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This paper deals with the comparison of two tool steels M390 and M398 produced by powder metallurgy of the MICROCLEAN type. The primary use of steel is in the plastics industry to produce screws for injection moulding machines. The main purpose of the paper is to analyze the hardness after different stages of heat treatment. The first part of the article evaluates the hardness of steels after hardening, which was performed using a hardening dilatometer DIL805A. A total of 8 different controlled cooling measurements were performed, for both types of powdered tool steels, from a maximum rate of 100 °C/s to a minimum of 0.01 ° C/s. Based on the results of the first set of samples from the hardening dilatometer, the optimal cooling time is evaluated to achieve the highest hardness of both materials. This rate was used to heat treat a second set of samples that had undergone a quenching process from which a selected group was quenched to -78 °C. Freezing was performed to reduce the amount of residual austenite. Before measuring the hardness, the samples were tempered at temperatures of 200, 400, 600 °C for 2x2h. The measured hardness values were then compared with data from the manufacturer BÖHLER.

This work discussed the corrosion behavior of the internal surface of pipeline steel caused by the composition of petroleum products, particularly crude oil. Internal and external pipeline corrosion is the notable cause of pipeline failure in Malaysia’s oil and gas industry. However, internal corrosion is preferred to be concerned in this work because it involved one of the major corrosive media in the crude oil, such as sulfur content. This project aim is to find the sulfur concentration in the crude oil using Fourier transform infrared spectroscopy and atomic absorption spectroscopy. The corrosion rate, corrosion current and corrosion potential of the API 5L X65 grade carbon steel pipeline in different simulated H2SO4 solution concentrations were carried out using the Tafel extrapolation technique. The corrosion properties of the samples were morphologically measured by means of optical microscope, scanning electron microscope and energy dispersive X-ray analyses. The results showed that the corrosion rate of the pipeline steel significantly increased with the increasing H2SO4 concentrations. The corrosion products formed on the pipeline steel surfaces were mainly composed of iron sulfate, iron sulfide and iron oxide. These findings are crucial to understanding the corrosion behavior caused by the crude oil and should be further investigate with the other possible influence factors such as temperature and petroleum’s flowing velocity.

The present contribution examines the structures of and corrosion processes in copper-basalt composite laser claddings on a steel substrate. The cladding material was a laboratory mixture of the following components: Oerlikon METCO 55 (Cu > 99.9 %) + basalt dust. In this investigation, metallographic structures of copper-basalt composite laser claddings were studied using optical and scanning electron microscopy. The adhesion of the claddings to the substrate was testing using the non-standardized Mercedes test. A potentiodynamic corrosion test in artificial mine water was performed on a specimen of the composite laser cladding. The test results were compared against those for a reference high-purity copper standard and AISI 304 steel. The findings were interpreted in terms of the potential of using copper-basalt composite laser claddings as corrosion protection coatings on steel components in nuclear power generation.

The aim of this paper is an analysis of the dependability of critical components of the John Deer 7530 tractor. For this analysis data was used from a database which contains maintenance data of 166 trac-tors during approx 9 years. The first part of this article is devoted to the selection of critical compo-nents based on number of failures of individual machine parts for a given period and their sales pric-es. The next part of article presents data for calculation dependability indicators which contains oper-ating times to failure and operating times without failure. Due to the large size of the data files of the individual components, the data are only given for one machine component. Furthermore, the meth-od of calculation of dependability indicators is described by parametric statistical methods according to ČSN EN 61649:2009 and mean time to operating failure. The results of the analysis are summa-rized in tables and graphs. The method in this article can be used to optimise the maintenance pro-gram.

The features of quality, which is an ambiguous, gradual and very subjective concept, cause that there is no one absolute standard for it. Scientists are looking for ways of its evaluation and improvements of the existing methods. It relates to various areas, but at the same time it is also complex and multi-faceted. There are so many definitions of quality that are constantly evolving. In the paper two meth-ods Servqual and Servperf to assess the quality of teaching services were used. The aim of the paper was to compare the results of the service quality analysis with use of both methods and to indicate the differences between them. It was also checked whether conclusions regarding the quality of ser-vices differ depending on the used research method. The Servqual method takes into account the individual expectations of the respondents, which may affect the assessment of the actual service. It is more complicated, but the results are more adequate to the specifics of the service. It was shown that in one of the areas the results concerning the quality of teaching services differed significantly depending on the used method. However, it is not yet clear which of the two scales is a better meas-ure of service quality.

The presented paper deals with the design of a knee simulator that uses pin-on-ball configuration, ie cartilage and CoCrMo head. The translational motion consists of the cartilage and the rotating head when the load of the articulating pair is derived. The simulator meets the predetermined kinematic conditions according to the ISO 14243-3 standard, including dynamic loading. The simulator is able to record the coefficient of friction during the test, which helps to understand the biotribological processes in the knee. The structural part of the simulator is preceded by a research part, in which the existing simulators and tribometers, which helped to create this design, are analyzed. In the experimental part, specific elements (drives, sensors, etc.) are selected that meet the defined boundary conditions, and the method of friction measurement is determined. The paper concludes with an overall evaluation of the proposed knee joint simulator, which will be able to achieve the conditions according to ISO 14243-3 and at the same time record the course of the coefficient of friction between the cartilage surface and the CoCrMo head.

The atomic force microscopy is method used to obtain surface properties of various materials, includ-ing surface morphology, local magnetization, conductivity and mechanical properties. In this work the atomic force microscope was used to investigate properties of rubber compounds. Three samples made of different rubber compounds that varied in filler content were studied in order to determinate their homogeneity and ratios of their Young’s moduli. Images of their surface topography were ob-tained and then on each sample five places were chosen where spectroscopic curves representing force – distance dependence were scanned. Parts of these curves from which Young’s modulus can be determined were approximated by linear functions and their slope was calculated. Slope values close to each other suggest similar values of Young’s modulus. By their comparison it was determined whether even distribution of ingredients in rubber compound can be assumed and thus the blending process to produce these compounds can be considered sufficient.

When electrical energy is drawn by electric vehicles from charging stations at charging process the voltage drops and increased current loading of cable lines in distribution grid occur. Inasmuch the electrical grid is insufficiently dimensioned or at large amount electric vehicles concurrently charges without controlled charging system, the voltages could decrease under desired level in grid points. This leads to the deterioration of voltage quality in given grid. The higher cables current loading leads to active power losses increase and decrease their service life. The paper describes the utilisation of modelling the electric vehicles when charging by power load model in physical diagram implemented into alternative simulation software. The created charging station load model is used for solving of voltage studies in distribution grid and for the analysis of cable lines ampacity. The grid contains a small number of points and low penetration of charging stations. Voltage levels are solved when random operation of charging stations during the working day without controlled system. For other loads, the typified daily loads diagrams of households are used.

In this paper, innovative resistance element welding (REW) technology for joining galvanized steel sheets to thermoplastics (PMMA) is introduced. The essence of the innovation is in the use of a special bimetallic joining element consisting of the core made of a Sn60Pb solder, and the sleeve made of a Cu tube. During resistance heating, the solder melts, thus allowing the formation of a metallurgical joint with galvanized steel sheet. Since Sn60Pb solder melting occurs at temperatures (from 183 to 190 °C) be-low the thermal decomposition temperature of most thermoplastics (for PMMA above 300 °C), there is no thermal destruction of the PMMA material around the joint. The mechanical fixation of the thermo-plastic material at the overlap joint is provided by the sleeve made of Cu tube which has a substantially higher strength than a Sn60Pb solder.

This paper investigates the replacement of a conventional steel coil spring with a composite disc spring with the aim of minimizing its weight. Simulation in the CAD system Siemens NX 12 was used to determine the composite disc spring’s behavior. The regression functions were stated based on the numerical simulation. Based on the regression functions the solution with the minimum weight was found using software programmed in Matlab. The prototype discs were manufactured from carbon fibre prepreg. Their load-deflection characteristics were tested and compared with the designed values. The experimental results show that using this solution reduces the weight by about 30% in this case.

CFRP (Carbon Fiber Reinforced Polymers) are often used when designing parts that need to be stiff, light and thermally stable. These benefits are a big motivation to use CFRP in many applications, one of them could be sports optics. However, optical devices require precise dimensions with tight tolerances for the opti-cal assembly to work correctly. In order to determine if CFRP could be a suitable material of choice for sports optics a simplified body of binoculars was designed. The main purpose of this prototype was to prove the possibility of using CFRP in binoculars. The tubular body was manufactured by prepreg lay-up into a 3D printed mold, followed by curing in an autoclave. After the prototype was manufactured 3D measurements of the tube using 3D scanner GOM ATOS were made. As expected, shrinkage of the mold and the epoxy resin in the matrix of CFRP caused minor deformations. However, if the shape of the cured part remains unchanged during conditions similar to the general use of binoculars, then the initial deformations happening during manufacturing could be accoun-ted for when designing the part. Other than the carbon part itself, the bond between metal and composite components is another potential point of failure in terms of desired precision. Because of that measurements and tests of concentricity of ad-hesive joints are being currently performed. The results of these tests and others that will follow will indicate if composite materials could be used as a structural material for sports optics.

A number of asset management models, methodologies and tools are available and well known today. How-ever, various organizational approaches to asset management processes are adopted by companies in the industry. In the paper, a number of examples of maintenance process models are summarized and a comparison of examples (benchmark) of real maintenance organizational structures is presented. The used examples origin from chemical, petrochemical and automotive industries. On this background, a case study of major maintenance organization change in Unipetrol, a central European refinery and petrochemical group (part of PKN Orlen) is presented and analysed. The goal of the implemented changes in the company was to increase the overall efficiency of the maintenance organization, mainly in the areas of management, and to achieve the set KPIs. Organizational changes were implemented on the basis of a model of a close connection between maintenance and production organizations in the form of a Multi-profession production team, named “Facility team”. The changes in the organisational structure and asset management processes described in the paper had finally a significant impact on the number of management positions (reduction by 25%), roles, competencies and asset management process flow. The quantitative impacts to KPIs in areas fulfilment of process safety requirements and efficiency, after implementation this changes, it had a positive effect in the horizon of the coming year and are also evaluated and analyzed in the paper.

Optimization is the process of finding the best possible solutions of a problem. It has been widely used in various areas especially in engineering problems. One of the common issues that is faced by some of manufacturers is finding drilling sequences of multiple holes. By drilling multiple holes with the least total path length, the manufacturer can save a lot of time and it can increase the productivity of the company. Thus, this study focuses on drilling path of multiple holes problem which has been solved by other researchers. This study uses the Bees Algorithm to find the best sequence of drilling holes (mini-mum total path length) and the results found are compared with the result of other algorithms. In addi-tion to results comparison with other algorithms, the results obtained are verified with simulation results using MasterCAM software. The results comparison shows that the Bees Algorithm achieved compara-ble performance compared to other algorithms.

Very dynamic development in the field of computerization and industry robotization, as well as an im-plementation of the Industry 4.0 assumptions are the main reason for the increased demand for magnetic materials. The limited rare earths availability and the sustainable development in the field of material engineering indicate that the methods of recycling magnetic materials from Waste of Electrical and Electronic Equipment are necessary. This paper presents the impovement stages of magnets recovery process - extrusion process of magnetic scraps/particles with polymer (magnetic scraps and particles obtained from WEEE). The process is developed based on the Process Failure Mode and Effects Analy-sis. The reserch pointed the irregularities, that pose the greatest risk of failure in the process. The paper presents changes in the process based on the values of the indicators: severity (S), probability of occur-rence (O), probability of detection (D) and the Risk Performance Number (RPN). Based on the PFMEA, 5 operations were added to the process. Due to changes in the process course, it is possible to minimize the effects of the irregularities occurrence.

The topic of the article is to compare the mechanical properties and define the differences in the degra-dation process for anticorrosive glass fibres type AR and for glass fibres type E after influence of the alkaline environment in the geopolymer composite. The ongoing reactions between glass fibres and al-kaline environment lead to the dissolution and slowly decomposition of the fibres and consequently to the loss of the mechanical properties of the composite. Corrosion of glass fibres is characterized by weight loss, change of fibre diameter, reduction of mechanical properties and formation of mineral in-crustations on the surface of the fibre, which gradually leads to the formation of a continuous corrosion coating so called corrosion shell. Scanning electron microscopy was used to monitor the morphology of the fiber surface, and image analysis methods were used to evaluate morphological changes. Tests of mechanical properties (fibers - tensile test, composite materials - three-point bending and Charpy test) were used to confirm ongoing degradation processes due to the long-term influence of the alkaline envi-ronment on both types of glass fibers.

This paper deals with the topographic evaluation of samples made from materials applied in biomedicine. Different samples were made from Ti, TiAlV, TiNb and austenitic steel – Fe were used together with different surface morphology created. These samples were coated with a layer of TiNb alloy. The goal was to measure surface roughness in individual samples of biomaterials and to evaluate a 3D measurement of surface morphology made with a confocal microscope. Another task was to compare with appropriate software the pictures of material topography acquired at lower and higher magnification. Lower (10x) and higher (200x) magnification was used. For measured data evaluation SPIP and Gwyddion software were used. The same method of surface treatment was used but on different samples, which can lead to different results. The values obtained from topography measurements are crucial, but their formulation or evaluation can be affected by different processing methods. Our interest was to find and record the theoretically best procedure for the evaluation of measured data. Then to better understand the cell adhesion and integration of bacteria, we dealt with visualization of topography of given samples.

In the last decades, advanced brake technology in the port sector follows the global productivity developments of the international maritime trade. Container vessels are getting bigger and bigger and the ship to shore cranes is getting consistently higher. But service, emergency or storm brakes cannot be getting bigger and bigger to meet these increasing demands. Throughout history, innovations and advancements in technology have made industry better through automation and increased efficiency. No matter how advanced industry becomes, the need for emergency duty stopping brakes will not go out of style because there are always circumstances that require mechanical brakes to do the job. Brakes will invariably insure against those rare, yet potentially catastrophic events that even modern technology cannot defend against.

The article deals with the evaluation of interactions between abrasive particles and treated sample surfaces. It represents a summary of the knowledge gained from research the wear of tools for crushing unwanted growths. Samples of materials were tested under laboratory conditions. The hardness of HRC and HV10 was evaluated in the experiment, abrasive wear rate, assessed according to standard GOST 23.208-79. The depth of the track under test disc by using silicon abrasive particles was also evaluated. Furthermore, the hardness coefficient KT relative to the base material of the tool - 16MnCr5 steel and the hardness of abrasive were determined. By comparing the measured and calculated values the heat treatment procedures and hardfacing materials were assessment. By comparing the measured and calculated values the heat treatment procedures and hardfacing materials were as-sessment, which are expected to provide an increase the abrasion resistance towards to an abrasive, heterogeneous working environment in operation.

The article presents partial results of research to increase the service life of snow ploughshares, which are used for winter maintenance of forest transport roads. The main working tool of vehicles - snow plough is the arrow ploughshare. It is made as a weldment. The contact tool, when in contact with the road, is the rake blade, which is subject to abrasive wear. The experiment consisted of analysing the current state of materials, designing and exploring such options that would ensure a longer ser-vice life of the blades. Welding material was designed to be applied to the base material of the blade. Furthermore, the HARDOX 450 was designed for the production of the whole ploughshare. The last design was welding HARDOX 450 with an electrode OK 48.00 with the base material steel 11 484. This proposal is presented in more detail in the article. The hardness of HBW, HV and HRC was measured on the samples and microscopic analysis was performed using light and electron microsco-py. The aim was to determine the quality of the connection of materials, mixing in the connection zone and comparison with the condition on the original blade. It is assumed that a suitable choice of welding electrode or a suitable choice of abrasion-resistant steel can achieve an effective increase in the life of the snow plougshare, whether from a technical or economic point of view.

Trusses are commonly used structure in industrial buildings, warehouses, bridges, transmission tower etc. The analysis of the truss structure design is necessary in order to ensure stable and economical system. This paper presents application for computing planar truss structures that was programmed in environment of MATLAB App Designer using finite element method (FEM). App Designer is programming environment used for creating computing applications with graphical user interface (GUI). The created application for trusses allows users to create geometrical model of the truss structure and input material data, perform static analysis, modal analysis and to optimize truss structure in order to minimize its weight. To ensure accuracy of results, test calculations was performed using commercial software and compared with results from the created application.

Generative design is one of the most promising means of new product development in the world. It allows formation of organic structures that brings various benefits, e.g. in the form of savings of material and production costs. Generative design includes several types of technology, topological optimization included. The paper addresses the technology of topological optimization implemented on the support part of the 3D printing pad. The result of optimization is the creation of a new, more suitable design concept through the Altair Inspire optimization software.

This article deals with optimization of the truss structure. A genetic algorithm is used for this optimization. Within the strength calculation of the truss structure a normative assessment of the beam and their buckling stability is implemented. Also, the entire calculation is designed to use only standard profiles. In the first task, the optimization is focused on the weight of the structure, and in the second, on its price. There are also developments using different population sizes for individual cases, which will be described below. At the end of the work, a hypothesis is made for the link between price optimization and weight reduction.

This template describes the behavior of products created with additive 3D printing technology. The tested material used to produce the samples was polyactide acid (PLA). PLA is one of the most favourite material for 3D printing. This polylactide acid contains a metal additive. The standard dog-bone shaped samples reinforced with internal ribs arranged in a grid with 20% of the internal volume of the rib-filled sample were tested for tensile strength. The samples were subjected to different types of chemical degradation prior to the test. As a degradation agent, there was used an organic solvents. The result of the research is the effect of the degradation factor on the mechan-ical properties of these samples and possible use in practice, specifically in technology.

Prototype production is a key element in the process of developing a new product. The prototype is important both for the initial materialization of ideas and intentions for product design, as well as for subsequent assessment of the technological design of this design. 3D printing technology is also used today as a suitable technology for prototype production, especially for the possibility of relatively rapid adaptation to complex shape geometries, the ability to produce what would be difficult or impossible to produce with conventional technologies, and last but not least, the increasing availability of 3D printing equipment.This paper demonstrates the principle of production of auxiliary gauges, for checking the dimensions of a prototype product with complex shape, 3D printing and its further possible use in the conditions of an engineering company. The conclusions of the paper should show the possibility and suitability of integration of modern and classical production technologies in the conditions of piece or custom production.

The aim of the paper is to introduce the digital twin concept as part of the Industry 4.0 strategy. In the form of a case study, the procedure and outputs of the simulation of a specific production plant to-gether with its intermediate storage and output for the next plant are presented. In the research part is presented a simulation model of production lines and intermediate stock with material flow represen-tation. At the beginning of the research the analysis of production and logistics processes was carried out. The next part describes the programming methods used to record and redirect material flows between individual lines and stock. The simulation method using simulated production line models enables the digitization of dynamic production processes in enterprises. We expect that in the coming years there will be an increase in demand for the creation of simulation models of production systems in modern manufacturing companies that will try to implement the Industry 4.0 strategy and thus in-crease their competitiveness.

This paper deals with the use of lean manufacturing methods to streamline the welding line in the au-tomotive industry. The automotive industry is constantly developing and innovating its production envi-ronments and technology because of growing competition on the market and customer demands. Cur-rent trends of car makers include pressure to reduce costs and increase production efficiency. With the commencement of new technologies, the production lines began to innovate and the production cycle began to constantly accelerate. The paper deals with the reconstruction of the welding line, which produces parts for the rear axle of a compact SUV. The case study aims to identify bottlenecks and set innovation plans and their evaluation in possible implementation. In the paper, lean manufacturing methods are applied in order to deter-mine the ideal solution for ensuring the quality and ensuring the efficiency of the production line, lead-ing to cost reduction. Through these innovations and modernizations, the company will be heading for digitalisation that changes the core of the industry.

This document presents the characterization of the dynamic mechanical properties of a racecar's frame. First, it introduces the applicability of modal analysis, then the modal analysis of a lightweight vehicle chassis will be detailed, which is the focal point of this paper. This analysis was performed to determine some of the modal parameters, in order to reduce the noise of the vehicle, the probability of a component failure and to improve the comfort. The simulation part of the applied analysis was based on dynamic FEM (Finite Element Method). The measurement part of it was based on measuring the FRFs (Frequency Response Functions), with the help of accelerometers fixed at the nodes of the frame. The excitation signals were provided by a shaker connected to the chassis. In order to provide good quality results, the processing and evaluation of the simulated and measured data has to be done properly, which is discussed in detail. However, one dominant factor of a modal analysis is to find the optimal measurement setup. For this reason, the details of the measurement setup will be included. Hence one of the goals was to improve the coherence curves of the FRFs. Thanks to the presented techniques, the coherence curves managed to be improved and the results of the simulation and the measurement were found to be in good agreement.

This work was focused on the research of the different variability production deep-drawing sheets made of AlMg3 alloy which could influence on their deep-drawing properties e.g. non alloying elements Fe, Mn, heat treatment parameters and structure with aim to judge ascertained and analyzed properties of the sheets. The mechanical properties, mainly the highest elongation, and the other parameters (grain size, metallurgical purity), were measured due to they had had the main influence on the deep-drawing properties of the sheets made of AlMg3 alloy. For this research work had been obtained 5 deep-drawing sheets made of AlMg3 alloy with different production than chemical composition and heat treatment with the aim to realized ?complex analyze?, and to find up the best variant for production technology with the high deep-drawing properties.

Modern production systems requires high effectivity and flexibility with always increasing demands for precision as an imperative for more efficient components. The same apply for quality inspection providing data for feedback regu-lation of production processes. CMMs (coordinate measuring machines) which are flexible and universal in use yet very accurate and easy to automate are a standard mean for quality inspection. With many sensors available on the market, central fixed scanning heads with tactile scanning probes are a reference equipment for inspection of precise production of engine and transmission components. Tactile probes are right choice where very high accuracies and stability of results is required. Effectivity was allways a target in production processes and today the same pressure for effectivity and productivity is required from measuring machines, yet measurement strategies are often taken from measurement plans even 10 years old. This means that in old programs low scan speeds are used based on capability of older technologies and the approach of don´t change it when it works is common. This limits productivity of the whole quality control process. Motivation for this paper and whole research is to increase productivity and thus capaci-ty of quliaty inspection without compromising process capability. Lack of measuring capacity is usually solved by purchase of a new machine which may not be allways necessary. Primary motivation of companies supplying these technologies is not maximum efficiency of quality inspection, which in context of spare capacities ultimately means lower sales. Aim of this article is to describe influence of scanning speed and size of inspected feature on CMMs accu-racy. High-precision CMM control itself is not easy because with decreasing path radius dynamic effects of machine construction itself increase on measurement results. Accuracy of CMM measurement is then function of feature size being checked. This knowledge can be used for optimization of measurement plans in terms of productivity while maintaining sufficient measurement accuracy depending on required tolerance.

Small holes can be manufactured by several ways. It is important to define in what dimensions the small holes vary. Anyway, drilling is one of the oldest technologies of holes manufacturing. In small dimensions we use the term microdrilling for description. Beside this conventional way of manufacture there are also unconventional methods. Microdrilling bits very often break before they are worn. Therefore, the tool life of these bits its quite unexpectable. It is due to relatively high load against the drill bit strength. So, it is important to choose proper drill bit material, cutting geometry, construction, process liquid, clamping and cutting conditions. These parameters are import for achieving ideal conditions for microdrilling. Even a tiny change in pre-seted parameters can lead to destruction of these delicate tools. Fiber arrays are designed and manufactured for precise positioning of optical fibers in row (1D) or in plate (2D). Fiber arrays can contain most of fibers including polarization maintaining fibers (PMF).