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The scientific objective of the conducted experimental research was to find an answer as to whether the application of magnetic flux leakage would be an effective tool for assessing the technical condition of lift guide rails in which the loss of thickness of the guide part is damage resulting from the brake whose operation destructively affects the surface shown. In particular, the scientific objective was to investigate the potential of this method in the context of quantitative assessment of the degree of damage featuring small increments in depth at the level of tenths of a millimetre. The conducted research was also aimed at determining the correlation of the effect of damage type with the nature of the signal recorded. The article presents the results of our own research, obtained from experiments on the use of magnetic flux leakage (MFL) to diagnose damage occurring on lift guide rails. During operation, lift guide rails are exposed to contact with the friction elements of brakes, resulting in the violation of their surfaces. Damage to the working surfaces of guide rails increases the vibration of the device, noise and wear of other components of the lift, such as guide rails. Currently, diagnostics of lift guide rails are not carried out, and their replacement depends on their technical condition. However, from an economic point of view, there are situations wherein their condition allows their use without their replacement with new ones. This was the main factor that guided the authors; we used a diagnostic head of our own design for the tests. The obtained measurement results showed that magnetic flux leakage can be used with great success to diagnose damage to guide rails. The results obtained in the laboratory shall be further developed in the form of research on correlating the signals obtained from magnetic sensors and the size of the damage, which shall eventually allow for a final quantitative assessment of guide rails regarding their technical condition. The conducted research fits into the scope of sustainable development by reducing the need for the consumption of electric energy and the emission of harmful substances into the atmosphere in the overall production balance. This will be made possible by implementing the developed head in industrial practice in the context of assessing the need to replace guide rails with new ones. The economic and environmental efficiency that is the basis of sustainable development in the context of lifts can be achieved at the modernisation stage by repeated (further) use of as many components as possible. An example of this is the guide rail system, the reuse of which is possible after a prior assessment of its wear and tear.

The paper presents comparative laboratory investigations of tension fastener models that attach rails to concrete sleepers. The aim of the paper was to assess the influence of geometric nonconformity of the actual industrial product that meets the PKP Polskie Linie Kolejowe S.A. requirements on the operation of a tension-fastening clamp under stress. Due to the cost and limited possibility of research of the actual industrial product, an additional objective of the research was to validate the usefulness of it in the comparative assessment of the models. In the research, the authors used models of tension fastening clamps manufactured in incremental engineering technology (3D print) on scale 1:2. The properties of the fastening clamps (in their nominal shape) were compared (described in the PKP Polskie Linie Kolejowe S.A. documentation) with the fastening clamps of the actual shape. In the investigation, the authors have confirmed the negative influence of the non-conformance of the shape of the actual fastening clamps with the nominal ones.

The paper describes the process of a prototype head optimisation for magnetic diagnostics of steel-polyurethane load-carrying belts. The prototype, validated on a number of cranes, was subject to an improvement and optimisation attempt using numerical analysis of magnetic field distribution in the magnetic circuit, tested load-carrying belt, and environment. The analysis was carried out in the ANSYS environment using PDS—Probabilistic Design System tools (DOE—Design of Experiment). Taking the dimensions of individual elements of the magnetic circuit, material densities, and magnetic material properties as the input data, the magnetic circuit was optimised with respect to metrological properties as well as mass and size criteria. Based on the analyses carried out and the results obtained, the head design was modernised, which involved changing the geometry of elements forming the magnetic circuit. Based on observations made during tests of the prototype version of the device performed on real objects, several improvements were also proposed, consisting of the replacement of selected components with elements printed in the FDM technology. The correctness of the performed numerical analyses was verified by comparing the measured and calculated values of the total magnetic field induction in the defined plane of the magnetic circuit. The prototype versions of heads before and after modernisation were subject to comparative tests. Under laboratory conditions, both versions of heads were used to diagnose the steel-polyurethane load-carrying belts with modelled damages. The obtained test results and their statistical characteristics were analysed in detail.

This study discusses a quantitative fatigue evaluation of polymer–ceramic composites for dental restorations, i.e., commercial (Filtek Z550) and experimental Ex-nano (G), Ex-flow (G). Their evaluation is based on the following descriptors: mechanical strength, elastic modulus and strain work to fracture. Supposed to reflect factors of environmental degradation conditions, thermal fatigue was simulated with a special computer-controlled device performing algorithms of thermocycling. The specimens intended for the strength test underwent 104 hydro-thermal fatigue cycles. This procedure of thermocycling was preceded by aging, which meant immersing the specimens in artificial saliva at 37 °C for 30 days. The strength tests after aging only and after aging and thermocycles were performed in line with the three-point flexural strength (TFS) test, specified in ISO 4049, and the biaxial flexural strength (BFS) test, specifically piston-on-three-ball in accordance with ISO 6872. Based on the results, it can be stated that composites with higher volume content of inorganic particles after aging only show higher strength than materials with lower filler particle content. For example, the average flexural bending strength of the Ex-flow (G) composite was about 45% lower than the value obtained for the Ex-nano (G) material. The residual strength after thermocycles is significantly lower for the experimental composites, whereas a smaller decrease in strength is recorded for the commercial composites. Decreases in strength were about 4% (Filtek Z550), 43% (Ex-nano (G)), and 29% (Ex-flow (G)) for the BFS test; and about 17% (Filtek Z550), 55% (Ex-nano (G)), 60% (Ex-flow (G)) for the TFS test. The elastic modulus of the experimental composites after only aging is higher (about 42%) than that of the commercial composite, but the elastic modulus of the commercial composite increases significantly after thermocycling. A descriptor known as strain work to fracture turns out to be a good descriptor for evaluating the hydro-thermal fatigue of the tested polymer–ceramic composites.

This article discusses current testing methods for motor vehicle engines. Traction engines have so far been tested, for example, according to WLTP (Worldwide Harmonized Light Vehicle Test Procedure) driving tests, but due to the “VW—gate” incident, these are now to be supplemented by RDE (Real Driving Emissions) tests, conducted under real road conditions. The analyses of the state of knowledge and the directions of research to date unequivocally indicate the need for the construction of a stand that allows: testing of a complete vehicle admitted to traffic; testing of a motor vehicle with the possibility of simulating real operating conditions; load setting with the possibility of its regulation; feeding the engine with various fuels; modification of the software of controllers having a direct impact on the control strategies of the engine; transmission and traction control system; reading, recording and analysis of the parameters of the operation of control systems in real time; detailed recording and analysis of the combustion process occurring directly in the combustion chamber; and the measurement of emitted toxic substances. On a bench with the above features, tests were carried out on a diesel motor vehicle, which were based on recording changes in the parameters of the combustion and injection process. The tests were conducted under static and dynamic conditions. Tests under static conditions were conducted on a chassis dynamometer. They consisted of indicating the engine for different fuel dose control maps. The vehicle equipped with the test engine was driven at a constant speed on the chassis dynamometer and loaded with a drag force of 130 Nm. Tests under dynamic conditions were conducted under real traffic conditions. They were limited to the presentation of results under static conditions. The main results of the tests are given in the conclusion and include a general summary. In particular, the presented results of the diesel tests demonstrate an attempt to adapt the engine to co-power with hydrogen.

It is a quite common practice to place the load at some distance from the machine restraint. In such a case, it is possible to evaluate the values of stresses and displacements by means of numerical analyses. This article presents the numerical analysis results for the carrying structure of the friction lift power unit with the use of the remote load. The impact of the remote load on the strain of the lift power unit carrying structure is also described. Attention is paid to the places of excessive strain of the structure.

This article presents the results of the structure optimization for the power unit carrying frame of a friction lift by means of numerical calculations using the finite element method (FEM). Optimization analysis covered the frame structure. The analysis was focused on strength optimization with the use of a remote load and on manufacturing optimization with attention paid to the operating times necessary to complete the production process of the carrying frame subassemblies. The Solidworks simulation program was used to optimize the frame in terms of the strength criterion. The program allowed both quantitative and qualitative assessments of the frame material effort before and after optimization.

This paper deals with nonlinear mechanics of an elevator brake system subjected to uncertainties. A deterministic model that relates the braking force with uncertain parameters is deduced from mechanical equilibrium conditions. In order to take into account parameters variabilities, a parametric probabilistic approach is employed. In this stochastic formalism, the uncertain parameters are modeled as random variables, with distributions specified by the maximum entropy principle. The uncertainties are propagated by the Monte Carlo method, which provides a detailed statistical characterization of the response. This work still considers the optimum design of the brake system, formulating and solving nonlinear optimization problems, with and without the uncertainties effects.