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EN
In this paper some rules of mesh-free/meshless modelling and numerical simulations of fundamental physical phenomena associated with the machining process, including mechanisms of plastic deformation, chip formation and interfacial friction are overviewed. Some representative examples of the mesh-free modelling application to material removal processes at different scales, i.e.: machining processes, water jet-assisted processes, additive machining processes and simulation of micromachining processes using predominantly SPH (smoothed particle hydrodynamics) method are given.
PL
W artykule omówiono zasady bezsiatkowego modelowania i symulacji numerycznej podstawowych zjawisk fizycznych towarzyszących procesom obróbki, w tym mechanizmów odkształcania materiału, tworzenia wióra i tarcia. Podano przykłady zastosowania bezsiatkowego modelowania procesów obróbki ubytkowej, m.in.: obróbki skrawaniem, wysokociśnieniową strugą wody (WJM i AWJM) oraz obróbki i symulacji mikroobróbki z użyciem metody SPH (hydrodynamiki wygładzonych cząstek).
EN
In this paper some rules of a multiscale modelling and numerical simulations of fundamental physical phenomena associated with the machining process, including mechanisms of plastic deformation, chip formation and interfacial friction are overviewed. Some representative examples of the modelling application to multiphase and composite materials, determination of constants in the material constitutive equations and simulation of nano- and micromachining processes using MD-FEM and SPH-FEM hybrid methods are given.
PL
W artykule omówiono zasady wieloskalowego modelowania i symulacji numerycznej podstawowych zjawisk fizycznych towarzyszących procesowi skrawania, w tym mechanizmów odkształcania materiału, tworzenia wióra i tarcia. Podano przykłady zastosowania modelowania materiałów wielofazowych i kompozytowych, wyznaczania stałych materiałowych w równaniu konstytutywnym oraz symulacji mikro- i nanoobróbki z użyciem hybrydowej metody MD-FEM i SPH-FEM.
EN
Rapid evolution in sensing, data analysis, and industrial internet of things technologies had enabled the manufacturing of advanced smart tooling. This has been fused with effective digital inter-connectivity and integrated process control intelligence to form the industry I4.0 platform. This keynote paper presents the recent advances in smart tooling and intelligent control techniques for machining processes. Self-powered wireless sensing nodes have been utilized for non-intrusive measurement of process-born phenomena near the cutting zone, as well as tool wear and tool failure, to increase confidence in the process and tool condition monitoring accuracy. Cyber-physical adaptive control approaches have been developed to optimize the cycle time and cost while eliminating machined part defects. Novel artificial intelligence AI-based signal processing and modeling approaches were developed to guarantee the generalization and practicality of these systems. The paper concludes with the outlook for future work needed for seamless implementation of these developments in industry.
EN
In this paper, the structure and operational functions of a measurement system, which was installed on a 3-axis CNC lathe for monitoring and optimization of the cutting process are presented. In general, the system records signals of the components of the resultant cutting force, acceleration signals (cutting vibrations) and EFM force signals generated for various machining conditions employed. As a result, the total power consumed was determined. The generated data were archived in the expert system which supports the optimization of the cutting process in terms of various optimization criteria including power/energy consumption.
PL
W artykule przedstawiono budowę i funkcje eksploatacyjne układu pomiarowego, który został zainstalowany na 3-osiowej tokarce CNC w celu monitorowania i optymalizacji procesu skrawania. System rejestruje sygnały składowych wypadkowej siły skrawania, sygnały przyspieszenia (drgania skrawania) oraz sygnały siły EFM generowane dla różnych zastosowanych warunków obróbki. W rezultacie określono całkowitą pobieraną moc. Wygenerowane dane zostały zarchiwizowane w systemie ekspertowym, który wspiera optymalizację procesu cięcia pod kątem różnych kryteriów optymalizacji, w tym poboru mocy / energii.
EN
A special group of hybrid assisted processes termed media-assisted processes which apply liquid media with special additives in the form of nanoparticles supplied to the cutting zone is overviewed. Special attention is paid to minimum quantity lubrication (MQL) technique with the use of nanofluids. In this review paper some important thermal and tribological effects resulting from the applications of various nanoparticles are outlined and compared. The MQL-nano cutting fluid mechanisms (rolling and ploughing) are described. In particular, some important quantitative effects concerning thermal and tribological behaviour of the cutting process as well as surface quality are presented.
6
Content available remote Design and fabrication of Abrasive Jet Machine (AJM)
EN
Abrasive Jet Machining (AJM) is the process of material removal from a work piece by the application of a high-speed stream of abrasive particles carried in a gas or air medium from a nozzle. The material removal process is mainly by erosion. The AJM will chiefly be used to cut shapes in hard and brittle materials like glass, ceramics etc. the machine will be automated to have 3 axes travel. The different components of AJM are Compressor, Vibrator, dehumidifier, Pressure Regulator, and Dust filter, Nozzle, Pressure gauge etc. The different components are selected after appropriate design calculations. In paper contains the Abrasive Jet Machine design and fabrication by using available hardware and software etc. taking into consideration of commercially available components. Care has been taken to use less fabricated components rather than directly procuring them, because, the lack of accuracy in fabricated components would lead to a diminished performance of the machine.
EN
The article discusses the importance of energy consumption for the modern machine tool. The research was carried out to show the influence of various cutting factors and parameters on the power consumption values of the machine tool. A special algorithm was developed to determine the actual energy consumption of the machine tool during the cutting process. The results of the study were compared with the algorithms of tool companies to determine the machine’s power demand. The possibilities of using research conclusions to develop a more accurate method for assessing the energy demand of a machine tool in the cutting process were indicated.
EN
The paper presents the information about the energy consumption in the machining process. It has been shown how looks the power consumption of the lathe, what factors impact on it. It was discussed the negative impact of reactive power in the electricity grid and the possibilities of its compensation. The analysis and comparison of the power consumption was made for a conventional and CNC lathe.
9
Content available remote Efektywność energetyczna procesu obróbki skrawaniem na przykładzie toczenia
PL
Efektywność energetyczna procesów produkcyjnych stała się w ostatnich latach jednym z priorytetowych działań organizacji. W referacie przedstawione zostały wyniki badań przeprowadzonych na tokarce w Instytucie Technologii Mechanicznej. Prezentowane wyniki przedstawiają rzeczywiste przebiegi procesu obróbki elementów produkowanych seryjnie.
EN
The energy efficiency of production processes has become in recent years one of the priority activities of the organization. The paper presents the results of studies conducted on a lathe at the Institute of Mechanical Technology. The results presented represent the actual waveforms process of machining of parts manufactured in series.
10
Content available remote Wskaźniki zdolności jakościowej w procesach obróbki skrawaniem
PL
W artykule zdefiniowane zostały wskaźniki zdolności jakościowej procesów obróbki skrawaniem o wartości docelowej nie pokrywającej się ze środkiem przedziału tolerancji. Przypadki takie rzadziej występują w praktyce produkcyjnej, a ich analiza na bazie klasycznych wskaźników może prowadzić do bardzo poważnych błędów. Podane zostały przykłady zastosowania takich wskaźników, ich interpretacja oraz szacowanie przedziałów ufności. Publikacja dedykowana jest przede wszystkim gronu specjalistów zajmujących się dokładnością procesów obróbki skrawaniem, ale może być wykorzystana również w innych metodach obróbki metali.
PL
W artykule opisano prace związane z wyznaczeniem wielkości współczynnika tarcia w rolkach napędowych tokarki podtorowej UGE 150N. Znajomość współczynnika tarcia umożliwia zmiany parametrów docisku rolek w celu uzyskania większych wydajności obróbki.
EN
The paper presents a study devoted to the determination of volume of the friction coefficient at driving rolls of an under-floor wheel lathe - UGE 150N model. The identification of the friction coefficient allows amending the parameters responsible for clamp of the rolls so as to increase the efficiency of the machining process.
EN
Commonly applied theories of self-excited vibrations in machine tools are prevailingly based on frequency domain analysis of linear models and are devoted in most cases only to evaluation of stability limits of strictly linear systems. In this way, the behaviour of more stable or more unstable systems cannot be studied and analyzed. Certain important nonlinear effects cannot be studied as well for limitations connected with classical representation of systems only in the frequency domain. Evaluation of stability by analysis of nonlinear systems in time domain has not been applied until now. The paper shows a new approach based on interpretation of the self-excited vibration systems as nonlinear servo-systems. With this approach, linear and nonlinear systems of any degree of stability can be studied by combination of frequency and time-domain methods. This can considerably contribute to better understanding of complex phenomena in various regimes and special situations.
PL
W artykule opisano zastosowanie programu Unigraphics NX4 do tworzenia programów NC. Przedstawiono proces modelowania obrabiarki, proces tworzenia postprocesora i proces generowania ścieżek narzędzia do obróbki ubytkowej części maszyn Zaprezentowano praktyczny przykład obróbki elementu.
EN
This paper presents the application of the Unigraphics NX4 system for creating NC programs. It has been presented the process of machine tool modeling, post-processor creating and a tool-paths generating for machining machine parts. The practical example of an element machining is also included.
15
Content available remote Symulacja procesów obróbkowych w środowisku naturalnym
PL
Przedstawiono proces tworzenia wirtualnego środowiska wytwarzania w systemie NCSIMUL. Opisano metodykę postępowania prowadzącą do budowy wirtualnej obrabiarki, dla której przeprowadzono symulację obróbki wielogniazdowej formy obrotowej. Dokonanie optymalizacji tego procesu i analiz wymiarowych produktu w środowisku wirtualnym umożliwiło pozytywne wdrożenie jego obróbki na maszynie rzeczywistej.
16
Content available remote Badania symulacyjne procesów obróbkowych w środowisku wirtualnym
PL
Przedstawiono proces tworzenia wirtualnego środowiska wytwarzania w systemie NCSIMUL. Opisano metodykę postępowania prowadzącą do budowy wirtualnej obrabiarki, dla której przeprowadzono symulację obróbki wielogniazdowej formy obrotowej. Dokonanie optymalizacji tego procesu i analiz wymiarowych produktu w środowisku wirtualnym umożliwiło pozytywne wdrożenie jego obróbki na maszynie rzeczywistej.
EN
The paper introduces a process of creating a virtual environment of production in the NCSIMUL system. Described is a methodology leading to the creation of a virtual CVC machine tool, on which machining of a rotary, multi-cavity mould was simulated. Optimization of such process and dimensional analysis of the product in the virtual environment allowed for successful implementing the machining process on a real machine tool.
17
Content available remote Optimal tools setting of automatic multispindle lathes with CNC
EN
For execution of turning operations in requirements multi-product manufacture usage of multi-spindle turning automatic machines number controlled is expedient. The procedure of optimisation the technological solutions surveyed at definition structures of cluster adjustments turning automatic machines. The optimality of the factor multi-tools is considered from positions of reaching of an accuracy of job surfaces.
18
Content available remote Forming of the flanks of hobs cutting edges using a disk-type grinding wheel
EN
The element determining the accuracy of machining a gear wheel is the cuttiug edge of the hob. A cutting edge is a result of the intersection of the surface of attack by the hob cutting edge flank. The flanks of hobs can be formed by using grinding wheels, disk-type grinding wheels and finger-type grinding wheels. For small module hobs this is the disk-type grinding wheel of a rectilinear axial profile. However to increase the accuracy of the cutting edge we propose application of the disk-type grinding wheel of a circular axial profile, which makes it possible to receive the hobs of the AAA class accuracy. The proposed changes have been verified trough the computer program "Analysis of hob profiles" developed by the authors of this study and in the series of experimental tools.
19
Content available remote Dynamically stable milling tools with integrated cut splitting
EN
The principle of the cut-splitting can guarantee an effective cutting even under the difficult conditions of stability. To divide the chip in two or more pieces, the geometric relations of the cutting area of every chip are changed. This change is caused by the cutting forces and therefore by the dynamic behaviors of the whole process. The advancement of the principle of cut-splitting obviously increases the dynamic behavior. In particular, under unstable conditions of machine processing in practice, these new milling tools outclass the ordinary milling heads because of their fewer vibrations and noise.
20
Content available remote Dry cutting gear hobbing in modul range m≥4 mm with HSS tools
EN
In line with the project the high work potential of dry cutting and minimum quantity lubrication (MQL) with coated HSS-gear hobs will be shown in order to realize an economical and reliable method for gear hobbing of toothed systems with bigger modules, which works completely without or nearly without cooling fluids respectively. For the investigations was used common material for gears in a module range from 4 mm to 7 mm and progressive cutting values similar to industrial applications. It was demonstrated that industrial produced gear hobs from powder metallurgical HSS with TiAlN coatings by using methods of dry cutting and MQL can resist the occurring process charges due to the bigger modules and gear width. In comparison to the state of technical knowledge which is wet cutting was ascertained an enormous increase of tool life by using this method of dry cutting and MQL.
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