METHOD AND INSTALLATION FOR PRODUCING A TWISTED SYNTHETIC YARN

Abstract

A method and an installation for producing a twisted synthetic yarn, comprising a spin-drawing installation configured to produce continuous filaments from a liquid plastics material or granular material by at least one spinneret and then to produce at least one yarn from at least two continuous filaments. A downstream treatment apparatus treats the at least one yarn which is transferred, without interruption, from the treatment apparatus to a downstream twisting/cabling apparatus via a collection and transport apparatus in a continuous process from the spin-drawing installation to the twisting/cabling apparatus. The collection and transport apparatus is configured to compensate for a difference in a production speed between the spin-drawing installation and the twisting/cabling apparatus.

Claims

1. A method for producing a twisted or cabled synthetic yarn, comprising the steps of: producing with at least one spinneret in a spin-drawing installation continuous filaments from a liquid plastics material or granular material and then producing at least one yarn from at least two continuous filaments; inputting the at least one yarn into a treatment apparatus; transferring the yarn from the treatment apparatus, without interruption, to a twisting/cabling apparatus, via a collection and transport apparatus; and buffering a predetermined length of the at least one yarn in the collection and transport apparatus in order to compensate for a production difference between the spin-drawing installation and the twisting/cabling apparatus.

2. (canceled)

3. The method according to claim 1, wherein the transferring step includes transferring at least two yarns by the collection and transport apparatus from the spin-drawing installation to the twisting/cabling apparatus.

4. The method according to claim 1, wherein the transferring step includes transferring at least two yarns from the treatment apparatus to a delivery apparatus for relaxing and transferring the at least two yarns in a form of a yarn or a plurality of yarns on the collection and transport apparatus to the twisting/cable apparatus.

5. The method according to claim 1, including treating the at least one yarn in an atmosphere of hot steam or conditioned gas while the at least one yarn is transferred from the spin-drawing installation to the twisting/cabling apparatus.

6. The method according to claim 1, including guiding the at least one yarn out of the spin-drawing installation at a speed of from 10 m/min to 600 m/min.

7. The method according to claim 1, including inputting the at least one yarn into the twisting/cabling apparatus at a speed of from 10 m/min to 500 m/min.

8. The method according to claim 1, further including the at least one yarn guided inside the collection and transport apparatus by one of a temperature-controlled drum, cylinders or rows of deflection rollers.

9. The method according to claim 1, wherein the delivering step includes relaxing the at least one yarn by a delivery apparatus including at least one transport roller assisted by steam of or conditioned gas.

10. The method according to claim 4, including using a controller for adapting a production speed of each of the delivery apparatus, and the twisting/cabling apparatus to a current buffer capacity of the collection and transport apparatus, and vice versa.

11. An installation for producing a twisted or cabled synthetic yarn, comprising: a spin-drawing installation including at least one spinneret configured to produce continuous filaments from a liquid plastics material or granular material by the at least one spinneret and then to produce at least one yarn from at least two continuous filaments; a treatment apparatus downstream of the spin-drawing installation for treating the at least one yarn; a collection and transport apparatus; and a twisting/cabling apparatus downstream of the collection and transport apparatus; wherein the installation is configured to transfer the at least one yarn without interruption from the spin-drawing installation to the twisting/cabling apparatus; and wherein the collection and transport apparatus is configured to compensate for a difference in a production speed between the spin-drawing installation and the twisting/cabling apparatus.

12. The installation according to claim 11, further including a delivery apparatus to deliver the at least one yarn from the treatment apparatus.

13. (canceled)

14. The installation according to claim 11, wherein the collection and transport apparatus comprises a revolving belt.

15. The installation according to claim 11, wherein the collection and transport apparatus comprises a drum including a thread guide.

16. The installation according to claim 11, wherein the collection and transport apparatus comprises adjustable cylinders to adjust a distance from one another.

17. The installation according to claim 11, wherein the collection and transport apparatus comprises an adjustable buffer including two rows of deflection rollers with a distance between the rows that is adjustable.

18. The installation according to claim 11 further including a housing in which collection and transport apparatus is arranged and which is configured to be filled with hot steam or conditioned gas.

19. The installation according to claim 11, further including a controller configured to adapt a production speed of the spin-drawing installation and of the twisting/cabling apparatus to a current buffer capacity of the collection and transport apparatus, or to reconcile a difference between a production speed of the spin-drawing installation and of the twisting/cabling apparatus.

20. The installation according to claim 19, wherein the controller is part of a system as a whole consisting of the spin-drawing installation and of the collection and transport apparatus.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Further measures enhancing the invention are described in detail below together with the description of a preferred exemplary embodiment of the invention, with reference to the figures, in which:

[0033] FIG. 1 shows a schematic representation of the installation for producing a synthetic yarn up to further processing in a twisting apparatus/cabling apparatus;

[0034] FIG. 2 shows a schematic top view of a first embodiment of a collection and transport apparatus in the form of a revolving belt;

[0035] FIG. 3 shows a schematic top view of a further embodiment of a collection and transport apparatus in the form of a drum;

[0036] FIG. 4 shows a schematic top view of a further embodiment of a collection and transport apparatus in the form of a buffer having two drums;

[0037] FIG. 5 shows a schematic top view of a further embodiment of a collection and transport apparatus in the form of a buffer having a plurality of deflections.

DETAILED DESCRIPTION

[0038] The installation according to the invention and the method are explained below with reference to FIGS. 1 to 5. Identical features in the drawing are in each case provided with identical reference signs. It will be appreciated at this point that the drawings are merely shown in simplified form and especially are not to scale.

[0039] In a first embodiment, a mixer 1 is configured to thoroughly mix a melt container 2 filled with solid plastics particles. The plastics particles are usually supplied in the form of chips and are introduced on their own or together with chips of a different type of plastics material into the melt container 2, where they are melted by means of energy input to form liquid plastics material. The mixer 1 ensures continuous thorough mixing of the plastics material, which in this method step varies in terms of its state of aggregation between solid and liquid (granules and solution). From the melt container 2, the liquid plastics material is guided via a pipeline to a spinning beam 5.

[0040] Alternatively, the plastics particles can be guided from silos via a supply device 3 to an extruder 4, which by means of energy input and pressure converts the solid plastics particles into a liquid plastics material and guides the liquid plastics material by means of a pipeline to the spinning beam 5 of a spin-drawing installation. Polypropylene, PA6, PA6.6, PET, PTT or other materials can be used as the plastics material. The materials can be improved in terms of their desired properties with a heat stabiliser, dyes, titanium dioxide, a UV stabiliser or other additives. The additives can be added continuously or can be mixed in with the raw materials.

[0041] The two methods can be used as alternatives. They have different advantages and disadvantages, but these are not relevant to the invention.

[0042] Inside the spinning beam 5 there is arranged at least one spinning pump 6 by means of which the liquid plastics material is pressed into and through the spinneret 7, which has a large number of small openings. Depending on the form of the spinneret 7, it can have a small number of openings, preferably at least two or also, for example, from 50 to 60, or a large number of up to more than 1000 openings. The spinneret 7 is connected to a heater 8 so as to avoid freezing of the plastics material. A continuous filament E flows through each opening of the spinneret 7, all of the continuous filaments passing through the shaft-like blow shaft 9 beneath the spinneret 7 having the heater 8, whereby the pasty molecular structure of the plastics material is consolidated for the first time. Beneath the blow shaft 9, additional cooling air is introduced into the blow shaft 9 via a drop pipe 10. In the blow shaft 9, the cooling molecular structure of the continuous filaments E is influenced via the amount of cooling air, the temperature and the relative humidity.

[0043] Subsequently, at least one yarn G is produced from at least two continuous filaments E, but preferably from a greater plurality of continuous filaments, and is guided via a first godet 11 to a treatment apparatus 12. Each yarn G preferably consists of at least two continuous filaments E.

[0044] The treatment apparatus 12 can have a plurality of heated or cooled godets, by means of which the yarn G is drawn. The godets can be in the form of mono- or duo-rollers, which draw or compress or relax the yarn G in stages at different speeds. Further apparatuses for treating the yarn G can be arranged therebetween, by means of which apparatuses the yarn G is, for example, tangled and/or textured and/or provided with an application and/or subjected to further treatment. According to the prior art, the yarn G is finally wound by a winder downstream of the treatment apparatus 12. According to the invention, the yarn G is transferred downstream of the treatment apparatus 12 directly to a collection and transport apparatus 14, which temporarily buffers the yarn G and then transfers it to a twisting apparatus 15. This is a continuous process in which the yarn G is not wound and temporarily stored separately but is transferred in a single step from the spin-drawing installation S to the twisting apparatus 15.

[0045] The yarn G is preferably delivered via a transport roller 13 and transferred to a collection and transport apparatus 14. The transport roller 13 can be associated with the spin-drawing installation S or it can be arranged as a separate component between the spin-drawing installation S and the collection and transport apparatus 14. The yarn G can be further drawn or relaxed by the transport roller 13. The transport roller 13 can thereby be either cooled or heated and/or can be arranged in a suitable housing which is filled with steam or conditioned gas.

[0046] The above-described installation components from the mixer 1 or the supply device 3 to the treatment apparatus 12 are referred to as a whole as the spin-drawing installation S.

[0047] According to FIGS. 1 and 2, the collection and transport apparatus 14 can be in the form of an endless revolving belt 20 on which the yarn G is deposited in windings or loops and is supplied to a twisting apparatus 15. The revolving belt 20 can have a length and width extent, so that one or more yarns G can be deposited thereon side by side in windings or loops over a length of several hundred metres. The revolving belt 20 can be held in an atmosphere of hot steam or a gas, which may accordingly make it necessary to provide a housing 16 or an enclosure. The collection and transport apparatus 14 serves as a buffer with which it is possible to compensate for different working speeds of the spin-drawing installation S and of the twisting apparatus 15 for a short time. For example, in the event of a change of the bobbins of the twisting apparatus 15 or in the event of a torn continuous filament E or yarn G in the spin-drawing installation S, the collection and transport apparatus 14 is for a short time able to compensate for a possible loss of production. The revolving belt 20 serves as the collection and transport apparatus in order to create the connection, upstream of an existing spin-drawing installation S, to a twisting device 15 installed downstream. The twisting apparatus 15 can here also be arranged in a different part of the building of the installation. With the surrounding housing 16, the collection and transport apparatus 14 can be configured to treat the yarn G in a special atmosphere, for example with inert gas or hot steam, or with freezing of the current molecular structure of the yarn G. In this exemplary embodiment, two yarns G are discharged from the treatment apparatus 12 and deposited via the transport roller 13 side by side on the belt 20, both yarns being introduced into a common (cabling) or separate (twisting) twisting apparatus 15. In principle, one yarn G or a plurality of yarns G can be supplied in parallel to the twisting apparatus 15 via the collection and transport apparatus 14.

[0048] According to the invention it is provided to adapt the spin-drawing installation S to the twisting apparatus 15 in terms of production speed. Preferably, the yarn G is delivered downstream of the treatment apparatus 12 and supplied to the collection and transport apparatus 14 at a speed of from 100 m/min to 150 m/min. The downstream twisting installation 15 is operated at a speed of from 10 m/min to 150 m/min. The principle of operation of the spin-drawing installation S remains the same. It is merely operated at a speed that is lower by a factor of 30, as a result of which the components to be used are much simpler and less expensive to produce. During normal operation, the spin-drawing installation S and the twisting apparatus 15 are preferably operated at the same speed, which can be, for example, from 100 m/min to 120 m/min. The collection and transport apparatus 14 is configured, for example, to accommodate a buffer capacity for a production period of the yarn G of one hour, that is to say to accommodate 6000 m of yarn at a production speed of 100 m/min. Such a buffer is sufficient, for example, to eliminate the breakage of a yarn G or of a continuous filament E without the twisting apparatus 15 having to be stopped. Such a buffer is likewise sufficient to allow the bobbins of the twisting apparatus 15 to be changed without stopping production of the spin-drawing installation S. If the buffer with produced yarn G is slowed down, for example as a result of breakage of a continuous filament and subsequent stoppage of the spin-drawing installation S, the production speed of the twisting apparatus 15 can be reduced at the same time, for example to 50 m/min. This can take place until the buffer for yarn G in the collection and transport apparatus 14 has had its speed returned to a defined desired value. To that end, the spin-drawing installation S is operated at an increased speed of up to 150 m/min. A controller of the installation as a whole is configured to adapt the production speed of the spin-drawing installation S and of the twisting apparatus 15 such that there is always a sufficient supply of yarn G at the transport and collection apparatus 14 to compensate for disruptions in production or irregularities in production.

[0049] In an alternative embodiment, the speed of the spin-drawing installation S and the speed of the twisting apparatus 15 can be brought more closely together. However, this requires a particularly complex, for example magnetic, bearing for the spindles of the twisting apparatus 15, so that the twisting apparatus 15 is able to operate at a rotational speed far greater than 12,000 rpm and is operated in continuous operation at a speed of from 10 m/min to 300 m/min. Here too, it is provided according to the invention to adapt the spin-drawing installation S to the twisting apparatus 15 in terms of production speed. In this embodiment, the yarn G is delivered downstream of the treatment apparatus 12 at a speed of from 200 m/min to 300 m/min and supplied to the collection and transport apparatus 14. The downstream twisting apparatus 15 is operated at a speed of from 10 m/min to 300 m/min. The principle of operation of the spin-drawing installation S remains the same. It is merely operated with a speed that is lower by a factor of 15, for example, than according to the prior art, as a result of which the components to be used are much simpler and less expensive to produce. During normal operation, the spin-drawing installation S and the twisting apparatus 15 are preferably operated at the same speed, which can be, for example, from 200 m/min to 240 m/min. The collection and transport apparatus 14 is configured, for example, to accommodate a buffer capacity for a production period of the yarn G of half an hour, that is to say to accommodate 6000 m of yarn at a production speed of 200 m/min. Such a buffer is in any case sufficient to allow the bobbins of the twisting apparatus 15 to be changed without stopping production of the spin-drawing installation S. Depending on the extent of the disruption in the spin-drawing installation S, such a buffer may be sufficient, for example, to eliminate the breakage of a yarn G or of a continuous filament E without the twisting apparatus 15 having to be stopped. If the buffer with produced yarn G is slowed down, for example as a result of breakage of a continuous filament and subsequent stoppage of the spin-drawing installation S, the production speed of the twisting apparatus 15 can be reduced at the same time, for example to 50 m/min. This can take place until the buffer for yarn G in the collection and transport apparatus 14 has had its speed returned to a defined desired value. To that end, the spin-drawing installation S is operated at an increased speed of up to 300 m/min. A controller of the installation as a whole is configured to adapt the production speed of the spin-drawing installation S and of the twisting apparatus 15 such that there is always a sufficient supply of yarn G at the transport and collection apparatus 14 to compensate for disruptions in production or irregularities in production. Depending on the mode of operation of the spin-drawing installation and the available space for the collection and transport apparatus 14, a buffer for a loss of production of from 10 to 15 minutes may also be sufficient, in order to compensate for smaller disruptions or the change of the bobbins in the twisting apparatus 15.

[0050] FIG. 3 shows a collection and transport apparatus 14 which is in the form of a rotating drum 21 and, via the number of windings, is able to buffer the yarn G on the drum 21 for a short time. The drum 21 adapts itself in terms of its rotational speed to the output speed of the yarn G from the treatment apparatus 12. An increased or reduced input speed of the yarn G into the twisting apparatus 15 can be achieved via a thread guide 22, which is arranged parallel to the axis of the drum 21. The number of windings of the yarn G on the drum 21 is controlled via the thread guide 22. This embodiment of a collection and transport apparatus 14 also serves to buffer the yarn G in order to compensate for different speeds between the spin-drawing installation S and the twisting apparatus 15. The drum 21 can, however, also be heated or cooled or alternatively can be arranged in a housing 16 which is filled with a special atmosphere.

[0051] By way of example for all the other embodiments too, it is shown in this figure that two yarns G can leave the treatment apparatus 12 and be relaxed by means of a delivery apparatus, which may be in the form of at least one transport roller 13. This operation can be assisted in the delivery apparatus by means of hot steam or conditioned gas.

[0052] FIG. 4 shows a further collection and transport apparatus 14 which comprises at least two cylinders 23, 24 which are spaced apart from one another and which are able to transport the yarn G further and temporarily buffer it. The yarn G always passes in windings around both cylinders 23, 24, which are at a distance from one another and are controllable in terms of their rotational speed relative to one another. This embodiment of a collection and transport apparatus 14 also serves to buffer the yarn G in order to compensate for different speeds between the spin-drawing installation S and the twisting apparatus 15. The cylinders 23, 24 can, however, also be heated or cooled or alternatively can be arranged in a housing 16 which is filled with a special atmosphere. This collection and transport apparatus 14 can of course have further cylinders, that is to say more than two cylinders 23, 24, which are at a distance from one another and are controllable in terms of their rotational speed relative to one another.

[0053] FIG. 5 shows a further exemplary embodiment of a collection and transport apparatus 14 which is in the form of a buffer 25 having a first row of deflection rollers 26a and a second row of deflection rollers 26b, the yarn G looping alternately around a deflection roller of the first row 26a and then around a deflection roller of the second row 26b. As a result of the variable distance of the rows of deflection rollers 26a, 26b from one another, the yarn G can be buffered and passed to the twisting apparatus 15, and thus it is possible to compensate for a difference in the speed of the yarn G from leaving the treatment apparatus 12 to entering the twisting apparatus 15. This buffer 25 can also be arranged in a housing 16 which is filled with a special atmosphere. The deflection rollers 26a, 26b can likewise be configured to be heated or cooled.

[0054] According to the invention, the spin-drawing installation S is operated at a lower delivery speed than according to the prior art. The production speed of the spin-drawing installation is equal to or slightly higher than that of the twisting apparatus 15. The production of the spin-drawing installation S is slowed down by a factor of from 15 to 30, which has prevented experts from considering this in respect of the investment of a spin-drawing installation, because the price per tonne of yarn would rise by almost the same factor. However, because of the lower productivity or production speed, the spin-drawing installation can be of a more simple design, as a result of which the investment costs fall. What is important, however, is that all handling and temporary storage between the spin-drawing installation S and the twisting apparatus 15 is omitted, as a result of which the method according to the invention is worthwhile again in terms of operating costs.

[0055] The invention has the advantage that, by means of the collection and transport apparatus 14, a continuous process is possible without interruption from production of the continuous filaments E to the twisted yarn. The collection and transport apparatus 14 can be configured to compensate for a production difference between the spin-drawing installation S and the twisting apparatus 15. In addition, the collection and transport apparatus 14 can be configured to further treat the yarn by means of gas or hot steam or by means of temperature-controlled drums, cylinders or deflection rollers. The installation can be operated without interruption in a line from the liquid plastics material to the twisted yarn, which saves space and reduces storage capacity and handling costs. Although the spin-drawing installation is operated with a lower capacity compared to the prior art, this is more cost-effective overall because the spin-drawing installation is operated without interruption.

REFERENCE NUMBERS

[0056] 1 Mixer [0057] 2 Melt container [0058] 3 Supply device [0059] 4 Extruder [0060] 5 Spinning beam [0061] 6 Spinning pump [0062] 7 Spinneret [0063] 8 Heater [0064] 9 Blow shaft [0065] 10 Drop pipe [0066] 11 Godet [0067] 12 Treatment apparatus [0068] 13 Transport roller (e.g., a delivery apparatus) [0069] 14 Collection and transport apparatus [0070] 15 Twisting apparatus [0071] 16 Housing [0072] 17 Twist stopper [0073] 20 Belt [0074] 21 Drum [0075] 22 Thread guide [0076] 23 Cylinder [0077] 24 Cylinder [0078] 25 Buffer [0079] 26a, 26b Rows with deflection rollers [0080] E Continuous filament [0081] G Yarn [0082] S Spin-drawing installation