Study On Difficulties Of Using Far Infrared Radiation Heating Technique On Filament Sizing Machine

In this thesis, a few difficulties of using far infrared radiation heating technique on filament sizing machine was studied. Solutions to the difficulties were gained through theoretic analysis and experimental method, which provided reference for enterprise to manufacture far infrared pre-drying chamber on filament sizing machine.Hot air circulation heating has been used on the pre-drying chamber of filament sizing machine for a long time. As the development of market economy, high efficiency, high speed and high quality for sizing is more and more emphasized by enterprises, but hot air circulation heating transfers heat through convection method which has a characteristic of low efficiency, besides, high speed of the air circulation inside the chamber would cause warps attach to their adjacent ones which lead to deteriorate the sizing effects. Therefore, the increase of sizing speed is limited by the hot air circulation heating method. The successful application of far infrared radiation heating technique in other fields proved that this heating method has the following advantages: energy saving, high efficiency and high speed, good quality products, invest little and take effect quick, simple equipment structure and easy maintain, safe and reliable. So far infrared radiation heating technique was selected to be used in development and industrialization for warping-sizing-rebeaming product line, which is a project of New & Hi Tech Oriented Industries of Jiangsu Province.In order to using far infrared radiation heating technique on filament sizing machine, resolutions should be found firstly for the following difficulties: (1) Chose a wavelength as the main wavelength of the radiant energy in the chamber according to the matching absorption theory. (2) Selected a reasonable temperature for the heat source of the FIR emitter in the light of the main wavelength. (3) Made a choice of the material used for the wall within the chamber based on the consideration of energy saving. (4) Estimate the electric power consumption of the chamber in accordance with the designed drying capability.The application of far infrared radiation heating has had no guidance of related fundamental research so far, consequently, under the direction of existing theory, a method of combining theoretic analysis with experiment was used to overcome those difficulties.Firstly, accomplishing approximate 80% of the total drying assignment, which means making the moisture regain of the sized filament reduce to 25% from 105%, was considered to be the designed drying capability of the pre-drying chamber after practical measurement and investigation. Secondly, infrared spectrograms of sized polyester filament with different moisture regains were researched and a wavelength of 2.96μm was selected to be the main wavelength of the radiant energy, furthermore, an optimal distributing of emitter inside the chamber was arranged in accordance with the relationship between moisture regain and absorptivity. Thirdly, a variety of radiant emitters were surveyed and FIR oriented emitter was selected to be the energy source of the FIR chamber at last, then, the ideal temperature of FIR emitter's heat source was theoretically calculated and verified by experiments, a temperature of 945℃was selected to be the reasonable temperature of the heat source in the end. Fourthly, properties of the wall within the chamber were analyzed, mirror like stainless steel plate and aluminum foil were selected as the primary choice. Finally, a method was provided to estimate the electric power consumption of the chamber and designs of the main components of the platform used for experimenting were given.