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Plastic injection process is one of the techniques used to manufacture plastic products. The technique is widely used due to its higher and faster production capacity and low cost. However, production process problems are often found, one of which is inappropriate process parameters settings, which may cause product defects. This paper presents a method using combination of Taguchi method, Moldflow simulation and PSO to optimize plastic injection molding process parameters. Moldflow simulations were run to obtain volumetric shrinkage values resulting from each combination of parameters setting selected by means of OA. In adopting S/N ratio technique of the Taguchi method, the study adhered to the principle of "the smaller the better". The ANOVA method was also used to analyze the effect of each process parameter on volumetric shrinkage and a regression analysis was used to establish the equation used for the application of the PSO method to optimize plastic injection process parameters. This method was applied for the production of number plate brackets from PP AZ564 material. The study concluded that the application of the combined Taguchi-Moldflow-PSO method could reduce volumetric shrinkage from 6.05% to 4.24%.

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.

This article presents a new technology of obtaining the flat products with an ultrafine structure. The ultrafine-grained structure is obtained by using severe plastic deformation which is developed by the helical rollers. The stress-strain state (SSS) of the workpiece during rolling process in the helical rollers and longitudinal wedge mill is investigated in this scientific paper. The quantitative data has been obtained by the finite element method and MSC.SuperForge software; as well as the basic SSS distribution patterns, the temperature in simulating the rolling in the helical rollers and longitudinal wedge mill with different number of passes and the single reduction have been established. The rational technology of rolling the two-phase titanium alloys was developed and tested in the laboratory. The special attention is paid to analysis of the influence of the rolling conditions in the helical rollers and longitudinal wedge mill on the formation of VT6 titanium alloy microstructure.

Accuracy of work-pieces of complex free form surfaces is achieved by tolerancing, producing and metrology of workpieces. The tolerance zone is defined by form tolerances, their orientation and location on the work-pieces. Tolerances for complex form surfaces are specified by line profile tolerance or surface profile tolerance. These tolerances control form or combination of size, form, orientation and location. In a machining process the impact of machining parameter settings on the final surface quality will be researched. The influence of toolpaths in connection with the SH (Scallop Height) parameter setting on production accuracy and quality of machined surface will be compared. For geometry verification of the complex form surfaces are coordinate measurements used. The measurement area is modeled with the equations in CATIA V5. The data of machined surface obtained through the contact coordinate measurement are processed using the coordinate system adjustment via the RSS minimization by the Newton method in Matlab/Octave. Calculated values of surface profile deviations at individual machining strategies are used to achieve the required quality of machined surface through optimization of the machining parameters.

Milling is one of the oldest methods of metal machining. This technology has been developed over a long time. The last milestone is the use of composite materials for the construction of cutting tools. However, there are other pos-sibilities for improvement offered by new production methods such as Metal Additive Manufacturing. The paper deals with machining experiments using a lightweight milling cutter with a lattice structure. The results of machin-ing are compared to the capabilities of a solid milling cutter. The evaluated parameters are: cutting forces, blade wear and surface roughness of the workpiece. Based on these parameters, it was not possible to confirm the benefit of the lightweight version for machining.

Technological conditions of tube drawing influence the properties of the resulting products. In addition to mechan-ical properties, they also affect the geometry of the drawing tube ? macro geometry and microgeometry. The paper presents the results of measurements of macro geometry (roundness and cylindricity) and micro geometry (surface roughness) of the outer surface of the drawn tube. Tubes (STN 41 1353) were drawn through dies with different reduction angles (6° and 12°). On used fixed mandrels were ground the straight and spiral grooves. The effect of these grooves and hence the deformation itself has also been manifested on the outer surface of the drawn tube. On the measured roundness profiles are significantly noticeable places where the land and the groove were when drawing. This effect can also be observed on the deteriorated measured values of roundness. On the meas-ured values and roughness profiles of the outer surface of the drawn tube can also be observed the difference be-tween land and grove.

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.

The heat treatment of the heat-treatable aluminium alloy forgings includes cooling from the solutionising temperature. After heat treatment, residual stresses remain in the forging, which are due to temperature gradients during cooling. The effect of these residual stresses on the forging properties can be significantly influenced by other technological operations, including artificial aging, machining, and surface treatments. The influence of the surrounding environment can also play an important role. Because in connection with the residual stresses after heat treatment we often encounter cracks in forgings, this paper is devoted to an overview of factors that influence cracks. The typical examples of damaged forgings are discussed and explained the circumstances that caused cracks under the influence of residual stresses.

The paper reviews the results of an evaluation of the influence of the operating factors on traction-adhesive prop-er-ties of a locomotive. Planning of an xperiment was performed for two locomotives ?freight locomotive 2TE116 and shunting locomotive TEM103. The input for performing the numerical experiment was variation of 6 factors: the change in the wheel diameter of the first wheelset due to wear, the change in the mass of the locomotive as a result of the change in the amount of the fuel as well as the wheel rims wear, the impact of the friction damper in the primary suspension, change in the primary and secondary suspension stiffness due to operation. Regression equati-ons were obtained in code and natural form, which describe the effect of operating factors on the coeffi-cient of utilization of the locomotive adhesion mass.

The presented paper deals with determination of mechanical properties of materials used for 3D printing (ABS, nylon and PLA). The theoretical part of the paper characterizes the static tensile test by which selected me-chanical properties of samples were evaluated. The practical part of the paper characterizes the additive technolo-gy Fused Deposition Modelling, by means of which standardized plastic samples were printed on the 3D printer. The practical part also deals with analysis of selected mechanical properties of samples made by Soft Tooling technolo-gy. SG 2000 and SG 145 polyurethane resins were used for the production of samples using Soft Tooling technology. Individual samples were analysed using selected tests (tensile test and hardness test). Surface integrity parameters were also determined for 3D printing test specimens. Parameters (tensile strength, tensile modulus, tensile strength and hardness) that were statistically processed were selected for each test. The paper is finished evaluating the re-sults obtained, which were compared with those given in the material sheets.

The given paper deals with the wear of the tensioner which is produced from aluminium alloy and used of the motorcycle timing chain. This component was made due to the unavailability on the spare parts market. The AlMgSi1 alloy was chosen for this purpose, taking into account the requirements for producing of the tensioner. After production, the tensioner was put into operation where its functionality was regularly controlled. The suitability of the selected material was checked after the tensioner was removed. Possible damages and structural changes in the material were assessed using a scanning thermoemission electron microscope. Detection of the chemical composition of foreign particles trapped on the surface of the tensioner from engine oil during the operation was performed by EDS analysis.

Projection welding belongs to the group of resistance welding technologies. The basic process parameters are the welding current and the current flow time. Although the resistance projection welding of nuts on galvanized steel sheets is widely used in industry, only a few research articles have been published. The resistance projection weld-ability of the fasteners on metal sheets is not as well understood as the resistance spot weldability of the sheets, so complex studies for the wider application of resistance welding of nuts in the automotive industry are still needed. This research is aimed at valuation the effect of resistance projection welding parameters (steel nuts on galvanized steel sheet DP 600) on joint properties. The hard welding mode (high welding current, clamping force and short welding time) provided 2 times higher strength of the weld joints as the soft welding mode. When using the soft welding mode, an increased Zn concentration from the sheet metal coating was measured in the transition area between the welded materials at the folding locations. When applying the hard welding mode, only a slight in-crease in the Zn concentration was observed at the inner boundary of the weld joint.

The experimental investigation of the vertical vibration of the vehicle is presented. The vibration of the two axles vehicle is excited by crossing of the vehicle over the transverse speed bumps on the road. The methodology is oriented upon the quarter, half and full model solution. The full geometry model is the most suitable model for the vertical vibration of the vehicle. The full geometry model is capable to describe geometric and construction asymmetry of the vehicle. The methodology of an analytical solution of the symmetry and asymmetry distribution of the vehicle and load is presented. Also, symmetric and asymmetric excitation is involved to the solution. The Heaviside?s function is applied for the excitation of vibrations. The presented methodology was applied to the experimental work with trolleybus Tr 21. The normalized speed bumps were used for the experimental setup. The vertical displacements, velocities and accelerations of axles, body of the vehicle. The acceleration of the vehicle chassis under driver seat was also recorded. This accelerations have significant effect on the comfort of driver and consequently on his/her fatigue and health condition.

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.

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.

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 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 paper describes a search for an optimal organization of the drying agent motion in the convection dryers. An overview of the main methods on how to reduce the energy consumption for the convection drying of the disperse materials is presented. The use of the multistage shelf apparatuses with a differential thermal regime for the con-vection drying of the disperse materials is justified. The work contains the results of a computer modeling on de-termining the drying temperature and moisture characteristics with the use of various methods of the organization of the drying agent motion. The model is realized implementing the author?s software product Multistage Fluidiz-er?. The software product enables to automatize calculation simultaneously by several optimization criteria and to visualize calculation results in the form of 3D images. The engineering computation of sectioning devices meth-odology with fluidized bed of particles is based on the calculation results. The automated calculations results give a base to design industrial drying device with a differential thermal regime.

The aim of the work was to assess influence of technological parameters of casting on thickness and continuity of decarburized layer of castings and their mechanical characteristics in order to suggest adjustment in the production process according to discovered results. The samples for experimental work were taken from one type of casting made from steel 42CrMo4. The thickness of decarburized layer was examined on the samples cast at different temperatures of ceramic mould and at different temperatures of casting. Influence of the wall thickness of the casting was also evaluated. It was ob-served that changing temperature of the ceramic mould does not cause a significant change in the decarburized surface area of the casting. The influence of the casting temperature of the metal and the shape of the casting is more pronounced in the formation of the decarburized surface layer. As the casting temperature rises, the thickness of the decarburized surface layer of the casting increases. With the increasing wall thickness of the casting, the surface decarburization layer also gets thicker.

The objective of this paper was to investigate and respond to the quality and strength of CMT welds that were sub-jected to degradation effects and subsequently to tensile testing. The tensile test was recorded using AE acoustic emission. The experiment focused on the quality of CMT welds (Cold Metal Transfer) and the resistance of these welds to corrosion degradation. Welds are generally exposed to environmental influences such as high stress, stress and degradation effects. The combined effect of these factors may in some cases result in the destruction of weld joints. For this reason, emphasis is placed on the quality of welds and their resistance to environmental influ-ences. For this measurement there were ten samples prepared, divided into two groups, each having five samples. One group was subjected to corrosion degradation, while the other one was at the same time subjected only to envi-ronmental influences. Subsequently, all samples were subjected to tensile testing. The course of this test was rec-orded using the AE acoustic emission, where the AE sensor was attached to each weldment to record dislocations during the tensile test. Named values were evaluated in the Dakel–Daeshow program.

The article deals with geopolymer binder system for core production, especially by dehydration technology and comparison with PUR cold box amin technology. A sodium-potassium type of geopolymer binder is the subject of the research. The goal of the article is the core production and observing of technological properties, storing cores, usage of refractory coating evaluating of properties during the pouring and decoring of casting. The main target of the experiment is casting quality. It was stated that the final surfaces are much more better than PUR cold box amin technology and the internal casting quality is the same, it means without inadmissible internal defects. Worse decoring times were observed. It has been confirmed, that neither emissions, fumes nor unpleasant odours are generated during the production procedure nor during pouring.

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.

This authors presented article deals with the size of heat affected zone (HAZ) at specific technological processes (cutting and welding techniques). Armox 500 steel was selected and used to perform all realized experiments. Even before the start of the experiments that investigated the effect of HAZ on cutting and welding, it was necessary to subject the investigated Armox 500 steel to basic experimental measurements with regard to its chemical composition, fundamental microstructure and mechanical properties. The microstructure was performed on Neophot 32 optical microscope. Chemical composition was analysed on the spectral analyzer Spectrolab Jr CCD. Mechanical properties, like nanohardness H and reduced Young modulus Er were subsequently measured on Hysitron TI950 Triboindenter with a Cube Corner measuring tip, and evaluated by software Triboscan. Based on the measured values, a 2D nanostructure of the distribution map of s H and Er was evaluated in Matlab. This scientific research, together with all measured and calculated results, is the fundamental that will help to optimizing the quality and used all these results to optimize presented material and technological processes.

The subject of the article is a comparison of new and used powder for 3D metal printing. The powder is 316L stainless steel manufactured by Renishaw. The powder used was taken from the RENISHAW AM250 printer after use. Powder manufacturer Renishaw recommends using 15-45 micron powder in their 3D metal printers. An im-portant parameter of monitoring is the chemical composition of the metal powder and its changes during the thermal treatment during laser sintering. Another important parameter of a metal powder is its mechanical prop-erties, which determine the flowability, consistency and uniformity of powder application. By using an inert at-mosphere for sintering and storing the powder, these chemical changes can be prevented, especially against the formation of nitrides and oxides at elevated temperatures.

In the recent years, the demand for weight reduction in modern vehicle construction has led to an increase in the application of hydroforming processes for production of automotive and aerospace lightweight components. The tube hydroforming measurement site (TH stand), designed and built at Warsaw University of Technology allows both die, and free tube hydroforming processes to be performed, thereby making it possible to obtain information about the material, as well as optimal process parameters [1][2]. The present freshly patented method for metal tube hydroforming is dedicated to short product series or even single products and prototypes [3]. The method is applicable to forming difficult-to-machine materials. The well-known techniques use dies made of plastic or wood, especially to form short product series. The use of moulding sand and properly prepared geometry of casting mould makes possible shaping materials at high temperatures, which could not be done in previous short series solutions, where a plastic or wooden die were used. [1] Sadłowska H., Jasiński C. Morawiński Ł., Strain measurements on the tube hydroforming testing machine, Archives of Metals and Metallurgy Vol. 65 , Issue 1, 2020, pp. 257-263 [2] Sadłowska H., Odkształcanie się rur podczas swobodnego rozpęczania hydromechanicznego na stanowisku TH, w: Prace Naukowe Politechniki Warszawskiej. Mechanika, Vol. 267, 2015, ss. 25-30 (in Polish) [3] Patent No. PL424401, Kochański A., Sadłowska H., Bulletin of the Patent Office of Inventions and Utility Models vol. 17_2019, pp. 11

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.

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.

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.

Effect of addition of cryogenic treatment to a standard heat treatment of aluminium alloy AW 7075 was tested in this work. Used heat treatment consisted of solution annealing at 470 °C for two hours and precipitation aging treatment at 130°C for 14 hours, 120 °C for 24 hours or natural aging at room temperature for 60 days. One set of samples was processed by solution annealing and aging treatment and the second set of samples incorporated 24 hours long cryogenic treatment at -185 °C between the same solution annealing and aging. Both sets of samples were characterised by tensile testing, notch impact testing, hardness measurement, microstructure analysis and wear and corrosion resistance tests. Obtained results were compared for corresponding processing with and with-out cryogenic treatment. While impact toughness and corrosion resistance were decreased by cryogenic treatment, tensile strength and wear resistance were on the other hand improved.