When face milling using a toroidal cutter, with a change in the depth of the cut, the entering angle varies as well. An experimental test of the influence of cutting parameters, such as the depth of ...the cut and the feed per tooth on the cutting force components and surface roughness parameters, was conducted. The experimental test was carried out using a DMU 100 monoBLOCK CNC machine with registration of cutting force components and surface roughness parameters Ra, Rz, and RSm. FEM analysis of the face-milling process was also carried out and compared with the experimental results. The average deviation of the FEM values for cutting force components does not exceed 12%. Experimental models were established for each force component. It was shown that the depth of the cut has the strongest influence on each force component. The feed per tooth has a little impact on the cutting force. The obtained model of the feed force component is the most complex, and the model of the F
component is only linear. The influence of the
parameter on the surface roughness parameters is nonlinear and nonmonotonic. In the range of approx.
= 2 mm, there is a maximum surface roughness.
Comparsion of measuring methods for the involute profile of the spur gear tooth is described in this paper. The gear profile measurement results from the universal toolmakers microscope are compared ...with the results of use of Zeiss coordinate measuring machine with Gear Pro software and with the results of the theoretical calculation of the reference profile. The proposed measurements methods can be successfully used in quality management of unit production of gear drives.
This paper examines the influence of the cutting parameters on the cutting forces and the surface roughness at the face milling process when machining aluminum alloy 7075 is obtained by the new SSM ...casting process. The parameters of the milling process are the cutting speed, the feed per tooth and the depth of cut. The experiments were performed according to the Taguchi method according to the L9 plan and the factors varied at three levels. For analysis of the effects of these parameters S/N ratio is used. In addition, ANOVA analysis was performed, i.e. analysis of the variance of the selected parameters. The analysis of the results shows that the optimal combination for the cutting force is the choice of a minimum level for all tested parameters. In contrast, for average arithmetic roughness, the optimal processing regime is achieved with minimum values for cutting speed and feed per tooth, whilst it is preferable to choose the cutting depth at the median level for the observed range. In addition, the study shows that the Taguchi method is suitable for solving the problem, where the research was carried out with a minimum number of tests compared to a full factorial experimental plan.
Spur gears have a wide application in the machine-building industry. Machining process primarily selected for these gears is hobbing method with modular hobs, or with Fellows cutters. Other methods ...which can be applied are profiling using the pull broaches, while the finishing can be done by gear shaving or grinding by the Maag, Niles or Reishauer methods. Moreover, in small (or unit) production, they may be formed using disc- or finger-type modular cutters. The article presents a method for cutting spur gears using a disc-type mill with a variable cutting plate profile. The influence of the number of blades of the presented milling cutter on the accuracy of the worked tooth profile was investigated.
This paper presents the results of FEM numerical simulations, of the HC260Y steelsheet mechanical clinching process. The starting tool parameters were chosen for the central composite design of ...experiments, in order to find out which tool parameters have the largest contribution to the sheet joint interlock. Assessment of the mathematical model, and analysis of variance (ANOVA) were performed within the design of experiments. This numerical analysis was done to find the most suitable tool geometry and tool work stresses, so that the tool sets for further experiments could be manufactured and results compared with numerical results.
Reliable measurement of surface roughness (Ra) is extremely important for quality control of production processes. The cost of the equipment and the duration of the measurement process are very high. ...The aim of this work is to develop a device for non-destructive measurement of specific roughness levels on stainless steel using computer vision. The device should be structurally simple, affordable, accurate, and safe for practical use. The purpose of the device is to effectively detect the level of roughness of the treated surface obtained by the water jet cutting process. On the basis of the obtained results, it is possible to adjust the parameters during the cutting process. The principle of operation of the device is based on measuring the intensity of the visible spectrum of the light reflected from the surface of the sample to be measured and correlating these values with the values of the measured roughness. After testing several variants of the device, the so-called vertical measurement variant was developed using the following equipment: violet light LED, optical filter and light splitter, USB 2.0 web camera, Arduino microcontroller, personal computer, and LabView programming interface.
The paper deals with a novel design of a combined machine tool in comparison with known contemporary analogues. It is designed for multifunctional machining of workpieces in one or two setups in ...collet and centre-to-centre design. Typical of this machine tool is the use of a bed with a trapezoidal cross-section with inclined longitudinal guides on both sides for the slides used for rough, fine and finish machining. With this design, the slides are spatially separated and lightly loaded. The material removal during roughing and finishing is separated from each other. The grinding slide and its guides are not subjected to additional thermal deflections caused by the high-temperature crisps produced during turning, and the slide for roughing and finishing is spatially protected against the influence of grinding powder. The bed meets the requirements for a thermos symmetrical design and allows internal cooling. The advantages of this arrangement from the design, technical and economic points of view are presented.
This paper describes a fast Fourier transformation and its application to monitoring tool wear. It describes the transformation of the collected signal during cutting from the time domain to the ...frequency. The introduction describes the discrete Fourier transform, DFT deficiency observed in a large number of samples. Therefore, its use in this case is fast Fourier transform. As an example, an indirect method for monitoring tool wear is shown, based on the measurement values of process variables (acoustic emission) and the relationship between tool wear and these values. Tool wear monitoring is a difficult task because many machining processes are non-linear time-variant systems, which makes them difficult to model and the signals obtained from sensors are dependent on a number of other factors, such as machining conditions.Original Abstract: U radu je opisana brza Fouriova transformacija te njena primjena na pracenje trosenja alata. Opisana je transformacija prikupljenog signala tijekom rezanja iz vremenske domene u frekvencijsku. U uvodu je opisana diskretna Fouriova transformacija, nedostatak DFT se primjecuje kod veceg broja uzoraka. Stoga svoju primjenu u ovim slucajevima nalazi brza Fouriova transformacija. Kao primjer opisana je indirektna metoda za pracenje stanja alata koja se temelji na mjerenju vrijednosti procesnih varijabli (akusticna emisija), na koje utjece vrijednost istrosenja alata. Pracenje trosenja alata je tezak zadatak, jer mnogi obradni procesi su nelinearni vremenski promjenljivi sustavi, te se kao takvi ne mogu modelirati i ti signali dobiveni iz senzora ovise o nizu drugih cimbenika, kao sto su uvjeti strojne obrade.
AlSi9Cu3(Fe) aluminium alloy is one of the most commonly used casting aluminium alloys because their utility is based on good mechanical properties. Production often leads to deviations of maximum ...levels for certain alloying elements, particularly copper. Since mechanical properties of the final products of these alloys strongly depend on the concentration of copper in the alloy, various concentrations of copper were added to the basic alloy whereas the chemical composition was monitored using an optical emission spectrometer, measuring Brinell hardness and doing tensile tests. Moreover, the impacts of copper on oxidizing and corrosion resistance of the experimental alloys were analysed. The alloy with 3 wt. % Cu showed the best results.
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