ANALYSIS OF FINISHING VERY PRECISE HOLES BY THE REAMING HEAD MT3

MM (Modern Machinery) Science Journal, October_2018
DOI : 10.17973/MMSJ.2018_10_2017101
JOSEF SEDLAK1, KAREL KOURIL1, JOSEF CHLADIL1, ALES JAROS1, STANISLAV FIALA2, ZDENEK FIALA3
1Brno, University of Technology, Faculty of Mechanical Engineering, Institute of Manufacturing Technology, Brno, Czech Republic
2Brno, FINAL Tools Inc., Brno, Czech Republic
3Kurim, Intemac Solutions Ltd., Kurim, Czech Republic

e-mail: sedlak@fme.vutbr.cz
Abstract
The paper deals with the analysis of the finishing of very precise holes by the applied MT3 reaming head from FINAL Tools Inc. In the case of a narrow range of customers with particularly high demands on the quality of the holes is currently appearing effort to elaborate a detailed evaluation of surface quality through evaluation of surface integrity.
These facts led to the design of an experimental part in the form of an analysis of the surface integrity of the test holes machined by the reaming head MT3 during its durability. Surface integrity was assessed from the point of view of circularity, cylindricality, surface roughness, surface defects controlled by electron microscopy, microhardness and metallographic analysis of lateral extrusion. For the completeness of the measured parameters, the dimension of the reamed test holes was also measured.
Keywords: MT3, reaming heads, finishing operations, precise holes, surface integrity
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DEVELOPMENT OF REVERSE ENGINEERING METHODODOLGY FOR THE PRODUCTION OF MACHINE PART

MM (Modern Machinery) Science Journal, October_2018
DOI : 10.17973/MMSJ.2018_10_2017116
ARAVINDPRASAD SRIKANTHAN, RADOMIR MENDRICKY, PETR KELLER
Technical University of Liberec , Department of Manufacturing Systems and Automation, Liberec, Czech Republic
e-mail: aravind.prasad19@gmail.com
Abstract
Engineering design is the preliminary and significant technique for manufacturing the machine parts. Conventional design methodology is the process by which desired models are transformed into real parts. Using reverse engineering concept, the real parts are transformed into models. This article deals with developing a methodology for reverse engineering of machine parts with parametric surfaces. Real part was digitized with 3D scanner and obtained digital data was processed with Geomagic DESIGN X to create 3D solid model. Numerical Codes (NC) are generated in Edgecam software by utilizing the solid model and the new part was manufactured in MAZAK INTEGREX a Computer Numerical Control (CNC) machine. Inspection procedure was performed before and after manufacturing of the new part using GOM Inspect 3D.
Keywords: reverse engineering, atos ii 400, polygonal mesh, geomagic design x, solid model, edgecam, gom inspect
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EVALUATION OF RESIDUAL STRESS IN CONDITIONS OF IRREGULAR INTERRUPTED CUT

MM (Modern Machinery) Science Journal, October_2018
DOI : 10.17973/MMSJ.2018_10_201804
ROBERT CEP1, SARKA MALOTOVA1, KAREL KOURIL2, LENKA CEPOVA1, LADISLAV KYNCL1, MICHAL SAJGALIK3, TATIANA CZANOVA3
1Technical University of Ostrava, Faculty of Mechanical Engineering, Ostrava, Czech Republic
2Brno University of Technology, Faculty of Mechanical Engineering, Brno, Czech Republic
3University of Zilina, Faculty of Mechanical Engineering, Zilina, Slovak Republic

e-mail: robert.cep@vsb.cz
Abstract
Residual stress occurs in many machined components and parts and they cause the corrosion or destruction of components. The paper deals with evaluating residual stresses during an irregular interrupted cut with the use a ceramic cutting tool. Tests were performed on the conventional lathe with using a simulator of interrupted cut called “slats test”. The regular or irregular interrupted cutting process was simulated with a different number of clamped slats in the simulator. Machined slats were made from two kind of material, steel C45 and 14MoV6-3. For evaluation of residual stress there was selected the non-destructive method based on the principle of X-ray diffraction. The results were measured by the device Proto iXRD Manufacturing. The experiment was done in cooperation with the University of Zilina in Zilina, Slovakia.
Keywords: interrupted cut, ceramic cutting tool, residual stress, x-ray diffraction, machining
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CALCULATION OF CARBON DIFFUSION FORCEMENTATION OF GEAR WHEELS

MM (Modern Machinery) Science Journal, October_2018
DOI: 10.17973/MMSJ.2018_10_201826
JIRI MACHUTA, IVA NOVA, PAVEL SEVCIK
Technical University of Liberec, Department of Engineering Technology, Liberec, Czech Republic
e-mail: jiri.machuta@tul.cz
Abstract
The paper deals with the determination of the precise calculation of carbon diffusion and carbon prediction in the production of gear wheels cementation from steel by Czech standard (steel CSN 14220, or ASTMA 506). In the research part of the paper, considerable attention is paid to the determination of the necessary data for calculating the cementation, especially the mass- the carbon-binding coefficients ßC and the determination of the value of the carbon diffusion coefficient DC. A diffusion analysis was performed with respect to its kinetics. At the same time, the essence of diffusion in metals is described, and attention is paid to the cementation of the selected steel, i.e the diffusion conditions of its cementation. According to industrial experience, three cementation times for steel gears were chosen. The main attention was paid to calculating the diffusion and distribution of carbon in the wheel teeths under different conditions of cementation. In addition to the definite input variables of the diffusion process, the mass-carbon ß determined on the basis of WYSS recommendations [Wyss 1978]. This factor affects the thickness of the diffusion boundary layer at the interface of the metal atmosphere resulting from carbon transfer and defines the amount of carbon atoms that receives the surface of the steel from the carbonaceous atmosphere. Also, the significant diffusion coefficient D was determined based on the findings [Pisek 1974] and [Brandes 1992]. Based on the diffusion production parameters included in the calculation, experimental cementation of gears was performed under different conditions. The layer of overfilled carbon in wheel teeth, their measurement and statistical evaluation were monitored. The basis was to achieve 0.4 wt. % C in three types of diffusion layers (0.6 mm, 0.8 mm and 1.0 mm). Gears after cementation were hardened and tempered. On these technologically processed wheels, microhardness was monitored, the CHD 550 value and the microstructure at various points of the teeth of the wheels were determined.
Keywords: cementation, steel, carbon, diffusion, gear, wheels
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PRODUCTION OF ROLLED PROFILE AND ITS VERIFICATION BY USING NUMERICAL SIMULATION

MM (Modern Machinery) Science Journal, October_2018
DOI : 10.17973/MMSJ.2018_10_201831
JAN RIHACEK1, LUKAS SIGMUND1,2
1Brno University of Technology, Faculty of Mechanical Engineering, Institute of Manufacturing Technology, Department of Metal Forming, Brno, Czech Republic
2VUHZ, a. s., Dobra, Czech Republic

e-mail: rihacek.j@fme.vutbr.cz
Abstract
The paper deals with a manufacturing technology of hot-rolled sections. A calibration system proposal of the solved section is described and its accuracy is subsequently verified by numerical simulation using Simufact Forming software. In this case, S355J2 steel is used as a material for a trial production of the rolled profile. Finally, according to the verified design, the trial rolling of the section is carried out. Therefore, a comparison between actual rolled section shapes of individual rolling passes and simulation results is performed. This makes it possible to assess the accuracy of the simulation and thus the suitability for use in the development of other rolled sections.
Keywords: hot rolling, profile, S355J2 steel, fem, numerical simulation, simufact forming
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EXPERIMENTAL EVALUATION OF SYSTEM EFFICIENCY FOR A HYDRAULIC HYBRID ARCHITECTURE OF EXCAVATORS

MM (Modern Machinery) Science Journal, October_2018
DOI : 10.17973/MMSJ.2018_10_201836
SEIJI HIJIKATA, PHILIPP WEISHAAR, ROLAND LEIFELD KATHARINA SCHMITZ
RWTH Aachen University, Institute for Fluid Power Drives and System (ifas), Aachen, Germany

e-mail: Seiji.Hijikata@ifas.rwth-aachen.de
Abstract
Development and research for an Open Center System (OC-System), which is typically used for excavators, has been conducted from the perspective of hydraulic efficiency. However, total system efficiency including the internal combustion engine (ICE) has not been considered thoroughly. On the other hand, a Constant Pressure System (CP-System) enabling the engine to be driven optimally is developed but is not accepted in the industry due to the complexity of the required components. Thus in this research, a hybrid system combining an OC-System with a CP-System is proposed enhancing the total system efficiency. The new system consists of an open center valve, an accumulator and a minimum of required components for the CP-System. In order to confirm the system efficiency, experiments are conducted with a test rig based on a 7t excavator. The test results lead to an estimated reduction in fuel consumption of 16 % compared to the conventional OC-System.
Keywords: hydraulic hybrid, open center, constant pressure, system efficiency, mobile hydraulics, excavators
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LOAD CYCLE INVESTIGATION OF AXIAL PISTON UNITS INTEGRATED INTO A FORWARDER

MM (Modern Machinery) Science Journal, October_2018
DOI: 10.17973/MMSJ.2018_10_201837
IVAN BAUS1, ROBERT RAHMFELD1, ANDREAS SCHUMACHER1, HENRIK PEDERSEN2
1Danfoss Power Solutions, Neumünster, Germany
2Aalborg University, Department of Energy Technology, Denmark

e-mail: ivb@et.aau.dk
Abstract
The consideration of the drivetrains behavior under real operating conditions is becoming increasingly important. While in the past decades it was good enough to have a rough knowledge about the operation conditions in field, a more accurate and detailed picture of the duty cycles is required today. Caused by specific and complex operation conditions the load deviation between different applications is significant. In many cases like e.g. lifetime calculation, a precise knowledge of field conditions leads to the more accurate calculated or simulated results. This paper covers the duty cycles investigation of a forwarder application in field including the measurement concept and implementation. Especially, the analysis of the load conditions, clustering algorithm and lifetime calculation is included. The load spectrum generation is consequently done based on comprehensive load cycle determination. The Aim of this work is to verify the calculation accuracy of the load spectrum by using the clustered and raw data. The outcome of the investigation gives an indicator for the load degree of the drivetrain. Here the developed method creates a new and fast possibility of data analysis and is applicable to most drivetrain applications. Furthermore, the collected data is used as reference for future investigation of the forwarder evolution.
Keywords: axial piston unit, load cycles, clustering algorithm, measurement system, drivetrain, load assessment
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THEORETICAL AND EXPERIMENTAL ANALYSIS OF THE BEARING JOURNAL MOTION DUE TO FLUID FORCE CAUSED BY THE OIL FILM

MM (Modern Machinery) Science Journal, October_2018
DOI: 10.17973/MMSJ.2018_10_201840
JIRI TUMA1, MILADA KOZUBKOVA2, MIROSLAV PAWLENKA1, MIROSLAV MAHDAL1, JIRI SIMEK3
1Technical University of Ostrava, Faculty of Mech. Engineering Department of Control Systems and Instrumentation, Ostrava, Czech Republic
2Technical University of Ostrava, Faculty of Mech. Engineering, Department of Hydraulics, Ostrava, Czech Republic
3TECHLAB Ltd., Prague, Czech Republic

e-mail : jiri.tuma@vsb.cz
Abstract
The paper relates to the fluid force acting on the journal of the slide bearings and its movement at stable lubrication. These forces can be calculated using the Reynolds equation. The analysis is based on the solution of the simplified equation and the experimental verification with the use of the test rig. The assumptions are verified by the numerical solution of the Reynolds equation by the FVM method.
Keywords: journal bearings, reynolds equation, fluid forces, muszynska model
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COMPARISON OF THE ENERGY CONSUMPTION OF THE HYDRAULIC CONTROL SYSTEM OF THE  UDS 114

MM (Modern Machinery) Science Journal, October_2018
DOI: 10.17973/MMSJ.2018_10_201842
MICHAL JUZA, PETR HERMANEK
Czech University of Life Sciences Prague, Faculty of Engineering, Department of Agricultural Machines, Prague, Czech Republic
e-mail: michal-juza@centrum.cz
Abstract
This article deals with the comparison of the energy consumption of the hydraulic control system of the working mechanisms of the telescopic excavator UDS 114. There is described the hydraulic system of the excavator. In order to compare the individual losses in the hydraulic circuits for controlling the working mechanisms, the hydraulic oil flow rates through the OTC H50 meter were measured. Firstly, for the machine before a repair and subsequently after the repair. For each hydraulic circuit, the hydraulic oil flow rates between the pump and the distributor and then between the distributor and the appliance were measured at first.  The overall power losses of the hydraulic circuit is then determined from particular calculations. From these calculated power losses of individual hydraulic circuits, the efficiency of individual hydraulic circuits in the state of the machine before and after repair was evaluated.
Keywords: loss, hydraulic, flow rate, pressure
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MEASURING OF ROTARY AIR MOTORS CHARACTERISTICS

MM (Modern Machinery) Science Journal, October_2018
DOI: 10.17973/MMSJ.2018_10_201844
LUKAS DVORAK, KAMIL FOJTASEK
Technical University of Ostrava, Faculty of Mechanical Engineering, Department of Hydromechanics and Hydraulic Equipment, Ostrava, Czech Republic
e-mail: lukas.dvorak@vsb.cz
Abstract
In the article the construction of an experimental device for measuring the characteristics of small rotary air motors        is described. Further a measurement methodology and measured data processing is explained. At the end of the article using of the measured characteristics for mathematical modelling is presented.
Keywords: air motor, measurement, mathematical model
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TENSILE RESISTANCE OF THE COMBINE HARVESTER WITH TRACKED CONCEPT OF CHASSIS

MM (Modern Machinery) Science Journal, October_2018
DOI : 10.17973/MMSJ.2018_10_201848
LUKAS BENES, PETR HERMANEK
Czech University of Life Sciences Prague, Faculty of Engineering, Department of Agricultural Machines, Prague, Czech Republic
e-mail: benesl@tf.czu.cz
Abstract
For measuring was used the combine harvester John Deere S685i with track units. For reading of tension force there was used specially developed measurement tool - a pull dynamometer. It is constructed as a towing drawbar which was connected between rear hitch of combine harvester and three-point hitch of pulling tractor. It means that measuring set moved in reverse mode. Measuring was running on the same path as in case of wheeled combine harvester: asphalt surface, maximum slope 0.2°, length of path 120 meters. Speed of towing simulated usual working speed during harvest. There were measured three variants of speed it were 4, 6 and 8 km.h-1 and each variant was repeated three times. After collecting of data for each speed variant consequently there were calculated different tensile resistance which we can observe. Tensile resistance correspond with load of drivetrain, load of engine and it directly affects fuel consumption.
Keywords: combine harvester, tensile resistance, tracks, travel gear
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OPTIMIZATION METHOD FOR DESIGNING OF HYDRAULIC ELEMENTS

MM (Modern Machinery) Science Journal, October_2018
DOI : 10.17973/MMSJ.2018_10_201849
MILADA KOZUBKOVA, JANA JABLONSKA, MARIAN BOJKO, PATRIK MARCALIK
Technical University of Ostrava, Departament of Hydromechanics and Hydraulic Equipment, Ostrava, Czech Republic
e-mail: milada.kozubkova@vsb.cz
Abstract
Two methods are generally possible to design and optimize hydraulic components and devices.
The classic method is the experimental method. In the hydraulic laboratories, various models of components and devices are examined to understand their basic properties, to verify proposed assumptions, or to alter derived theoretical equations to equations that approximate reality, etc. In some cases, which are very difficult to solve theoretically, or even yet unsolvable, you can only get the values you need using an experiment. However, not all phenomena can be described through models.
Mathematical-physical modeling is a method by which Mathematical models based on the application of physical laws and phenomena can achieve the necessary results. These mathematical models consist of the definition of equations describing the given processes, which must be solved by means of numerical methods. Fluent, CFX Computerized software is used to solve the problem. Simulation can be performed within these softwares, which allows to evaluate different variables in a short period of time, to change the design of the element to suit the application, etc. However, it is a prerequisite to check the retained results by the experimental method.
The method of optimizing the parameters and shapes of products and equipment is already an integral part of the design process. This achieve product shape improvement without having to produce A number of Prototypes, you can create a variety of variants and perform simulations for different conditions. At present, the mathematical optimization method is based on the principle of adjunction, which is part of the ANSYS Fluent solution, which means saving time and finance while achieving qualitative improvement.
The article focuses on the theoretical and practical possibilities of using this method in the field of hydraulic elements.
Keywords: optimization, goal function, cfd, adjoint solver
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EFFECT OF TEMPERATURE, FLOW RATE AND CONTAMINATION ON HYDRAULIC FILTRATION

MM (Modern Machinery) Science Journal, October_2018
DOI: 10.17973/MMSJ.2018_10_201852
J.M.R. GORLE, V-M HEISKANEN, S. NISSI, M. MAJAS
Hydraulic and Fuel Filtration Division, Parker Hannifin, Urjala, Finland
e-mail: gorle.jmr@gmail.com
Abstract
The performance of a mechanical filter is an implicit function of many variables pertinent to fluid condition, flow variables, filter element condition and operational parameters. This paper presents the details and results of a parametric study that examined the effect of oil temperature, contamination level and flow rate on the performance of a hydraulic filter through laboratory experiments. A 5 µm rated commercial filter with glass fiber made element that had an effective surface area of 0.154 m2 through 57 pleats was used to filter VG32 hydraulic oil. The filtrate was supplied with the contaminant of ISO medium test dust at four gravimetric levels - 2, 5, 8 and 10 mg/L of oil. The tests were conducted at the flow rates of 40 and 120 L/min for different oil viscosities, corresponding to the temperatures of 30, 40, 50 and 60o C. As the temperature increases, the oil viscosity decreases due to weakened cohesive forces, which leads to increased filtration rates and hence more time to build the pressure, upstream of the element. On the other hand, the pressure on upstream of filter bed builds up at higher rate when the filtrate has higher level of contamination loading. An extensive investigation on the effect of flow variables and oil condition parameters on the pressure drop across the element would therefore give a better knowledge about filter element lifetime.
Keywords: hydraulic filtration, temperature, flow rate, gravimetric level, pressure drop
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EXPERIMENTAL TESTING OF POWER ASSISTED STEERING

MM (Modern Machinery) Science Journal, October_2018
DOI : 10.17973/MMSJ.2018_10_201853
PETR NOSKIEVIC, MARTIN BREZINA
Technical University of Ostrava, Faculty of Mechanical Engineering, Department of Automatic Control and Instrumentation, Ostrava, Czech Republic
e-mail:  petr.noskievic@vsb.cz
Abstract
The paper is focused on the description and creating of the simulation model of the power assisted steering and testing of the functionality and efficiency on the laboratory test rig. The mathematical model is describing the structure of the system and is created from the mathematical models of the subsystems, which compute the dynamic behaviour of the steering wheel, pinion, rotating control valve and of the hydraulic cylinder. The simulation model was realized in the simulation programme MATLAB-Simulink® and was used for the simulation of the testing experiment. The measurements were done on the laboratory test rig, which is controlled by the computer and operated by the swivel pneumatic drive instead of the driver hand. It allows better repeatability of the experiment. The experiments were focused on the evaluation of the efficiency of the hydraulic power assisted steering system.
Keywords: power assisted steering, hydraulic drive, mathematical model, simulation
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DESIGNOF SIMULATION-EMULATION LOGISTICS SYSTEM

MM (Modern Machinery) Science Journal, October_2018
DOI : 10.17973/MMSJ.2018_10_201878
MILAN GREGOR , ROBERT HODON, VLADIMIRA BINASOVA, LUBOSLAV DULINA, MARTIN GASO                
University of Zilina, Faculty of Mechanical Engineering, Department of Industrial Engineering, Zilina, Slovak Republic
e-mail: vladimira.binasova@fstroj.uniza.sk
Abstract
In modern industrial practice, innovative solutions for the improvement of processes or whole production or logistical systems are continually proposed. There are many options offered, but the problem arises in verifying the correctness of decisions and their impact on the functioning of logistic processes and the entire production system after the implementation of the changes. Forecasting or experimentation can be carried out, but there are also more appropriate verification methods because changes can have a significant economic impact on the enterprise. This paper deals with the simulation and emulation of logistics processes, because the simulation is an effective tool for detecting potential in production and logistics, as well as forthe elimination of shortcomings in the design phase of a particular solution in an enterprise. Another proposed intelligent solution is emulation, as part of the decision-making and management support systems. The resulting design of the simulation-emulation logistic system allows a significant shortening period of commissioning. The emulation of production systems is also intended for the rapid verification of the impact of guiding principles in advanced production systems for discrete production. These systems are called adaptive logistical systems that use the adaptability of new types of technologies based on reconfigurable production systems.
Keywords: simulation, emulation, logistics system, innovative system
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