An article presents actual information about innovate welding technology with micro-jet cooling. There are put down information about gases that could be chosen for micro-jet process. There were given information about influence of various micro-jet gases on metallographic structure of steel welds.Keywords: welding, micro-jet cooling gases, weld, metallographic structure, acicular ferrite W artykule przedstawiono innowacyjną technologię spawania z chłodzeniem mikro-jetowym. Podano informacje nt gazów, które mogą być wybrane dla mikro-jetowego procesu. Uzyskano informacje o wpływie doboru gazu mikro-jetowego na strukturę metalograficzną stalowych spoin.

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An article presents information about innovate welding technology (surfacing) with micro-jet cooling. There are given main information about parameters of shaft surfacing with micro-jet cooling process. There were also put down information about influence of various micro-jet gases on metallographic structure of machine shaft after surfacing. There were tested tribological properties of welds. The tribological interactions of a solid shaft surfaces were tested after welding with micro-jet cooling.

Due to the development of the shared economy, increasingly more shared mobility providers have launched services based on the use of electric vehicles. The increasing growth of electric shared mobility services has produced various types of problems that do not occur (or occur with a limited effect) under conventional shared mobility systems. This increase in electric shared mobility problems has led to many effects, including limitations of the system zones or going out of business. To avoid difficulties in the functioning of electric shared mobility systems, various scientific studies have been undertaken to model and optimize the operation of these systems. Modeling and optimization mainly relate to one category of the system—for example, only to bike sharing. However, to understand the system of electric shared mobility holistically, there is a need to define the criteria generally as stimulants or destimulants. Based on these assumptions, we conducted research on the identification of factors influencing the development of electric shared mobility services. We conducted our own expert research based on the Social Network Analysis method. The aim of this study was to determine the factors that influence the development or recession of services in the entire electric shared mobility market in reference to selected stakeholders. The obtained results indicate a non-standard approach to the modeling and optimization of electric shared mobility services. This study could be used as support for creating electric shared mobility models and could also be helpful for service providers or local mobility managers through the developed recommendations.

The study discussed in the paper consisted in testing the impact of surface layer parameters on wear intensity of friction pair components. The study was conducted having taken additional operational factors into consideration, namely the friction conditions (presence of lubricant) and the value of loads affecting the contact zone of the samples being tested. The study constituted laboratory tests of wear and were conducted by means of a T-01M type laboratory test stand used to experimentally analyse frictional cooperation of various materials used in structural components of motor vehicles. The friction pairs examined were previously operating in a pin-on-disk system under various conditions. The materials of the friction pairs tested at the stand were subjected to heat treatment and chemical processing in order to attain specific parameters of their surface layers. The studies conducted enabled determination of the abrasive wear values for the material samples tested having entailed the surface layer parameters and the factors related to operation of actual structural components used in automotive engineering. An additional advantage of the studies conducted was the possibility to establish actual coefficients of friction occurring in specific friction pairs. Establishing the actual values of friction coefficients for the materials of friction pairs under specific conditions and having taken the impact of the surface layer parameters into consideration enabled identification of the reasons for excessive surface wear. Hence a reference can be made between the stationary tests undertaken and actual components cooperating with one another in kinematic pairs of machines. The utilitarian premise resulting from the studies conducted is the necessity of paying particular attention to surface layer parameters while designing friction pairs for machines.Keywords: surface layer, wear, friction coefficient W pracy badano wpływ parametrów warstwy wierzchniej na intensywność zużycia elementów pary ciernej. Badania przeprowadzono przy uwzględnieniu dodatkowych czynników eksploatacyjnych takich jak warunki tarcia (obecność środka smarnego) oraz wartość obciążeń w strefie kontaktowej badanych próbek. W ramach pracy przeprowadzono badania laboratoryjne zużycia przy wykorzystaniu stanowiska badawczego typu T-01M, na którym eksperymentalnie analizowano współpracę cierną różnych materiałów stosowanych na elementy konstrukcyjne pojazdów samochodowych. Badano pary cierne, które pracowały w układzie trzpień -tarcza w różnych warunkach. Materiały badanych na stanowisku par ciernych poddawano zabiegom cieplno-chemicznym w celu uzyskania określonych parametrów warstwy wierzchniej. Przeprowadzone badania umożliwiły wyznaczenie wielkości zużycia ściernego badanych próbek materiałów przy uwzględnieniu parametrów warstwy wierzchniej oraz czynników związanych z eksploatacją rzeczywistych elementów konstrukcyjnych wykorzystywanych w technice motoryzacyjnej. Dodatkowym atutem przeprowadzonych badań było wyznaczenie rzeczywistych współczynnikó...

Summary. The programing documents of the European Union determine the direction of transport systems development, including large cities and agglomerations. The context of these actions which aim to transform into ecologically clean and sustainable transport system is a significant reduction of greenhouse gas emissions. Assuming that public transport will significantly reduce the use of combustion-powered buses, studies on urban logistic enabling the use of electric buses for public transport are needed. The article presents the variants and scenarios for electric buses implementation in urban public transport, as well as the decision algorithm to support electric bus implementation based on technological, organisational, economic and ecological variables. TRANSPORT PUBLICZNY W AGLOMERACJACH Z WYKORZYSTANIEM AUTOBUSU ELEKTRYCZNEGO -TENDENCJE ROZWOJUStreszczenie. Dokumenty programowe Unii Europejskiej wytyczają kierunki rozwoju systemu transportowego także w dużych miastach i aglomeracjach. Kontekstem tych działań, mających na celu przemianę systemu transportowego w transport ekologiczny i zrównoważony, jest znaczące ograniczanie emisji gazów cieplarnianych. Zakładając, że w transporcie publicznym nastąpi znaczne ograniczenie wykorzystania autobusów z napędem spalinowym, niezbędne są badania nad logistyką miejską, umożliwiające wykorzystanie autobusów elektrycznych do transportu publicznego. W artykule przedstawiono warianty i scenariusze wdrażania autobusów elektrycznych w publicznym transporcie zbiorowym oraz zaprezentowano algorytm wsparcia decyzji na podstawie zmiennych technicznych, organizacyjnych, ekonomicznych i ekologicznych.

This article presents the results of investigating the influence of tooth contact ratio in helical cylindrical gears on vibroactivity of the gearbox. Based on the measurements carried out on a laboratory test stand, time-domain and frequency-domain start-up characteristics of vibrations and acoustic pressure were determined, and vibroactivity was assessed for a gearbox in which 4 pairs of gears were successively mounted with different face contact ratios equal to, respectively, ε β =1,001; 1,318; 1,574; 2,636.

Advanced high-strength steel (AHSS) steels are relatively not very well weldable because of the dominant martensitic structure with coarse ferrite and bainite. The utmost difficulty in welding these steels is their tendency to crack both in the heat affected zone (HAZ) and in weld. The significant disadvantage is that the strength of the welded joint is much lower in comparison to base material. Adopting the new technology regarding micro-jet cooling (MJC) after welding with micro-jet cooling could be the way to steer the microstructure of weld metal deposit. Welding with micro-jet cooling might be treated as a very promising welding S700MC steel process. Tensile and fatigue tests were mainly carried out as the main destructive experiments for examining the weld. Also bending probes, metallographic structure analysis, and some non-destructive measurements were performed. The welds were created using innovative technology by MAG welding with micro-jet cooling. The paper aims to verify the fatigue and tensile properties of the thin-walled S700MC steel structure after welding with various parameters of micro-cooling. For the first time, micro-jet cooling was used to weld S700MC steel in order to check the proper mechanical properties of the joint. The main results are processed in the form of the Wöhler’s S–N curves (alternating stress versus number cycles to failure).