CONCEPT OF OPTIMIZATION AND DESIGN OF A TESTING DEVICE FOR TESTING SEPARATING GRILLES

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201825
NAQUIB DANESHJO1, MILAN MAJERNIK1, ERIKA DUDAS PAJERSKA1, MIRWAJS DANISHJOO2
1University of Economics in Bratislava, Faculty of Business Economics with seat in Kosice, Kosice, Slovak Republic
2Enter price, Fredericksburg Rd Apt San Antonio, San Antonio, Texas, United States of America (USA)

e-mail: daneshjo47@gmail.com
Abstract
The paper deals with a basic design of testing device for testing of separating grilles. It describes a physical principle of particle separation using this grille. It deals with a basic physical-design solution of this device. The device simulates environmental conditions while driving a vehicle and provides a customer with data on separation efficiency of the tested grille.
Principally, similar tests can be carried out in aero or automobile aerodynamic tunnels where environmental impacts (rain, snow, dust particles, formation of an aqueous aerosol) cannot be applied. Any application of these effects in the test would result in aerodynamic laboratory pollution and a large financial increase in a course of the test.
Keywords: testing device, force sediment separator, separating grilles, principle of testing, CAD/CAM, simulation, structural 3D modellers
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INVESTIGATION OF AN ELEVATOR DISPATCHER SYSTEM

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018028
JAMIL AHMAD1, MUHAMMAD LATIF1, PETR HOREJSI2
1School of Engineering, Manchester Metropolitan University, UK
2Faculty of Mechanical Engineering, University of West Bohemia, Pilsen, Czech Republic

e-mail: tucnak@kpv.zcu.cz
Abstract
To provide an efficient elevator system, a variety of diverse and sometimes conflicting constraints have to be solved. This paper focuses on using discrete event simulation as a means to model and explore elevator dispatching strategies. Witness simulation software has been used as a test-bed for model building, simulation and some experimentation. Model building using Witness model elements is described in detail followed by two different elevator call strategies. The main steps in the methodology are described with reference to a single elevator servicing a five-storey office building. The elevator call strategies are simulated and results compared. It was found that the data set significantly skews the results and overshadows any efficiency gains that might be possible from the different dispatching strategies. The paper concludes with the need to carefully select the data set as the basis for simulation comparisons and outlines future work required.
Keywords: elevator dispatcher system, simulation, witness, sequence dispatcher, shortest travel distance, most different destinations
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APPLICATION OF A BALLBAR FOR DIAGNOSTICS OF CNC MACHINE TOOLS

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018032
MICHAL HOLUB, FRANTISEKBRADAC, ZDENEK POKORNY, ADAM JELINEK
Faculty of Mechanical Engineering, Brno University of Technology, Brno, Czech Republic
e-mail: holub@fme.vutbr.cz
Abstract
This paper describes the possibilities of using the Ballbar QC20-W diagnostic tool for long-term monitoring of geometrical accuracy of CNC machine tools. By introducing regular checks, the production capability and the planned machine maintenance should be increased. The publication presents the results obtained from a case study. The case study describes the procedures and results of introducing a regular inspection into the manufacturing process at the MCV 754QUICK (KOVOSVIT-MAS) three-axis machining center are presented to use statistical tools for long-term machine condition monitoring.
Keywords:machinetool, diagnostic, geometric accuracy
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MODIFICATIONS TO THE EFFECTOR FOR MEASUREMENT OF GRIPPING FORCE

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018100
JIRI SUDER, MILAN MIHOLA, ZDENEK KONECNY, TOMAS KOT, ROBERT PASTOR
VSB - Technical University of Ostrava, Department of Robotics, Ostrava, Czech Republic
e-mail: jiri.suder@vsb.cz
Abstract
The article describes modifications to the effector of a manipulator arm proposed in order to increase the accuracy of jaw force measurements. Gripping force measurement is performed using strain gauges. Their proper positioning and connection minimize not only the influence of the position of the centre of gravity of the manipulation object on the jaws but also the effect of temperature changes around the measuring area. The possibility of altering the magnitude of gripping force was incorporated into the robot control application. This greatly increases the security of handling and increases the number of items that can be possibly gripped. Modified effector parts were subjected to stress analysis, with emphasis on the elimination of stress peaks that would not occur in real parts. The article also describes the design of the mechanical modification of the effector, which would allow the continuous rotation of the jaws of the effector.
Keywords: measurement of gripping force, effector, straingauge, manipulator arm, stress analysis
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SIMULATION MODEL OF POLYCARBONATE MATERIAL FOR ADDITIVE TECHNOLOGY FDM

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018101
JAN LIPINA1, VACLAV KRYS1, PAVEL MEC2
1Department of Robotics, Faculty of Mechanical Engineering, Ostrava-Poruba, Czech Republic
2Department of Building Materials and Diagnostics of Structures, Faculty of Civil Engineering, Ostrava-Poruba, Czech Republic

e-mail: jan.lipina@vsb.cz
Abstract
The Department of Robotics at the VSB-TU Ostrava has been long-term involved in the improvement of parameters in parts produced by additive technology. It primarily concerns component parts as well as bigger functional units of mobile robots. However, it is not exceptional to produce a complete bearing frame of a mobile robot or an effector with the majority of parts produced by additive technology. This paper follows up previous publications from the area of material properties of “printed” polycarbonate, where, on the basis of tensile and bend tests, basic mechanical properties of printed polycarbonate were verified. Based on these paper-described performed tests, values have been acquired and subsequently a simulation model for the above-material has been designed. The simulation model and found out mechanical properties of the material should primarily serve to designers at the phase of drafting parts or functional units produced by additive technology FDM.
Keywords: rapid prototyping, polycarbonate, bend tests, tensile tests, shear tests, simulation model
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USE OF DIFFERENT SIMULATION METHODS FOR DESIGN OF EXPERIMENTAL ROVER

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018102
ROBERT PASTOR, ALES VYSOCKY, PETR SIROKY, ZDENEK KONECNY, LADISLAV KARNIK
Vysoka skola banska - Technicka univerzita Ostrava, Faculty of Mechanical Engineering, Department of Robotics, Czech Republic
e-mail: ales.vysocky@vsb.cz
Abstract
In this study results of various simulation methods are evaluated used for design of experimental prototype rover. The proposed rover must satisfy requirements for operation in specific conditions. Simulation environment of V-REP software is used for verification of proper functionality of kinematics of the rover and for the draft of fundamental parameters. Deformation of beams are simulated in the Structure module of the software product PTC Creo and suspension system is verified in the Mechanics module in this software. By the application of simulations in the design process of experimental rover, possible problems can be detected before prototype production. The advantage is that behavior of several kinematic structures can be compared and evaluated their characteristics. By matching combinations of simulation tasks, some important parameters can be verified by multiple methods.
Keywords: rover, simulation, kinematics, suspension system, FEM analysis
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PROCESSING AND VISUALIZATION OF MICROCLIMATIC DATA BY USING VIRTUAL REALITY

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018104
JIRI KROUPA1, ELISKA TUMOVA2, ZDENEK TUMA1, JIRI KOVAR1, VLADISLAV SINGULE1
1Brno University of Technology, Faculty of Mechanical Engineering, Brno, Czech Republic
2Brno University of Technology, Faculty of Civil Engineering, Brno, Czech Republic

e-mail: kroupa@fme.vutbr.cz
Abstract
The appropriate way of measured data visualization is an important factor which has a significant impact to its quality as well as to the speed of the data analysis. Especially when the analysis is carried out by a multidisciplinary team. The virtual reality is one of the techniques used for data visualization. It is progressive technology which enables better and faster understanding to visualized data. In this paper it is described a platform based on the database system for a data combined with their representation in virtual reality. The platform is designed for storing and visualization of microclimatic data from indoor spaces and climatic data from corresponding outdoor locations. Measured data are transmitted over the Internet to the database and they are visualized by an application which is created using Unity3D engine. The resulting application is suitable as a tool for monitoring and direct regulation of internal microclimate by user.
Keywords: virtual reality, virtual environment, database system, visualization, microclimatic data
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A SUBSTRUCTURING APPROACH FOR SIMULATION OF TIME DEPENDENT WORKPIECE DYNAMICS DURING MILLING

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018105
CHRISTIAN BRECHER, PRATEEK CHAVAN, ROBERT SPIERLING, MARCEL FEY
Laboratory for Machine Tools and Production Engineering (WZL) of RWTH Aachen University, Aachen, Germany
e-mail: p.chavan@wzl.rwth-aachen.de
Abstract
During milling, the process forces and poor dynamics of the machine may lead to undesirable vibrations between workpiece and tool. The magnitude of these vibrations and the chatter tendencydepends mainlyuponthe dynamic properties of the Tool-Machine-Workpiece system. The dynamic properties of the workpiece can vary significantly during the cutting process, while removing a large volume from a workpiece. Therefore, the aim of this paper is to enable the simulation of time dependent workpiece dynamics by considering its state of material removal.
A method is proposed to incrementally modify the Finite Element (FE) model of the raw workpiecedepending on the volume of removed material obtained by a tool-workpiece penetration simulation, such that an FE model of the intermittent machined state is obtained. This is realized by substructure decoupling in the physical domain. The time-varying dynamic model of the workpiece is thencoupled at four points to spring elementsrepresenting the stiffness of the machine tool table. The developed simulation is subsequently verified by means of vibration measurements and milling tests on a reference workpiece.
Keywords: workpiece dynamics, dynamics substructuring, physical domain, milling
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THE CARRYING CAPACITY OF TiCN COATING ON CONVEX-CONCAVE (C-C) GEARINGS

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018107
ERNEST GONDAR1, MIROSLAV BOSANSKY2, JANA REPKOVA1, FRANTISEK TOTH3
1Institute of Institute of Technology and Materials
2Institute of Transport Technology and Design, Slovak University of Technology in Bratislava
3Department of Machine Design Faculty of Engineering, Slovak University of Agriculture in Nitra, Slovak Republic

e-mail: miroslav.bosansky@stuba.sk
Abstract
This paper discusses the possibility of increasing the surface load capacity in C60E steel gearings by applying selected thin coatings. It describes the effect of tribological characteristics, such as friction coefficient, wear, adhesion and hardness of  TiCN coating on convex-concave gearing (C-C).  The average thickness of  TiCN  is 3.3µm. Delamination of the TiCN coating was recorded at a load of approximately 50 N. The friction coefficient of TiCN was 0,18. The nano-hardness of the TiCN coating was 41.8 GPa. The results of the tests on C-C gearings on the Niemann  tester show that the TiCN coating deposition occurred at  load level 7 and the scuffing evaluated for surface roughness occurred at load level 12. For comparison on the uncoated C-C gearing with the Biogear S 150 oil used, scuffing evaluated for surface roughness occurred  at the 5th load level.  From the same test it is clear that the load capacity of gearings is influenced by hardness and thickness of coatings. The complete removal of the coating was preceded by gradual thinning. After its removal, the wear continued on the softer substrate, where the traces after milling filled-up with the substrate metal.
Keywords: convex-concave gearing, TiCN coating, friction coefficient, wear, adhesion, hardness, Niemann´s test, biogearfrom
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INFLUENCE OF DIE CASTING FACTORS AND OF HARDENING TEMPERATURE UPON MECHANICAL PROPERTIES OF A DIE CAST

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018108
STEFAN GASPAR, TOMAS CORANIC, JAN PASKO
Department of Design Technical Systems, Faculty of Manufacturing Technologies with a seat in Presov, Technical University of Kosice, Presov, Slovak Republic
e-mail: stefan.gaspar@tuke.sk
Abstract
In case of production of die casts utilizable especially in expansively growing automotive industry, the particular attention is devoted to a goal-oriented increase of commercial and utility properties of a product in with acceptable economical costs. In the experimental part of the submitted paper the influence of technological factors of die casting and of hardening temperature upon mechanical properties of die casts produced from the EN AC47100 alloy represented by permanent deformation, porosity and HRB hardness were performed. On the basis of performed experiments the influence of monitored factors upon final cast quality can be stemmed from.
Keywords: die cast, technological factors, hardening temperature, mechanical properties
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THE EFFECT OF RECYCLING POWDER STEEL ON POROSITY AND SURFACE ROUGHNESS OF SLM PARTS

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018110
JAN SUKAL, DAVID PALOUSEK, DANIEL KOUTNY
Brno University of Technology, Faculty of Mechanical Engineering, NETME Centre, Czech Republic
e-mail: palousek@fme.vutbr.cz
Abstract
The paper deals with the influence of the recycling of 1.2709 powder steel on porosity of the components produced by selective laser melting technology (SLM). One of the main requirements for the parts produced by SLM is to achieve good mechanical properties. The presence of pores, typical defects in the SLM produced material, is one of the causes of the mechanical properties reduction. In particular, to extend the high cycle fatigue life, it is necessary to achieve relative densities close to the full material and to minimize the pore size near the surface of the parts. One of the possible cause of pore formation and the degradation of the properties of the powder material is the standard recycling by sieving to remove the contaminants produced during the build job. Using a series of recycling tests, possible qualitative and quantitative changes of powder material and their consequences on the porosity of the manufactured parts are monitored. The paper proposes recommendations for the recycling process setup, compares the influence of the input parameters on the porosity.
Keywords: SLM, selective laser melting, powder recycling, porosity, 1.2709, 18Ni 300, martensitic steel
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INTRODUCTORY ANALYSIS OF GAS CONSUMPTION TIME SERIES IN NON-RESIDENTIAL BUILDINGS FOR PREDICTION PURPOSES USING WAVELET DECOMPOSITION

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201858
ALEXANDER HOSOVSKY, JAN PITEL, JANA MIZAKOVA, KAMIL ZIDEK
Faculty of Manufacturing Technologies with seat in Presov, Technical University in Kosice, Slovak Republic
e-mail: alexander.hosovsky@tuke.sk
Abstract
Gas consumption prediction in buildings is very important with regard to the improved decision making and better energy utilization rate. Our objective is to perform introductory analysis of gas consumption time series in three different types of non-residential buildings (elementary school, national health institute and railway station) using wavelet transform intended for prediction model identification. We use initial FFT analysis of frequency spectrum using which it was possible to identify interesting frequency components related to specific consumption patterns. In order to find out the optimal level of wavelet decomposition we use entropy-based algorithm applied to maximum level wavelet trees. It was found that gas consumption time series that optimal wavelet decomposition level in elementary school time series was 3 and other two objects was 6. Using sample autocorrelation function plots for obtained components, we were able to the components containing mainly noise which could be removed from prediction model.
Keywords: wavelet analysis, cyclic component, gas consumption, frequency spectrum, temperature
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SORPTION OF NICKEL CATIONS FROM THE WATER ENVIRONMENT ON THE CLINOPTILOLITE

M (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201859
IVETA PANDOVA
Faculty of Manufacturing Technologies with a seat in Presov, Technical University of Kosice, Slovak Republic
e-mail: iveta.pandova@tuke.sk
Abstract
One of the world's biggest problems is the lack of drinking water. The most effective methods are sought for water treatment. The latest methods include sorption on the solid layer. In order to design the arrangement of the cleaning process, it is necessary to know the adsorption isotherm and the kinetic course of sorption. The article contains laboratory experiments designed to determine the sorption parameters of nickel cations sorption on natural zeolite - clinoptilolite, which is a low cost and environmentally friendly sorption material.
Keywords: clinoptilolite, nickel, sorption, isotherm, kinetic, wastewater
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EFFECTIVE UTILIZATION OF USED DEPOSITION MODELING TECHNOLOGY

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201864
EMA NOVAKOVA-MARCINCINOVA, ANTON PANDA, LUDMILA NOVAKOVA-MARCINCINOVA
Technical University of Kosice, Department of Manufacturing Technologies, Faculty of Manufacturing Technologies with a seat in Presov, Slovak Republic
e-mail: anton.panda@tuke.sk
Abstract
This paper deals with basic knowledge and problems in area of Fused Deposition Modelling (FDM) technology operation focused on used material testing and operation optimization from economical aspects of view. It belongs to progressive methods of model creation based on geometry obtained from CAD environment with application possibilities in different industrial spheres.
Keywords: rapid prototyping, fused deposition modeling, materials for rapid prototyping
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THE TECHNIQUE FOR DETERMINING THE MOTION OF ROBOT MANIPULATOR MODEL ELEMENTS

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201865
ANTON PANDA1, EDUARD KUZNETSOV2, VOLODYMYR NAHORNYI2
1Technical University of Kosice, Department of Manufacturing Technologies, Faculty of Manufacturing Technologies with a seat in Presov, Slovak Republic
2Sumy State University, Department of Computer Science, Faculty of Electronics and Information Technologies, Sumy, Ukraine

e-mail: anton.panda@tuke.sk
Abstract
The technology of creating a motion mathematical model of an industrial robot manipulator has been proposed. Objective of the presented work is to study the motion features of industrial robot elements. The work result is a robot's computer model, which analyzes the movement elements of product moving parts.
For this purpose, a special technique of calculating the dimensional constraints of robot's elements has been developed. The technique allows to determine the permissible spatial positions of the robot elements. Taking into account possible obstacles to the movement of the robot, trajectory calculation algorithm of possible movement of robot elements has been developed.
The described technology is implemented in a robot's computer simulation using the visual design environment Autodesk Inventor. The simulation shows the movement of the robot elements, and allows to analyze the efficiency of the robot performing the specified manipulations. The program control of the simulation is performed using Autodesk Inventor API.
The developed technology is used to study the basics of robotics.
Keywords: robot, trajectory, positioning, coordinates, nodal points, movable link, software
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CONSIDER THE STRENGTH ASPECTS OF THE MATERIAL SELECTION FOR THE PRODUCTION OF PLASTIC COMPONENTS USING THE FDM METHOD

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201866
ANTON PANDA1, LUDMILA NOVAKOVA-MARCINCINOVA1, EMA NOVAKOVA-MARCINCINOVA1, JAN DUPLAK1, TADEUSZ ZABOROWSKI2
1Technical University of Kosice, Department of Manufacturing Technologies, Faculty of Manufacturing Technologies with a seat in Presov, Slovak Republic
2IBEN Gorzow Wlkp., Poznan, Poland

e-mail: anton.panda@tuke.sk
Abstract
The authors in their article are devoted to describe the samples production of sophisticated eco-material PLA -PolyLacticAcid extruded horizontally in length, produced by FDM method, Rapid Prototyping. Carried out experimental tests of mechanical properties are presented by the authors in this article. Also in this article eco-materials outputs tested are presented in patterns, measurement protocols recorded in software, the measured values in a static tensile test, recorded in tables and shown in work graphs. Based on obtained results the authors compared produced samples from two PLA eco-materials and determined which PLA – ecoplastic is stronger.
Keywords: PLA –PolyLacticAcid, 3D model, rapid prototyping, PLA eco-materials, fused deposition modelling
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THE DESIGN CRITERIA FOR BIODEGRADABLE MAGNESIUM ALLOY IMPLANTS

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201867
LEONID SUKHODUB1, ANTON PANDA2, KONSTIANTYN DYADYURA3, IVETA PANDOVA2, TIBOR KRENICKY2
1Department of Biophysics, Biochemistry, Pharmacology and Biomolecular Engineering, Medical Institute, Sumy State University, Ukraine
2Technical University of Kosice, Department of Manufacturing Technologies, Faculty of Manufacturing Technologies with a seat in Presov, Slovak Republic
3Faculty of Technical Systems and Energy Efficient Technologies, Sumy State University, Sumy, Ukraine

e-mail: anton.panda@tuke.sk
Abstract
Magnesium (Mg) and its alloys posse’s great potential for the application of biodegradable medical implants.  However, the extensive applications of Mg-based alloys are still inhibited mainly by their high degradation rates and consequent loss in mechanical integrity. Using suitable alloying elements mechanical strength and corrosion resistance of Mg-alloys can be enhanced but cytotoxicity and long term inflammatory consequences of these elements are the major concern. Further modifying the surface characteristics of Mg-alloy through various surface coating, machining, mechanical working, etc., corrosion behaviour can be manipulated. Metal matrix composites reinforced by nano-particles are very promising materials, suitable for a large number of applications. These composites consist of a metal matrix filled with nano-particles featuring physical and mechanical properties very different from those of the matrix. The nano-particles can improve the base material in terms of wear resistance, damping properties and mechanical strength. This review paper summarises the various challenges and opportunities in design and development of biodegradable Mg alloy implants.
Keywords: design criteria, magnesium alloys, magnesium composite, biocompatibility, mechanical integrity, biomaterials, orthopaedics, manufacturing processes
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PLANNING MANUFACTURING PROCESSES OF SURFACE FORMING WITHIN INDUSTRY 4.0

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201868
JAN KMEC, MONIKA KARKOVA, JAN MAJERNIK
Institute of Technology and Business in Ceske Budejovice, Faculty of Technology, Ceske Budejovice, Czech Republic
e-mail: kmec@mail.vstecb.cz
Abstract
The article explores essential prerequisites and effects for automated processes of surface forming in planning manufacturing processes within Industry 4.0. Based on authors’ practical experience and profound knowledge, they describe the adequate use of industrial robots and handlers for automated manufacturing processes. They in depth analyse methods and structures of handling operations and their application in automation of surface forming. Moreover, they give examples of handling methods and structures of operations in regard to the settings of production facility. A close attention is paid to their own structure of manufacturing process and its characteristics. Furthermore, the production system is divided into individual subsystems, and also, basic functional bonds are analysed. Eventually, production systems are divided according to the variety of their technological competences. The suggested article fits in the concept of solutions within Industry 4.0, namely in regard to its design, digitalization and data collection. 
Keywords: production process, Industry 4.0, methods and structure of operations
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METHOD OF DESCRIBING THE HEAT EXCHANGER PERFORMANCE

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201869
JAN KOLINSKY
Institute of Technology and Business in Ceske Budejovice, Czech Republic
e-mail: kolinsky@mail.vstecb.cz
Abstract
The paper deals with the method of description of heat exchanger performance. The power of the heat exchanger is usually dependent on the flow rate of the warmer and the flow rate of the colder medium and on the temperature difference of these media at the input. The power of heat exchanger is not a just a value. It is a function of these variables. Different types and designs of heat exchangers have a different power function, but these functions have some common features. The way of characterizing these functions is the subject of this work.
Keywords: heat exchanger, power performance, heat transfer, evaluation
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RELATIVE ELECTRODE WEAR AT EDM OF TOOL STEEL

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201871
LUBOSLAV STRAKA, GABRIEL DITTRICH
Department of Automotive and Manufacturing Technologies, Faculty of Manufacturing Technologies of the Technical University of Kosice with a seat in Presov, Slovak Republic
e-mail: luboslav.straka@tuke.sk
Abstract
The technology of electroerosive machining with a shaped tool electrode utilizes thermal energy when removing the material. It results from the continuous repetitive electrical discharges of high intensity between the workpiece and a tool electrode in the presence of a dielectric fluid. The gradual removal (erosion) of metal particles occurs both from the workpiece and the tool electrode, in response to the periodically repeated electric discharges. There is, however, important to emphasize that it is only desirable material removal of metal particles from the workpiece. The removal of metal particles from the tool electrode is considered to be a negative accompanying phenomenon in the case of electro-erosion machining because it causes wear. Its scope can be fairly accurately quantified using a pointer relative electrode wear. The paper describes the results of experimental research on the relative electrode wear and electrode wear rate of electrode machining tools made of Cu and G used in the electro-machining of alloyed tool steels.
Keywords: Electrical Discharge Machining (EDM), Relative Electrode Wear (REW), Material Removal Rate (MRR), Main Technological Parameters (MTP), tool steel
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OPTIMAL PREVENTIVE MAINTENANCE SCHEDULE OF SLEWING RINGS FOR DEMANDING PRODUCTION MACHINE

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201872
LUBOSLAV STRAKA, ANTON PANDA
Department of Automotive and Manufacturing Technologies, Faculty of Manufacturing Technologies of the Technical University of Kosice with a seat in Presov, Slovak Republic
e-mail: luboslav.straka@tuke.sk
Abstract
When designing any demanding production machine should be chosen minimum necessary set of technical components that are necessary to the achievement of the required functions. Moreover, the quality of fulfilling the functions is closely related to its reliability. One of the basic ways of improving the reliability of technical components of demanding production machines is increasing their reliability through preventive maintenance. By design an optimal preventive maintenance schedule of production machine can be timely and effective interventions to prevent the breakdown. This paper describes the design of optimal preventive maintenance schedule of slewing rings intended as rotating parts for demanding production CNC machine with EDM technology.
Keywords:experimental equipment, preventive maintenance, probability, slewing rings, diagnostic signal
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PARAMETRIC MODELING AS EFFICIENT WAY OF DESIGNING

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201873
ANNA SMERINGAIOVA, MAREK WITTNER
Technical university of Kosice, Faculty of Manufacturing Technologies, Presov, Slovak Republic
e-mail: anna.smeringaiova@tuke.sk
Abstract
In this article, the principle of parametric modeling as an efficient way of designing and processing technical documentation is described on the example of creating a specific parametric model.
Keywords: digital manufacturing, computer modeling, parameterization, CAD software, technical documentation
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INNOVATIVE BROAD-SPECTRUM TESTING AND MONITORING OF BELT TRANSMISSIONS

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_201874
JOZEF MASCENIK, SLAVKO PAVLENKO
Department of Design and Monitoring of Technical Systems, Faculty of Manufacturing Technologies with a seat in Presov, Technical University of Kosice, Slovak Republic
e-mail: jozef.mascenik@tuke.sk, slavko.pavlenko@tuke.sk
Abstract
The aim of this paper is to present the possibilities of testing and monitoring of belt conveyances, as well as the possibility of determining the limit states by extreme loads. The newly wrapped strap allows for extreme stresses to determine the deformation point of the belt itself. The design of the wall was based on the basic technological and constructional knowledge gained from the professional literature and practice councils. On the device, you can measure, for example, by means of mounted sensors, the actual rev counter, which is compared with the speeds set on the frequency inverters that control the electric motors. One of the wall options is to determine the slip of the belt drive by sensing the necessary parameters by means of sensors located at predetermined locations from which data is processed by a PC. By simply modifying the design of the device, it is possible to vary the different types, shapes, dimensions and conditions of aligning and setting the straps and straps. Measurement results could contribute to research into the development of new types of belt transfers.
Keywords:belt gear, tension, motor, diagnostics, stand
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POLYMER CAVITY MADE BY FREEFORMER® 3D PRINTER: AN INFLUENCE ON INJECTION MOULDED PARTS

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018125
MARTINA CESKOVA, PETR LENFELD
Technical University of Liberec, Faculty of Mechanical Engineering, Department of Engineering Technology, Liberec, Czech Republic
e-mail: martina.ceskova@tul.cz
Abstract
Injection moulding is a major technology in mass production of high quality plastic and composite parts. On the other hand, additive technology is suitable for prototyping, but produced parts do not reach as high mechanical properties as injection moulded parts do. Main advantage of additive technologies is production without expensive injection moulds. Polymer injection mould cavity inserts made by an additive technology use advantages of both mentioned technologies. Moreover, Arburg Freeformer® system presumes high quality parts made of common plastic granules.
On the contrary, polymers are thermal insulators, therefore different cooling conditions cause differences in morphology.
Removable injection mould cavity inserts from ABS and PA 10 were made using Freeformer system. The main goal was to study crystallization, morphology and thermo-mechanical properties of PP (Polypropylen) parts produced by injecting to polymer mould.
Keywords: injection moulding, prototyping, additive manufacturing, Arburg Freeformer®, polymer inserts
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FREE DIRECTIONAL ROBOTIC DEPOSITION - INFLUENCE ON OVERHANG PRINTABILITY

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018119
PETR KREJCIRIK, DAVID SKAROUPKA, DAVID PALOUSEK
Brno University of Technology, Faculty of Mechanical Engineering, NETME Centre, Czech Republic
e-mail: Petr.Krejcirik@vutbr.cz
Abstract
This article deals with a 3D printing strategy to reduce supports in the case of overhang geometry on 3D printed models realized by Fused Filament Fabrication (FFF). Experiments were performed to compare the conventional FFF process (normal orientation to the platform) with a novel strategy of 3D printing using 6-axis degrees of freedom to orient the nozzle close to the tangent direction of the 3D printed wall. The shape accuracy of the printed specimens was evaluated by an optical 3D scanner and the cross sections of the layers were observed by a digital microscope.
Keywords: 3D printing strategy, 6-axis 3D printing, robotic 3D printing, fused filament fabrication, FFF, PLA, spiral vase, KUKA PRC, Grasshopper
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FUSED DEPOSITION MODELLING VS. INJECTION MOULDING: INFLUENCE OF FIBER ORIENTATION AND LAYER THICKNESS ON THE MECHANICAL PROPERTIES

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018117
LUBOS BEHALEK1, JIRI SAFKA2, MARTIN SEIDL2, JIRI HABR1, JIRI BOBEK2
1Technical University of Liberec, Faculty of Mechanical Engineering, Liberec, Czech Republic
2Institute for Nanomaterials, Advanced Technologies and Innovation, Liberec, Czech Republic

e-mail: lubos.behalek@tul.cz
Abstract
The paper deals with comparison of tensile, flexural and impact characteristics of parts produced by injection moulding technology and Fused Deposition Modeling (FDM). The influences of various layers’ thicknesses and their orientation on the final mechanical properties of printed parts were also among the evaluated factors. ABS and PC / ABS materials were selected for the study and the analysis of the internal stresses of the moulded parts exposed to the surfactant environment (acetic acid) was also included.
Keywords: fused deposition modelling, Injection moulding, Acrylonitrile-butadiene-styrene copolymer, polymer blend, polycarbonate
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THE INFLUENCE OF HUMIDITY AND TEMPERATURE ON THE PROPERTIES OF PHOTOPOLYMER MATERIALS MADE BY POLYJET TECHNOLOGY

MM (Modern Machinery) Science Journal, December_2018
DOI: 10.17973/MMSJ.2018_12_2018122
LUBOS BEHALEK1, JIRI SAFKA2, MARTIN SEIDL2, MARTIN BORUVKA1
1Technical University of Liberec, Faculty of Mechanical Engineering, Liberec, Czech Republic
2Institute for Nanomaterials, Advanced Technologies and Innovation, Liberec, Czech Republic

e-mail: lubos.behalek@tul.cz
Abstract
The paper is focused on the study of environmental changes and their impact on selected mechanical properties of parts made of photopolymer materials used by the PolyJet technology. Discussion deals with changes in material properties of parts exposed to increased temperature and humidity. Different layer orientations during 3D printing of parts was another evaluating aspect that influenced the final mechanical properties. All analysed materials were graded according to the hardness in order to observe changes in mechanical properties of the widest possible range of materials that can be processed by this technology.
Keywords: PolyJet, photopolymers, 3D Print, mechanical properties
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