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The article deals with non-destructive measurement of the effective throat thickness of fillet weld with deep penetration in T-joint. Ultrasonic Phased Array technology is used to indirectly measurement of effective weld throat thickness. Phased Array ultrasonic systems utilise multi-element probes, which are individually excited under computer control. By exciting each element in a controlled manner, a focused beam of ultrasound can be generated. Software enables the beam to be steered. Two and three dimensional views can be generated showing the sizes and locations of any flaws detected. The results of Phased Array ultrasonic measurements are compared with the real results obtained from the real macrostructural analysis. The methodology is appropriate for verifying compliance with the design weld throat thickness in the production of steel structures.

The present paper deals with the metrology, especially with the legal metrology that is responsible for assuring the uniformity and correctness of measurements. In addition to the definition and explanation of the basic terms and principles applied in the metrology, the paper presents especially the results of the scientific and research work in the cross-disciplinary fields of the legal metrology in Slovakia, namely in design and realization of a new measuring system for the verification of the radar level gauges.

The effect of the T62 post-weld heat treatment on the tensile strength of AA6156-T4 friction stir welded joints is studied. To this aim, the 0.2% proof stress and the tensile strength of as-welded and post-weld treated joints as function of the rotating and welding speed was analyzed performing a complete factorial design with three levels for each studied parameter. Statistical analyses were carried out to establish empirical models of the tensile properties of the joints as a function of the studied welding parameters. The obtained models were validated through statistical tools such as Mallow's CP, S, R2 and R2(adj). The developed regression models can be effectively used to predict the mechanical proprieties of the joints at 95% confidence level.

This paper deals with research of the heat treatment of tool steels Böhler K 455, K605 that are determined for production of tools for minting circulation coins. The aim of the research was to determine the impact of introduction of innovative heat treatment on the structural parameters and lifetime of coining dies. Experimental part presents the results of purity evaluation at semi-products with use of EDX analyse of the non-metallic inclusions, also microstructure evaluation, measurement of the size austenite grain after application of innovative heat treatment also. After ending of analysis and evaluation of lifetime coining dies, new parameters of heat treatment for using at the production were proposed.

This research aims to solve the issues of limited measuring range and great accumulative error in the digital assembly of aircraft parts. In this paper, we propose the use of array visual measurement technology for the assembly of large aircraft parts. First, the visual measurement space for large aircraft parts assembly is determined. Second, the visual measurement model for large aircraft parts is constructed. Then, the differences that occur in real-time to the global coordinates can be calculated by using the pre-assembly feature points of large parts and the measurement tools of an array visual system. Finally, the real-time simulation of the aircraft assembly process is conducted in ADAMS by the secondary development of the software. In addition, errors between the real-time assembly and the design model are solved, and then transmitted to the mechanical actuators, which in turn adjust their attitude to complete the assembly of the large aircraft parts. The results show that array visual measurement technology for the assembly of large aircraft parts is feasible and efficient.

To increase the intensity of cooling the unconventional methods can be used, which enable to achieve quick and steady heat transfer from the injection mould and from the plastic product. This paper is devoted to the cooling method based on high cooling potential of liquid carbon dioxide that is included among the unconventional methods of mould temperature control system. The main objective of this paper is to evaluate the applicability of cooling with using liquid CO2 in the injection mould with regard to several aspects that have a direct impact on the final cooling efficiency. The practical experiment deals with the design of the shaped mould insert with the incorporated progressive cooling system by means of CO2 and its comparison with conventional tempering by water. The study is based on evaluations of the temperature profiles reached from thermocouples located in three positions in the injection mould and analysis of temperature fields measured on the surface of the product after its removal from the shaped insert. All the analyses were carried out for three cooling modes and before individual testing steps the technological parameters of cooling were optimized.

3D printing of metallic powders is a relatively new but increasingly used technology in a wide range of sectors. Design engineers are responding flexibly to new opportunities for production and components for 3D printing and are designing with respect to the advantages and limitations of this technology. Through the additive method of production, we can produce very specific components with complex shapes, both internal and external, which cannot be produced by conventional methods, thereby opening up new possibilities both in functional components and in their design.
This paper deals with the influence of critical parameters of metal laser sintering of metallic powders, particularly tool steel, on the geometrical accuracy of a component. Based on selected critical parameters, a component was designed that was printed on different devices and subsequently evaluated in terms of accuracy, surface quality and material properties.

The article describes the vehicle passability testing possibilities by the help of computational simulation with the usage of computing simulation system ADAMS AVT. The simulation calculations can help to find quick answers to basic and additional questions of design change influences in the area of testing vehicle passability. The first part of the article contents description of partial computation simulation models construction which the calculations are associated with. The binding conditions of calculations are mentioned also. In the second part of the article, there are mentioned and evaluated the results of performed simulation calculations. These calculations are performed in order to find out an influence of operation conditions on the vehicle passability. Real operation condition is invasive vehicle speed into a slope in this case. Under investigation is the change of the gradient angle uphill maximum and beaten distance uphill that is the vehicle able to overcome.

Existing models of predict the abrasive water jet cutting effects, does not give satisfactory results in a wide area of parameter changes, in particular for different, exotic materials. This implies the need to carry out extensive research in order to expand the empirical database. To optimize the process can be used modern methods referred to as Design of Experiment. One of the methods to determine the effect of parameters on the controlled different technological processes is the Taguchi approach. This method allows to limit the amount of research needed to achieve the desired test results, reducing the time required course for their performance and at the same time their costs. Characterized by Taguchi ratio signal / noise (S / N) enables the assessment of the significance of the impact of various parameters on the process, which is still not well enough understood. The article discusses one method for optimization of cutting tool steel, by high pressure abrasive water jet.

The test station is used to determine the fatigue of bearings in passenger cars. The influence of prestressing or axial clerance, the reliability of the locking elements for the axial adjustment, the quality of the seating of the outer ring and the change in the type, quantity or distribution of the lubricant can also be examined. The test station consists of a test unit for the simultaneous testing of two test bearings. The misalignment of the wheel contact point and the center of the bearing is fixed by means of mountable parts. The test bearings are clamped between the flanges at both ends of the test shaft, which is supported by two auxiliary bearings. The numerical simulation with finite element method (FEM) deals with the analysis of the bearing test station, which will be loaded by axial and radial loads.

The principle of vibrodiagnostics lies in the appropriate measuring and analysis of mechanical vibrations of machinery and constructions in industrial and laboratory environment.
The aim of this paper is to perform diagnostic measurements on the most essential parts (spindles) of machinery devices Semico VCM 1000. Measurements were carried out by means of portable vibrodiagnostic measuring device Adash A4900 vibrio M. Vibrodiagnostic itself was realized as a walk-monitoring of machinery state according to corresponding technical standard ISO 10816-3:2009, and of limit values, which took place at regular intervals in the selected organization.

The article deals with additive manufacturing technologies especially with ability to create reports on FDM 3D printers. These assemblies are non-disambiguable. Therefore, it is important to choose the optimal magnitude of the deviation between the walls so that the mechanism has the required mobility. These deviations are examined in several materials with different rheological properties. Finally, the dependence of the magnitude of the variance between the walls and the thickness of the layer for the given materials is shown. The result is the recommendation of modelling and printing parameters.

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.

The development of economy can not be separated from sufficient energy supply. With the progress of technology, the distribution network gradually expands the capacity and transportation, but also brings security risks. The distribution automation system can effectively manage the power grid faults. This paper briefly introduced the calculation model of the economic cost and the reliability rate of the distribution automation, and then the assembly scheme of the distribution terminal was optimized by using the improved binary particle swarm optimization (PSO) algorithm. Next, the simulation analysis of the distribution terminal distribution on a 10KV main feeder line in Xuanwu District of Nanjing city was carried out in MATLAB software. The results showed that the improved binary PSO algorithm could optimize the assembly scheme of remote metering and remote signalling and the assembly scheme of remote metering, remote signalling and remote control rapidly; the hybrid assembly scheme needed a little more time; the power supply reliability rate of the optimized three terminal assembly schemes was over 99%; the hybrid assembly scheme had higher power supply reliability rate and the lowest economic cost.

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.

An important trend today is the continual improvement of product quality with the objective of increased customer satisfaction, but also leading to more effective cost reduction management. Effective quality management in a company also enables increasing production productivity thanks to the increasing amount of top-quality products made and the consequent minimalization of repairs of non-conforming workpieces. This contribution deals with one of the important tools for ensuring quality in the production process using the FMEA (Failure Mode and Effect Analysis) method used in the production of roller bearings for the automobile industry.

In the presented work, static and dynamic properties of two, theoretically identical composite rods were studied. Those two kinds of rod were made of pre-impregnated fibers so called "prepregs". The first of them was made by means of wrapping technology, which is simply just helical layering of one wide tape around a rotating mandrel. The weakness of this method is possible using only for straight parts. That is why a simultaneous deposition of several thinner filaments in a form of tape called winding was used in order to optimize this technology also for curved parts with various cross-sections.
The target of this work was to compile numerical model and experimentally compare flexural strength of the theoretically identical wrapped and wound rods in the static three point test.Further small samples cut and extracted from those rods were subjected to dynamic bending loading on Dynamic Mechanical Analyzer, with various loading speed, in order to obtain also the dynamic properties. The found results and conclusions of this article should provide a basic idea how significantly the manufacturing process could affects the microstructure and real mechanical properties of long fibers composite parts.

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.

Detonation is a specific type of a rapid exothermic reaction, which always involves a detonation wave (in the explosive) and the shock wave (in the environment). Modelling of the pressure wave falls in the fluid flow and interference with obstacles in the flow. The purpose of this paper is to development of simulation model based on the finite element method (FEM) for shock wave propagation in air form the explosion of a spherical charge from TriNitroToluene (TNT) material. The air is the classical ideal gas and explosive material TNT is defined using Jones-Wilkins-Lee (JWL) equation. The computational model is 2D-dimensional model with four node axisymmetric elements. The effect of the explosion on the pressure distribution in the air and rigid surface (ground) is investigated. Numerical solution of the dynamic response was performed using commercial FEM software ADINA.

The usage of aluminium alloys has an increasing trend in the manufacturing industry in recent years. This fact is connected with their ability to combine their very good properties. Characteristics of aluminium are low specific weight, very good thermal and electrical conductivity, and ductility. However, the major disadvantages are low strength and hardness. Therefore the aluminium alloys are alloyed with the elements, which would significantly improve the properties of aluminium. The machining process of aluminium alloys is influenced by many factors that affect the machinability. These factors are for example process conditions, cutting tool material, cutting tool geometry, cutting environment or the chemical composition of the machined material itself and microstructure of the workpiece. Due to the different structures, the machinability of aluminium alloys and pure aluminium is significantly different. Factors such as chemical composition, precipitates, the number and position of soft particles or the strain hardening degree affect the behaviour between the cutting tool and the workpiece during machining. When machining the aluminium alloys, there are some problems such as the surface quality, micro-geometry, tool wear, the chip shape, built-up edge formation, etc. The article deals with the surface defect investigation after the machining process, when on the surface of the material stay the visible "snowflakes" after the turning operation. These "snowflakes" were documented and were performed analysis and observation to find the cause of these flakes.

This study is focused on the effect of pigments on polycarbonate (PC), especially the dimensional stability and flow properties of this material. This polymer is commonly used in the plastics industry and the most common processing of this polymer is injection molding technology. Three different pigments made by Lifocolor company were selected for PC staining. In addition, six different concentrations of aforementioned pigments were used. It is worthwhile to note that the pigments in the polymer matrix acted as a filler. Just like fillers, the pigments also influence the shrinkage of the polymer in both the main and secondary directions. The paper also deals with the effect of pigment concentration on the melt index (MFI). It was shown that the presence of pigments reduces the thermal mobility of the macromolecular chain. Melt flow index changes were also directly tied to the changes of the viscosity, which was also affected by the pigments. It can be expected that the viscosity might not remain the same even at varying shear rates.

This article deals with the experimental grinding of cermet materials. Two types of cermet materials from different suppliers were ground under constant grinding conditions using a diamond grinding wheel. The main aim was to determine the influence of the grinding on the degradation of the grinding wheel and changes in the grinding process. Both types of cermet were ground with the same strategy and the same number of passes. The grinding wheel was analysed during grinding using an optical scanning device to observe the changes on the grinding wheel surface. Clogging and wear of the grinding wheel occurred on the surface as the amount of material removed increased. All grinding tests were carried out without dressing or truing of the grinding wheel. Degradation of the grinding wheel had a big influence on the grinding process in terms of the spindle load during grinding. The roughness of the ground surface was also measured using the optical scanning device. The results from this work will be used for further research of cermet grinding.

This paper deals with the evaluation of the graphite cast iron structure and change of the dynamic behavior dependent on the graphite shape. Structural analysis is focused on the study of cast iron with flake and globular graphite. These two materials have a considerable application in manufacturing due to its specific mechanical and physical properties. The production of gray cast iron is less demanding in terms of the technological process and the quality of the raw materials compared to ductile cast iron but this material is the best for the production of castings. Compared with cast steels are these graphite castings less susceptible to the notch effects of fatigue stress and have a higher value of damping. Internal damping occurs in the structure of the material and can be caused by its imperfection. Computational measurement of eigenshapes and eigenfrequencies was performed using modal analysis in the SolidWorks software environment.

This article deals with the influence of grinding conditions and tilting the spindle on changes in the spindle load when grinding tool steel on a 5-axis tool grinding machine. The experiment was designed to investigate any changes in cutting speed, feed rate or tilting of the spindle. The size of the load is very important, because the load can influence the tool life, the life of the machine components, quality of the surfaces and dimensional accuracy of the components. A medical femoral knee replacement was selected as the semi-finished component for the experiment, as its surface is a good representative of a complex-shaped surface. This article is limited only to the grinding of maraging steel MS1 with a CBN grinding wheel. The second part of this article is focused on the experiment where the spindle load is evaluated and the results of the experiments are compared.

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 aim of the work was to evaluate the whole system of the springs of a passenger car. The influence of inflation and the type of tires on the acceleration of the various parts of the car (axle, steering wheel, driver's seat attachment, body shell and acceleration affecting the driver) was investigated. The types of shock absorbers and springs of the passenger car were also examined. The sensors used acceleration and pressure sensors between the wheel and the road using test stands. The benefits and reserves of the individual systems were compared, and in the systems with the cushioning rigidity, all the suspension setups were evaluated. The work was done experimentally in laboratory environment as well as in real operation.

Dynamic load of the improved hatch cover construction for universal open-box type wagon is researched, taking in to account the worse loading scheme - impact of 150 kg cargo from height of 3000 mm. In the case of improved hatch cover construction, dynamic load character reduction up to 50% can be reached, compare to conventional one. Hatch cover model of proposed construction for strength calculation was created. Strength calculation is done by finite-elements method in Cosmos Works software. Calculation of hatch cower durability, considering symmetrical and asymmetrical load cycle are carried out. In the proposed construction, areas with maximum equivalent stresses caused by usual operational load are defined. Results of conducted research can be useful for projection of new wagon generation with improved technical, economical and operational parameters.

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.

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.

This paper will investigate the changes in size and amount of the microstructural features in secondary aluminium casts associated with different wall thickness. The experimental samples were casting into the sand mould. The changes were documented and assessment by using optical microscope and methods of quantitative analysis. The results shows that increasing wall thicknes lead to formation larger second phases and coarsening of the matrix, which lead to decreasing mechanical properties.