CONTROL SYSTEM OF HYDRAULIC RECOVERY MODULE OF ROAD ROLLER


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201613
J. NEVRLY1, Z. NEMEC2, J. BRANDEJS1
1Brno University of Technology, Faculty of Mechanical Engineering, Institute of Machine and Industrial Design,
Brno, Czech Republic
2Brno University of Technology, Faculty of Mechanical Engineering, Institute of Automation and Computer Science
Brno, Czech Republic

e-mail: nevrly@fme.vutbr.cz
Abstract
This paper briefly describes some features of control of the hydrostatic recovery module developed within the framework of a research project. This project was focused on research and development of a new product - a hydrostatic system for energy recovery through breaking and start-up of commercial vehicles using control for energy transfer and optimization based on mathematical modeling of the system activity.A contribution of described solution of control system of hydraulic recovery module of the road roller can be seen in the fact that this solution enabled fuel savings during recovery up to 26.6 % at low operation speed of 9 km/h.
Keywords: control, energy, recovery, hydrostatic, module
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ANALYSIS OF INFLUENCING THE MACROSTRUCTURE AND HARDNESS OF CASTING SURFACE LAYER BY CHANGING CONDITIONS OF CRYSTALLIZATION


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201720
M. KARKOVA,  J. MAJERNIK, J. KMEC
Institute of Technology and Business in Ceske Budejovice, Faculty of Technology
Ceske Budejovice, Czech Republic

e-mail: majernik@mail.vstecb.cz
Abstract
In manufacturing technology, we often encounter the demand for increasing surface hardness of the machinery components. Although there are new varied coating and surface hardening technologies, those are processes implying increasing costs, economic burden and time required for the manufacturing process including increase in production capacities, increased need for machinery and equipment, or possible dependence on external suppliers. The capability of increasing hardness of components starts in casting itself. By understanding and mastering the processes involved in the process of solidification of the melt it is possible to adjust technical parameters so that the hardness characteristics of the casting is increased by the crystallization process and thereby also by the formation of the internal structure morphology.
The article presented deals with assessing the changes in surface hardness of castings achieved by changing crystallization conditions. The issue of crystallization is addressed in terms of the processes accompanying the process of melt solidification in casting mould.   The parameters observed are macrostructure and hardness of castings fabricated using high pressure die casting technology and changes of these parameters compared to the surface hardness of the castings produced using conventional foundry technologies. At the same time, the influence of structural design of the gate on the selected parameters is observed.
Keywords: crystallization, hardness, macrostructure, high pressure die casting
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DESIGN AND CHECK OF THE MECHANICAL COMPONENTS BY THE PC APPLICATION


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201723
S. PAVLENKO
Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Technical Systems Design and Monitoring
Presov, Slovak Republic

e-mail: slavko.pavlenko@tuke.sk
Abstract
The paper focuses especially on comparison of available programs for design and check of the mechanical components. The main aim of the paper is to analyse in the introductory part the individual programs from the perspective of content and functionality and consequently to compare the results experimentally in selected cases. The paper evaluates simplicity or complexity of work with the individual software types on the basis of input requirements [Bicejova 2016a]. The conclusion summarizes the issue and experience acquired in designing and in checking of the mechanical components. 
Keywords: design, calculation, program
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DESIGN OF A MATERIAL CUTTING DEVICE WITH OPTION OF LENGTH ADJUSTMENT OF WOODEN CUTTING SUBSTANCE


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201724
J. MASCENIK
Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Technical Systems Design and Monitoring
Presov, Slovak Republic

e-mail: jozef.mascenik@tuke.sk
Abstract
The aim of the paper is a structural design of a cutting device with option of length adjustment of cutting material. The introductory part of the paper is devoted to an analysis of available devices standardly employed in the process of wooden substance cutting. The core of the paper contains structural design and calculation of the individual parts, disposition solution of the device and a complete visualisation in the 3D models[Krenicky 2010]. The final part of the paper points out a necessity of application of newly-designed devices intended for wooden substance cutting as such case offers an absolute waste less utilization of wooden substance.
Keywords: stand,cutting, splitters
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DESIGN OF A PROGRAM FOR CALCULATION OF FORCING SPRING STIFFNESS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201725
S. PAVLENKO
Technical Universtity of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Technical Systems Design
Presov, Slovak Republic

e-mail: slavko.pavlenko@tuke.sk
Abstract
The presented paper deals with a design and generation of a program for calculation of stiffness and shear stress of forcing springs. The given calculation program was generated in the program of Microsoft Office through the Excel application by means of defined sequences of the individual orders. The calculation program serves for calculation of stiffness of cylindrical and conic helical forcing springs with circular and rectangular section of wire. The designed program calculates shear stress and stiffness of the spring after entering parameter values inevitable for calculation. The program contains also a database of the standardized springs which after selection of the standardized spring assures inserting of corresponding values by means of which the program prevents a user from incorrect defining of the standardized data.
Keywords: application, stress, generation, torsion, parameters
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CRITICAL RUNNER LENGTH AS A CONSTRAINING FACTOR IN GATING SYSTEM DESIGN


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201727
J. MAJERNIK, J. KMEC, M. KARKOVA
Institute of Technology and Business in Ceske Budejovice
Ceske Budejovice, Czech Republic

e-mail: majernik@mail.vstecb.cz
Abstract
The objective of gating system design and construction process using high pressure die casting is manufacturing of castings with good mechanical and quality properties. The design must take into account various parameters, ranging from the alloy properties through technical parameters of the casting cycle to the construction of the machine and the mould dimensions. If the design of gating system is meant for an existing mould, the runner length depends on the dimensions of the mould. If the design of gating system intends to use a new mould, the runner length depends on the alloy properties, mainly on the melt solidification time when passing the gating system. The article presented deals with the maximum allowed runner length and introduce and defines the term “critical runner length”. When designing gating system for a new type of casting, measures were taken using a simulation program, in order to identify the critical runner length, on which the design of mould multiplicity and placement of casting in the mould depend. The critical runner length is defined on the basis of the maximum melt temperature at selected parts of the gating system and the proportion of solid phase in the melt. Based on the measures taken, the temperatures of the melt are described in dependence on time, heat losses are determined in dependence on the runner length and subsequently the maximum allowed runner length is determined.  The measurements, the results and conclusions described in the article are further directly implemented in the innovations of die casting in the production.
Keywords: high pressure die casting, runner, construction, solidification, simulation
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EVALUATION OF OPERATIONAL SAFETY OF CHOSEN ELECTRICAL SET ELEMENTS IN CONDITIONS OF BIOGAS PLANTS WITH USING OF INFRARED THERMOGRAPHY METHOD

                 
MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201731
P. JUNGA1, P. TRAVNICEK1, J. RUZBARSKY2
1Mendel University in Brno, Faculty of AgriSciences, Department of Agriculture, Food and Environmental Engineering
Brno, Czech Republic
2Technical University of Kosice with a seat in Presov, Faculty of Manufacturing Technologies
Presov, Slovak Republic

e-mail: petr.junga@mendelu.cz
Abstract
The paper is focused on evaluation of operational safety of chosen electrical set elements in specific conditions of agricultural biogas plants with using of infrared thermography method. The goal of the paper is thermography monitoring of the surface temperature of electrical set elements with detection of high warmed parts. Next goal is evaluation measured temperatures with criteria and requirements of standard ISO 18434-1. In terms of measurement was measured surface temperature of every element and compared with reference ambient temperature. Our study claimed suitability of IRT method for monitoring of electrical set elements. Any of measured objects has high surface temperature. This is significant risk factor for fire and related losses.
Keywords: infrared thermography, electrical set element, surface temperature, thermal defect, biogas station 
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INFLUENCE OF BETA RAYS ON POLYPROPYLENE


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201734
P. TOKLASEK, A. MIZERA, M. MANAS AND M. BEDNARIK
Tomas Bata University in Zlin
Zlin, Czech Republic

e-mail: mizera@fai.utb.cz
Abstract
The polypropylene samples for testing were injection moulded and subsequently irradiated by beta radiation at the dose of 15 and 33 kGy with the kind help of BGS Germany. Temperature stability, tensile test, bending test and Charpy-impact test were applied. The influence of beta irradiation low doses on thermal and mechanical properties was subsequently compared. Just dose of irradiation 15 kGy improves tensile and bending properties of polypropylene which expands usage of this material in new applications, especially in automotive.
Keywords: mechanical properties, tensile test, radiation cross-linking, beta rays, polypropylene and temperature stability
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INFLUENCE OF TESTING METHODS ON THE FINAL VALUES OF THE MODULUS OF ELASTICITY E


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201735
J. SOBOTKA, P. SOLFRONK, D. KORECEK, M. KOLNEROVA
Technical University of Liberec, Faculty of Mechanical Engineering
Liberec, Czech Republic

e-mail : jiri.sobotka@tul.cz
Abstract
In the area of elastic deformation there is linear dependence between the applied stress and final deformation, which is described by the Hooke´s law. Thus stress and strain are proportional to each other and constant of proportionality is termed as modulus of elasticity (even. Young´s modulus). So this material constant characterizes the elastic deformation behavior of the given material and its magnitude represents the very important material constant in all industrial branches and mainly determines the dimensions for the given parts. That is why it´s truly very important to precisely measure its values for different materials. Because of this were in this article used two methods for measurement Young´s modulus E (MPa) – static tensile test and three-point bend test. Main aim was to obtain statistical evaluation about influence of these testing methods on the final values of modulus of elasticity.
Keywords: modulus of elasticity, elastic deformation, linear fitting, material tests, slope of line, f-test, student´s t-test
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MECHANICAL PROPERTIES OF HYBRID COMPOSITES BASED ON POLYPROPYLENE MATRIX

 
MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201737
M. SEIDL, L. BEHALEK, J. HABR
Technical University of Liberec, Faculty of Mechanical Engineering, Department of Engineering Technology
Liberec, Czech Republic

e-mail: martin.seidl1@tul.cz
Abstract
The paper is focused on the analyses of the mechanical and physical properties of the hybrid composite systems based on the polypropylene matrix with implemented reinforcing cellulose fibres. The polymer phase of this conventional composites is furthermore modified by physical blowing agents, which are utilized for the formation of light microcellular structures. Interactions of all the components of these hybrid composites are evaluated in terms of density change, impact resistance, bending and tensile properties. Complying with the assumption closed pores generally decreased mechanical properties of the multiphase composite systems. The reduce of mechanical properties induced by presence of the microcellular structure was more significant with increasing level of filling by reinforcing particles.
Keywords: cellulose fibres, polypropylene, hybrid composites, physical foaming agents, mechanical properties
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MODELLING OF BIOMATERIALS PROPERTIES MAGNESIUM-BASED ALLOYS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201739
A. PANDA1, K. DYADYURA2
1Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov
Department of Manufacturing Technologies, 
Presov, Slovak Republic
2Sumy State University, Faculty of Technical Systems and Energy Efficient Technologies
Sumy, Ukraine

e-mail: anton.panda@tuke.sk
Abstract
The degradation behavior of magnesium-based alloys is obviously important for medical applications of biomaterials. Magnesium alloys were investigated as implant materials. This article critically summarizes the  in vivo knowledge and experience that has been reported on the use of magnesium and its alloys to advance the field of biodegradable metals. The efficiency of the development approach is discussed. Thermo-physical and physical properties of liquid and solid phases during solidification are critical data for simulations. However, the number of alloys for which such information is available is limited, primarily due to the difficulty in experimentally determining these properties during the casting/solidification process. This article will focus on demonstrate the value of integrating the modelling of solidification and the associated. This include show changes in the composition of an magnesium alloys  within  its specification range can substantially affect its properties during solidification and how properties of the liquid can vary significantly in the mushy zone.
Keywords: modelling, magnesium alloys, magnesium composite, biocompatibility, in vitro and in vivo corrosion, biomaterials, orthopaedics, biodegradable metallic implants
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MONITORING OF PARAMETERS DIRECTLY INFLUENCING PERFORMANCE TRANSFER BY BELT GEAR


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201741
J. MASCENIK
Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Technical Systems Design
Presov, Slovak Republic

e-mail: jozef.mascenik@tuke.sk
Abstract
The aim of the presented paper is to point out the possibilities of determination of new types of belts of the belt gear in case of a newly developed device. The developing and structural-design stage was followed by production and installation of the device. An electric motor serves as a device drive and belt gear input. The other electric motor represents a system load factor. The frequency converters diagnosed and monitored by the software intended for the purpose drive both motors. Through a simple adjustment of the designed device, diverse types and dimensions of the belts and belt pulleys can be changed. Monitoring and diagnostics of the tracked parameters was performed by the sensors fixed in the positions prescribed in advance.
Keywords: stand, belt gear, motor, diagnostics, sensor
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MONITORING THE TECHNICAL CONDITION OF THE DEVICE USING THE VIBRATION DIAGNOSTIC METHOD


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201742
S. OLEJAROVA
Technical University of Kosice, Faculty of Manufacturing Technologies
Presov, Slovak Republic

e-mail : stefania.olejarova@tuke.sk
Abstract
Vibrations are one of the important monitored parameters, which allow acquiring primary information about the operating condition of the device. It is necessary to bear in mind that vibrations of rotating machines are closely linked to the dynamic stress of the parts like bearings or transmissions. The paper is dealing with the issue of monitoring and diagnosing the size of the two based parameters of vibrations, namely speed and vibration acceleration. The experimental section presents the results of the measurement. During the processing, we have measured the size of vibration at four places and the processing was done under varying spindle rotation speed. The conclusion presents recommendations for input factors used during measuring and processing. Here you should describe the paper idea in short.
Keywords: diagnostics, technical condition, vibration parameter, speed vibration, vibration acceleration
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OPTIMALIZATION OF FUNCTIONAL PROPERTIES OF RADIAL FANS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201743
A. SMERINGAIOVA, M. WITTNER
Technical university of Kosice, Faculty of Manufacturing Technologies
Presov, Slovak Republic

e-mail : anna.smeringaiova@tuke.sk
Abstract
The article describes the process of optimizing the design of functional parts of radial fans. The main goal was to improve their performance characteristics. The proposed methodology was experimental measurements and the testing station had been built. After processing the results of the experiment the best fan construction option was chosen with optimum performance characteristics.
Keywords: fan, optimization, experimental tests, airflow, performance characteristics, delivery pressure
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SELECTION OF COMPUTATIONAL INTELLIGENCE METHODS DESIGNED FOR APPLICATION IN PNEUMATIC MUSCLE ACTUATOR


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201748
M. TOTHOVA AND M. TROJANOVA
Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov
Presov, Slovak Republic

e-mail : maria.tothova@tuke.sk
Abstract
Pneumatic muscle actuators have the highest power/weight ratio of any actuator and therefore it has a broad application prospect in soft robotics. This paper presents a two degree of freedom (2-DOF) pneumatic muscle actuator that consists of four pneumatic artificial muscles (PAMs) and two rotation joins. However, this pneumatic muscle actuator has highly nonlinear and hysteretic properties (among muscle force, muscle displacement and pressure in the muscle), which lead to difficulty in accurate position control. Pneumatic muscle actuator usually necessitate the use various nonlinear techniques for control in order to improve their performance. The paper contains selection of computational intelligence methods designed for application in pneumatic muscle actuator. There are described and compared MLP neural network and RBF neural network.
Keywords: pneumatic muscle actuator, artificial muscle, antagonistic connection, intelligence method, neural network
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SORPTION CHARACTERISTICS OF COOPER SORPTION ON THE CLINOPTILOLITE MEASURMENT


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201749
I. PANDOVA, P. ORAVEC, D. MATISKOVA
Technical University of Kosice , Faculty of Manufacturing Technologies with a seat in Presov
Presov, Slovak Republic

e-mail: iveta.pandova@tuke.sk
Abstract
Natural zeolite has found important uses in environmental protection and water treatment.In term of chemical, the zeolites belongs to hydrate aluminosilicates and against the their structure they have unique physical-chemical properties. This atribute affords the zeolites utilisation at water cleaning from metal ions. The most offen method of removing metals from solutions is precipitation, which is particularly effective at higher concentrations. In this way, but it is not always possible to reach limits that are set by law and therefore the use of zeolite is an appropriate way to final purification waste water after processing, for example. precipitation. Adsorption is among the most used and most economical method for removing cationic and anionic pollution. The possibility to use zeolites for this purpose, desirable attributes, such as high ion exchange capacity, good kinetics of ion exchange and sorption at low temperature, non-toxicity, resistance to aggressive media. Contents of this paper are the results of research on natural zeolite - clinoptilolite originating from the site in NižnýHrabovec, due to the sorption of coppercations.
Keywords: clinoptilolite, cooper, sorption, waste water
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SURFACE FINISHING OF 3D PRINTED SAMPLE MANUFACTURATED BY FUSED DEPOSITION MODELING


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201753
T. CMOREJ, A. PANDA, P BARON , P. POOR, M. POLLAK
Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov
Presov, Slovak Republic

e-mail: petr.baron@tuke.sk
Abstract
Currently, FDM (Fused Deposition Modelling) is one of the most widely used methods in field of functional prototypes of components creation in various industries. When using RepRap type of printing in some cases occurs to reduced quality of surface area of component that is located on a support, or complications when removing the supporting material. For low surface quality of components produced by using this technology it is necessary to adjust this surface, according to specific customer requirements.
The article deals with the problems of components surface post-treatment produced by FDM technology. Using standard machining methods with support and machining process simulation in Creo 3.0 software, by testing, cutting parameters and additional surface smoothing by acetone vapor bath method.
Keywords: 3D print, optimization, simulation, surface finishing
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THERMAL PROPERTIES OF IRRADIATED DURAMID WITH 45 % OF GLASS FIBRE BY BETA RAYS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201756
A. MIZERA1, P. STOKLASEK1, M. BEDNARIK1 AND Z. HOLIK2
1Tomas Bata University in Zlin
Zlin, Czech Republic

2Robert Bosch, spol. s r.o.
Ceske Budejovice, Czech Republic

e-mail: mizera@utb.cz
Abstract
DURAMID with 45 % of glass fibre (PA 9T) have been successfully modified using beta rays. PA 9T samples were prepared by injection moulding technology and then were irradiated from 33 to 198 kGy in electron accelerator RHODOTRON. The thermal properties (e.g. DSC and TGA) of modified PA 9T samples by beta rays were measured. The tested samples showed significant changes of thermal properties after irradiation. From this point of view, new applications could also be seen in areas where more expensive materials (metals, composites etc.) are used, especially for application in automotive and military industry.
Keywords: thermal properties, DSC, TGA, radiation cross-linking, beta rays, DURAMID and temperature stability
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ULTRA NANOINDENATION TEST OF INJECTION POLYBUTYLENE TEREPHTHALATE (PBT) IRRADIATED BY LOW DOSES BETA IRRADIATION


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201758
M. MIZERA, D. MANAS, M. MANAS, L. GAJZLEROVA
Tomas Bata University in Zlin
Zlin, Czech Republic

e-mail : dmanas@ft.utb.cz
Abstract
The influence of high doses of beta radiation on the changes in the structure and selected properties (mechanical and thermal) polymers were proved.  Using high doses of beta radiation for polybutylene terephthalate (PBT) and its influence on the changes of mechanical properties of ultra nanohardness has not been studied in detail so far. The specimens of polybutylene terephthalate (PBT) were made by injection moulding technology and irradiated by high doses of beta radiation (0, 33, 66 and 99 kGy). The changes in the microstructure and micromechanical properties of surface layer were evaluated using FTIR, WAXS and instrumented ultra nanohardness test. The results of the measurements showed considerable increase in mechanical properties (indentation hardness, indentation elastic modulus) when the high doses of beta radiation are used.     
Keywords: polybutylene terephthalate (PBT), microhardness, mechanical properties, ß-irradiation, FTIR, WAXS
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SQUARE SHAPED INSERT´S LIFETIME WHEN MILLING INCONEL 718


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201760
I. MRKVICA, J. PETRU, T. ZLAMAL, M. JANOS, T. SZOTKOWSKI
Technical University of Ostrava, Faculty od Mechanical Engineering, Department of Machining, Assembly and Engeineering Metrology
Ostrava, Czech Republic

e-mail : ivan.mrkvica@vsb.cz
Abstract
This article is focused on the analysis of tool wear in milling of Inconel 718. Inconel 718 is tough and highly temperature resistive material, which is used due to its excellent properties especially in aggressive corrosive environment. Machining of this alloy is still complicated. The feasibility of three inserts tested for milling of Inconel 718 has been shown in this work. Different cutting speeds and feeds were used. Experimental tests were performed in order to analyze wear evolution. It was found that cutting conditions and type of insert strongly affects tool wear mode. Surface roughness was studied as well as cutting force as a function of tool wear.
Keywords: milling, Inconel 718, cemented carbide, lifetime, cutting inserts
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PARAMETERS INFLUENCING THE PRECISION OF VARIOUS 3D PRINTING TECHNOLOGIES


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201776
P. MANTADA, R. MENDRICKY, J. SAFKA
Technical University of Liberec, Department of Manufacturing Systems and Automation
Liberec, Czech Republic

e-mail: phaneendra.mantada@gmail.com
Abstract
This article focuses on parameters that influence production of parts by different 3D-printing technologies (FDM, Polyjet Matrix, SLA and SLS). This article acquaints its readers with data and results of research dealing with influence of production process parameter settings on the magnitude of internal material tension of the printed part, or its influence on dimension and shape precision of products manufactured by these technologies. The samples may change their properties by change in time so we are inspecting all the printed samples and analyse the dimensional and shape accuracy of each sample in three time frames (0 days, 14 days and 84 days). The produced samples were measured and their shape precision was analysed by Optical 3D contactless scanners and therefore perform shape and dimension precisions of the produced prototypes in a complex and objective manner and the effect of "aging" was researched using GOM inspect professional.
Keywords: 3D Print, fused deposition modelling, polyjet matrix, stereolithography, selective laser sintering, 3D optical scanner, 3D digitization
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ASPECTS OF THE INVESTIGATION OF THE DYNAMIC BEHAVIOUR OF MACHINE TOOLS BY OPERATIONAL MODAL ANALYSIS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201777
J. BERTHOLD1, M. KOLOUCH2, V. WITTSTOCK1 AND M. PUTZ2
1Chemnitz University of Technology, Institute for Machine Tools and Production Processes
Chemnitz, Germany
2Fraunhofer Institute for Machine Tools and Forming Technology IWU
Chemnitz, Germany

e-mail: jan.berthold@mb.tu-chemnitz.de
Abstract
There are differences in the dynamic behaviour of a machine tool between standstill and process because of preloads, process damping and gyroscopic moments. The standard method to characterize the dynamic behaviour, the experimental modal analysis (EMA), is performed only in the standstill and neglects these effects. In contrast, operational modal analysis (OMA) makes possible a characterisation of the dynamic behaviour under working conditions. Nevertheless, the performance of OMA is based on some assumptions. In this paper several key aspects considering these requirements regarding to machine tools are discussed. These presumptions affect the time-invariance during the measurement, the suitability of a milling process to excite the machine adequately and the influences of the different identification methods to the results. The obtained results of these investigations will be used in further studies to make OMA applicable for machine tools.
Keywords: machine tool, operational modal analysis, dynamics, excitation, cutting forces, identification
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REPRODUCIBILITY OFTHERMAL ERROR BEHAVIOUR IN MACHINE TOOLS FROM THE SAME MODEL TYPE


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201779
P. MINAR, T. GREGOR
Intemac Solutions, s.r.o.
Kurim, Czech Republic

e-mail: minar@intemac.cz
Abstract
The present paper deals with predictive modelling of thermal deviation of the machine tool due to thermal deformations. Thermal deformation of the machine tool structure is one of the basic problems that need to be addressed when increasing the accuracy of machine tools. For each particular machine tool, it is necessary to measure its behaviour, evaluate it, and, based on the acquired knowledge, create compensation functions, which is time consuming. This study is concerned with whether it is possible to reproduce a compensation model created for one particular machine tool on the machine tools of the same production series. A reproducibility of the model was examined on two machine tools. Temperature measurements were performed at different machine tool locations along with the positioning of the tool centre point (TCP). A regression analysis was used to find the relationship between the temperature on the components and the observed change of TCP position. A method of calculating linear regression coefficients of a regression model has been defined. Furthermore, a predictive capability of the regression model among the manufactured machine tools was compared based on the size of the data set and whether the model can also be reproduced under different ambient conditions.
Keywords: machine tool, ambient environment, thermal behaviour, error prediction, linear regression model, compensation
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CORRELATION BETWEEN DYNAMIC PROPERTIES OF LINEAR GUIDE AND RADIAL FORCE LOAD


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201780
J. STETINA, Z. FIALA
INTEMAC Solutions, s.r.o.
Kurim, Czech Republic

e-mail: stetina@intemac.cz
Abstract
A dynamic behavior of machine tools always depends on dynamic properties of machine tool individual parts; for example, a spindle unit, frame, ball screw, linear guide, etc.  The present paper deals with an analysis of dynamic properties of linear guide RA55AN. The guide was fixed to a special testing stand which enabled us to change and measure radial force loads of the linear guide via a thread mechanism and a force washer. The aim of this article is to define the correlation between the value of radial force load and the linear guide dynamic properties. A dynamic compliance and modal analysis were used as criteria for evaluation of linear guide dynamic properties.
Keywords: modal analysis, natural frequency, damping, linear guide, force load, dynamic compliance
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NOISE AND STEP HEIGHT PERFORMANCE OF SELECTED OPTICAL SURFACE MEASURING INSTRUMENTS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201781
M. HARCARIK, R. JANKOVYCH
Brno University of Technology, Faculty of Mechanical Engineering, Institute of Production Machines, Systems and Robotics
Brno, Czech Republic

e-mail: matej.harcarik@vutbr.cz, jankovych@fme.vutbr.cz
Abstract
Increasing demands for manufacturing quality and new standards in surface metrology foreshadow a widespread adoption of 3D surface topography measurement in manufacturing quality control. This raises the question of instrument selection. Coherence scanning interferometry and laser scanning confocal microscopy are some of the most common technologies in optical measurement of surface topography. These methods differ significantly in their suitability for different types of measurement. This article provides a comparison of the measurement noise and step height measurement performance two measuring instruments based on these two principles in relation to objectives used for measurement. Such data can be used to inform instrument selection in an industrial environment.
Keywords: surface texture, confocal microscopy, coherence scanning interferometry, comparison of instruments, topography measurement noise, step height repeatability
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AUTOMATIC STRAIGHTENING OF HARDENED SHAFTS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201782
R. JANKOVYCH, M. WEIGL, B. KUR
Brno University of Technology, Faculty of Mechanical Engineering, Institute of Production Machines, Systems and robotics
Brno, Czech Republic

e-mail: martin.weigl@mesing.cz, jankovych@fme.vutbr.cz
Abstract
The main purpose of this article is to present a new way of straightening hardened shafts. The straightening of regular shafts is usually not difficult, but the situation is very different in case of hardened shafts. The regular shafts are usually straightened by bending of the shaft in the opposite direction than the original deformation. Sadly, this approach cannot be applied on hardened shafts, because of the brittleness of highly hardened material. Mesing Ltd. in cooperation with Brno University of Technology are now trying to automate the process of straightening by changing the stress inside of the hardened material. This method uses controlled impacts of a ram on the surface of the shaft which has to absorb the energy of the ram. The impact causes a plastic deformation of the surface of the shaft and changes the inner stress. At the end of this article is the design of such measuring and straightening setup shown and described.
Keywords: dynamic measuring, hardened shafts, straightening ram, textile spindle, internal stress of hardened parts
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USE OF THE LCC ANALYSIS TO SELECT A TECHNICAL SOLUTION OF POWER DRIVE FOR APPLICATION AT RAILWAYS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201783
E. SUJOVA, H. CIERNA
Technical University in Zvolen, Faculty of Environmental and Manufacturing Technology, Department of Manufacturing Technology and Quality Management
Zvolen, Slovak Republic

e-mail: erika.sujova@tuzvo.sk
Abstract
The paper addresses identification and analysis of individual costs of a life-cycle of engines for railways that meet required emission limits according to STAGE III.B.A cost analysis ofa life-cycle is an effective tool, which allows for observation of various options of technical solutions. The result of an LCC analysis is the basis on which a decision is made about selecting a technical solution of power drive of locomotives and efficiency of the solution with one or three combustion engines. The result is also preparation of a life-cycle costs identification method for specific locomotive engines and initial evaluation of advantages, specifically disadvantages of the solution.
Keywords: costs, life-cycle costs (LCC), locomotive engine, power drive
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ANALYSIS OF LOW FREQUENCY MAGNETIC FIELDS GENERATED DURING WELDING


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201784
J. GLATZ, M. GORZAS, Z. KOTIANOVA
Technical University of Kosice, Faculty of Mechanical Engineering, Department of Safety and Quality
Kosice, Slovak Republic

e-mail: juraj.glatz@tuke.sk, michal.gorzas@tuke.sk, zuzana.kotianova@tuke.sk
Abstract
The topic of the impact of electromagnetic fields on human body is nowadays very actual. One of the physical factors of the work environment is the electromagnetic fields emitted by the electric devices. The effect of electromagnetic fields on human body is various and depends mainly on frequency and intensity. Electromagnetic fields create a wide range of resources with which the workers can meet in their workplace. They are developed and used in many work activities including manufacturing processes, research, communication, medical applications, production, transmission and distribution of electricity, broadcasting, aviation and maritime navigation and security. This contribution describes the impact of electromagnetic fields on human body during welding. The shape and intensity of the generated electromagnetic fields were measured by a three-axis magnetometer.
Keywords: safety, low frequency magnetic field, employee
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EFFECT OF TOP COVER SHAPE ON ENERGY DEMANDS AND WORKSPACE PRESSURE OF MULCHER


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201785
J. CEDIK1, J. CHYBA2, M. PEXA1, S. PETRASEK2
1Czech University of Life Sciences Prague, Faculty of Engineering, Department for Quality and Dependability of Machines
Prague, Czech Republic
2Czech University of Life Sciences Prague, Faculty of Engineering. Department of Agricultural Machines
Prague, Czech Republic

e-mail: cedikj@tf.czu.cz
Abstract
Mulchers with vertical axis of rotation are highly energy demanding machines and it is expedient to increase their effectiveness. The paper deals with evaluation of the effect of the shape of mulcher’s workspace cover on energy demands and pressure conditions of the workspace of mulcher with vertical axis of rotation. The pressure conditions inside the workspace are connected with the airflow which is vital for the correct function of the machine. The laboratory model of one mulcher’s rotor was used for the measurement. Three workspace cover shapes were used for the measurement, including shapes called “drop”, “toroid” and flat cover which was used as a reference. The measurement was carried out at cutting speeds of 21, 42, 63, 84 and 105 ms-1. The proposed shapes of mulcher’s workspace cover showed higher energy demands, while the cover in shape “toroid” significantly affected the pressure profile in the mulcher workspace.
Keywords: mulcher, energy demands, pressure conditions, workspace cover, energy losses
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HAMMER PEENING WITH A PIEZO-ACTUATED TOOL FOR SURFACE FINISHING


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201786
M. KOLOUCH, M. WABNER AND R. KURTH
Fraunhofer-Institute for Machine Tools and Forming Technology IWU
Chemnitz, Germany

e-mail: martin.kolouch@iwu.fraunhofer.de
Abstract
Low roughness of free-form surfaces represents a challenge in production of forming tools. In the industry, the free-form surface is grinded and polished manually. The technology of hammer peening has the capability to replace the time consuming handcraft by automated machining with high productivity and other positive effects, like increased hardness and compressive residual stress in the surface layer. This leads to a high wear resistance of the machined surface. The hammer peening can be conducted with a piezo-actuated tool. The high frequency of such a tool allows achieving higher productivity than other actuator principles used in hammer peening tools. In this paper, a piezo-actuated hammer peening tool working in its mechanical resonance is presented. Furthermore, a cross-domain model including the process, the mechanical and the electrical part of the tool is explained. This model is further used for optimization of the process and the tool. The functionality of the tool is demonstrated by machining results.
Keywords: finishing, dynamics, piezoelectric, simulation, hammer peening
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IDENTIFICATION OF SAFETY CULTURE LEVEL USING QUESTIONNAIRE SURVEYS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201787
I. FEDORYCHEVA, M. HAMMER
Brno University of Technology, Faculty of Mechanical Engineering
Deptartment of Quality, Reliability and Safety, Institute of Production Machines, Systems and Robotics
Brno, Czech Republic

e-mail: Irina.Fedorycheva@vutbr.cz
Abstract
The aim of the present article is to provide information on the results of the safety culture assessment carried out in three engineering companies in the Czech Republic in 2017. Determining the level of safety culture helps to reveal the weaknesses in the work process from the point of view of safety in a particular company and, of course, it also allows to propose the necessary measures for improvement.
The article builds on the previous publications of the authors; therefore, it no longer announces the theoretical essence of the safety culture, but addresses the practical aspects of the subject based on factual examples. The article has two main parts. First, the issue of investigating the safety culture is described, including one of the selected approaches. The principles and techniques of questionnaire processing are analysed. The next part of the article introduces the results of the assessment.
The issues of safety culture are quite extensive; it is not possible to tackle all of them in a single article. In some areas, the safety culture is not systematically addressed in its complexity. This also applies to engineering. In our workplace, we intensively focus on the issues of safety culture; some partial approaches and results are the content of the present article.
Experience with the described assessment method can be useful or serve as a guide to analyse the level of safety culture in other industrial companies.
Keywords: safety culture characteristics, questionnaire construction, safety performance, safety culture assessment
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CALIBRATION OF PHOTOMETER-BASED DIRECT-READING AEROSOL MONITORS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201788
M. DADO1, L. MIKUSOVA1, R. HNILICA1, A. OCKAJOVA2
1Technical University in Zvolen, Faculty of Environmental and Manufacturing Technology, Department of Production Engineering and Quality Management
Zvolen, Slovak Republic
2Matej Bel University, Faculty of Natural Sciences, Department of Technology
Banska Bystrica, Slovak Republic

e-mail: miroslav.dado@tuzvo.sk
Abstract
All photometer-based direct-reading aerosol monitors use the principle of the light scattering to determine airborne particle concentration. Most photometers are calibrated in the factory using a „standard test dust” and are adjusted to agree with respirable dust concentration measurements made using reference gravimetric methods. In practice, it is highly unlikely that the „standard” test dust will exhibit the same physical properties (refractive index, density, particle size distribution, shape) as the airborne particles being measured. In order to obtain an accurate measure of airborne particle concentration, the aerosol monitor should always be compared to a reference gravimetric dust sampler placed alongside and adjusted accordingly. This study conducted controlled experiments to compare the measurements of real-time time photometers with gravimetric mass. Particulate matter source tested was wood-dust generated by handheld sanding operation.
Keywords: photometer, correction factor, airborne particle concentration, gravimetric reference, sampling system
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STUDY OF WEIGHTED MULTILATERATION IN VOLUMETRY OF CNC MACHINE TOOLS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201789
B. NAVRATILOVA, L. KOKRDA
Brno University of Technology, Faculty of Mechanical Engineering
Brno, Czech Republic

e-mail: 115877@vutbr.cz
Abstract
This paper describes utilization of a multilateration principle in the multi axis machine error modeling. Multilateration plays an important role in the identification of the exact position of the point in a machine tool workspace. The measured data were obtained using laser tracer in spherical coordinates. The multilateration attempts to improve the data accuracy using only a radial component. Two approaches are presented: the multilateration without weighing and the multilateration with weighing. That is based on the quality of the laserTRACER signal during the measurements. The weight of each value of the measured distance was given as a ratio of each signal quality to the best signal quality which was obtained during the measurement. Both of our results were compared to the data that were obtained by the original software TRAC-CAL.
Keywords: accuracy of measurement, multilateration, weighted multilateration, machine tool, LaserTRACER
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SELECTED CHARACTERISTICS AND DIAGNOSTICS OF MOTOR POWERED BY FREQUENCY CONVERTER


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201790
P. NAHODIL, M. HAMMER
Brno University of Technology, Faculty of Mechanical Engineering
Brno, Czech Republic

e-mail: petr.nahodil@siemens.com 
Abstract
All of the technical devices that are powered by the frequency converter, apart from their great advantages, also bring considerable pitfalls and risks. When designing a machinery, it is necessary to consider the negative effects of characteristics of the frequency converter on the rotating parts, especially on the bearings of motors, gearboxes, gears, seals, etc. These devices and their parts are usually exposed to the effects of capacitive and shaft currents that have a considerable impact on the reliability of machines and equipment. This article focuses on the reasons for the use of insulated bearing (or insulated coupling) for asynchronous motors and on the influence of the measures taken to eliminate the adverse effects on the rotating parts. The following is an example of the use of technical diagnostics to determine the condition of some parts of the machinery, the example is evaluated, conclusions are drawn and analysed.
Keywords: frequency converter, parasitic current and voltage, shaft voltage, capacitive current, technical diagnostics, FFT spectrum of vibrations acceleration, vibro-diagnostics
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APPLICATION ON-THE-FLY MEASUEREMENT OF CNC MACHINE TOOLS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201791
M. HOLUB, J. VETISKA, F. BRADAC, M. VALA
Brno University of Technology, Faculty of Mechanical Engineering
Institute of Production Machines, Systems and Robotics, Deptartment of Production Machines
Brno, Czech Republic

e-mail:holub@fme.vutbr.cz
Abstract
The publication describes an on-the-fly tracking experiment using a self tracking interferometer on a small three-axis machining center. On-the-fly based on continuous measurement, you can get much more measured points while reducing the time required for machine tool calibration than using Trigger or time measurements. The present publication compares the time required for calibration of the machine, and compares measured and evaluated data with each other. At the end the results are presented for calibration and verification of volumetric compensation with self tracking interferometer. In addition, the results obtained were verified by a circular test ISO 230-4.
Keywords: machine tool, compensation, geometric accuracy, volumetric accuracy, tracking interferometer
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USE OF MULTIPARAMETRIC DIAGNOSTICS IN PREDICTIVE MAINTENANCE


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201792 
H. OPOCENSKA, P. NAHODIL, M. HAMMER
Brno University of Technology, Faculty of Mechanical Engineering
Brno, Czech Republic

e-mail: opocenska@fme.vutbr.cz, petr.nahodil@seznam.cz, hammer@fme.vutbr.cz
Abstract
The present article describes how to use multiparametric diagnostics in maintenance. First, the maintenance is defined and its history is briefly analysed. Subsequently, the maintenance is divided according to current considerations. It is stated that the proactive maintenance represents the state-of-the-art approach to maintenance management. The use of multiparametric diagnostics, such as vibration analysis, electrodiagnostics, tribodiagnostics, etc., is mentioned. A special attention in the present article is paid to the examples of the use of diagnostics in dynamic and static measurements. The so-called route diagnostics focusing on vibrations, as well as diagnostics of current and voltage values, power input monitoring, spectral analysis of current, and temperature, flow and pressure measurements are mentioned. The measurements of insulation resistance and other parameters of the device drive are also given. The text is supplemented with several pictures showing the results of specific diagnostic measurements from industrial practice.
Keywords: predictive maintenance, vibration analysis, multiparametric diagnostics, trending of broadband vibration values, insulation resistance, polarization index, winding impact test
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DIAGNOSTICS AND MAINTENANCE OF MACHINE TOOL SPINDLES- NEW VIEWS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201793 
O. HOLUB, M. HAMMER
Brno University of Technology, Faculty of Mechanical Engineering
Brno, Czech Republic

e-mail: 145399@vutbr.cz , hammer@fme.vutbr.cz
Abstract
This paper discusses changes in the field of maintenance brought by the Fourth Industrial Revolution - Industry 4.0. Main pillars of the Industry 4.0 are as follows: digitization, interconnection, linking and visualization of all corporate parts, starting from production, through maintenance, and ending by logistics.
Maintenance is one of the areas affected most by these changes. It is not enough to monitor only certain machine parameters and assess their status –the offline diagnostics. Monitoring of all machines and measurable parameters is requested and, in addition to it, it is advisable to ensure visualizationfor the users –the online diagnostics.
Technical diagnostics belongs to important aspects for ensuring maintenance, mainlythe preventive, predictive and proactive maintenance. Vibrodiagnostics is one of the most widespread diagnostics in the field of mechanical engineering, where the signal from the source of vibrations carries the information concerning the cause of vibrations, and its analysis can establish, even well in advance, the emerging or developing defect or damage.
This article describes the differences between the online and the offline vibrodiagnostics and analyzes the results of specific measurements. Online diagnostics visualization with the possibility of its use in the maintenance sector is demonstrated here as well.
Keywords: industry 4.0, maintenance, technical diagnostics, offline- online diagnostics, vibrodiagnostics, visualization
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PROGNOSIS OF BEHAVIOUR OF MACHINE TOOL SPINDLES, THEIR DIAGNOSTICS AND MAINTENANCE


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201794
A. MOSYURCHAK, V. VESELKOV, A. TURYGIN, M. HAMMER
Brno University of Technology, Faculty of Mechanical Engineering
Brno, Czech Republic

e-mail: xmosyu00@vutbr.cz,veselkov.v@gmail.com, turygin.andrey@gmail.com,hammer@fme.vutbr.cz
Abstract
The present article focuses on the use of neural networks to predict the behaviour of certain diagnostic parameters of spindles of machine tools. An online vibro-diagnostics is used, and from many specific measured parameters, the effective value of some variables in the time series. The results are used in the maintenance based on the technical condition, in particular, in preventive and proactive maintenance. This procedure is completely original and allows for better setting of maintenance policy, which is also beneficial for planning maintenance costs. The article also mentions the necessity to implement the steps described, also in the context of the Industry 4.0 initiative, and further, it briefly discussesprognostics, technical diagnostics, maintenance and maintenance systems. The used neural networks and the calculation procedure are also analysed. The conclusions obtained are evaluated.
Keywords: neural networks, prognosis of diagnostic parameters behaviour, machine tool spindle, preventive and proactive maintenance, maintenance system, Industry 4.0
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OPTIMISATION OF WEDM SETTINGS PARAMETERS WHEN MACHINING PURE ALUMINIUM USING THE DOE


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201795
K. MOURALOVA, J. KOVAR, T. PROKES, J. BEDNAR, P. HRABEC
Brno University of Technology, Faculty of Mechanical Engineering
Brno, Czech Republic

e-mail: mouralova@fme.vutbr.cz
Abstract
The unconventional wire electric discharge machining technology (WEDM) is widely used in many industries, which is why there is a permanent emphasis on increasing the quality of suchmachined surface. The aim of this study was to carry out a design of experiment (DoE) to reduce the surface qualit yparameter Pq. During the 33-round experiment, the input factors – machine setting parameters, such as gap voltage, pulse on time, pulse off time, wire speed, and discharge current, were changed. Subsequently, Pq – root mean square deviation of the primary profile and Pa – arithmetic average of the primary profile were evaluated on the machined surfaces of pure aluminium. By using DoE, the setting of the machine’s parameters was designed in order to achieve the highest possible surface quality.
Keywords: WEDM, electrical discharge machining, Design of Experiment, P-parameters, root mean square deviation of the primary profile Pq, pure aluminium
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USING WEDM TO MACHINE A PURE MOLYBDENUM WELDING ELECTRODE


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201797
K. MOURALOVA1, R. ZAHRADNICEK2, R. HRDY2
1Brno University of Technology, Faculty of Mechanical Engineering
Brno, Czech Republic
2Brno University of Technology, Faculty of Electrical Engineering and Communication,
Brno, Czech Republic

e-mail: mouralova@fme.vutbr.cz
Abstract
Materials and elements with a high melting point, including molybdenum, are suitable for high temperature physical applications and the fabrication of components such as welding electrodes or wires to be used in spark erosion wire-cut machines. The classic, or conventional, approaches to machining pure molybdenum are aptly complemented with the frequently used unconventional wire electrical discharge machining (WEDM) method. This paper proposes a detailed analysis of a WEDM-machined surface and its defects, as related to a welding electrode. Comprehensive information  on the topography, including a 3D color-filtered representation of the surface, was acquired using a contact profiler and an atomic force microscope (AFM). The defects of the machined surfaces were examined with electron microscopy, both directly on the surface of a given sample and within its cross section. The entire set of associated processes also involved a local analysis of the chemical composition of the subsurface layer and a measurement of the relevant hardness.
Keywords: WEDM, electrical discharge machining, pure molybdenum, topography of surface, electrode for welding
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SAFETY OF THE WATER SUPPLY SYSTEM IN THE ABSENCE OF DESINFECTION RESIDUE


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201798
J. RUCKA, M. RAJNOCHOVA
Brno University of Technology, Faculty of Civil Engineering, Institute of Municipal Water Management
Brno, Czech Republic

e-mail: jan.rucka@vut.cz
Abstract
The paper focuses on the drinking water supply with public water mains without the use of disinfectant residues in the transported water. This method of delivering drinking water can only be considered if a sufficient number of functional barriers are present in the distribution system to prevent the penetration of pollution into the transported water. One of these barriers is, for example, a good technical condition of the water-supply system. The security of water supply without disinfectant is ensured by an initial assessment of the suitability of the water system for this mode of operation, risk analysis and network monitoring in selected critical points of the system.
Keywords: chlorine, disinfectant residue, water supply, undesired event, risks analysis
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POSITION-DEPENDENT RESPONSE SIMULATION OF MACHINE TOOL USING STATE-SPACE MODELS


MM (Modern Machinery) Science Journal, December_2017
DOI: 10.17973/MMSJ.2017_12_201799
F. KSICA, Z. HADAS
Brno University of Technology, Faculty of Mechanical Engineering
Brno, Czech Republic

e-mail:Filip.Ksica@vutbr.cz
Abstract
The stability of a machining process is a function of the dynamic response between the spindle and table, which varies within the machine work volume. This paper deals with computationally efficient methodology to evaluate and simulate dynamic performance of the machine tool. A position-dependent virtual model is assembled using finite element model reduced via component mode synthesis and transformed to a state-space multi-input-multi-output system. Combination of these techniques allow time-efficient response simulations with significantly less computational effort than conventionally used full finite element models. The presented approach can be used to create position-dependent dynamic stiffness map within the work volume used to predict and reduce unstable behaviour during operation. Furthermore, these techniques are not reserved for machine tools exclusively and can be used in wider spectrum of technical applications, that require time-efficient response simulations.
Keywords: machine tool, virtual model, component mode synthesis, state-space model, response simulation, position-dependent stability
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