• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.125-128
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• 1994

One of the abnormal motions of the projectile in the coil gun is spinning. It is found that the spinning force is closely related with air gap distance. Modified and detail analysis for the spinning is suggested in this paper. Two reasons for spinning force and Lorentz force affecting on the spinning are introduced. Nutation, which is a result of spinning, is explained there after.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.1
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• pp.79-85
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• 2012

This study investigates mainly on the technical development trend through the published papers, such as asymmetric metal spinning, metal spinning in heat treatment conditions and free mandrel spinning. Although the classical spinning, so called conventional, shear, tube spinning, uses the axisymmetric shaped mandrel(which is same inner shape of the final product), in new technologies the mandrel can be asymmetric one, spinning can be done without mandrel and also spinning is done with heat treatment together.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.620-623
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• 2002

Spinning has been used widely for the manufacture of hollow parts with rotational symmetry. With developing CNC machine, CNC machine center can be applied to the spinning processes. In this paper, a study on the development of CNC spinning technology without mandrel is carried out. The deforming process of the spinning process was simulated by DEFORM 3D to give basic design data.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.12
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• pp.874-880
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• 2015

This paper presents the vibration analysis of a deploying beam with spin when the beam has a time-dependent spinning speed. In the previous studies for the deploying beams with spin, the spinning speed was time-independent. However, it is more reasonable to consider the time-dependent spinning speed. The present study introduces the time-dependent spinning speed in the modeling. The Euler-Bernoulli beam theory and von Karman nonlinear strain theory are used together to derive the equations of motion. After the equations of motion are transformed into the weak forms, the weak forms are discretized. The natural frequency and dynamic response are obtained. The effect of the time-dependent spinning speed on the dynamic response is studied.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.6
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• pp.64-71
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• 2015

Spinning process is generally used for manufacturing axisymmetrical, thin-walled thickness and hollow circular cross-section parts. Traditional spinning technology is classified to conventional spinning and power spinning(shear spinning and flow forming). Literature surveys of spinning application for regenerative cooling chamber and divergent nozzle of liquid propellent rocket thrust chamber have been conducted. Most spinning technology has been used mandel for manufacturing chamber and nozzle. Recently, hot spinning has been used much compared to traditional cold spinning.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.241-244
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• 2010

This paper investigates mainly the new free mandrel technology of the metal spinning. Although the classical spinning, so called conventional, shear, tube spinning, uses the axisymmetric shaped mandrel(which is same inner shape of the final product), new technology does not use it.

• Textile Coloration and Finishing
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• v.34 no.1
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• pp.27-37
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• 2022

In this study, a study and interpretation of the spinning process in copolymerized aramid spinning was conducted. In order to proceed with the spinning process modeling and analysis, the spinning process was modeled through the physical property modeling of the spinning solution and the structural modeling of the spinneret, and structural stability and flow of the spinneret for this spinning were analyzed. After modeling the spinning solution and the spinneret in a virtual space, the pack pressure and flow rate when the spinning solution was discharged were simulated. Macroscopically, the structural stability of the spinneret was confirmed at the standard pack pressure (100 kg·f/cm²), and microscopically, the flow rate and pressure drop data of the spinning solution according to the L/D(Length (L)/Diameter (D)) value were analyzed. Based on the research and development of virtual engineering modeling and analysis, we present the possibility of changing the shape and mechanical properties of copolymer aramid fibers according to the spinning process.

• Journal of the Korean Society for Heat Treatment
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• v.33 no.6
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• pp.290-295
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• 2020

In this study, Electro spinning was carried out using Cabon nanotube 0.1%-Polyacrylonitrile 3%-Dimethylformamide 17% agitation solution. It was investigated the solute and solvent correlations according to the electro spinning voltages ranging form 5 to 40 kV, based on the SEM image. Except voltage 25 kV, electro spinning was failed due to the lack of electro spinning (less than 60%). Voltage 25 kV was showed excellent properties, and was confirmed Cabon nanotube 58.1 nm and diameter of Cabon nanotube + Polyacrylonitrile 1.76 ㎛ as shown SEM image. Also, the tensile test results were showed that SK Chemical prepreg electro spinning angle of 0 and 90 degrees were 137 MPa and 60 MPa, respectively.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.265-271
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• 2011

This paper investigates mainly on the technical development trend such as asymmetric technology and the metal spinning in heat treatment conditions. Although the classical spinning, so called conventional, shear, tube spinning, uses the axisymmetric shaped mandrel(which is same inner shape of the final product), new technology does not use it. and also spinning can be done with free mandrel.

• Journal of the Korean Professional Engineers Association
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• v.33 no.5
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• pp.38-44
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• 2000

High Quality is requested by Consumers more and more, Accordingly, the Quality of Yarns should be followed to satisfy the Desire of Consumers. Therefore, Yarn Hairiness, which has effects on Touch, Handle, iud Dyeing, is one of important factor. In order to reduce Yarn Hairiness, various tests were made in Spinning process and the following Spinning conditions can be suggested. -. The Speed should be as lower as possible. -. Using proper Tension Disc on Winding process. -. Using Colletor on Ring Spinning process. -. Using proper Ring and Traveller :n Ring Spinning process To get the best results, continuous Trial tests should be carried-on.