Abstract: The article deals with diagnostics of machine tool precision and necessity to train basic routines of measurement and its preparation. Such training is essential for efficiency of diagnostic processes as preparation is usually the most time-consuming and skill-demanding part of overall measurement. The article roughly describes simulation of machine tool errors on proposed experimental device and its implementation into the training process in order to gain experiences with measurement on machine tools in wide scale of conditions. Described device is designed to simulate several geometrical errors, inaccuracies and environmental impacts on precision of positioning which affects not only machine precision but also effectivity of measurement itself.
Abstract: Overall efficiency represents an important qualitative property for devices used in manufacturing technology. This paper presents the mathematical modeling of calculating worm gear overall efficiency. The studied worm gear types goes into numerous manufacturing devices component. Mathematical model validation was experimentally performed on a tool sharpening device with a helicoidally profile. The analytical calculated results were closed to experimentally determined results, which partially validates the model proposed in the paper.
Abstract: The main purpose of this paper is to analyze the influence of cutting regime parameters in case of dry turning of an aluminum alloy. For turning process of the aluminum alloy was used Sandvik insert DCGX 11 T3 08 Al H10. The influence of the main cutting parameters on the surface quality was analyzed using a statistical method (ANOVA) used to test differences between two or more means. Based on a mathematical model can be calculated the surface roughness taking into account the cutting speed, the feed rate and the depth of cutting.
Abstract: Maintaining positions in the highly competitive environment of global markets in the field of rolling bearings causes constant need for production efficiency increase. The products now have higher quality demands along with shorter production times and reduced production costs. The aim of the article is to optimize finishing manufacturing processes of bearing races, after the analysis of quality demands of large-diameter bearings, manufacturing options and examining of current knowledge about hardened steels turning, focusing on the replacement of grinding operations by hard turning operations with intention to minimize machine time and production cost together with keeping the quality of machined surface.
Abstract: In this article, the authors have analysed the influence of quenching temperature (TQ) on the mechanical properties of a dual-phase steel with 0.094 % C and 0.53% Mn. In order to obtain a ferrite-martensite structure, specimens of this material have been the subjected to intercritical quenching that consisted of heating at 750, 770, 790, 810 and 830 °C, maintaining for 30 minutes and cooling in water. These specimens have then been subjected to metallographic analysis and tensile test in order to determine the volume fraction of martensite (VM) in the structure, ultimate tensile strength (Rm), the 0.2% offset yield strength (Rp0.2), the total elongation (A5) and the Rp0.2/Rm ratio.
Abstract: This paper fits into an experimental researches complex, regarding the surface roughness dependency on the cutting parameters of 7136 aluminum alloy machining. The purpose of this paper is to identify by experiments the influence of feed per tooth variation on surface roughness. A range of feed per tooth was used while the cutting speed and the cutting depth were constrained per minimum and maximum requirements defined for the given cutting tool. The experiments were conducted on Al7136 because it is a new material and I have identified the need for its use in the aircraft industry.
Abstract: Processing metallic materials by cutting using good electricity conductor cutting edges it appears an electrical current due mainly to the temperature in the cutting zone. Analyzing of the electrical current the information about the unfolding mode of the cutting process can be obtained. The cutting electrical current can be used in several applications: the estimation of the temperature in the cutting zone, the estimation of the cutting forces, the identification of the wear state of the cutting edge etc. The first researches were started in Russia and they were based on the utilization of the cutting electrical current to measure the temperature in the cutting zone. Afterwards, other applications were identified in the literature and the researches were extended in other countries like India, Japan, USA, Brazil, France, Bangladesh and Romania. This paper presents a review of the researches about the electrical current which appears at cutting process.
Abstract: One relatively new variant in gear transmissions is the rolling gear boxes. The rolling transmission wheels have variable pitch and variable screw profile surface section. In this paper it is presented the geometry of used helically surfaces and one new machining technology developed by our team. It is used the method of high machining, with high precision turning, which is a promising solution. The profile manufacturing can only be made on high precisions turning. The experimental researches were realized at the Direct-Line Ltd. in Budapest.
Abstract: The objective of this paper is to predict and analyze the surface roughness during dry turning of austenitic stainless steel AISI 304. In this study a new carbide insert developed by Mitsubishi was used for the cutting of this material. By using the ANOVA method, the influence of the main processing parameters on the surface quality was analyzed. By using a mathematical regression method a mathematical model was developed. It can calculate the surface roughness taking into account the cutting speed, the feed rate and the depth of cutting.