Papers by Keyword: Inductor

Abstract: The article presents the technological scheme of the “stretching-over” hybrid technology, when the workpiece is simultaneously affected by two sources of loading: static and dynamic. It is proposed to use a pulsed magnetic field as a dynamic load. In this case, the tightening punch is equipped with an inductor connected to a magnetic-pulse unit. As a result of computer simulation, the distribution patterns of the stress-strain state in a tight-fitting workpiece were obtained both in the case of a conventional tight-fitting and with the proposed hybrid one. It was found that exposure to a pulsed magnetic field changes the stress-strain state, making it possible to intensify the stretching process.

Abstract: To improve the structure of metal in welded butt joints of railway rails produced by flash-butt welding and increase the reliability of butt joints, it is advisable to carry out their induction heat treatment using high-frequency currents. Solving the problem of a uniform bulk heating of weld metal of railway rails in a narrow area during its heat treatment remains an urgent task. The work describes the principle of designing an inductor without magnetic cores for carrying out a uniform bulk heat treatment of welded butt joints of railway rails for realization of favorable phase transformations of metal and normalization of its structure. The principle is based on the physical laws of propagation of electromagnetic fields and electric currents in the inductor and a rail. Based on the carried out investigations, an inductor was designed that has a variable shape along the perimeter of a rail and a variable distance from it, as well as a partial splitting of the inductor busbar for current parallelization, which provides a uniform bulk heating of a rail butt joint. Splitting of the inductor busbar allowed adjusting the propagation of currents in the inductor and a rail in such a way as to avoid overheating of a rail in its particular areas without a significant increase in the distance between the inductor and a rail, and respectively without a significant increase in the reactive power of the “inductor-product” system. The carried out experiments on heating the welded butt joint of a rail by the designed inductor showed the indices of uniformity and rate of its bulk heating, which are acceptable for heat treatment of rails both on the surface as well as in the depth of a rail in a narrow heating zone with providing the required temperature levels.

Abstract: The performed research helped to develop and implement a new process of manufacturing small high pressure cylinders, in which the operation of pressing of tubular blanks with preliminary induction heating of the deformation zone. A two-layer inductor was designed and an industrial unit for preliminary differentiated induction pre-heating for the developed technological process. The forming rate was determined, ensuring preservation of the specified temperature difference and manufacturing of deformed tube end in accordance with the requirements for its geometry. Heating die-blocks were designed for blanks deforming for application in manufacturing of diameter, allowing keeping the necessary temperature gradient at deforming. Developed technological lubricants can be used for obtaining high quality products, increase in labor protection and die-blocks durability.

Abstract: The paper describes principles of construction of multi-block and multi-station pulse-magnetic installations. Main requirements for selection of elements of energy storages of installations with high stored energy and high frequency of the discharging current are presented. Examples of hardware implementation of the installations are shown.

Abstract: Authors of article offer the mixed technology of receiving the facilitated screening casing from aluminum foil of 0,15÷0,2 mm thickness by the means of magnetic-pulse welding preforming (MPWP) combining thermal and force impact on processed material.The physical entity of MPWF is described, parameters of the modes of welding are specified, metallographic researches of a zone of welded connection are conducted.The press of double action realizing static and impulse loading on processed material is developed.

Abstract: In order to realize the online monitoring for iron grade of the magnetite during the dressing process, an iron grade fast measurement method based on electromagnetic induction is given, critical segment of the method is to make the iron grade information acquisition by adopting an iron ore core inductance sensor. Magnetic field analysis for iron ore core inductors of the sensor is explored in the paper. Taking a magnetite in certain regions of Liaoning as the test typical sample examples, physicochemical properties of its raw ore are analyzed, the iron ore samples are prepared and made, and the dressing process are completed. Ferromagnetics features of the magnetite samples above is analyzed, magnetic field distribution of the iron ore core inductor is analyzed, and analytic calculation formula of the magnetic fields is derived. Theory of solving the inductance of iron ore core inductor adopting finite element method of energy is discussed. Furthermore, total finite element design for the iron ore core inductor is made; distribution of electromagnetic field is analyzed. Influence regulations of self-inductance coefficients of the inductor are obtained, thus, the optimal combination of structural parameters of the inductor are designed. There is important practical significance to realize the iron grade testing automation for magnetite and other iron ores of the thesis research above.

Abstract: Thermal stress points in an inductor can cause insulation deterioration and ageing, leading to winding faults, while high magnetic flux causes interference. In this paper, the thermal and magnetic behaviors of inductors with different winding geometries are investigated using the Finite Element Method (FEM) based on 2-Dimension and 3-Dimension model of an inductor. Inductors with different winding geometries have different thermal envelopes and the geometry with the slowest thermal transition has fewer thermal stress points potentially reducing winding faults at the conductor. Furthermore, slow thermal transition would result in greater magnetic field coverage with no magnetic flux outside boundary of the inductor.

Abstract: In this paper, the main work is focused on the design, simulation and fabrication of 2012-type low pass filter(LPF) using the technology of low temperature co-fired ceramic(LTCC). The three-order and -type LPF with 130MHz cut-off frequency and 260MHz out-band rejection is successfully implemented using two kinds of green tape with relative permittivity of 14 and relative permeability of 60 respectively. The measured results agree well with the simulated data and the design process is proved to be effective and reasonable.

Abstract: This paper presents a tunable inductor using MEMS technology .This tunable spiral inductor is designed in order to be used in RF circuits such as : controlled oscillators with voltage (VCO) , matching networks ,amplifiers etc . The electrostatic method is employed for tuning the inductor by the movement of cantilever beam downward and changing the value of magnetic flux. Value of inductance varies fram 1.15nh to 0.561 nh .therefore ,tunablity of 66.21% was achieved .Maximum quality factor in the above inductor was achieved az 13.88 in the frequency 0f 12 GHz and the value of resonance frequency was achieved as 19.5 GHz

Abstract: This paper reports the design of a tunable radio-frequency (RF) inductor and analyses the parameters that influence the quality factor (Q) of the inductor. In our paper we mainly discuss the influence of the thickness of the metal layer on the Q when other parameters are fixed. In order to achieve the high thickness, we use SU-8 as our photoresist instead of the traditional photoresist. Through the analysis, we calculate out the thickness of the metal layer is 23um when the Q reaches to maximum.