MODELLING STUDIES ON THE USE OF ALUMINIUM ALLOYS IN LIGHTWEIGHT LOAD-CARRYING CRANE STRUCTURES

Summary. The article presents the results of numerical analysis whose aim was to compare the basic dynamic and strength parameters of lightweight load-carrying crane structures made of aluminium alloys and steel. The analysis covered the typical construction of workshop cranes with a span of 3 to 5 meters, girders in the form of an I-beam and maximum load capacities amounting to 5 tons. The values of stresses, deflections and natural frequencies were compared and then matched with the masses of the various structures. In the simulation a girder model was used and computed by the finite element method

Modeling assumptions influence on stress and strain state in 450 t cranes hoisting winch construction

This work investigates the FEM simulation of stress and strain state of the selected trolley’s load-carrying structure with 450 tones hoisting capacity [1]. Computational loads were adopted as in standard PN-EN 13001-2. Model of trolley was built from several cooperating with each other (in contact) parts. The influence of model assumptions (simplification) in selected construction nodes to the value of maximum stress and strain with its area of occurrence was being analyzed. The aim of this study was to determine whether the simplification, which reduces the time required to prepare the model and perform calculations (e.g., rigid connection instead of contact) are substantially changing the characteristics of the model

"Movable platform" - the idea and energy consumption

This paper presents the application of the concept of moving sidewalks at railway stations (the movable platform) including the calculation of electricity consumption. Particular focus was placed on issue of energy profit and loss in two stages - through the loss (consumption) of energy by using a moving sidewalk at a railway station platform and the profit (reduced consumption) of energy, by the lack of having to start the train, that supports movable platform, from the initial speed of 0 km/h

Calculations of tramway track capacity in the wide area networks

The article shows a way of calculating the tram network capacity. A wide area network in Silesian Conurbation was used as an example (before and after planned modernization). Special attention was put on the traffic limiters like: single-track sections, stops, junctions, crossings with traffic lights, etc. Travel times and other characteristics were determined with the use of Monte Carlo method. In total, the capacity calculations of the tram network in Silesian Conurbation (divided into 74 sections) had taken into account: 131 crossings with traffic lights, 395 stops, 52 junctions, 51 single-track sections

Dynamic response of the spherical pendulum subjected to horizontal Lissajous excitation

This paper examines the oscillations of a spherical pendulum with horizontal Lissajous excitation. The pendulum has two degrees of freedom: a rotational angle defined in the horizontal plane and an inclination angle defined by the pendulum with respect to the vertical z axis. The results of numerical simulations are illustrated with the mathematical model in the form of multi-colored maps of the largest Lyapunov exponent. The graphical images of geometrical structures of the attractors placed on Poincaré cross sections are shown against the maps of the resolution density of the trajectory points passing through a control plane. Drawn for a steady-state, the graphical images of the trajectory of a tip mass are shown in a three-dimensional space. The obtained trajectories of the moving tip mass are referred to a constructed bifurcation diagram

Analysis of the Possibilities of Using VI Corridor of Transport for the Alternative Export of Bulk Cargo from Upper Silesia (Poland) to the Mediterranean Countries

The article assesses the possibility of activation of transport and logistics services in relation Silesia – Trieste - Alexandria and by continuation towards India. The increasing demand for transport on this route, where the section will be located onshore in the sixth (and part of fifth) transport corridor and the forecast of traffic on the route for transportation of bulk materials, justify launching intermodal connections there. It is expected that the market for transport in the analyzed route will have significant bulk loads (coal, coke) in the area of Silesia, in the direction to the south of Europe and further by maritime transport to customers in Egypt and India (coke plants, steel mills)

Application of electronic dental dynamometer in biomechanics

The paper presents a microprocessor force recorder, whose design allows the measurement of occlusal forces on a continuous basis with a maximum frequency of 250 Hz. The electronic dental dynamometer records the results of clinical trials in the form of graphic images and text files which are presented directly onto the computer. The recorded results can be processed digitally, as well as compared with other measurements, resulting in the ability to monitor the progress and potential advances in the treatment of masticatory organ diseases. An important advantage of the proposed solution is the simple and intuitive design. In addition, the dynamometer requires no power coming directly from the electricity network, as it is powered through a 5 V USB port. This feature not only determines the comfort of use, but also the safety as the voltage does not pose a risk to the patient during examination. The results recorded during clinical trials using the electronic dental dynamometer are consistent with those obtained using a calibrated mechanical dental dynamometer

INFLUENCE OF CHANGES IN THE WORKING TEMPERATURE OF FLEXIBLE COUPLINGS ON THEIR STIFFNESS CHARACTERISTICS

This article compares flexible couplings of the spider-type insert, and the tire-type insert. The influences of the volume and hardness of the elastomeric connector on the characteristics of this type of coupling, as well as the course of the change of the stiffness coefficient as a result of changes in the operating temperature, are presented. In drive systems, flexible couplings undergo very frequent changes within a wide range of operating temperatures, which causes a change in the dynamic parameters of the flexible couplings during operation