Method and apparatus for processing fibers
A process and an installation for producing a yarn in accordance with an airjet-spinning method. A carded fibre sliver is subjected to more than three-fold drawing without levelling at a carding machine and deposited in a can (C). At least nine fibre slivers are fed draftfree from cans (C) to a draw frame and subjected to at least 8.5-fold drawing to form a fibre sliver and deposited in a can (C 1 ). The fibre sliver in the cans (C 1 ) is then fed to a spinning station of an airjet-spinning machine.
1. A process for processing fibres, comprising steps of:
producing on a carding machine a carded fibre sliver;
subjecting the carded fibre sliver to preliminary drawing in an integrated draw frame at the carding machine to produce a pre-drawn fibre sliver;
depositing the pre-drawn fibre sliver in respective ones of a plurality of first cans;
feeding draftfree at least 9 to 12 of the pre-drawn fibre slivers from a corresponding number of the first cans to a second draw frame and drawing the at least 9 to 12 pre-drawn fibre slivers on the second draw frame to form a drawn fibre sliver, wherein the number of first cans from which the at least 9 to 12 fibre slivers are fed draftfree to the second draw frame corresponds to the number of pre-drawn fibres being fed to the second draw frame;
depositing the drawn fibre sliver in respective ones of a plurality of second cans; and
feeding the drawn fibre sliver from the respective ones of the second cans to a spinning station of an airjet-spinning machine.
2. The process according to claim 1 , further including subjecting the drawn fibre sliver to at least 20-fold drawing with respect to the carded fibre sliver.
3. The process according to claim 1 , wherein the subjecting step includes subjecting the carded fibre sliver to at least 2.5-fold, 3-fold or 3.5-fold preliminary drawing at the carding machine.
4. The process according to claim 1 , wherein the carded fibre sliver has at least 2.9 ktex or 3.5 ktex.
5. The process according to claim 1 , wherein the subjecting step includes subjecting the pre-drawn fibre sliver to at least 8-fold, 8.5-fold or 9-fold drawing in the second draw frame.
6. An installation for producing a yarn, wherein the installation includes: a carding machine; an integrated draw frame and a can changer arranged at the carding machine for receiving fibre sliver from the carding machine, preliminary drawing the fibre sliver without levelling by the intergrated draw frame to form pre-drawn fibre slivers and depositing the pre-drawn sliver in respective ones of a plurality of cans provided by the can changer; a single drawing unit in a form of an autoleveller drawing frame, wherein at least 9 to 12 pre-drawn fibre slivers are fed draftfree from a corresponding number of the cans to the single drawing unit; and a driven creel and an airjet spinning machine arranged downstream of the single drawing frame, and wherein the installation is adapted to be operated in accordance the process according to claim 1 .
7. An installation for producing a yarn in accordance with an airjet-spinning method, comprising:
a carding machine for producing fibre sliver;
an integrated draw frame and a can changer arranged at the carding machine for preliminary drawing of the fibre sliver without levelling and depositing the preliminary drawn fibre sliver in respective ones of a plurality of cans arranged by the can changer;
a single drawing unit in a form of an autoleveller drawing unit arranged to receive the preliminary drawn fibre sliver from a respective one of the plurality of cans; and
a driven creel and an airjet spinning machine arranged downstream of the single drawing unit.
8. The installation according to claim 7 , wherein the carding machine has a transverse sliver take-off.
9. The installation according to claim 7 further including a sliver loop buffer arranged between the carding machine and the integrated draw frame.
10. The installation according to claim 7 , wherein the driven creel includes a drive which is operable and controllable independently of a drive of the drawing unit.
11. The installation according to claim 7 , wherein the single drawing unit includes a draw frame autoleveller which adapts a main draft of the single drawing unit to mass fluctuations of incoming fibre slivers.
12. The installation according to claim 11 , further including a funnel arranged upstream of the draw frame autoleveller that has an opening angle that decreases in a sliver running direction.
13. The installation according to claim 12 , wherein the opening angle decreases stepwise or continuously.
14. A process for processing fibres, comprising steps of:
producing on a carding machine a carded fibre sliver,
subjecting the carded fibre sliver to preliminary drawing to produce a pre-drawn fibre sliver, wherein the subjecting step includes effecting the preliminary drawing of the fibre sliver at the carding machine without levelling;
depositing the pre-drawn fibre sliver in respective ones of a plurality of second cans;
feeding draftfree at least 9 to 12 of the pre-drawn fibre slivers from a corresponding number of the first cans to a second draw frame and drawing the at least 9 to 12 pre-drawn fibre slivers on the draw frame to form a drawn fibre sliver;
depositing the drawn fibre sliver in respective ones of a plurality of second cans; and
feeding the drawn fibre sliver in respective ones of the second cans to a spinning station of an airjet-spinning machine.
15. A process for processing fibres, comprising steps of:
producing at least 80 kg/h of carded fibre sliver on a carding machine;
subjecting the carded fibre sliver to preliminary drawing to produce a pre-drawn fibre sliver;
depositing the drawn fibre sliver in respective ones of a plurality of second cans;
feeding draftfree at least 9 to 12 of the pre-drawn fibre slivers from a corresponding number of the first cans to a second draw frame and drawing the at least 9 to 12 pre-drawn fibre slivers on the draw frame to form a drawn fibre sliver;
depositing the drawn fibre sliver in respective ones of a plurality of second cans; and
feeding the drawn fibre sliver in respective ones of the second cans to a spinning station of an airjet-spinning machine.
16. A process for processing fibres, comprising steps of:
producing on a carding machine a carded fibre sliver at a rate of at least 100 m/min;
subjecting the carded fibre sliver to preliminary drawing to produce a pre-drawn fibre sliver;
depositing the drawn fibre sliver in respective ones of a plurality of first cans;
buffering the carded fibre sliver at the carding machine during a change of one of the first cans at the carding machine to another one of the first cans;
during the change of the first cans at the carding machine, continuing to produce the carded fibre sliver in the carding machine at the rate of at least 100 m/min;
feeding draftfree at least 9 to 12 of the pre-drawn fibre slivers from a corresponding number of the first cans to a second draw frame and drawing the at least 9 to 12 pre-drawn fibre slivers on the draw frame to form a drawn fibre sliver;
depositing the drawn fibre sliver in respective ones of a plurality of second cans; and
feeding the drawn fibre sliver in respective ones of the second cans to a spinning station of an airjet-spinning machine.