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This paper is focused on occupational health and safety hazards in machining processes. Problem is specified on employs and employers. Occupational health and safety is based on legislative regulations. Safety rules are usually formulated generally. But it is necessary to formulate safety rules more precisely for different production processes and even for different production machines. And this has not been fully satisfactory solved, especially from the point of view of the development of machine tools, their automation and also from the viewpoint of the development of cutting materials. In the paper principal occupational health and safety hazard in machining will be formulated on the base of laws, regulations and personal findings of the paper's authors in different enterprises. As an example safety hazards and safety rules will be in depth formulated for turning. Similar health and safety rules and hazards must be formulated for other cutting processes. But occupational health and safety problems relate not only to persons but also to enterprise economy.

The paper deals with a construction design of a versatile adaptive gripper for a robot manipulator. More specifically, it presents construction design of motional kinematics of fingers, which are controlled by a working screw, and also computation of forces and a selection of drive actuating units. Calculation of forces is needed for further correct selection of an engine transmission, considered gearing, belt gear and transmission.
Automation is a process of replacing man's control function by operation of various machines and devices. Automation is a highly complex process including very simple control operations, which are performed automatically by relatively simple devices, as well as very complex control of large production units. Control is a purposeful action of evaluation and processing of information about the controlled object or process, actions in the process (these may include measurement device data, signalling equipment states), and according to them, related machines are controlled so that the prescribed objective can be met - handling piece loads of maximal weight m = 25 kg in this instance.

The contribution is dedicated to surface integrity assessment of components from the point of view of residual stress profile after machining and finishing technologies. Residual stresses play the key role for dynamic life and service reliability of the part, especially rotating aircraft airfoils made of titanium and nickel base alloys. Except a brief summary of measurement methods practical experience with application of Beam deflection method combined with electrolytic etching is published. Specific measurement results for real aircraft Ti6Al4V airfoils and Ti6Al4V plates following its manufacturing technology are the subject of experimental part.

This article describes usage of ultrasonic method TOFD for testing of welds on plastic pipelines welded with butt fusion with hot plate. As an artificial defects were selected cold fusion and inclusion in the weld area, by using metallic tape and wire as a mentioned defects. To test defects was necessary to use wedges with water as a bonding agent. Results of testing are proof of usefulness of this method. It can severely reduce risks of accidents caused by unidentified defects, which can occur in welded joints. Since plastic pipelines are used even in nuclear industry as a replacement for metal pipelines for its resistance against radiaton decay, it is necessary to implement similar testing regulations to avoid fatal incidents and method like TOFD and Phased Array ultrasonic testing can prevent such failures.

The goal of this contribution was to describe the microstructure and properties changes of difficult to cut materials after turning. Surface residual stresses, roughness, microstructure of AISI 304 type stainless steel were studied as a function of side rake angle o. Residual stresses and phase composition of surface and sub-surface layers were determined using X-ray diffraction techniques. The presence of strain-induced martensite was investigated using Barkhausen noise, optical microscope, and microhardness measurement.

In order to ensure acceptable level of risk associated with exposure to airborne dust they should have been mainly technical and organisation measures at workplaces with enhanced occurance of dust. Local exhaust ventilation (LEV) belongs to principal engineering control for prevention of airborne spreading. The aim of the study was to assess the efficiency of LEV system used at mechanical workshop for controlling respirable fraction of dust during stainless steel grinding activities. Dust control effectiveness was assessed by determining personal exposure levels with and without the use of LEV system. Personal dust samples were collected using a photometer-type dust monitor. On the basis of results it can be concluded that LEV system significantly improved quality of workplace atmosphere at given workplace.

Residual stresses significantly affect the life of parts material, especially in bearing manufacturing, where the stress introduced into the material in the manufacturing process affect the component throughout its whole operating life. It is therefore important to know the size and orientation of these stresses and to optimize the production process of the bearing rings, in order to eliminate as many of these undesirable stresses. The subject of the article is chosen at demand of practice and has to correlate coating cutting tool for residual stress and microstructure in turning the outer bearing rings made of material 1.3520, which is widely used in bearing production. Turning cutting tool WNMG 080408E-M was used with two different coatings. We conducted measurements on a X-ray diffractometer. We measured normal stress parameter and the FWHM (full width half maximum at), which is decisive, and it is related to the grain size of the material. We found that the residual axial stress approaching the zero value, depending on the etched layer.

Modification alloy is an important part of the metallurgical process, and this also applies, of course, for aluminum alloys, particularly for Al-Si (silumins). As a modification of the material we can use the modification using the selected element or heat treatment of alloys, or a combination of both processes. One of the elements that it is possible to modify the alloy of Al-Si used is antimony (Sb). The paper examines the possible effect of the modification that element and heat treatment on the final tool wear after machining of the alloy AlSi9CuMnNi. In the experiments were made three castings from the alloy AlSi9CuMnNi without modification, three castings with the modification and without heat treatment, three castings with modification and without heat treatment, and three castings with modification and heat treatment too. These all castings were machining by turning with the same cutting conditions and next the tool wear of using inserts was analyzed. The described experiments and analysis are part of extensive research, focusing on a Faculty of Production Technology and Management, J. E. Purkyne University in Usti nad Labem.

The article deals with contactless thermal forming of metals. In the introduction the bending theory of components by using flame technology is described. On the basics of information obtained from the analysis of previous research a technological procedure was developed. This technology uses gained characteristics of material behavior in the process of heterogeneous circumferential heating. The principal of material concentrating in the process of local heating the area which is placed in a quasi prism leads to a bending moment. This bending moment evokes deformation of the material which was compacted this way. Application of subscribed technology pushes the limits of forming to a higher level because by using conventional forming processes the trajectory of the component is not straight but curved. Because of this phenomenon it would be necessary to apply forming tools which dynamically change and do not still exist.

Comparing with one directional magnetic treatment, a multidirectional magnetic treatment is applied to reduce residual stress in thin-walled bearing rings in order to improve the dimensional stability of bearing rings. The magnetic field was applied in both the axial and the radial directions of the thin walled bearing rings respectively. Six months of repeated testing results demonstrated that the dimension of bearing rings after magnetic treatment had no significant change. Experimental results shows both the major axis(the longer axis of an ellipse)and the minor axis(the shorter axis of an ellipse)appear shorten tendency and the dimension of bearing rings tends to be stable. Thin-walled uniform radial pressure deformation formulas are applied to calculate the reduced stress, and the maximum reduction is up to 45.97MPa. Research shows the multi-directional magnetic treatment can improve the dimensional stability of bearing rings and used in practical engineering.

Mechanical vibration is undesirable in the majority of cases. It can have a negative influence on accuracy of manufacture, service life of processing equipment and tools, labour protection, human health and so on. Excessive noise belongs to the accompanying phenomena of the mechanical vibration too. For these reasons it is necessary to eliminate mechanical vibration in an appropriate manner. There are different possibilities of vibration damping. Application of suitable materials with damping effects belongs to these possibilities. This paper is focused on structural damping of materials. Damping properties of different materials were experimentally measured and subsequently evaluated by means of the forced oscillation method. It was found that the vibration damping depends not only on the material type but also on material density and thickness, excitation frequency and mass load.

The paper deals with a study of actuator (brake cylinder) modification for generation of braking force in a brake unit. The original solution, carried out using the original brake cylinder in cooperation with the proportional pressure control valve, is sufficient in terms of correct function of the brake unit, but in terms of safety, the corresponding force sensor may be damaged in case of a control circuit proportional pressure valves defect. Another reason for the study is utilization of the total regulation range of the proportional pressure valve and improvement of the brake unit response time in case of braking force overload. Such overload results in tread or rotating rail surface damage. The article gives description of the currently implemented passive measures to increase safety against sensors damage, but also of proposed active measures to eliminate these defects by changing size and type of the brake cylinder.

Degradation of technical objects is a natural phenomenon, but for users of these objects brings many problems. These problems are manifested by shortening lifetime, lowering safety and increasing costs for the technical operation of technical objects. This article analyzes the causes of degradation of parts steam generator using methods of microscopy. Degradation processes that occur most frequently in parts of steam generators are creep, corrosion and wear. The degradation occurred on the tube of convection superheater from steel CSN 41 5128. It was found that the inner surface was covered with corrosion products and was disrupted its cohesion. For search of the causes of degradation were used spectral analysis, microscopic analysis and determination of the weight of oxide layers according to CSN ISO 8407. Based on the results of analyzes, it was found that the occurrence of degradation is related both microstructure of pipes which did not comply with the required state and also with non-standard environment, which was exposed the inner pipe surface.

The objective of this work was to investigate and evaluate the effect of the composition and production on microstructure and tribological properties of cobalt alloys. The referece material was Co-28Cr-6Mo alloy, which is successfully used in the medicine for many years. The excellent corrosion resistance is the advantage, as well as better wear resistance than is offered by titanium or stainless steel implants. Standard Co-Cr-Mo alloy and also Co-Cr-Mo alloy with Ti in an amount 5 wt. %, were prepared by casting and also mechanical alloying followed by "Spark Plasma Sintering" consolidation. The influence of production route as well as influence of alloying elements on the microstructure and tribological properties was observed. Based on the obtained results, the Co-Cr-Mo-Ti alloy produced by casting seems to be most suitable, because the addition of titanium has greatly improved the wear resistance.

Self-hardening secondary Al-Zn-Si-Mg alloys represent an innovative class of light Al-Si alloys. The most important and relevant feature of the self-hardening alloys is related to their good performance, without the need of any heat treatment. Mechanical properties depend upon the morphologies, type and distribution of the phases. It is therefore important to study the intermetallic phases occurring in the secondary Al-alloys, where they found more than in the primary-Al alloys. Study of intermetallic phases in the alloy was performed on an optical microscope using classical etching technique (by 0.5 % HF) to invocation black-white contrast as well as unconventional methods for invocation colour contrast (etching by Weck-Al) to the observed surface of the sample. The colour metallography results were correlated with the information obtained by standard etching. The microstructures of the samples were analysed by scanning electron microscopy after standard etching and deep etching (with HCl) too. After deep etching we are able to see the 3D morphology of eutectic Si particles and intermetallic phases.

To design an optimal support of a large shade sail it is necessary to determine forces in wire ropes that support the sail. Relations between a sail loading and ropes reaction forces, rope diameters and sail stresses were investigated. To simulate the sail behavior and set up these relations, numerical (FEM) models were created and analyzed. Most of the results show nonlinear relations between above mentioned parameters and they depend on the sail geometry, applied loads and the rope diameter. It means that for every specific geometry and loading of particular sail an optimal rope diameter and support should be designed. The nonlinear numerical analysis is very suitable tool for this purpose and thus specialized systems based on the Finite Element Method (FEM) should be used to simulate and analyze such problems.

The situation of analysis and finding solution of unique material flow managing and planning in production company allows increasing the competitiveness company on the market. The uniqueness of the material flows is in its combination of metallurgical and machinery character. There are continuous metallurgical and discrete mechanical material flow with even different speed which are joining at one place - aluminium casting. The research has brought also the recommendation of new layout of the company. Each company is original from the point of production processes. Application of standard enterprise information system (SAP, proAlpha, Baan, etc.) need difficult adaptation especially for conditions of small or medium enterprises and the price of that system is relatively high. Therefore, the proposed model of capacity planning is much more suitable for the conditions, requires and demands of this enterprisers.

Extrusion process parameters play key roles in aluminum profile extrusion processes. In this literature, by using Box-Behnken experimental design to arrange the simulations using the ALE software HypereXtrude, Response Surface Methodology (RSM) were applied to study the simulation results and discuss the effects of five process parameters, namely billet diameter, billet preheat temperature, die temperature, container temperature, and ram speed, on the outlet velocity distribution uniformity of the profile named an Upper beam on the Train. The interactions between the five parameters also were investigated. Additionally, a second order response surface model between the extrusion process parameters and the evaluation criterion of outlet velocity uniformity was established. An optimization of the process parameters with the purpose to find the most uniform outlet velocity distribution was carried out based on the response surface model. The results show that the three parameters, namely billet diameter, ram speed and die temperature, have significant impact on the outlet velocity uniformity. And there are obvious interactions between these three parameters. After the subsequent optimizations, a more uniform outlet velocity distribution was obtained, and the final acceptable profiles were produced.

The presented article describes and characterizes laser cutting of PMMA, the impact of the laser beam on the PMMA material and compares it with a conventionally using cutting of plastic material - milling. In the experimental part is compare sample shown in Fig. 4 which was cutting by using a laser beam, milling and the sample which has been cut by laser but was modified by drying, which change properties of the material after cutting.

This paper deals with the possibility of spent portable batteries treatment with the aim of zinc recovery. Perspective of pyrometallurgical and hydrometallurgical process is described. Samples of zinc based portable batteries were submitted under the investigation. Aim of the work was to find the best conditions for zinc recovery. Experimental work focused on hydrometallurgical process was conducted. Results have shown 100 % zinc recovery under these conditions: leaching in medium 2 M (NH4)2CO3, addition of 20 ml of NH4OH as reductant, leaching temperature 20°C, within 10 minutes.

The present contribution represents the analysis and optimizing management of the measurement system of the technological process of pressing. It has been chosen the combination of appropriate methods for achieving the objective to minimize the cost of quality assurance of the measurement process by means its management. The quality of the measurement process has been verified by the reference standard (etalon). The optimization of evaluation measurement has been searched by utilizing QFD method (Quality Function Deployment). The subsequent optimization has been implemented by the taking into account the results of the use of the control charts and the deployment of QFD method and Kalman filter.

The article deals with the measurement on CMMs with tactile stylus system. Accuracy of CMM is mostly indicated by the parameter MPEE (Maximum Permissible Error for length measurement). This parameter refers to an errors during the measurement of distance between two points in space. Verification of MPEEparameter is described in an ISO standard 10 360-2 Acceptance and re-verication tests for coordinate measuring machines. These acceptance and re-verification tests are often conducted with a short and stiff reference stylus which is not and also mostly cannot be used in real measurements. On the contraryin applications such as a measurement of engine blocks and transmission housings very complex styli configurations are used. The influence of stylus system configuration on the variability of measurement when using long extensions, different materials (aluminium, carbon fiber composites) and high scanning speed in not described. The aim of this article is to design a methodology for testing the styli systems used in complex metrology applications in quality control of hi-precision mechanical components, to analyze the contribution of stylus system configuration to the measurement system variability in the form of a standard measurement uncertainty described by standard deviation.

This paper was based on the cooperation the Department of Machining, Assembly and Engineering Metrology with company accredited by Czech Institute for Accreditation. It deals with issues of calibration 3D indicators. Generally, the calibration of non-specified working gauges integral part of every company, which uses such gauges. Checking/calibration of measuring instruments is important for ensuring the uniformity and accuracy of measurements to ensure continuity of measurement results. The paper deals with streamlining the process of calibration of indicators 3D design and practical verification of appropriate gauge for the calibration. The target of innovation is to eliminate the errors and shortcomings of the current solutions. In the conclusion are the results of calibration by help current and new solution checking device and their comparison.

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.

An analysis of the friction time influence on creation and structure of the mixing zone during the friction welding process of the two dissimilar steels is presented in this paper. The changes were monitored on the two welded samples, made of the highly-alloyed steel HS 6-5-2-5 and the high carbon C60 steel. The objective of this work was to show how the mixing zone is created and to point to its influence on the quality of the whole welded joint, since it is characterized by the inhomogeneity of the microstructure and the chemical composition. Those problems arise due to the thermal and deformation conditions, so during the experiment the welding pressure (70-90 MPa) and the welding time (3-18 s) variations were monitored. Experimental results have shown that the shape and the structure of the friction zone are strongly dependent on the friction time and that by its variation one can obtain the desired structure and thus the quality of the friction welded joint. Based on obtained results the minimum value for the friction time is recommended.

This article is focused on influence of finishing operations on the surface quality of polymer products. Finishing operations are the necessary part in the production of injection mold cavities. Surface quality of cavities is reflected to quality of future polymer products. Therefore, it is very important to use appropriate finishing operations and its technological conditions from the aesthetic point of view. However, it is not always necessary to use time consuming and most expensive finishing operations, because the polymeric products are not able to achieve similar surface quality as cavities. The different surface quality of injection molded parts can be also expected using various supramolecular structure of polymer (amorphous, semicrystalline). Supramolecular structure of polymer determines the future properties of product as well as the distribution of the individual macromolecules in the polymer chain. Divergent distribution may result to achievement of different surface quality of injection molded parts. This research is focused on finding an influence of supramolecular structure of chosen polymer on the surface quality of polymer product.

The article deals with the internal defects identification and characterization in butt weld joints by non-destructive ultrasonic Phased Array and X-ray technique. Basics of ultrasonic and X-ray testing are described in the theoretical part of manuscript. Phased Array and X-ray technique are volume nondestructive methods that can detect internal defects without breaking of construction. Ultrasonic Phased array and X-ray test procedures and test results obtained in non-destructive testing of butt weld are shown in experimental part. Ultrasonic record, X-ray record and weld macrostructure are given for each identified weld deffect. Advantages and disadvantages as well as comparison of ultrasonic and X-ray testing resulting from experimental measurements are described in the end of this article.

Using of cutting inserts is currently a normal part of the manufacturing process. The article deals with structural analysis and material selection of inserts for turning. Analysis of the composition of experimental inserts was made by electron microscopy, namely EDS analysis. EDS analysis is an analysis using an energy dispersive spectrometer. For this purpose was used EDS analyzer Bruker 16 which is part of a scanning electron microscope Tescan Vega 3. These analysis can provide a good picture of the structure and construction of inserts and their composition. This may assist in finding suitable cutting conditions. These analyzes were performed in other experiments performed at the Faculty of Production Technology and Management at Jan Evangelista Purkyně University in Ústí nad Labem.

In this work, the influence of alloying elements on the transformation temperatures and temperatures of formation of NiTi intermetallic phases were investigated. NiTi alloys are characterized by shape memory effect, pseudoplasticity and superelasticity. These properties strongly depend on the alloy composition in binary Ni-Ti and ternary Ni-Ti-X. Because these alloys are used in various branches of industry, such as aerospace, engineering or medicine, the addition of ternary element can influence their application significantly. Especially, the presence of Ti2Ni and Ni3Ti in the NiTi matrix may cause a degradation of the shape memory behaviour and mechanical properties. For this reason, we observed the formation of intermetallics by differential thermal analysis (DTA). Differential scanning calorimetry (DSC) experiments were performed to monitor the evolution of the transformation characteristics. We report new results, which show the strong dependence of the transformation temperatures between austenite and martensite on the alloy composition, and how the alloying elements (Mg, C, Zr) influence the formation of Ni-Ti phases.

An important characteristic of industrial robots is their accuracy. It is of particularly importance in high-precision tasks, e.g. mounting or machining of elements. In order to meet the requested quality demands for products, as well as appropriate working conditions, it is absolutely essential to regularly inspect the technical condition of robots, e.g. their accuracy.The following paper aims at identification of accuracy errors of an industrial robot MOTOMAN HP20. The selected measuring method was the roundness test with the use of the telescopic, kinematic QC20W - Ballbar. The paper presents the methodology of experimental tests. The influence of the radius of the interpolation circle, as well as the influence of the set motion speed on the value of chosen accuracy errors was determined. The results were presented graphically and analysed.