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1

A review on machinability in the milling processes

Demirpolat Havva, Kuntoğlu Mustafa, Binali Rüstem

Sustainable Production, Instrumentation and Engineering Sciences

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2023

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vol. 1, nr 1

27--36

EN

This review paper focuses on the up-to-date machinability characteristics of milling processes such as cutting forces, surface roughness and tool wear and their impacts on the cutting mechanism. The methodology pur-sued in this paper is to analyze the previous research articles published between 2019–2022 classifying them into the subcategoriesthat usemill-ing operation as manufacturing strategy. As known, milling is one of the most used machining processes in industry and often applied for academic studiesforawide range of materials. Therefore, used sensor systems, main aim and the preferred methodology were summarized in the context of this paper. Seemingly, a great number of machinability papers have been published recently which focuses on the several types of engineering ma-terials and utilized various types of sensor system to improve the surface roughness and tool life. In addition, the investigation showed that optimi-zation approaches have been applied broadly to detect the best machining conditions. Also, it was observed that several modeling approaches such as finite element analysis is a good alternative to analyze the process.

2

Improving the efficiency of the milling tool by reducing the temperature in the milling zone depending on the main mode parameters

Mustafayev Amir G., Ismayilov Mahmud, Salimli Mirkamran M., Nasirov Chingiz M.

Nafta-Gaz

|

2023

|

R. 79, nr 12

764--775

EN

Maintenance of equipment and tools used in the overhaul of oil and gas wells depends on the reliability and durability of the tool. The recovery process of damaged wells can be accelerated by choosing the right repair equipment and following the rules and regulations in force. Cutting equipment and tools operating under high pressure and load are deformed, in the cutting zone – dispersion, i.e., a tense situation is created, and as a result of corrosion in the tribonodes, high temperatures, such as 1000–1200°C, are observed. The stress-strain state created in the shear-disintegration zone causes the formation of microcracks in the working zone of the tool, which will grow over a certain period of time. Thus, the cutting elements wear out quickly, in some cases break and quickly fail. In this case, the structural composition of the cutting elements changes, and the structural lattice in metals is destroyed, resulting in riveting. To maintain the equipment and tools used in repairs in working order, one of the important conditions is their special care and adjustment of the mode parameters. This article discusses the increase in the efficiency of the milling tool with the use of cooling agents in the process of milling various metal objects left during accidents in the wellbore. To do this, experimental data were processed, based on regression analysis, mathematical formulas were obtained that describe the temperature process depending on various regime parameters of the grinding process, and their graphical dependences were plotted. A transition from linear regression to non-linear regression has been made. The results obtained make it possible to predict the classification and design schemes of borehole cutters and the choice of composite materials for reinforcing the cutting part.

PL

Konserwacja sprzętu i narzędzi stosowanych w naprawach odwiertów ropnych i gazowych zależy od niezawodności i trwałości narzędzia. Proces odzyskiwania uszkodzonych odwiertów może być przyspieszony poprzez wybór właściwego sprzętu naprawczego oraz przestrzeganie obowiązujących zasad i przepisów. Sprzęt tnący i narzędzia pracujące pod wysokim ciśnieniem i obciążeniem ulegają odkształceniu, w strefie cięcia powstaje dyspersja, tj. warunki naprężenia, a w efekcie korozji w węzłach tribologicznych pojawiają się wysokie temperatury rzędu 1000–1200°C. Stan naprężeń-odkształceń wytworzony w strefie ścinania-dezintegracji powoduje powstawanie w strefie pracy narzędzia mikrospękań, które w pewnym okresie czasu będą się rozwijać. Co za tym idzie, elementy tnące zużywają się szybko, a w niektórych przypadkach łamią się i szybko ulegają uszkodzeniu. W tym przypadku skład strukturalny elementów tnących zmienia się, a sieć strukturalna w metalach ulega zniszczeniu, co jest przyczyną nitowania. Aby utrzymać sprzęt i narzędzia stosowane w naprawach w stanie gotowości do pracy, jednym z istotnych warunków jest szczególne dbanie o nie i dostosowywanie parametrów trybu. Niniejszy artykuł omawia zwiększanie wydajności narzędzia frezującego przy zastosowaniu czynników chłodzących w procesie frezowania różnych obiektów metalowych pozostawionych podczas awarii w otworze wiertniczym. Aby to osiągnąć, przetworzono dane doświadczalne, a w oparciu o analizę regresji uzyskano wzory matematyczne, które opisują proces temperaturowy zależny od różnych parametrów reżimu procesu ścierania, zależności te przedstawione zostały również w formie graficznej. Wykonano przekształcenie z regresji liniowej na regresję nieliniową. Uzyskane wyniki umożliwiają przewidzenie klasyfikacji i schematów konstrukcji otworowych narzędzi tnących oraz wybór materiałów kompozytowych dla wzmocnienia części tnącej.

3

Analysis of the surface roughness of native wood species depending on angular parameters of the cutting tool during milling in different conditions

Stefanowski S., Pinkowski G., Szymański W., Krauss A.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2018

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No. 103

13--17

EN

The presented study concerned the effect of technological parameters such as feeding speed and sharpness angle on the surface roughness of three native wood species: beech, pine and black locust. The sharpness angle was investigated in range of 40-55° during milling with various values of feeding speeds. Milling process was carried out with the use of bottom spindle milling machine and roughness measurements were completed using stylus profilometer. In order to analyze the results simple linear regression analysis was done. It has been stated that in milling process linear upward trend of the surface roughness occurs with an increase in the feeding speed. However, the characteristic of this feature depends on the sharpness angle and wood species. In case of the sharpness angle, the best results were obtained for an angle in range of 40-45°. Designated linear regression lines were characterized by high coefficient of determination.

4

Usefulness of Modal Analysis for Evaluation of Milling Process Stability

Pieśko P., Zawada-Michałowska M.

Applied Computer Science

|

2017

|

Vol. 13, no 1

75--84

EN

The paper presents evaluation of modal analysis usefulness for deter-mination of milling process stability. In the first phase of the study experi-mental modal analysis was performed and using CutPro 9.5 software, stability lobes were generated. In the next step, machining tests were carried out. The last stage of the experiment involved verification of modal analysis usefulness for evaluation of milling process stability based on sur-face roughness measurements. Conducted research allowed to state that modal analysis can be a useful tool for determining milling process stability.

5

Monitoring of cutting conditions with the empirical mode decomposition

Wolszczak P., Łygas K., Litak G.

Advances in Science and Technology. Research Journal

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2017

|

Vol. 11, no 1

96--103

EN

In this paper, we apply empirical mode decomposition by Huang and Hilbert to transform signals recorded during a milling process. Vibroacoustic sensors recorded vibrations of a tool-workpiece system while milling with the end mill of a special shape of “Hi-Feed”. The results of Huang-Hilbert analysis provide the information about amplitudes and frequencies of empirical modal components. Application of Huang-Hilbert transform to cutting conditions monitoring allows the separation of various vibration components caused by phenomena associated with the drive system and the machine components. Therefore, the analysis highlights vibrations caused by known sources of vibration, such as spindle speed, the number of teeth of the cutting tool or the frequency of vibration tools. Furthermore, signal components generated in the cutting zone were identified. The resulting information helps to assess the working conditions of cutting tools, selection of cutting parameters and tool wear monitoring.

6

Strategia sekwencyjnej obróbki powierzchni o zmiennej krzywiźnie z zastosowaniem frezów kulistych i elastycznych krążków ściernych

Plichta J., Baran J.

Mechanik

|

2016

|

R. 89, nr 8-9

1082--1083

PL

Przedstawiono koncepcję strategii obróbki kształtującej i wygładzającej powierzchni o zmiennej krzywiźnie. Celem autorów było zminimalizowanie łącznego czasu obróbki z uwzględnieniem nierówności powierzchni po frezowaniu frezem kulistym i jej wygładzaniu krążkiem ściernym z agregatami Trizact™.

EN

The article presents the concept of the strategy of shaping and sanding process of the free form surfaces. The main aim is the minimization of the sum of machining time with the consideration of surface roughness after ballend milling process and sanding process with abrasive discs with Trizact™ grains.

7

Cutting parameters and vibrations analysis of magnetic bearing spindle in milling process

Bouaziz A., Barkallah M., Bouaziz S., Choley J. Y., Haddar M.

Journal of Theoretical and Applied Mechanics

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2016

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Vol. 54 nr 3

691--703

EN

In modern production, milling is considered the widespread cutting process in the formatting field. It remains important to study this manufacturing process as it can be subject to some parasitic phenomena that can degrade surface roughness of the machined part, increase tool wear and reduce spindle life span. In fact, the best quality work piece is obtained with a suitable choice of parameters and cutting conditions. In another hand, the study of tool vibrations and the cutting force attitude is related to the study of bearings as they present an essential part in the spindle system. In this work, a modeling of a High Speed Milling (HSM) spindle supported by two pair of Active Magnetic Bearings (AMB) is presented. The spindle is modeled by Timoshenko beam finite elements where six degrees of freedom are taken into account. The rigid displacements are also introduced in the modeling. Gyroscopic and centrifugal terms are included in the general equation. The bearings reaction forces are modeled as linear functions of journal displacement and velocity in the bearing clearance. A cutting force model for peripheral milling is proposed to estimate the tool-tip dynamic responses as well as dynamic cutting forces which are also numerically investigated. The time history of response, orbit, FFT diagram at the tool-tip center and the bearings dynamic coefficients are plotted to analyze dynamic behavior of the spindle.

8

Analysis of mechanical characteristics of face milling process of Ti6AI4V alloy using experimental and simulation data

Nieslony P., Grzesik W., Bartoszuk M., Habrat W.

Journal of Machine Engineering

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2016

|

Vol. 16, No. 3

58--66

EN

This paper presents experimental and 3D FEM simulation results obtained for the Johnson-Cook material constitutive model and variable cutting conditions. Face milling tests were carried out using a Ti6Al4V titanium alloy as the workpiece and coated carbide indexable inserts. CAD models of the cutting tool insert and the face milling head were generated and implemented into FEM package used. The machining conditions were selected based on real production data from aerospace sector. In particular, changes of power and specific cutting energy were analyzed in terms of the rotation angle of the milling head and the ratio of the uncut chip thickness against the cutting edge radius.

9

Analiza porównawcza możliwości uzyskania drobnego uziarnienia w młynie elektromagnetycznym i kulowym z uwględnieniem optymalizacji kosztów transportu surowca

Wołosiewicz-Głąb M., Foszcz D.

Logistyka

|

2015

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nr 4

9930--9938, CD3

PL

W artykule dokonano oceny pracy dwóch rodzajów młynów służących do przeróbki surowców, młyna kulowego i elektromagnetycznego. Przedstawiono charakterystykę parametrów konstrukcyjnych, przeprowadzono analizę porównawczą efektywności rozdrabniania obu młynów. Zdefiniowano proces mielenia. Uwzględniono również koszt transportu surowca do mielenia, stosowanego w trakcie pracy tych młynów, biorąc pod uwagę że każdy z nich cechuje się inną wydajnością i konstrukcją.

EN

The paper assesses the work of the two types of mills used for processing of raw materials: electromagnetic and ball mill. The characteristic design parameters and a comparative analysis of the two mills grinding efficiency have been presented. The milling process has been defined. Also included is the cost of transporting of the raw material, which is used during the grinding process in both of these mills, given that each mill has a different performance and design.

10

Influence of Cutting Conditions on Temperature Distribution in Face Milling of Inconel 718 Nickel-Chromium Alloy

Grzesik W., Nieslony P., Habrat W., Laskowski P.

Journal of Machine Engineering

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2015

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Vol. 15, No. 2

5--16

EN

This paper presents 3D FEM simulation results obtained for the milling operations on a nickel-chromium alloy (Inconel 718) using the Johnson-Cook material constitutive model and variable cutting conditions. Face milling tests were carried out using silicon-aluminum-oxygen-nitrogen (SiAlON) ceramic cutting tools inserts. The machining conditions were selected based on real production data (cutting speed of vc=750 and 800 m/min, feed of f=0.1, 0.125 and 0.15 mm/t, depth of cut of ap=1, 1.5 and 2 mm). The FEM simulations include the maximum and average values of the cutting temperature. They were compared with experimental data obtained by using the high speed infra-red camera.

11

Experimental and simulation investigations of face milling process of Ti-6Al-4V titanium alloy

Niesłony P., Grzesik W., Habrat W.

Advances in Manufacturing Science and Technology

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2015

|

Vol. 39, nr 1

39--52

EN

This paper is focused on the finite element analysis of machining of Ti6Al4V titanium alloy in a nonorthogonal (3D) face milling process. The study was conducted for face milling with the cutting speed of 80 m/min, depth of cut of 1 mm, cutting width of 10 mm and different feed rates. The FEM simulations include the cutting force components and average maximum cutting temperatures. The simulation results were compared with experimental data obtained for similar milling process configuration. It was found that the kind of FEM constitutive model influences the force and temperature values. In this case the cutting force has a better match with experimental data when using the JC model. On the other hand, a good fitting for both feed and passive forces was achieved for the PL model. Additionally, a very good fitting for the cutting temperature using PL FEM model was obtained. It was also found that the feed rate has a significant effect on the average interface temperature and can be modelled by using FEM material models presented in the article.

PL

W pracy prowadzono analizę wyników symulacji procesu frezowania walcowo-czołowego stopu tytanu Ti6Al4V, w układzie nieortogonalnym (3D) z zastosowaniem metody elementów skończonych. W procesie frezowania płaskiego stosowano prędkość skrawania 80 m/min, głębokość skrawania 1 mm, szerokość skrawania 10 mm, dla różnych wartości posuwów. Przy użyciu MES określono wartości składowych sił skrawania oraz maksymalną wartość temperatury skrawania. Walidację wyników symulacyjnych i badań eksperymentalnych prowadzono dla takich samych wartości warunków obróbki. Stwierdzono, że rodzaj konstytutywnego modelu MES ma wpływ na wartości siły i temperatury skrawania. W tym ujęciu dobrą zgodność danych symulacji normalnych i eksperymentalnych, dla przypadku składowej głównej siły skrawania, uzyskano przy zastosowaniu modelu JC. Natomiast lepsze dopasowanie dla składowej posuwowej i odporowej (pasywnej) uzyskano dla modelu PL. Dodatkowo dobre dopasowanie wyniku symulacji i eksperymentu, dla temperatury skrawania, uzyskano także dla modelu MES typu PL. Stwierdzono, że posuw ma znaczny wpływ na wartość średniej temperatury skrawania. Modelowanie tych oddziaływań można realizować, stosując modele materiałowe MES przedstawione w pracy.

12

Chatter in milling of composites: simulations and diagnostic

Rusinek R.

Journal of Machine Engineering

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2010

|

Vol. 10, No. 3

30--36

EN

The study focuses on the problem of milling stability, specially dedicated for materials with heterogeneous mechanical properties like composite materials where specific cutting force depends on fibre location and orientation. Classical model of regenerative milling is completed by adding a harmonic function which represents a change of specific cutting force. Finally, an influence of specific cutting force modulation on process stability is presented and vibrations analysis is performed.

13

Intelligent control system for HSM

Vallejo A., Morales-Menendez R., Elizalde-Siller H.

Journal of Automation Mobile Robotics and Intelligent Systems

|

2009

|

Vol. 3, No. 3

54-63

EN

Next-generation of High-Speed Machining (HSM) systems demand advanced features such as intelligent control under uncertainty. This requires, in turn, an efficient administration and optimization of all system's resources towards a previously identified objective. This work presents an optimization system based on Markov Decision Process (MDP), where an intelligent control guides the actions of the operator in peripheral milling processes. Early results suggest that MDP framework can cope with this application, yielding several benefits, which are discussed in detail. Future work will address the full integration of the developed optimization scheme within a commercial machining center.

14

Optimisation of up- and down-milling processes for a corner feature

Dotcheva M., Millward H.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

|

2008

|

z. 73 [253]

73-80

EN

This paper presents the specifics of the two types of end-milling, up- and down-milling, in the context of process planning of a finishing operation for machining complex pocket features. An optimisation mechanism is used for a pocket type of end-milling operation with the aim of comparing the results from up- and down-milling when the same process constraints have been applied. Two sets of cutting conditions have been generated and analysed for each type of end-milling. The first cutting condition has constant parameters for the entire tool path, derived from the worst case of cutting, representing the usual process planning approach The second set of cutting conditions represents the optimised process. The predicted results were verified through experiments. The optimised, measured cutting parameters, when machining the critical corner, accurately demonstrate the important changes in magnitude and direction of the radial cutting-tool deviation and surface error

15

Wybrane problemy pracy układów przygotowania rudy do flotacji w zakładach wzbogacania rud KGHM Polska Miedź SA

Kasińska-Pilut E.

Górnictwo i Geologia

|

2008

|

T. 3, z. 3

19-26

PL

W artykule zaprezentowano zadania operacji wstępnych stosowanych w KGHM Polska Miedź SA, w celu przygotowania rudy do flotacji. Opisano czynniki wpływające na efekt mielenia oraz przedstawiono symulację wpływu zmiany uziarnienia nadawy na efekt energetyczny procesu.

EN

The necessities of the modernization of ore preparation processing are presented. The direction of the research works are proposed.

16

Wpływ parametrów procesu frezowania na jakośc obrabianej powierzchni oraz poziom drgań

Łuczko J.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

|

2005

|

z. 65 [222]

273-280

EN

This paper presents an analytical model of the milling process. Using the relations between machining parameters and kinematic parameters, the delay differential equations were derived, describing the motion of the system. The influence of selected parameters on the character of vibration, on the level of vibrations and the state of the workpiece surface were studied. Different types of vibration are illustrated by plots of time histories, phase portraits, stroboscopic portraits and bifurcation diagrams.

17

Zmniejszenie energochłonności procesu mielenia węgla metodami fizykochemicznymi

Kadlewicz K.

Wiadomości Górnicze

|

2005

|

Vol. 56, nr 7-8

373-379

PL

W artykule przedstawiono wyniki badań zastosowania wybranych substancji powierzchniowo czynnych w procesie mielenia miałów węglowych w młynach kulowych. Przedstawiono - stosowaną w trakcie doświadczeń - metodykę i aparaturę. Omówiono mechnizmy działania i wpływ aktywatorów na zmniejszenie energochłonności mielenia. Zaprezentowane wyniki dotyczą pomiarów zużycia energii, zmian składów ziarnowych i badań mikroskopowych przemiałów.

EN

The article present the results of investigations on application of selected surface active substances in the process of fine Coal milling in ball mills. The methodology and apparatus - used in the course of investigations - was presented. The mechanism of action and impact of activators on decrease of energy intensity of milling was discussed. The presented results regard the measures of energy consumption, changes in grain size content and investigations on microscopic milling.

18

Skanowanie i symulacja frezowania powierzchni walcowych

Filipowski R.

Przegląd Mechaniczny

|

2004

|

nr 5

19-24

PL

W artykule przedstawiono metodę tworzenia punktów leżących na krzywej ekwidystantnej (ofsetowej) względem powierzchni pomiarowej. Do tego celu zastosowano metodę interpolacji oraz wybrano wielomiany Newtona drugiego stopnia. Dla zmniejszenia błędów oddziaływań losowych podczas pomiaru skaningowego dobierano punkty do definiowania kroczących parabol ze zbioru pomiarowego, na zewnątrz typowego przedziału o długości 1 mm w układzie kartezjańskim lub 1 stopień w układzie biegunowym. Uzyskane punkty leżące na krzywych offsetowych wykorzystuje się do celów pomiarowych lub do odtwarzania powierzchni. Symulację frezowania powierzchni, której model uprzednio skanowano, wykonano w systemie PC-AT, tj. w systemie CAD/CAM firmy NCSI N/C SOFTWARE INC., Ashville, USA.

EN

As a result of scanning process a set of points has been obtained and then the offset curve has been determined as the distance of the probe radius from cylindrical surface. The author presented the method of calculating of points that are situated on the offset curve. The Newton polynomial was used in the inter- polation method. In order to reduce the random errors arising during the scanning process, it was suggested to select the points outside the typical interval of 1 mm length for orthogonal coordinate system and Idegree for the polar coordinate system. The calculated points on the offset curve can be used for the purpose of inspection or reverse engineering of cylindrical surfaces. Simulation of milling process of cylindrical surfaces was elaborated using the commercial system PC-APT developed by the CAD/CAM NCSI N/C SOFTWARE, INC. Ashville USA.

19

Wpływ drgań na proces frezowania

Łuczko J.

Czasopismo Techniczne. Mechanika

|

2004

|

R. 101, z. 13-M

75--83

PL

W pracy przedstawiono model procesu frezowania walcowego. Wykorzystując ścisłe związki geometryczne między parametrami skrawania i parametrami kinematycznymi, ruch układu opisano równaniami różniczkowymi z odchylonym argumentem. Zbadano wpływ prędkości obrotowej, prędkości posuwu oraz głębokości skrawania na poziom emitowanych drgań oraz na stan obrabianej powierzchni. Wykazano możliwość wzbudzania się w pewnych zakresach prędkości obrotowej drgań nieregularnych - prawie okresowych i chaotycznych. Ruch układu zilustrowano przebiegami czasowymi oraz na płaszczyznach fazowych.

EN

This paper presents an analytical model of the milling process. Using the exact relations between machining parameters and kinematic parameters, the delay differential equations were derived, describing the motion of the system. The influence of the rotational velocity, the feed and the depth of cut on the level of vibrations and the state of the workpiece surface were studied. The possibility of exist of ąuasi-periodic or chaotic oscillations for some intervals of rotational velocity were showed. The motion of the system is illustrated by numerical examples. The results of calculation are presented as time histories and as the lines on phase plane.

20

Simulation of the heat field of a proceeded element while austenitic steel milling

Feldshtein E., Kamiński W. L.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

|

2000

|

z. 54 [179]

27-36

EN

The outcomes of simulation of heat fields by a finite element method at milling austenitic steel 00H17N14M2 are reduced. The solution of the task of non-stationary nonlinear heat conduction has allowed finding allocation of temperatures in surface layers of a detail of the composite form in velocity function of cutting and position of blade of a burr.