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Force loading of milling tools during the machining process
Procházka, Luděk ; Slaný, Martin (referee) ; Polzer, Aleš (advisor)
The thesis deals with the problem of force loading during machining of thin-walled parts. In the theoretical part, the force load applied during milling and the possibility of measuring of the force loading during milling is analyzed. Further the work focuses on the machining of thin-walled parts, problems in machining of these parts and the possibility of eliminating these issues. The practical part deals with the design and realization of the measurement of the force load on the selected components. The thesis also presents a comparison of the simulation model of deflection of thin-walled parts with the values measured in real machining.
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Prediction of suitable cutting conditions for machining of main steels
Beneš, Ondřej ; Fiala, Zdeněk (referee) ; Jaroš, Aleš (advisor)
In this thesis is described machining of barrel steels and determination of the most suitable cutting conditions for this process. In the theoretical part was characterized cutting process and explained problems of VBD wear, chip formation and roughness of the surface. There were also explained most common cutting materials and in the last part were described CVD and PVD coating methods. In the experimental part was measured force load during turning. There was also tested eight carbide cutting inserts from SECO TOOLS. During the tests were measured additional surface roughness values and taken chip samples as well. From the evaluated load force data were determined optimized cutting conditions for machining barrel steels and most suitable type of cutting insert.
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Analysis of the force loading of the end mills with PCD considering their sharpening
Trčka, Tomáš ; Kalivoda, Milan (referee) ; Polzer, Aleš (advisor)
Measurement of the force loading is a significant type of measurement in mechanical engineering applied to analyse important aspects in the machining process. In addition to the determination of specific material constants, it is possible to analyse, for example, various machining strategies, geometries of tools or the degree of wear of the cutting edges of cutting tools. This master’s thesis deals especially with the last two mentioned aspects which are subjects of an experiment on end mills with PCD inserts sharpened by a different technology. In the introductory part the cutting forces are theoretically analysed along with their measurement possibilities and the technology of the production of the mills including their sharpening – WEDM and EDM-G. One chapter is concerned with the milling of plastic materials, as PVC was the material used for the workpiece during the experiment. The first experimental part is devoted to the analysis of sharpened tools followed by the measurement of forces using the piezoelectric dynamometer and the subsequent analysis of the influence of the different tool geometry. The last conducted experiment monitors how the overall cutting forces of individual end mills sharpened by different technology changed over specific milling time slots.
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On the milling technology of thin-walled parts for aerospace industry
Ohnišťová, Petra ; Polzer, Aleš (referee) ; Píška, Miroslav (advisor)
This thesis is focused on the analysis and on the design of the milling technology of the components for the aerospace industry which are characterised by a high aspect ratio, reduced stiffness and all covered by a high demand on the fatigue performance. This work includes the experimental verification of the proposed technology using CNC machining center, evaluation of surface structure using optical high-resolution 3D surface measurement system ALICONA, analysis of the force loading using KISTLER device, fatigue testing and fatigue fracture analysis.
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Analysis of the force load when machining of aluminum alloys with monolithic mills from Cemented Carbide
Koubek, David ; Kalivoda, Milan (referee) ; Polzer, Aleš (advisor)
The aim of this thesis is to create the proposal and expansion of knowledge in the field of experimental measurement of force load when milling thin-walled parts made of aluminum alloy monolithic cylindrical shank cutter of cemented carbide (hereinafter referred to as CC). It also discusses the theoretical analysis of the forces generated during milling, and practical approaches to their measurement experiments. This work also deals with the analysis of aluminum and its alloys. The next chapter describes the appropriate strategy for the machining of thin-walled components including defining the problems, that can complicate machining thin walls. The practical part deals with prediction and a following suggestion of the experiment measuring the power load. The last section is devoted to the practical implementation of the measurement of forces during the milling of thin-walled parts with subsequent evaluation and comparison of strength for the record selected from CC carbide tools, including evaluation of roughness parameters.
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New Milling HSS Cutters for Roughing Operations
Jaroš, Aleš ; Janáč, Alexander (referee) ; Chladil, Josef (referee) ; Píška, Miroslav (advisor)
Dissertation thesis is focused on development, design and production of the new milling cutter which is used for roughing operations. High-speed steels, coating technology and milling technology are described in first chapters of dissertation thesis. The main part of this thesis is the design of the new milling cutter that has been designed on the basis of the machining simulation. The milling cutter is designed as a three-flute cylindrical end mill made of high speed steel. The each flute is composed of two special compensation edges. The compensation edges are used for reducing (at best suppression) tensile stress in the heel of the tooth. The milling cutter was made by lost wax technology, followed by grinding and thermal treatment. New designed tools were deposited by PVD coatings (e.g. (Al,Ti)N). Standard catalog milling cutters (producer ZPS - milling tools, Zlín, Czech Republic) were used for comparison the designed milling cutter. Carbon steel CSN 41 2050 (DIN 1.1191) was used for milling, which was carried out with using process liquid. The monitored parameters were force loading, flank wear and tensile stress during milling. The dynamometer Kistler was used for measuring force loading and data obtained during machining was used for stress analysis.
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An Experimental Study of the Impact of Passive Forces of Cutting on a Machined Surface
Slaný, Martin ; Janáč, Alexander (referee) ; Bumbálek, Bohumil (referee) ; Píška, Miroslav (advisor)
This dissertation thesis focuses on the evaluation of modern machine tools, especially tools for finishing operations, with which the effect of the passive force components on the machining process is evaluated. The thesis will examine the analysis of creating chips and circumstances that accompany this process and substantially involve the formation of a new surface. The analysis of the process of the recording of the power load of the MT3 tool takes place in the experimental part of the thesis. MT3 is a reaming head intended for finishing holes at high cutting speeds (100-200 m.min-1) with removal of small cross section AD (0.024 mm2) chips. Particular attention is paid to the newly created profile from the surface after machining and evaluation of changes in geometry and loading of the cutting edge, which is significantly reflected in the establishment and the development of passive forces.
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An experimental study of the impact of passive forces of cutting on a machined surface
Slaný, Martin ; Píška, Miroslav (advisor)
This dissertation thesis focuses on the evaluation of modern machine tools, especially tools for finishing operations, with which the effect of the passive force components on the machining process is evaluated. The thesis will examine the analysis of creating chips and circumstances that accompany this process and substantially involve the formation of a new surface. The analysis of the process of the recording of the power load of the MT3 tool takes place in the experimental part of the thesis. MT3 is a reaming head intended for finishing holes at high cutting speeds (100-200 m.min-1) with removal of small cross section AD (0.024 mm2) chips. Particular attention is paid to the newly created profile from the surface after machining and evaluation of changes in geometry and loading of the cutting edge, which is significantly reflected in the establishment and the development of passive forces.
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Cutting force analysis when 5-axis milling
Dvořáček, Jan ; Kalivoda, Milan (referee) ; Polzer, Aleš (advisor)
The diploma thesis is focused on machining using the ball-end shank mill. Content of the preliminary part of the work is a shank mill characteristic and a consequent part shows a splitting of ball-end milling cutters, its application, the cutting tool geometry and a characteristic signs of machining. The cutting force model of the ball-end mill is presented as well. A part of proposed model is the conversion of the resultant force too. Practical part is aimed at cutting force analysis of the ball-end mill and the main purpose of this part is a quantification of the cutting force for different work piece tilt angles while milling is performed.
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Analysis of the coated carbide cutting inserts
Zdráhala, Radim ; Kolář, Ladislav (referee) ; Fiala, Zdeněk (advisor)
Bachelor thesis is focused on the analysis of the cutting and specific cutting forces during face milling of coated and uncoated exchangeable cutting inserts (VBD). The theoretical part deals with the characteristic of the milling process, coating of cemented carbides and last but not least deals with methods for measuring cutting forces. The experiment is described in the experimental part that also includes evaluation of load forces coated and uncoated exchangeable cutting inserts during changes in cutting conditions. Finally is performed the comparison of values coated and uncoated VBD for flank wears and load cells.
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