a spinneret that reduces breakage of filaments in a spinning process, and increases production of polymer filaments.
The spinneret, of the present disclosure, is now described with reference to figure 1 through figure 5. Figure 1 illustrates an isometric view of a spinneret 100, in accordance with an embodiment of the present disclosure. Figure 2 illustrates another isometric view of the spinneret 100. Figure 3 illustrates a front view of the spinneret 100. Figure 4 illustrates a schematic sectional enlarged view depicting a nozzle of the spinneret 100 and a swelled filament. Figure 5 illustrates a schematic sectional view of an opening and a nozzle of the spinneret 100.
The spinneret 100 comprises a plate 105. The plate 105 has an operative upstream surface 110 and an operative downstream surface 115. A plurality of openings 120 is configured on the operative upstream surface 110. The openings 120 extend from the operative upstream surface 110 to the operative downstream surface 115 to provide a passage to softened polymer being spun. The softened polymer is forced to pass through the openings 120 from the operative upstream surface 110 of the plate 105. Typically, the diameter of each of the openings 120 ranges from 1 mm to 3 mm. In an embodiment, the diameter of each of the openings 120 is 3 mm.
The spinneret 100 further comprises a plurality of frusto-conical nozzles 125 configured on the operative downstream surface 115. The nozzles 125 communicate with the plurality of openings 120. Each nozzle 125 terminates in a flat tip 130 defining an outlet. The softened polymer emanates out from the flat tip 130 in the form of a plurality of filaments. An opening is provided on the flat tip 130 of each of the nozzles 125 to facilitate exiting of the plurality of filaments. Further, the frusto-conical nozzle 125 has a base portion configured on the operative downstream surface 115 of the plate 105.
The dimensions of each of the nozzles 125 are determined as per the dimensions of the openings 120 and the size of the plurality of polymer filaments.
The surface area of the flat tip 130 of each of the nozzles 125 is determined in such a way that minimum surface contact area is available for the filaments exiting through the flat tip 130. The minimum surface area of the flat tip 130 prevents touching and sticking of a portion of bulged filament exiting through the flat tip 130.
The flat tip 130 is defined by an inner edge 130a and an outer edge 130b. The opening on the flat tip 130 defines a capillary 140. In an embodiment, the ratio of the difference between radii of the inner edge 130a and the outer edge 130b of the flat tip 130 to the radius of the inner edge 130a of the flat tip 130 ranges from 0.1 to 3.33. The radius of the inner edge 130a of the flat tip 130 ranges from 0.06 mm to 0.5 mm. The diameter of the outer edge 130b of the flat tip 130 is selected such that the wall thickness of each of the nozzles 125 remains in the range of 0.05 mm to 0.2 mm. The difference between radii of the inner edge 130a and the outer edge 130b of the flat tip 130 ranges from 0.05 mm to 0.2 mm. More specifically, the radius of the outer edge 130b of the flat tip 130 is 0.05 mm to 0.2 mm more than the radius of the inner edge 130a of the flat tip 130.
In another embodiment, the ratio of the diameter of the base portion to height of each of the plurality of nozzles 125 ranges from 1 to 3.75. Typically, the diameter of the base portion of each of the nozzles 125 ranges from 2.5 mm to 4.5 mm. In an embodiment, the height of each of nozzles 125 ranges from 1.2 mm to 2.5 mm.
In yet another embodiment, the wall thickness of each of the nozzles 125 ranges from 0.05 mm to 0.2 mm.
In another embodiment, the ratio of the diameter of the base portion to the diameter of the inner edge 130a of the flat tip 130 ranges from 2.5 to 37.5.
The plurality of frusto-conical nozzles 125 can be configured on the operative downstream surface 115 of the plate 105 using any suitable method. Typically, the nozzles 125 are configured on the operative downstream surface 115 of the plate 105 using CNC milling method or punching. In an embodiment, the plurality of frusto-conical nozzles 125 is made integral with the plate 105.
The softened polymer is forced through the plurality of openings 120 from the operative upstream surface 110 of the plate 105. The plurality of filaments is formed when the softened polymer emanates out of the plate 105 from the flat tip 130 of the nozzles 125. The polymer has visco-elastic properties. When the polymer passes through the openings 120, the polymer gains elastic energy. When the filaments of the polymer emanates out from the flat tip 130, there is an increase in the diameter of the filaments due to release of the stored elastic energy. This increase in the diameter of the filaments results in formation of bulged filaments 135 as shown in figure 4. However, minimum surface area is available at the flat tip 130. Thus, a portion of bulged filament 135 does not stick to the surface of the flat tip 130. Therefore, subsequent decomposition of the portion of the bulged filament 135 is avoided, thereby preventing breakage of the filament at a neckline or a drawing zone.
The spinneret 100 and a conventional spinneret (without nozzles) were tested for determining the hours of operation upto which the spinnerets can operate without filament breakage. Both the spinnerets were tested under identical conditions. It was observed that the conventional spinneret was operational for 48 hours before first filament breakage was observed. On the other hand, the spinneret 100 was operational for 13 days before first filament breakage was observed.
As the frequency of filament breakage is reduced, the spinneret 100 facilitates increase in production of the polymer filaments. It was observed that production of the polymer filaments was increased by 0.3% due to use of the spinneret 100.
Further, the spinneret 100 also reduces the frequency of wiping operation as the frequency of filament breakage is reduced. The reduction in frequency of the wiping operation results in reduction in operational cost as less silicon oil is consumed.
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a spinneret that facilitates:
• increase in production of polymer filaments;
• reduction in breakage of filaments; and
• reduction in frequency of wiping operation.
The foregoing disclosure has been described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. 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 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.
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 disclosure 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 disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure 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 disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure 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 disclosure and not as a limitation.