Spinning jet

Arcraft structures Arcraft windshields Ar drying Ar electrode Arex Ar filters Arfocon Ar fresheners Ar hydrocarbons Air-jet spinning Aliens... 

In an evaluation of various techniques for droplet generation,1[88] periodic vibration of liquid jet, spinning disk and ultrasonic atomization techniques have been rated as the most appropriate methods for producing monodisperse sprays. These techniques were found to be very effective and appeared promising for refinement,... 

Air filters Airfocon Air fresheners Air hydrocarbons Air-jet spinning Airlens... 

Badrossamay MR et al (2010) Nanoflber assembly by rotary jet-spinning. Nano Lett 10 (6) 2257-2261... 

This report discusses four technologies single water jet, spinning twin water jets, lathe machining, and rotary knife grinding (RKG). The size reduction methods are compared among each other for safety, efficiency, and performance. 

Fiber processing, spinning, jet For most purposes this process is similar to fiber spinning. Hot gas jet spinning uses a directed blast or jet of hot gas to pull molten plastic from a die lip and extending it into fine fibers. 

In situ polymerisation reactions have also been applied to the preparation of other polymer-nanotube composites. For example, Kumar et al have synthesised new ultra-strong PBO composites in the presence of SWNTs in poly(phosphoric acid) (PPA) by in situ PBO polymerisation. After the polymerisation, PBO-SWNT composite fibres have been spun from the liquid crystalline solutions using dry-jet spinning. 

Where polymeric fibres are mixed with natural fibres, the continuous multifilaments are cut into lengths according to the mean length of the natural fibres. The fibre-mix is then made into yams via ring spinning, rotor spinning or air-jet spinning. 

Air Jet spinning n. A spinning system in which yarn is made by wrapping fibers around a core stream of fibers with compressed air. In this process, the fibers are drafted to appropriate sliver size, then fed to the air jet chambers where they are twisted, first in one direction, then in the reverse direction in a second chamber. They are stabilized after each twisting operation. 

Jet spinning n. For most purposes, similar to melt spiiming of staple fiber. Hot-gas-jet spiiming uses a directed jet of hot gas to pull molten polymer from a die hp and instantly draw it into fine fibers. Kadolph SJJ, Langford AL (2001) Textiles. Pearson Education, New York. 

PEDOTiPSS dispersions can be deposited by multiple techniques including spin coating, doctor blading, dip coating or ink jetting. Spin coating is regarded as the most reliable technique to obtain uniform thin layers. 

Rotating jet spinning Combination of centrifugation and pinning to produce... 

Badrossamay MR, Balachandran K, Capulli AK, Golecki HM, Agarwal A, Goss JA, Kim H, Shin K, Parker KK (2014) Engineering hybrid polymer-protein super-aligned nanofibers via rotary jet spinning. Biomater 35(10) 3188-3197... 

Figure 19.14 Schematic illustration of the basic setup for electrospinning, (a) The typical SEM image of nonwoven mat of polymer nanofibers, (b) CCD image of the stable con-jet spinning model. Photographs illustrating the instability region of a liquid jet and the capture time was on two different scales (c) 1/250 s and, (d) 18 ns. (Reprinted from Polymer, 42, Y.M. Shin, M.M. Hohman, M.P. Brenner and G.C. Rutledge Experimental characterization of electrospinning The electrically forced jet and instabilities, 9955-9967, 2001, with permission from Elsevier.)...

The crucial factor when increasing the spinning speed is the twist insertion. Ideally, the mechanically moved mass is reduced to a minimum. Pneumatic methods have hence come into focus in recent years. In addition to higher yarn speed, wear of machine components owing to friction is also expected to be reduced. At present, there are two machine manufacturers offering air-jet spinning machines, Murata (MVS process, introduced 2003, Japan) and Rieter (2011, Switzerland). 

The carded sliver is drafted, similar to other spinning principles, on draw frames and then fed into the machine. The draft in the air-jet spinning machine is around 40- to 200-fold. Due to the high spinning speed of up to 450 m/min, the drafting... 

Similar to OE-rotor spinning, the yarns are directly wound onto cross-wound bobbins. Drawbacks compared to conventional spinning processes are the high investment and the difficult start of the spinning process. Another disadvantage is the removal of short fibers, hence only medium to long fibers are suitable for this process. At present, mainly 100% cotton or cotton blends with polyester are used. See Fig. 3.24 for an example of an air-jet spinning machine. 

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