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Automatic workpiece exchange is one of the important parts of every flexible manufacturing system. This part largely allows complete automation of the component's production cycle. It also greatly contributes to a significant reduction in the workpiece clamping times and contribute to a reduction in the downtime during the machining process. It also allows eliminating a human factor from the production process, thereby contributing to greater machine utilization and higher machining productivity. This article describes certain modifications of interchangeable pallet system designated for specific training CNC machine tool EMCO Concept Mill 105 situated in the laboratory at the Department of Automation and Production Systems. This machine has considerably limited workspace and length of feeds which are the most limiting parameters during design. Mentioned modifications allow manipulating with designed pallets with the industrial robot or special manipulator instead of previously designed manual handling.

The production of precise castings by investment casting becomes an increasingly important manufacturing technology and many of isues of this method have to be addressed. This paper deals with evaluation of critical points on wax patterns of small blades. After the casting of certain product, the casting had a deviation from the required dimension. Investigation revealed that the effect on the resulting dimensional deviation is not only the casting process but also the wax pattern injection process itself. The engine and turbine blades are one of the most important parts in turbine or aircraft engine machinery. Casting deformation is an important feature of evaluation the quality of the turbine blade. In order to control the deformation of the turbine blade during investment casting, a novel compensation method based on reverse deformation was proposed in this study. The article investigates and evaluates critical points for deformation of the blades after their production on wax-press machine. In addition, the effect of the pre-deformation preparation and the human factor influencing effect during assembly is evaluated with the main aspect of not machining all surface of small blades.

Forestry is characterized by a diversity of natural conditions, which need to be adapted not only to the selection and application of technological processes, but also to the materials used in the construction of individual parts of the equipment. The article deals with the possibility of replacing steel elements with aluminium ones for selected parts of the adapter frame designed for liquidation of forest fires. The aim is to achieve a gradual reduction in its total weight. The aluminium sheet AlSiMgMn EN AW-6082 was selected a replacement for the steel parts. The filler material was solid wire AlMg5Cr. Welding was performed by the MIG method. The selected welding parameters should guarantee the creation of a quality joint that can replace steel weld joints, while respecting the demands placed on them. Weld joints were analysed by macroscopic analysis, measurement of hardness by HV1 and SEM analysis of welded joint with EDX analysis. The results of the laboratory experiment show that by the chosen welding procedure with given parameters, quality welded joints were achieved. After further analyses, these weld joints can be recommended as a substitute for the previously used weld joints of steel structures.

Presented research paper is focused on the development of carbon fibre wheel. Considering development and construction of wheels for the automotive and motorcycle industry, low weight is one of the most significant factors. In the case of rotating components, the imbalance of the assembly is a problem. This fact affects handling of the vehicle or wheel behavior under the load, for example in the point of turning, acceleration or drive on damaged road. Determination of the most appropriate material composition (sequence) is primarily the main problem of composite material application. Correct design of material composition and also lay-up diagram is determined by material characteristics and strength requirements. A suitable solution is in the application of a group of input material structures creating hybrid composite. Specific combination of various input materials (aluminum ring, 3D printed plastic honeycomb core and carbon fibre composites) guarantees and ensures the fulfilment of the strength requirements which are determined during each particular application. The main aim of presented paper was to design material composition and shape of carbon fibre wheel that were subsequently verified by successful manufacturing process.

During the operation, a slewing bearing is always subjected to a set of combined loads. It is the source of deformation of ball-raceway contacts, rings, and even supporting structures. In practice, deformation of rings and supporting structures is often neglected for simplification, that is, they are supposed to be ideally stiff. To take elasticity of rings and supporting (fixed) structures into consideration, the finite-element method (FEM) is applied. In slewing bearings, a great number of contact pairs are present on the contact surfaces between the rolling ele-ments and raceways of the bearing. In order to improve the computational efficiency of load distribution of large roller slewing bearing, a computa-tional model using one-dimensional finite elements (nonlinear elements) is presented in this paper. In this model, each roller is simulated by a group of nonlinear elements truss, which has the same load-deformation perfor-mance with solid roller-raceway contacts. The results show that a group of parallel springs can be used to replace the solid roller and simulate the line contact performance between the roller and raceway. Obtained results are presented as graphs.

Lattice structures are one way to reduce the weight of a component while respecting its strength requirements. These structures are based on cubic cells, therefore, they are not fully applicable to rotating parts which should be lightweight. This article particularly addresses this issue. A solution is sought for how to adapt lattice structures for a milling cutter. The final redesign of the topology allows a continuous flow of generated stress into the whole body of the cutter. Further, the solid part of the milling cutter is modified for Metal Additive Manufacturing (MAM) and the functionality of the optimised cutter is verified by Finite Element Analysis (FEA). The results of the analysis are compared with a conventional cutter with the same outer shell. The findings from the static analysis indicate that the milling cutter can be considered to be competitive.

Despite the fact that Titanium alloys are frequently used in medicine, aviation industry and also in machine manufacture due to their strength and resistance against external influences. Moreover, their innovation to obtain better and more suitable parameters still proceeds. Regarding their mechanical properties, they are considerably less machinable which affects surface integrity of a machined area. That is why a proper selection of a machine tool and cutting conditions are extremely important. This paper deals with a finishing grinding process of the material VT9 by means of specific grinding wheels 5TG and DIA under specified cutting conditions. Based on experimental verifications it can be defined which grinding Wheel is more suitable in specific conditions with an impact on integrity of the ground surface. From the standpoint of grinding parameters such as surface roughness, thermal impact and acting of cutting forces as well as arising residual stress in the surface layer are key for surface integrity.

The aim of the paper is to describe the design of the manipulation system for the raw ceramic chimney pipe raw blank to avoid deformation of the pipe during handling and to increase the productivity of the manufacturing process. The process of manufacturing of a ceramic chimney pipe begins with extrusion of the raw refractory material. The extruded semi-finished product is then processed and then transferred by hand to a kiln car on which it is dried and fired. It is this manipulation that heavily contributes in the deformation of the fired chimney pipes. Due to the low stiffness of the raw ceramic chimney pipe, deformation occurs by manual handling. In order to avoid these deformations, it is necessary to design a suitable concept and construction solution of the manipulation system. Due to the nature of the chimney pipe, the automation of manipulation is rather difficult. The pipe is very soft in the raw state, its surface is rough, wet and greasy. This paper deals with the design of an optimal solution for the manipulation of ceramic chimney pipes, which will prevent the chimney pipe from deforming, negatively affecting its quality and making it possible to increase the productivity of ceramic chimney pipes production.

The presented article deals with the thermal energy influence on various types of construction steels during laser beam cutting. When the material is cut by a laser, the workpiece is subjected to intensive thermal load. Due to this influence, steels hardness is increased and the structure is changed.
The aim of this study is to verify how the thermal energy influences the surface layer of material during laser cutting. The influence was studied on data measured by DSI (depth sensing indentation) micro-hardness method. Each sample was subjected to cross-section from edge to the distance of 20 mm from the edge measurement. To evaluate surface layers during laser cutting, three types of steels with different carbon content 1.0038 (S235JR), 1.1203 (C55) a 1.7131 (16MnCr5) were chosen. The main objective was to determine the distance from the cutting point to the material when cutting with a laser beam, how its micro-mechanical properties and structure change or the distance from the cutting point to the component's hardening.

This paper deals with the causes of failure of total hip replacement. Hip joint replacement is one of the most frequently used surgical procedures worldwide. More than 200,000 surgeries are performed only in Europe each year, following early attempts by John Charnley. Currently, more than 340 of the total 4431 implants per year are reoperated in Slovakia. Despite the excellent properties of the titanium alloy, endoprosthesis often fails and the hip replacement is necessary. Common causes are overloading and cracking, static or dynamic. Other causes of failure include injury, implantation failure, manufacturing inaccuracies, and non-compliance with the manufacturing process.

The main topic of this paper is the presentation of the keynote of implementation of the newly designed steering mechanism for a tricycle with the electric powertrain with two wheels on the rear axle. On the present, three-wheeled road vehicles with two wheels on the rear axle are wholly dependent on the standard steering mechanism, which main task is the rotation of a front wheel about the steering axis in order to ensure the change of direction in curves. These vehicles are characterised by the relatively poor overturning immunity in a curve. Therefore, in our workplace the new steering mechanism was developed, which is intended to be mounted just in such three-wheeled vehicles construction. The main principle feature of our innovative steering mechanism consists in the additional lateral movement of the front wheel of a vehicle, when it is driving in a curve. Thus, a tricycle using this newly designed steering system can run in curves at greater speed and driving is safer. In this paper, there are presented the working principle of the newly designed steering system as well as dynamic analyses of a three-wheeled vehicle when it is running in curves.

This work aimed to characterise microstructure and mechanical properties of polymer composite samples. The main task was to adapt the well-known techniques of metallography (i.e. sample preparation and microscopic examination) to documentation of multi-component polymer materials and to optimize the methods of light and electron microscopy for this particular purpose. There were several issues (e.g. low melting point, absence of electrical conductivity), which made the process different from metal samples preparation and observation and which needed to be addressed. Various mounting resins were tested for the samples to find the suitable one, then the process of grinding and polishing was optimized and finally the microstructure was documented using light and scanning electron microscopy (SEM). Samples in the undeformed state were examined as well as the samples subjected to tensile test at different temperatures. Prior to the microscopic observations the material was analysed using methods of thermal analysis (TG A, DSC) and infrared spectroscopy (FT-IR). The tensile tests were employed not only to determine the mechanical properties but also to obtain deformed samples for further microscopic observation.

Hardness tests enable to determine one of the main mechanical properties of the material, namely hardness. For hardness testing, it is possible to use either conventional desk hardness testers or the currently increasingly used portable hardness testers. The paper is focused on determination of the accuracy and reliability of static (desk) and dynamic (portable) hardness testers. The paper deals with the measurement of hardness of calibration hardness plates by 4 different methods (Brinell, Vickers, Rockwell and Leeb) with using 5 different hardness testers (3 desk and 2 portable). The hardness values measured by the different hardness testers were compared to the reference hardness listed in the calibration hardness plates and consequently, the accuracy of these measurements was evaluated. The aim of the work has been to determine the accuracy and reliability of portable hardness testers in comparison with desk hardness testers.

An approach to increasing the efficiency of the diamond grinding of hard-working materials is shown. A well-founded choice of characteristics of the diamond-bearing layer of the tool can be made through analyzing the results of 3D modeling of the processes of formation and operation of the diamond-bearing layer and stresses upon it. Diamond wheels formed on porous ceramic binders are investigated and discussed.

Previous work has proposed a process for implementing a lattice structure into a milling cutter body based on clustering in the milling cutter with modified main dimensions of a BCC cubic lattice structure cell. A finite element analysis model has been created to predict the strain and deformation in the struts of the lattice. The prediction made according to static loads demonstrates that the concept of a lightweight cutter meets the strength requirements, though its stiffness does not reach the fully-filled version. The methodologies for creating the FE model are described in this paper. HyperWorks with OptiStruct were used for these analyses. Local stiffness could be improved by varying the strut diameter or using a different type of basic cell for the lattice structure in problematic locations, especially in the area of the connection between the shell of the cutter and the lattice structures.

Vibrational properties of road vehicile are ussually evaluated according to two criterions, i. e. in terms of comfort for passengers and in terms of drive safety and roadway load. The topic of this article is focused on evaluation of passenger's ride comfort of a three-wheeled road vehicle. From the ride comfort point of view vertical vibration is decisive. Vertical vibration is given by obtained accelerations in given position on an assessed vehicle when it is driving on a road with various surface qualities within required time intervals. In the vehicle's design phase its vibrational properties are detected and evaluated by means of simulation computations on a virtual model. In our research we have assessed ride comfort of the three-wheeled vehicle, which were designed in our workplace. For purposes of dynamic analyses we have used multibody approach using Simpack software. The objective of this work is verification of the relevance of the current mounted suspension system for the greater driving speeds range of the three-wheeled vehicle and for different road qualities.

Aiming to study the working efficiency and stability of the loader, the hydraulic system of the loader is studied. Taking the ZL50 loader as the research carrier, the working conditions of the loader and the working principle of the hydraulic system are analysed at first. AEMSim software is used to simulate and analyse the hy-draulic system, and the necessity of using the algorithm to optimize the hydraulic system is put forward. Secondly, the mathematical model of key hydraulic system optimization is deduced, and genetic algorithm and neural net-work algorithm are used to optimize the analysis of the objective function, and the simulation results are compared and analysed again. The results show that the parameters optimized by GA and BP algorithm are better than the original parameters. Further analysis shows that the parameters optimized by GA algorithm are better than BP algorithm in smoothness.

The given paper is closely connected with the experimental and numerical modal analysis of the carbon composite plate damaged by cut. In relation to the tested carbon composite, modal analysis was performed by help of special measuring device Pulse 12. The mentioned device was supplied by company Brüel & Kjear and the experimental measurements were carried out using damaged and undamaged plate sample which were prepared from the mentioned material hereinbefore. The investigated and analyzed plates of carbon composite were made of six layers of carbon fibres and they were arranged under the angle 90º (it is like fabric material made off carbon fibres). The layers arranged in the given way were joined by epoxide resin MGS 285. The experimental measurement of eigenfrequencies of carbon composite plates was carried out using the undamaged and damaged sample with proportions 78 mm x 78 mm while ten measurements were performed for each one specified site of the sample. In relation to the damaged plate sample, there was cut in length of 20 mm in the centre border. The finite element method in the software system ADINA v.8.6.2 was used for numerical analysis of the eigenfrequencies.

This article deals with state-of-art in the field of handling machines intended for disabled people, which serve for disabled entry of such people and for people with delimited locomotion. It contains calculation of forces, which act in the mechanical system of an electric device during its operation in real conditions, changes of reactions depending on the load and the climbing angle as this solved handling machine will designed for negotiation of staircases. The objective is the functional calculation of a driving mechanism of a stair chair marked SA Alfa, i. e. the calculation of loading forces and their action on the driving mechanism. It will serve in the next step as an input for the calculation of a required power under conditions of occurance of maximal resistance forces, which will be determining factor for dimensioning of driving components of this device.

Adhesive bonding technology present a perspective method of various materials bonding and replacing conventional bonding e.g. welding. A geometric shape modification of bonding material and an adhesive reinforcing by glass fibres to increase tensile strength of adhesive bond was subject of this research. The bonding material was modified into preformed angles 5°, 10°, 15°, 20° and adhesive bond with 0° was se t as the etalon. The adhesive was modified by glass fibre with weight 80, 110 and 160 g.m-2. The research proved tensile strength increase from 4 to 48% by various preformed adherent angles. The research also proved tensile strength increase from 4,8 to 93,7% by adhesive reinforcing with glass fibres with various weight. Statistical analyse proved significant difference between measured values on significance level 0.05 (p < 0.05) i.e. influence of adhesive bond modification on mechanical properties was proved.

Topological optimization is the process of reducing part weight while respecting strength requirements. This paper focuses on its possible positive consequences for the machining process. The main aim is to carry out a survey to obtain knowledge that will be applied during the topological optimization of a milling tool. According to all the indicators, the efficient implementation of lattice structures into the milling concept has the potential to achieve a high level of innovation, since the functional weight reduction of the tool allows for higher dynamics of the cutting process. The modified rigidity of the milling cutter and vibration absorption can extend the life of the cutting edge, and such a milling tool would provide a competitive advantage on the tool market.

Microcellular injection molding is relatively new and progressive technology for production of lightweight constructions. The weight reduction, elimination of sink marks, internal stresses and deformation of products are the main advantages of this unconventional technology. On the other hand, decrease in mechanical properties and poor surface quality are the application restrictions. There are several aspects affecting formation of microcellular structure and final properties of injection molded products. As a one of the most important aspects there is used material. Therefore, the main goal of this article was investigation the influence of different types of thermoplastic materials on the microcellular structure formation and mechanical properties of products. Further, the influence of holding pressure on products quality was also evaluated.

Dynamic analysis of crank mechanism is realised by relaxation method, where a connecting rod is modelled with three manners. In the first case the connecting rod is modelled as a rigid body, in the second case this one is modelled with two mass points and in the third case the connecting rod is modelled with three mass points. Results of all manners of modelling are compared and evaluated.

The use of cutting fluid should positively influence on the quality of the machined surfaces and durability of cutting tools. However, during the machining the oil from the hydraulic system of the machine often gets into the cutting fluid, which can alter the properties of the cutting fluid. In scientific literature there is no information about the effect of the hydraulic oil entering the cutting fluid on the tool life and roughness in turning. In this regard, at the laboratory of the Department of Machining and Assembly of the Technical University of Liberec, there has been conducted a study to ascertain the effects of hydraulic oil getting into different types of cutting fluids during the turning of stainless steel.

Lightweight constructions are in demand for applications which require low weight accompanied by rigidity. From this perspective, lattice structures are an interesting design solution in conjunction with additive manufacturing technology. This study addresses promising lattice topologies. A range of metallic lattice structures was produced using Direct Metal Laser Sintering technology and the samples were exposed to uniaxial tensile load. During the tensile tests crack initiations and locations of the breaks were observed. The results clarify the weaknesses of the cellular lattices and reveal their maximum tensile load. First steps have been taken to meet the demand for optimized lightweight AM products.

To meet the need of high-speed steel roll grinding, a hydrostatic lubrication system for high-speed precision roller grinding head is designed and the dynamic performance of the system is simulated and analyzed in this study. The hydrostatic lubrication system was designed according to the lubrication characteristics of the eccentric sleeve and thrust bearing of the high-speed precision roller. Then the mathematical models of the main components of the system were established. And according to the schematic diagram of hydrostatic lubrication system, the dynamic performance of the lubrication system at high speed was simulated and tested. The simulation and experiment results show that the lubrication effect of the eccentric sleeve static chambers and thrust bearings is good, and the designed hydrostatic lubrication system is feasible.

To achieve much higher operation parameters of EAST device, some key components are upgraded. Fast control coil as one of the key components is updated by using novel stainless steel mineral insulation conductor and the turns are increased to 4, which means the coil's operation environment becomes more severe and larger loads will be encountered. The coil joint is apt to be destroyed in view of the potential defects during the fabrication. Given the numerous advantages, the induction brazing is being considered for the conductor joint connection. The copper mock up is used to carry out the feasibility analysis. Based on the structural size of copper tube, the brazing parameters are calculated and a 2 turns splitting induction coil is designed. Some influence factors effecting the induction efficiency are analysed. It will provide guidance for choice of power supply and the optimization design of induction coil. In addition, the induction experiment is launched and comprehensive joint performance tests are subsequently performed. The test results indicate the joint overall performance could satisfy the basic engineering design requirement, but also some defects are found and more study should be carried out and to further improve the brazing quality.

Thanks to their chemical and physical properties, the cutting fluids can significantly affect the process of machining - the use of cutting fluid reduces the roughness of the machined surface and increases the tool life. However, during the machining the oil from the hydraulic system of the machine often gets into the cutting fluid, which can alter the properties of the cutting fluid. In scientific literature there is no information on the effect of the hydraulic oil entering the cutting fluid on the tool life and roughness in machining of the structural steel. In this regard, at the laboratory of the Department of Machining and Assembly of the Technical University of Liberec, there has been conducted a study to ascertain the effects of hydraulic oil getting into different types of cutting fluids during the milling of structural steel.

An application of an adhesive bonding technology is limited by cyclic loading of an adhesive bond. The aim of the experiment is to clarify a fatigue behaviour (low-cyclic tests of the fatigue) of four structural two-component epoxy adhesives applied to an alloy AlCu4Mg. The aim of the research was to evaluate a service life of the adhesive bond in terms of its fatigue stressing at the quasi static shear test. From that reason values of a passing loading for low-cyclic fatigue test were chosen for tested adhesives, i.e. 25 %, 50 % and 75 % from a reference value of a maximum force gained at the static test according to CSN EN 1465. The critical value at the low-cyclic fatigue test was determined from the experiment results for the adhesive bond as 75 %. Most of the adhesive bonds did not reach 100 cycles at this value.
It is obvious from the results that the considerable change of the adhesive bond strength did not occur after 100 cycles at the passing loading corresponding to 25 % and 50 % of the average maximum strength of the adhesive bond. The average fall of the resultant adhesive bond strength was in the interval 3 % to 11 %.

An adhesive bonding technology is limited by a cyclic loading of an adhesive bond. The paper deals with a testing of a low-cyclic fatigue of single-lap bonds reinforced with glass beads (B159, a fraction size 90 ± 20 μm). The aim of the research is a study of a low-cyclic behaviour of structural adhesive bonds by means of a scanning electron microscopy (SEM). The research will contribute to a clarification of the fatigue behaviour (low-cyclic) of structural adhesive bonds. The aim of the study was to evaluate a service life of the adhesive bond in terms of its fatigue loading at a low-cyclic shear test. Values of a pulsating loading for the low-cyclic fatigue tests were chosen from this reason for tested adhesives from static tensile test determined a reference value of a maximum force gained at a statical test according to the standard CSN EN 1465. The number of cycles was 1000 at the 30 % strength reached at the static tensile test of the adhesive itself. The cumulative effect of the shear cyclic loading after 1000 cycles showed micro- and nanocracks in the area of the adhesive. The experiment results did not confirm the assumption that repeated cyclic loading could lead to the premature failure of the adhesive bond.