Various techniques involve a device for entangling a plurality of individual threads of a composite thread in a melt-spinning process for the production of crimped yarns. The device to this end has a plurality of entanglement nozzles which are collectively held on a support. In order to enable a flexible utilization of the entanglement nozzles and of thread guiding, the entanglement nozzles on the support are assigned at least one thread guide in such a manner that the threads are guidable optionally in the entanglement nozzles and/or in the thread guide.

Various techniques involve a device for entangling a plurality of individual threads of a composite thread in a melt-spinning process for the production of crimped yarns. The device to this end has a plurality of entanglement nozzles which are collectively held on a support. In order to enable a flexible utilization of the entanglement nozzles and of thread guiding, the entanglement nozzles on the support are assigned at least one thread guide in such a manner that the threads are guidable optionally in the entanglement nozzles and/or in the thread guide.

Provided herein is a system for guiding polymeric fibers using ultrasonic waves. In particular, this application discloses a system of producing fibers including an emitter, a fiber guidance system, and a collector. The emitter supplies the polymer jet into the fiber guidance system. The fiber guidance system includes a phased array of transducers and a control system. The control system directs the phased array of transducers to generate acoustic energy to create an acoustic hologram and guide the polymer jet in space to form the polymer fiber before it is collected in the collector.

Process for manufacturing carbon fibers, includes a first spinning step of a fiber of PAN precursor and a second oxidation/carbonization step of the fiber and the plant thereof. The spinning and oxidation/carbonization steps are performed directly in line and continuously, and hence without any stocking buffer area of a PAN precursor between the two steps. The spinning step is performed at low speed, so that the output speed from the spinning step, downstream of the stretching operations, is a speed falling within the range of the suitable processing speeds in the subsequent oxidation/carbonization step. Moreover, the spinning step is performed in a modular way on a plurality of spinning modules aligned in one or more rows, each spinning module having a productivity not above 10% of the overall productivity of the spinning step. In any individual spinning module, the fibers downstream of the spinning area follow zig-zag, rectilinear paths.

An object is to provide a production method for a precarbonized fiber bundle and a precarbonization furnace capable of continuously producing the precarbonized fiber bundle for a long period of time by efficiently discharging a decomposition gas containing a tar component generated when performing a precarbonization treatment at the time of carbon fiber production and retained in a heat treatment chamber throughout the heat treatment chamber. The production method for a precarbonized fiber bundle includes allowing an aligned stabilized fiber bundle vertically arranged in one or two or more tiers to travel horizontally in a heat treatment chamber and heat-treating and precarbonizing the stabilized fiber bundle at a maximum temperature of 300 to 1,000 C. using an inert gas supplied from an inlet side and an outlet side of the heat treatment chamber, in which a flow rate ratio Q2/Q1 satisfies Formula (1) below, where Q1 represents a volume flow rate of gas in a first exhaust discharged out of the heat treatment chamber from a position higher than a position of an uppermost tier of the traveling stabilized fiber bundle, and Q2 represents a volume flow rate of gas in a second exhaust discharged out of the heat treatment chamber from a position lower than the position of the uppermost tier of the traveling stabilized fiber bundle:
0.01Q2/Q10.5Formula (1).