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The article presents new possibilities of simulation software and its application to improve the pro-duction structure. In many enterprises, the basic issues are related to the determination of planned tasks for individual positions, calculating the demand for employees, taking into account their skills and qualifications, calculating work costs, determining work efficiency and its dynamics. Therefore proper work organization consists in setting the course of work in such a way as to obtain maximum results with the least amount of work by man and machine. The article presents the problem of per-sonnel allocation to the production line. The basic stages of developing a simulation model of this process are discussed, including all necessary information and inputs. The results shows impact of the selected simulation scenarios to the workload level of the staff and the duration of the production process. In this concept, to solve the problem a simulation model of the production process was built. A new generation of 3D FlexSim simulation environment with an integrated OptQuest optimi-zation module was used.

The article deals with the use of SPC tools to manage and improve the machining process - drilling furniture elements. The content of the article is to use such SPC tools as basic statistical parameters, box plot, histogram, classic and special control charts, and process capability indicators to assess the drill-ing process and to indicate areas to improve. The article indicates the power of SPC tools in woodwork furniture process control and power of using the Statistica program from TIBCO Software Inc. in this area. SPC tools bring a lot of important and useful information about the analyzed drilling process, its weaknesses, which contributes to the improvement of the process. The conducted study has been shown that the tested drilling process requires improvements, in particular in the area related to the machine and man. The activities that should be implemented to improve the quality of the process were defined, including implementation of the Poka-Yoke system, development of a maintenance inspection schedule, a visual manual for machine setup, employee training with a verification exam, introduction of an employee's suggestion system, modification of the company's motivation system. SPC tools helped to identify the source of process problems, defined a process’s stability and capability to meet a customer requirement, and assist with other insights, that were used to define improvement action.

This paper focused on axial flow pump high operation, reliability, and long service life at different frequency of rotation (DFR). The efficiency of an axial pump varies considerably depending upon the conditions under which it must operate. This article concentrates methods related to the reliability analysis of pumping system operation by a frequency converter. Initially, it is focused to analyze the behavior of individual characteristic curves of the axial pump to find how can be applied for the determination of the most efficient frequency of rotation. Axial flow pumps are often controlled by adjusting their rotational speed, which affects the resulting flow rate and output pressure of the pumped fluid. In addition, the head and flow of fluid transported at different frequencies of rotation, to produce a map of reliability characteristic curves to verify the similarity rules for pumps recommendable operating region are discussed. The results showed that the recommendable operating region for a different revolution per minute of axial pump can be determined with efficiency. If the axial flow pump is driven outside its operating region, the efficiency decreases, and the reliability and long service life may be affected.

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.

Friction is closely related to every moving machine and fundamentally affects efficiency and service life. Wear tracking of moving and non-moving parts of the engine mechanism is important for expressing the wear trend. The wear and tear trend is specific for gasoline engines in urban traffic. The increase in the number of abrasive non-ferrous particles (Al, Cu, Ni, Cr, Sn, Si) is monitored in Škoda Octavia vehicles. The statistical evaluation of nomogram the wear and the determination of the optimum oil change interval of a vehicle group with sparkignition engines are performed for individual non-ferrous particles. The main aim of the article is to propose and verify the method of determination of the optimal oil change interval using Atomic Absorption Spectroscopy, Thin Layer Chromatography and using limit values of discriminatory analysis. On the basis of the results of the analyses, it is clear that the oil change interval by the manufacturer is inadequate and the oil level must be monitored.

With the rapid development of modern manufacturing technology, people have higher and higher requirements for the quality of mechanical products, and the precision of machine tools for processing mechanical products has gradually increased. Therefore, the development of static pressure guides is particularly important for precision processing industries. The load on the guide rail has an important effect on the thickness of the oil film, and the stability of the oil film thickness directly determines the accuracy of processing. In order to obtain the best control method for the thickness of the oil film, the dimensions of the hydrostatic guide rails and the three-dimensional model of the guide rails were designed and calculated in this paper, and the fuel supply method of the guide rails was determined. The simulation model of the oil film was established and imported from the AMESim software into the FLUENT software to obtain the pressure, velocity, and temperature distribution maps of the oil film. And the pressure distribution data was processed after summarizing. Combined with the relevant mathematical models, the mathematical model of the oil film thickness was finally obtained. Then the Simulink software was used to analyze and the PID control was introduced for comparative analysis. The DOB anti-interference control theory was introduced, and the anti-interference control algorithm was improved. The anti-interference algorithm adapted to the oil film thickness control complete the programming of the modules of the interference controller. The anti-interference control section was created in the Simulink software, and the system of the DOB module was finally completed after packaging. In order to verify the method in t his paper, a static pressure rail test bench was set up, and relevant detection tests were completed. The results of the above studies showed that the control performance was greatly improved after introducing the anti-interference algorithm adapted to the oil film control system.

This paper deals with the design of a multi-part mould for the production of a carbon fibre medium-large compo-nent. The design and forming of a medium-large component which is defined by a closed structure and has high demands on dimensional accuracy is a very complex process. The goal was to design a simple manufacturing pro-cess for a negative mould. There are many different ways to design and manufacture this type of mould. One pos-sible solution was designed and tested. This paper describes the case study of a carbon fibre monocoque of a small racing car. The first step was to define the requirements of the final product and the negative mould. The next step was to design a multi-part mould with one main parting plane and two minor parting planes and define the number of steps needed to build a negative mould. Another problem is how to define the position of the general anchor points that determine the final product. In this case the procedure of transferring the hole from a positive to a negative mould was defined.

The article deals with analytical and experimental solution of vertical oscillations of a mechanical system of bound bodies. The content of the article is to perform an analytical solution of the vertical oscillation of a system of bodies using the computer program MathWorks Matlab and MS Excel. Furthermore, an experimental investigation on a laboratory model of a mechanical system of the same parameters was proved. The aim of the work was to compare the analytical solution with the experimental method and to check the accuracy and applicability of analytical methods for the solved mechanical system.

This article is aimed at design of a support and a tension mechanism to be mounted on a wheel-tracked chassis of a mine clearing machine. The subject machine serves to detect and disposal mines in terrain. The main advantage of this machine is the possibility to use it from the safe distance thanks a remote control. The wheel-tracked chassis mounted on the machine ensures that the machine is able to overcome extreme obstacles of a terrain. The solved design of the wheel-tracked chassis can be modifying to move using just wheels for better driving properties on metalled roads. Current design of the wheel-tracked chassis goes out from the older technical solution, which has been designed for a four-wheeled machine. The latest version of the chassis is designed for a six-wheeled machine. Application of an original structure of the chassis meets problems consisted in formation of ckacks in tracks struc-ture therefore the current structure of tracks has to be modified in order to meet all requirements in term of strength and long-term operation. At the same time, two design of a tension mechanism are presented. A tension mechanism is additional device, which will be mounted to the chassis and it will ensure the optimal position of tracks in every load case.

This paper mainly studies the hydrostatic turntable of precision milling and grinding compound machining center in aerospace processing equipment, and innovatively designs and analyzes the mesa. It is proposed to replace the traditional 40Cr with imported marble for the mesa. Firstly, the vibration model of the hydrostatic turntable is carried out. ANSYS Workbench software is used to compare and analyze the original and marble materials. In the process, the static characteristics and the difference of first-order modes of the two materials are compared. In addition, the analytical results are used for manufacturing. The results show when the applied force reaches the limitation 29400N, the maximum displacement of 40Cr increases sharply to 8.9406μm; while the marble material reaches 2.6μm. Meanwhile, it is obtained that the power consumed by marble is reduced by 39.12% compared with 40Cr. The weight of marble is reduced by 39.36% compared with 40Cr. Marble is about 21.59% higher than 40Cr in the comparison of vibration mode results

The authors presented paper deals with experimental measurement and evaluation of nanomechanical properties of hard turned and grinded surfaces on the cross section specimens made of the 33NiCrMoV15 steel. 33NiCrMoV15 steel was selected to perform for all realized investigations. Even before the start of the experi-ments that investigated the effect of hard finish turning against grinding, it was necessary to subject the investi-gated 33NiCrMoV15 steel to basic research with regard to its chemical composition, fundamental microstructure and basic mechanical properties. The microstructure was performed on Neophot 32 optical microscope. Chemical composition was realized on the spectral analyzer Spectrolab Jr CCD. Mechanical properties, like nanohardness H and reduced Young modulus Er were subsequently performed on the Hysitron TI950 Triboindenter with a Cube Corner measuring tip, and evaluated by software Triboscan. Based on the acquired values, a 2D nanostructure of the distribution map of s H and Er was then evaluated in Matlab. This scientific research, together with all measured and calculated values, is the fundamental that will help to optimizing the quality and used all these results to optimize presented material and technological processes in term of surface integrity.

If failure occurs in gear wheels in a racer motorcycle gearbox, the possible causes are manifold: inadequate material, improper care (poor lubrication, incorrect assembly) or inadequate thermochemical treatment procedure. This investigation focused on spur wheels of chromium-nickel Czech Standard (ČSN) 16720 steel containing 0.18 % C, 0.4 % Mn, 1.5 % Cr, 4.25 % Ni and 1 % W. The steel had been quenched to 60-62 HRC and the case hardening depth was 0.8 mm. The client requested that these wheels have a life of 100 hours. The failure occurred while the wheels were in operation. The fracture surfaces in the wheels were examined in a scanning electron microscope (SEM). The fracture surfaces were prominent in the failure locations. EDS point analysis in the SEM revealed spots with higher chromium levels on the fracture surfaces. The average size of these spots was several dozen micrometres. The spots were suspected to have caused or contributed to the failure. A hardness profile across one tooth was measured using a microhardness tester. In addition, the thickness of the carburized layer was determined. Quality of the surface was assessed using macrophoto-graphs taken with a low-power stereomicroscope. In addition, metallographic sections were prepared and observed in a scanning electron microscope (SEM) and light microscope.

With the determined parameters of cutting speed, feed rate and back cutting depth, cemented carbide tool was adopted to dry cut 304 stainless steel, exploring the tool wear failure mechanism and its effect on the surface quality of the workpiece under different cutting times. The morphology of the tool surface is observed by scanning electron microscopy, and the component of the tool is analyzed by energy dispersive spectroscopy. The three-dimensional microscopic shape of workpiece surface is observed by a three-dimensional shape analyzer and the surface rough-ness Ra was measured. The results indicate that during the process of 6-minute cutting, the abrasive wear and adhe-sion wear are occurred on the tool, the surface quality of the machined workpiece is good; during the process of 12-minute cutting, oxidation wear is appeared while the tool subjects abrasive wear and adhesion wear, and the surface quality of the machined workpiece become pool; during the process of 18-minute cutting, the tool is under the com-bined action of various wear mechanism. Because of the passivation of tool nose, the surface quality of the work-piece is deteriorated, and it can’t meet the requirements of finish machining. In the process of dry cutting workpiec-es by cemented carbide tool, the tool suffers abrasive wear, adhesion wear and oxidation wear. The surface quality of the workpiece is declined due to the passivation of the tool nose.

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 sectional fire ladders, made of aluminium alloy AA6063, belong to the basic equipment of the fire department of the Czech Republic. The use of these materials facilitates the deployment of ladders for firefighting, but it also brings with it certain pitfalls. During the use of ladders in extinguish-ing fires, their thermal influence and subsequent changes in mechanical properties may occur. This is highly dangerous and can lead to people falling from these ladders due to a significant reduction in the mechanical properties of the material.

Carburizing is used in applications where there is a high demand for surface hardness and abrasion resistance along with core toughness requirements. Carburizing is mainly used for parts which are subjected to abrasion, such as shafts, pins, gears, cams, etc. At the same time as the hardness of the surface layer increases, the fatigue limit of the steel increases after carburizing. The article deals with the evaluation of surface quality of carburized steels 16MnCr5 and 14NiCr14 in terms of surface texture change and dimension change after application of car-burizing. The analysed steels are used mainly in the production of gear wheels for gearboxes of wheeled, tracked and artillery. Furthermore, the coefficients of friction and wear were evaluated on these steels. The functional surfaces of heat-treated steels were analysed after grinding and after gas carburizing. The evaluation of the sur-face quality results in a deterioration of the surface roughness and an increase in dimensions after carburizing. The coefficient of friction after carburizing reaches a higher value compared to ground surfaces, while the coeffi-cient of wear decreases.

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.

From the viewpoint of residual stresses and microstructure of ground surface, Inconel 713 superalloy is an attractive material since it is frequently used in high temperature gas turbine applications where residual stresses are relevant for service life. The goal of this contribution is to find whether there exists a relation between grinding parameters and final surface integrity parameters such as residual stresses, roughness, crystalitte size, and generally, microstructure. Highly productive creep feed grinding has been applied to produce both simple flat areas and complex fir three blade root. It has been found that the used grinding method lead to very thin deformed layer on the surface with compressive residual stresses and fine crystallites. Moreover, the detailed analyses have been carried out in order to pinpoint plausible reasons behind crack origination.

In order to improve the transmission efficiency and the service life of ordinary cycloid gear, 5 kinds of new cycloid gears with variable cross section are devoleped based on the principles of traditional cycloid drive. These new cycloid gears include concave cycloid gear, drum cycloid gear, spherical cycloid gear, oblique cycloid gear and cone cycloid gear. The general mathematical equations of these new cycloid gears are obtained and the characteristics of these new cycloid gears in transmission applications are analyzed in detail. A new method on the end milling tooth profile surfaces of cycloid gear using ball end mill is proposed. 5 axis numerical control simulations of these cycloid gears are conducted and the tool paths of machining cycloid gear are obtained. 5 kinds of cycloid gear with variable section are machined on five-axis CNC machining center, which verifies the correctness of the NC program. The study will provide a new way of designing and machining cycloid gear.

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.

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.

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.

This contribution is divided into two sections. The first one deals with identifying the cause of fracture in a ring, which fractured after weld surfacing. Optical and scanning electron microscopy and hardness testing were employed. Chemical composition was determined using the GDOES and EDX methods. Although weld surfacing has led to fracture in the base material, the actual problem was in the inadequate microstructure of the base material. Microscopic analysis revealed that it was heterogeneous. It contained distinctive segregation bands with bands of complex carbides and pearlite colonies, which are undesirable. The microstructure of this steel should be fully austenitic. In order to remove the heterogeneities, solution annealing was proposed and carried out successfully. The second section of this paper explores the options for revealing the microstructure of Hadfield steel. Etching reagents from the literature and authors' experience were put to test.

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.

The combustion engine is a very widespread energy source for many machines and devices. Diesel, gasoline, LPG, CNG, as well as many biofuels such as ethanol, butanol, etc. are used as propellants at the present time. During the running of the internal combustion engine, some fuels penetrate into the crankcase and degrade the engine oil. This potentially reduces the lubricating ability of the oil and changes its degradation process. Submitted paper follows possible changes in lubricating capabilities of oil used in engines with specific fuels: n-butanol, LPG and diesel. Different type of fuel used in combination with an inappropriate operating mode might have a significant influence on the oil and consequently on the engine wear (monitored by a laser particle analyzer). This paper also deals with presence of various types of particles in the engine oil. Results demonstrate proceeding changes noticed in oil and also how was the degradation process effected.

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.

This paper is focused on the preparation of the magnesium composite materials by extrusion of the chemically treated powders. Microstructures with partially preserved borders between particles containing specific elements depending on the preparation method were created by extrusion. Compressive mechanical properties of extruded chemically treated powders were similar to material prepared from atomized powder. The corrosion rate was reduced by three times in the case of chemically treated powder compared to the pure Mg. Ignition temperature of the chemically treated powder increased by up to 200 °C compared to the atomized powder, while ignition temperatures of the extruded samples were only slightly improved.

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.

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.

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.