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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.

The quality of machine parts is determined not only by the quality of the materials themselves, but also by their heat treatment, which also includes frequently used chemical-thermal processes, such as case-hardening, leading to an increase in the mechanical properties of the surface layers of the material. Heat treatment involves thermal diffusion processes, which are quite complex and therefore there is always a certain probability that the desired material state will not be created. It is therefore desirable to have control methods, preferably of a non-destructive nature, which can detect imperfections and thus prevent future damage that could occur in this way. The paper deals with the use of commonly used non-destructive material testing techniques such as eddy currents, ultrasonic control and acoustic emission method to verify the correctness of thermal and case-hardening processing of steels.

The article focuses on technological procedures of coating of metal molds made from Al-Si alloys, espe-cially used for making tyres. The idea is to create coating on aluminium based metal molds in order to reach a higher number of production cycles between individual cleaning operations in tyre making tech-nology. The experiment was based on a preparation of experimental samples, which were coated with a teflon based product with the addition of nanoparticles (eg. TiO2), in other words, particles as large as tens of nanometres, which were mixed into the teflon solution in a particular concentration. After creat-ing the coating, the experimental samples were put under a thermal load in various thermal modes. Fu-thermore, roughness, coating resistance, and changes after the thermal load were subjects of the study.

The article presents the results of the use of quality instruments – tools and techniques – in order to reduce surface defects of steel structures on the example of a selected element – engine cover of asphalt milling machines. The article shows the potential of using selected quality tools – basic and new – in the service of quality analysis and improvement. Quantitative analyzes were presented out using the Pareto-Lorenz diagram and the c control chart, qualitative analyzes using the Ishikawa diagram and the FMEA method, quantitative & qualitative analyzes using the interrelationship diagram and matrix diagram, and it was proposed quality improvement using qualitative tools such as affinity diagram, and PDPC diagram. The most common defects of painted surfaces turned out to be improper thickness and surface contamination. As it has been shown, the experience of employees is largely responsible for the cause of these defects, which was also confirmed by other analyses carried out with the use of quality tools. The training was the most frequent method of prevention. It has also been shown that special attention should be paid to quality control, its effectiveness, and quantity. The article proves that correctly used quality tools can contribute to the improvement of the quality of manufactured products, helps in solving various quality problems.

Exploded view is a kind of schematic view which decomposes the assembly into parts and arranges according to certain rules to explain the product structural relationship and guide the relevant technical personnel to carry out product assembly or maintenance. It is necessary to consider the visibility constraints and explosion sequence rules to construct the exploded view. Manual creation will lead to repeated modification and low efficiency. In this paper, a projection based algorithm for automatic generation of exploded view is proposed. In this method, the explosion set of products is constructed based on disassembly matrix and the assembly sequence of complex products is represented as a set of ordered hierarchical exploded view, so as to ensure that the exploded view can clearly express the feasible assembly sequence. The projection interference detection method is proposed to ensure the visibility of the exploded view under a given angle of view, and the method of selecting the explosion direction is proposed to improve the compactness of the generated exploded view, and the explosion direction guideline is established to improve the readability of the exploded view. The algorithm has small storage space, fast search speed, and is not limited to a single specific perspective, so it is more general. The feasibility and efficiency of the algorithm are verified by an example of automatic generation of explosive drawing of fixture model.

The work is focused on comparison of ballistic efficiency of homogeneous laminates consisting of one type of prepreg based on aramid or UHMWPE and ballistic efficiency of hybrid laminates consisting of combitation of chosen prepregs layered in different order. For preparation of hybrid laminates the two types of aramid prepregs and two types of UHMWPE prepregs were chosen. The laminates were subjected to ballistic testing by fragment simulating projectile FSP G5 and their ballistic efficiency was evaluated by determination of ballistic limit V50. For more complex assessment of tested laminates with regard to ballistic efficiency and also their areal weight, the ballistic weight coefficient K, which is defined by quotient of V50 and areal weight, was determined for each laninate and then compared. Besides the ballistic efficiency the coherence of laminate layers after pressing and after shooting was also observed.

AISI 316L stainless steel is widely used for multiple applications because of its good mechanical properties and corrosion resistance in multiple environments. However, the long exposure of AISI 316L steel to aggressive environments containing chloride ions limits its electrochemical performance significantly. The objective of this research is to develop and evaluate a thin cerium oxide-gelatin nanolaminate coatings for corrosion protection of the spin-coated AISI 316L stainless steel in 3.5% NaCl solution as the corrosion medium. The nanolaminate coat-ings were evaluated by the potentiodynamic polarization technique and the characterization of the coatings was performed by using XRD, SEM, and EDX. The results show that the corrosion behaviour of CeO2-gelatin nano-laminate coatings significantly improves the corrosion behaviour of the coated AISI 316L steel. The results also confirm the formation of homogeneous and crack-free coatings without any noticeable defect. One-way ANOVA analysis was used to examine the statistical significance of coating types. The novelty of this research is the development and preparing nanocomposites coatings by using gelatin as a gel matrix for nanocomposites powder dis-persion instead of the traditional methods to improves the uniform and localized corrosion of the AISI 316L steel. The results showed that the prepared coatings significantly improved the uniform and localized corrosion resistance of the AISI 316L steel.

Cemented carbides belong to one of the most important groups of tool materials, whose percentage among all other materials used for cutting tools has reached about 50% in the global industry. Powder metallurgy methods have been used to produce cemented carbides, of which spark plasma sintering (SPS) is considered highly prospectiveThis paper presents the results of preliminary research concerning the effect of the fraction of the binder phase and sintering temperature on the microstructure, density, hardness and resistance to brittle fracture of cemented carbides produced by spark plasma sintering. The test materials were WC powder with a purity of min. 99.5% and Co powder with a purity of min. 99.8%. The obtained mixtures (WC-3Co, WC-6Co and WC-9Co) were sintered using the SPS method at 1300°C, 1350°C and 1400°C. The heating rate was 400°C/min. The pressing load was 80 MPa. Density measurements were carried out using the Archimedes method in accordance with PN-EN ISO 3369:2010, while hardness measurements, using the Vickers' method, were performed in accordance with PN-EN 23878:1996. Resistance to brittle fracture was determined based on the measurement of the length of cracks formed on the corners of the indentation. The observations of the microstructure and analysis of chemical composition were carried out using the scanning electron microscope. The phase composition of the obtained materials was determined by means of X-ray diffractometry.

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.

In the present study, local defects in deep groove ball bearings are studied as forward and inverse problems. To this end, the separation-integration method is applied for modeling the forward problem. It is assumed that the inner race of the rolling element is multi-DOF, while the outer race is deformable along the radial direction. Then the problem is modeled with concepts of the finite element method. The contact force for the rolling elements is described by the nonlinear Hertz contact deformation. Various surface defects originating from local deformations are introduced into the developed model. Since the outer ring can be coupled with the FE model of the housing, the developed bearing model is capable of considering the transmission path of the bearing housing. Then model parameters are modified to reach better performance in predicting local defects. Through translating the inverse problem into the comparison of the geometric distance, measured indicators are used in the defect detection process and the relative location and size of defects are predicted. Finally, the defect range is established to evaluate the fault severity. Obtained results demonstrate that the proposed method is effective and accurate in the studied cases.

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 milling process is widely used industrially and the quality of the obtained milled products should be controlled because it affects their performance in exercise. This work correlates the quality of the machined surfaces with the adopted locating system, the shape deviations of the workpiece datum and the machine tool. An analytical model was set up and implemented through Matlab® to simulate the quality effects of a milling process. It was applied to two face milling processes characterized by two different locator configurations. It was proved that machine tool volumetric error influences the flatness of the milled surface, while the locator configuration and the datum form deviation affect the orientation of the milled surface, as should be actually.

The article concerns the testing two thin-walled fiberglass materials. The aim of this work was to perform tensile tests at room temperature in order to determine the stress-relative deformation dependence in selected directions and to compare the properties of each individual material in these directions. Characteristics determined in this way are to be used as inputs in simulation models forming a part of the process of validating the dummy model’s behaviour in simulations of collisions of the tram front with a pedestrian. Tests have been conducted of such properties of those materials used for external panelling of 15T and T3 tram fronts. The knowledge of these properties is crucial in terms of the mentioned validation. The output of the measurement includes tensile diagrams, including the evaluation of the ultimate tensile strength, elastic modulus and relative elongation at the ultimate tensile strength. Also, the conversion of the elastic modulus for the fibreglass with a different fibre volume part is presented.

This experiment assesses the suitability of square-welding high strength steel using the deep penetra-tion welding method, RapidWeld. The aim of this method suitability assessment was to compare the final material properties of three welds, welded accordingly to identical welding procedures. High strength, ultra-fine-grain steel S1100QL (XABO 1100) was used as a parent metal. The suitability con-firmation was based on the achievement of requested mechanical properties of ISO 15614-1 and mo-bile crane manufactures standards. The hardness, strength properties and impact energy measure-ment and evaluatioon of the joint was performed during the experiment. The joint was welded re-peatedly with the use of the same welding parameters for the confirmation of process stability. The achieved mechanical properties fulfill all the requirements. The hardness value deviation is caused by different properties in the heat affected zone. The root cause of the impact energy deviaton was not fully investigated, but the minimal measured values are above requirement. The deviation of the strength characteristics is mininal. The performed experiment has confirmed that the selected weld-ing method is suitable to ensure that the requested material properties of welded high strength, ultra-fine-grained steel are achieved.

Lighter and lighter products are required by aerospace and automotive sectors in order to reduce fuel cost and carbon dioxide emissions and, to allow using green energy propulsion, such as the electric one. In order to lighten parts aluminium alloys, which have a high strength to weight ratio, are the most commonly used metal materials. They are manufactured through plastic deformation processes often by using tailored blanks. This work focuses the attention on semi-finished products obtained by subtract-ing material through machining; they are a further class of tailored blanks. In this work, the design of a simple (almost hemispherical) aluminium alloy sheet component in AA2017 aluminium alloy is analysed, with the help of finite element analysis. In order to reduce the component weight; a circular blank was used, characterised by a variable initial profile of the thickness instead of the conventional disc with a constant initial thickness. Given that a more uniform final thickness profile is determined, enhanced resistance characteristics of the product component are achieved. Therefore, the workpiece will be characterized by a weight reduction of about 8% compared to the analogous ob-tained from a blank with a constant initial thickness.

Marine ships engines are kind of huge diesel engines. In fact, the manner of controlling the speed of a ship can impact badly on the financial matters of the machinery operation. Thus, controlling the speed of the marine engines can avoid ships to face dangerous accidents. In purpose to prevent such kind of damages, marine systems simulator have been widely used as numerical tools. In fact, the simulation of speed control systems makes it possible to render the process of controlling the speed of an engine economical and eliminates many risks. In this article, we first present a mathematical formulation to illustrate the rotational velocity process of a ship model's marine diesel engine as well as its PID controller. Secondly, we introduce a novel python's marine simulator which includes a PID controller to govern marine ship model's engines and we compare its results with another PID diesel engine speed controller that we modelled, designed and simulated via Matlab/Simulink. Results of scenarios and experiences which we carried out have shown that the response of the speed control system when using python can be accurate and close to the one of Matlab/Simulink.

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 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.

The work presents the computer simulation results describing the motion of the interacting particles in a vortex fluidized bed (the constrained motion). The data obtained reveal the peculiar features of the polydisperse system motion in the apparatuses with the variable cross-section of the workspace. The empirical coefficient determining the residence time of a particle in the vortex fluidized bed was calculated. An algorithm of the residence time cal-culations for a particle in the vortex fluidized bed under the constrained motion is developed. The results of com-puter simulation were a part of engineering (technological and constructive) algorithm of calculation for the fu-ture manufacturing of granulator?s industrial sample.

The experiments aimed to verify the use of a focused ion beam (FIB) to create structures analogous to the natural surface and then use the two-step imprinting method to prepare replicas of the surface creat-ed by FIB. The surface of the petal leaves of pansy (Viola x wittrockiana) was selected as a natural sur-face pattern. The TESCAN AMBER FIB-SEM microscope was used for the preparation of an analo-gous surface. The molds for the replication process were made of President Light Body elastomer. PVB, PVA, CMC, PCL, EP were used for the preparation of polymer replicas. Scanning electron micro-scope was used to evaluate the quality of the prepared polymer replicas. The dimensions of the replicat-ed convex and concave structures were 25 x 20 µm. The polymers showed a different ability to copy the structure in detail. For PVA, CMC, and PCL, surface structuring at the nanometer level was described in this study. Due to the dimensions of the cones of convex and concave structures, the color was ob-served on all samples.

The AGVs or mobile robots are well used in today’s manufacturing supply technologies and also can be used in engineering’s education. The motion controlling and simulation of such vehicles are a cru-cial question. This paper introduces the steps of motion planning for a driverless carrier vehicle from the positions initially available to the speed of the wheels. The vehicle is located in the High-Tech Logistics Systems Laboratory of the Logistics Institute of the University of Miskolc. For motion con-trolling and simulation between two points the further modules are necessary: 1. path planner, 2. tra-jectory planner, 3. velocity-voltage converter using velocities gained from trajectory planner, 4. mo-tion controlling and simulation of a motor dynamical model using voltages from the converter, 5. simulation of the path and 6. data processing. In this paper the first two modules are detailed, i.e. the path planning and then the trajectory planning. Path planning is based on a new approach, using Bezier-curves and Hermite curves. The trajectory planning tends to the mininum energy, which can be carried out by the examining the current consumption created in the other modules. The smaller consumption originated from the two curves determines the final path and trajectory.

The article compared the strength results of single-lap adhesive joints made of galvanized steel sheet. The strength of adhesive joints was determined for two methods of surface treatment - using a degreaser (method B) and with-out a degreaser (method A). The samples were joined using a two-component epoxy adhesive based on Bisphenol A. The strength tests were carried out on a Zwick/Roell Z150 testing machine. The analysis of the surface roughness parameters of the samples for the method A was performed. The highest shear strength value (8.82 MPa) was ob-tained by method B and using P120 abrasive paper. The lowest shear strength value (4.08 MPa) was received using method A and P600 abrasive paper. The maximum values of measured surface roughness parameters were rec-orded for samples prepared with abrasive papers with granulations, respectively: P120, P220 and P180. The low-est values of Ra, Rz and Rt parameters gained using P600 abrasive paper.

This paper describes series of studies concerned with welding of Sc-modified AA2519 at the Military University of Technology. The modification of AA2519 alloy contains a higher concentration of scandium and zirconium and it has been developed in The Institute of Non Ferrous Metals, Light Metals Division in Skawina. The examination involves friction stir welding (FSW) and laser beam welding (LBW) of 5 mm thick AA2519-T62 extrusion. FSW process parameters were: 600 rpm tool rotation speed, 100 mm/min welding velocity, 4.8 mm depth plunge, and MX Triflute tool type. The used LBW parameters were as follows: 3.2 kW laser power, 1.1 m/min welding velocity, 0.2 mm laser beam width, 10° laser beam inclination angle, 10 L/min shielding gas (argon) flow with the laser beam focused on the workpiece surface (f=0). In this work selected results have been presented containing some problems and features typical for investigated joints. Butt joints produced by FSW and LBW have been compared in terms of microstructure (grains), microhardness distribution, joint efficiency, localization of failure, etc. The basic features of weld zones have been discussed together with the distributions of microhardness on the joint’s cross-sections. Both welding techniques cause a reduction of microhardness in the weld zone, but the drop from the base material’s value (135-140 HV0.1) is far higher in the case of LBW (85-90 HV0.1) than FSW (120 HV0.1). The established values of joint efficiency were 80% (376 MPa) and 66% (314 MPa) for FSW and LBW, respectively. The FSW joints tend to fail in the thermo-mechanically affected zone and LBW in the fusion zone.

In the performed experiment, changes in the microstructure of steels S265 and X6CrNiTi18-10 due to their chemical-thermal treatment by boriding were studied. The boriding process was performed in a Durborid boriding powder at 900 0C. During this process, surface layers of Fe-B borides were formed in both analyzed sorts of steels. The layers differed in their morphology and composition due to the different degree of alloying of the matrix of analyzed steels by additive elements. The formed Fe-B layers showed high adhesive and cohesive resistance in both materials. Due to changes in the micro-structure of S265 steel, especially due to significant coarsening of the original grain of its matrix, its resistance to tribological abrasion after the boriding process decreased. The opposite effect was ob-served for X6CrNiTi18-10 steels. As a result of boriding, both analyzed materials changed their corro-sion resistance.

This paper deals with a synthesis of a new ionising radiation attenuation composite material from Lu2O3 - Bi2O3 nanoparticles structure, that has never been described yet. The paper describes the preparation of Lu2O3 - Bi2O3 nano- and microparticles by three methods: a self-combustion synthesis, a solid-state method and a coprecipitation method. Polymer solution was prepared from Lu2O3 - Bi2O3 nanoparticles and Polyvinyl Butyral. Afterwards, nanofibers were processed by an electrospinning method from PVB - Lu2O3 - Bi2O3 polymer solution. PVB - Lu2O3 - Bi2O3 nanofibers were characterised and their X-Ray attenuation effect was tested. This paper proceeds from one of the author’s bachelor thesis.

The article deals with the design of a robotic workplace for laser engraving. The first part of the article describes the importance of introducing robotics to industry 4.0. Custom solutions work is devoted to the implementation of the six-axis robotic arm UR10. This six-axis robotic arm inserts the designed jig with the semi-finished product into the engraving machine. In the engraving machine, the semi-finished product is engraved on the final product. This saves the operator time to pinpoint the position of the semi-finished product inside the engraving machine. The proposed jig is designed to be universal so that the position in the x-axis and in the y-axis can be precisely defined. At the end of the jig there is a bed for placing the semi-finished product, which can be replaced by another in the case of other dimen-sions of the semi-finished product. The conclusion is a comparison of time savings in individual steps and overall engraving time savings for one engraved part.

Measurement results on the Damping Loss Factor (DLF) and Coupling Loss Factor (CLF) between two steel plates is presented for 19 different junction types. The junctions involve joining technologies as line welding, point welding, bolting, riveting, gluing or their combinations, with parameters, such as spac-ing between the junction points or the angle between the plates varying. From the measurement results the DLF and CLF values were calculated by the Power Injection Method for the purposes of being ap-plied in Statistical Energy Analysis simulations. Four excitations were applied at each subsystem by impact hammer, while the response was recorded at sixteen response points at each subsystem. The measured CLF values were compared to each other from various aspects. Data were compared to the results obtained from SEA simulations by using the built-in analytical formulas. In general, good com-parison was observed, although the results appeared to be somewhat dependent on the frequency band. Finally, it was examined whether replacing the DLF values with data obtained for an uncoupled flat plate as well the CLF values with data from analytical formulas leads to acceptable accuracy of the re-sults.

The topic of the article is the increase of cutting conditions in the machining of heat-resistant steel using exchangeable inserts. The main part is the design of a new technology for machining one of the heat-resistant materials using replaceable inserts, including a discussion of any defects and economic evaluation. The aim is to reduce production costs and contribute to the elimination of production times. These modifications of technologies have a positive effect on the overall economy of produc-tion and the use of new methods in practice. Heat-resistant steels have found application in many branches of production, especially in the aerospace industry for jet engine components. Their specific properties need a more detailed examination of the optimal conditions for their processing.

In this work the influence of material type and sample fill density was evaluated. One PLA material was tested. Test specimens having different fill structure and density were printed from this material. Full honeycomb and gyroid shapes were used for the fill structure. The specimens had four different fill percentages for each structure: 10%, 25%, 50% and 75%. These bodies were compared to samples that were printed with 100% fill. Tensile test was performed on printed test pieces. The Zwick / Roell Z100 was used for testing and the surface hardness of the test specimens was measured by the Shore D method on a DIGI-Test II hardness tester. Fracture surfaces were evaluated on an Olympus DSX 500 optodigital microscope. The results showed that the shape of the fill did not signifi-cantly affect the values obtained by the tensile test. The hardness measurement results showed a different hardness on the bottom surface that was in contact with the printing pad and the top printing surface. Fractographic analysis revealed different types of fracture surfaces related to the printed fill structure.

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.