Papers by Keyword: Profile

Abstract: In this paper, we consider a detailed technological process for manufacturing parts, namely, a gear wheel. The proposed method with the intervention of modern 3D modelling makes it possible to improve the main indicators of quality and strength of parts. Based on the results obtained, a cycloid transcendental system of circular motion of a gear wheel with the specified basic parameters was modelled. Using multifunctional modules, we studied the vibrations of the gear wheel at different points in time. It was found that due to the fatigue and contact strength, it is possible to ensure uniform flexural strength of the gear teeth. And also, by adjusting the profile of the teeth of the part, we selected the desired strengthening coefficient. The presented dependence of the angles of inclination of the gear teeth on the transformation coefficient allows you to improve the main indicators of quality and strength by at least 2 %.

Abstract: We report significant advancements in corona-based non-contact capacitance-voltage (CnCV) metrology recently developed for comprehensive C-V characterization of SiC and other wide bandgap semiconductors. The technique answers the industries needs for nondestructive, cost-effective C-V dopant monitoring for material and device development and manufacturing control. Excellent precision and matching to mercury probe CV is demonstrated for SiC, Ga₂O₃, GaN and AlGaN/GaN structures over a concentration range from 10¹⁴cm^-3 to 2x10¹⁹cm^-3. The emphasis in the present work is on improvement of CnCV in dopant depth profiling resolution and measurement throughout. This is achieved with a variable charge method that in-situ adjusts corona charging increments in response to changes in dopant concentration. Results are presented for multi-layer epitaxial SiC and for 2DEG in AlGaN/GaN HEMT structures. The latter represents an extreme case of high-low concentration profiling with a transition from 10²⁰electrons/cm^-3 in the 2D electron gas to a fully depleted well and dopant concentration in the 10¹⁵cm^-3 range.

Abstract: This paper explains and demonstrates how miniature gears of excellent surface quality can be manufactured by modern machining methods. Necessity of gear finishing by post processes such as grinding, lapping, honing etc. is the major limitation of all conventional methods of miniature gear manufacturing. To overcome this limitation, modern machining methods such as wire-EDM, abrasive waterjet machining, and laser beam machining etc. have been explored. It resulted in significant achievements in geometric accuracy, surface finish, and integrity of miniature gears. Using modern machining methods, it is possible to manufacture gears equipped with precision finish (average roughness 1 μm), high geometric accuracy (DIN quality 5), and defect-free tooth surfaces at significantly low cost. This paper aims to facilitate researchers by providing information on important aspects as regards to the manufacturing of miniature gears by modern machining methods and hopes research and development in this area to establish the field further.

Abstract: Incremental sheet metal forming, is a non-conventional machining process which offers higher formability, flexibility and low cost of production than the traditional conventional forming process. Punch or tool used in this forming process consecutively forces the sheet to deform locally and ultimately gives the target profile. Various machining parameters, such as type of tool, tool path, tool size, feed rate and mechanical properties of sheet metal, like strength co-efficient, strain hardening index and ultimate tensile strength, effects the forming process and the formability of final product. In this research paper, Single Point Incremental Forming was simulated using Dassault system’s Abaqus 6.12-1 and results are obtained. Results of sheet profile and there change in thickness is investigated. For this paper, we simulated the process in abaqus. The tool diameter and rotational speed is find out for the production of parts through incremental forming. The simulation is done for two type of material with different mechanical properties. Various research papers were used to understand the process of incremental forming and its simulation.

Abstract: Electrochemical machining process is an advanced material removal technique offering high precision and introducing no heat damage to the work material. The shape and size of machined area are highly dependent on some process parameters such as voltage, electrolyte and inter-electrode gap. To further enable a more insight into the process performance, this paper investigates the influences of applied voltage, electrolyte concentration and inter-electrode gap on the shape and sizes of hole produced by the electrochemical drilling process. Titanium alloy (Ti-6Al-4V) was used as a work sample in this study as it has been extensively used in many advanced applications. The experimental result indicated that the use of high voltage and high electrolyte concentration can enlarge and deepen hole in the workpiece, while the inter-electrode gap provided less effect to the hole features. The maximum hole depth can reach 300 μm within 60 seconds when the applied voltage of 30 V, the inter-electrode gap of 10 μm and the electrolyte concentration of 10%wt were used. However, with this setup, the obtained cut profile became a non-uniform V-shaped hole. The use of lower voltage was instead recommended to yield a better cut quality with U-shaped profile.

Abstract: The article presents a study of a turbine blade profile and roughness measurement processes - the task facing any manufacturer of this part. The blade is one of the most complex regarding parts manufacture because of its complex profile. This profile should be measured in several sections on the feather on all profile elements - the suction side, pressure surface, leading and trailing edge of a blade. If the blade has a shroud platform, its profile should be also measured (and possibly the gland packing profile). It is also necessary to measure the feather end and base of blade profile. Finally, a separate independent task is the blade tang profile measurement.

Abstract: Screw rotor is a vital factor affecting the working efficiency of twin screw air compressor. Therefore, a type of twin screw air compressor in coal mine production process is taken as the research object. Firstly, the working principle and process of female and male rotor was introduced and analyzed. Then, according to the principle of parameter selection of the female and male rotor, the relevant design parameters of the female and male rotor are given. Finally, the vector equation and the tooth surface equation of the segmented line are deduced and established respectively for the end face profile and end face tooth surface of the rotor, the area and volume of the tooth are also calculated. The equation of the tooth surface is set up by rotation of rotor’s tooth direction, the inter-tooth area is composed of multi-section smooth curve and the top arc connected to form a circle, which can be obtained by means of analytical method. In order to better meet the requirements of the machining process, it is necessary to coordinate the female and male rotor profile on the coordinate axis when the end face of the rotor is non-symmetrical. This paper provides an important reference for selecting parameters of the rotor of the female and male and calculation of rotor profile.

Abstract: Data on capture fisheries in the southern region of East Java is a source of information that can be used to analyze the profile of fisheries that can be used as a reference in developing the port of fisheries especially in the southern region of East Java. The research objective was to determine the profile of fisheries in the southern region of East Java as the basis for the development of Fishery Port. The method used is descriptive analysis in order to obtain an idea of the profile of fisheries in the southern region of East Java. Potential data analysis and utilization of fisheries using Schaefer Methods. The results of the study are comparison of the eight districts in the southern region of East Java, Banyuwangi still dominate in the aspect of the number of fishing vessels, production and value of catch production and the number of fishermen. The Blitar district still lags behind in all aspects of fisheries. The dominant species of fish catches in the southern region of East Java include Lemuru (Sardinella sp), Tuna (Thunnus sp) Tongkol (Euthynus sp), Cakalang (Katsuwonus pelamis), and Layang (Decapterus sp). Potential and level of utilization of the fish in the south of East Java in the period 2009-2013 are still in a state of sustainable/under fishing. Development of fishing ports in southern Java needs to be supported entirely by the government, so it can improve fishermen's welfare and development of the economy in the region with the scale of priorities.

Abstract: In this paper we present a study of issues related for determination the real profile and the theoretical one of the precessional gear wheels. In the research process of the precessional gears profile appeared the problem of finding the geometrical error between fabricated profile and the ideal one after grinding process. The cause of the errors has technological and constructive nature. Processing technology of these specific gear wheels is one that still has many unknowns, therefore will be researched the part that is related to the occurrence of deviations from the ideal profile. The manufacturing of processing device and its elements also lead to geometric deviation of the profile, which will lead to adverse effects during operation. Measurement of manufactured profile using special equipment would involve high costs of time and money, therefore will be used computational methods and the statistic-mathematical method. The computational method is to find a better methodology to transform a file obtained from 3D scan (precessional gear wheel), which can be used only as a copy, into a file with functional extension. Such a conversion is very important to make especially for objects with complicated geometry such as precessional wheel profile. Transformation will result in surfaces and geometric objects that can be manipulated and compared to each other, with the aim of find deviations between ideal 3D models and the real ones. The methodology is relative simple: the triangular surfaces which form the shell of object should be approximated by flat, cylindrical, conical, etc. surfaces interlinked and filling the empty space between them with material. Once the scanned real object is transformed into a functional virtual file, it can not only be compared with the ideal model but also modified at the discretion of the user. Also we can find the coordinates of points which form the wheel contour line, which can be analyze and interpolate to obtain a mean value of scanned profile. Following the analysis of a profile obtaining was observed a small error of inclination of the gear teeth, due to the technological process. This methodology can be used to finding geometric errors also for other objects, gears etc.

Abstract: The Incremental Profile Forming process (IPF) is a new method to manufacture tubes and profiles with variable cross-section design along the centre-line of the profile. The innovative process design enables the combination of high workpiece complexity and high process flexibility. For this reason, a machine concept was developed and finally a prototype realized. The new machine consists of eight numerically controlled axes, which allow the processing of thinwalled tubes and profiles with a maximum diameter of 80 mm. The design of the machine combined with the control system leads to a forming technology with a high degree of flexibility, which is an advantage of the process. Depending on the final workpiece shape the forming process proceeds in several steps and can therefore be considered as an incremental forming process. Furthermore, the tool concept supports both a kinematical and a form-closed forming process.