Gabriel Fedorko

Computer modelling of wire strands and ropes part II: Finite element-based applications

In the comparison with the theoretical analyses of wire strands reported in the literature where obviously single-layered strands with a construction of the 1+6 wires were modelled and analysed, this paper is focused on a multi-layered strand with a construction of the 1+6+12+18 wires. The geometric parametric equations developed in the first part of this paper [1] are implemented in CATIA V5 software code for geometric modelling of the multi-layered strand. The methodology of their implementation and the approach for the generation of the strand geometric model are demonstrated. To predict the behaviour of the multi-layered strand under tensile loads, the mathematical geometric model is further implemented in a finite element program. For this purpose ABAQUS/Explicit software is used. The derived 3D geometric models of the multi-layered strands and the results of the finite element elastic behaviour analyses of the strand under tension loads are validated through comparisons with experimental and theoretical data available. The results obtained confirm the correctness of the derived parametric equations and mathematical and physical importance of the finite element model developed.

Computer modelling of wire strands and ropes Part I: Theory and computer implementation

In this paper the mathematical geometric models of the single-lay wire strands and double-lay wire ropes with defined initial parameters are presented. The present geometric models fully consider the single-helix configuration of individual wires in the strand and the double-helix configuration of individual wires within the wound strands of the ropes. The mathematical representation of the single and double helixes is in form of parametric equations with variable input parameters which determine the centreline of an arbitrary circular wire of the right hand lay and left hand lay strands and ropes of the Lang lay and regular lay construction. The concrete forms of the parametric equations are derived and presented. The application of the derived geometric analytical model is illustrated by numerical examples. Techniques for the implementation of the derived mathematical models in CATIA V5 software and procedures for the generation of the rope model are briefly presented. Correctness of the derived parametric equations and a performance of the generated rope model are controlled by visualizations. The application of the derived mathematical model and the development of a finite element model for the numerical simulation of the multi-layered strand under tension tests are treated in the second part of the paper [1].

Finite element analysis of spiral strands with different shapes subjected to axial loads

A new mathematical geometric model of spiral oval wire strands is proposed.Concrete forms of derived parametric geometric equations are presented.Results of FE analyses of four spiral strands with different shapes are presented.Responses of round, triangular and oval strands under axial loads are compared.Result ant stress and/or deformation behaviours are discussed. In this paper a new mathematical geometric model of spiral one or two-layered oval wire strands are proposed and an accurate computational two-layered oval strand 3D solid model, which is used for a finite element analysis, is presented. The three dimensional curve geometry of wires axes in the individual layers of the oval strand consists of straight linear and helical segments. The present geometric model fully considers the spatial configuration of individual wires in the right and left hand lay strand. Derived geometric equations were used for the generation of accurate 3D geometric and computational models for different types of strands. This study develops 3D finite element models of two-layer spiral round, triangular and oval strands subjected to axial loads using ABAQUS/Explicit software. Accurate modelling and understanding of their mechanical behaviour is complicated due to the complex contact interactions and conditions that exist between individual spirally wound wires. Comparisons of predicted responses for the strands with different shapes and constructions are presented. Resultant stress and/or deformation behaviours are discussed.

The Use of Computer Simulation Methods to Reach Data for Economic Analysis of Automated Logistic Systems

Abstract Automated logistic systems are becoming more widely used within enterprise logistics processes. Their main advantage is that they allow increasing the efficiency and reliability of logistics processes. In terms of evaluating their effectiveness, it is necessary to take into account the economic aspect of the entire process. However, many users ignore and underestimate this area,which is not correct. One of the reasons why the economic aspect is overlooked is the fact that obtaining information for such an analysis is not easy. The aim of this paper is to present the possibilities of computer simulation methods for obtaining data for full-scale economic analysis implementation.

The Simulation Model of Experimental Equipment for the Research of Pipe Conveyor Belts Using ABAQUS Software

We can effectively use experimental and simulation approaches for pipe conveyors research. The paper describes a simulation of experimental measurement which was realized by special test device for pipe conveyors research. The simulation model was created by the help of program Abaqus.

Regression Model Design for the Prediction of Pipe Conveyor Belt Contact Forces on Idler Rollers by Experimental Tests

In this paper there is presented a possibility to estimate, with a sufficient accuracy, contact forces on idler rollers of hexagonal idler housing in case of the pipe conveyor belt. This prediction is based on values of tension forces that are measured experimentally. The calculated regressive models are able to predict contact forces in individual positions of idler rollers with suitable correctness. The measurements of tension forces were carried out on a static model of a pipe conveyor. This static model is able to simulate real operational conditions of idler rollers, which guide the conveyor belt. In this way it is very simply possible to determine contact force values in the individual positions of idler rollers. Information about contact forces is useful for designers and for users of the conveyor belts, as well.

Numerical Analysis of the Influence of Material Model on Response of Compressed Imperfect Thin-Walled Channel

In the paper, the influence of material model selection on the behaviour of Finite Element model of a compressed thin-walled channel is studied. Results of three material models of channels of two different lengths and two types of geometric imperfections are compared and discussed.

Failure analysis of conveyor belt samples under tensile load

This paper is dedicated to investigating the properties of smooth conveyor belts through a tensile loading test, with the aim of examining the behavior of the inner structure of the belt samples. When the belt is subjected to a long-term strain, the belt relaxation effect is observed and changes may occur to the inner structure of the belt. The tensile test at constant velocity determines the load strength limit of the strip samples. The experiment has also shown the phenomenon of relaxation of the samples after the load. Metro-tomographic analysis is used to observe the behavior of the internal structure of the belt sample after the load. The obtained results indicate the initial damage of the inner structure of the conveyor belt occurred at the value of 2157 N. Under this load, the maximum damage size was 4.8 mm. This confirms the suitability of the method for tracking changes in the internal structure.

Analysis of defects in carcass of rubber–textile conveyor belts using metrotomography:

Rubber–textile construction of conveyor belts is widely used in various continuous transport systems. Due to the fact that complex carcass is vulcanised, its observation and analysis are very difficult to perform. The methods used so far have been based on its violent extracting, often accompanied with the formation and existence of defects. Such an analysis does not allow distinguishing between defects caused by operation of the belt or defects caused by the process of extracting itself. This paper aims to verify a new approach to examining the inner carcass of rubber–textile conveyor belts with a focus on the possibility to obtain information about its condition. This has not been possible with the methods used so far. The main focus is on the measurement of distance between the individual fibres in the warp and weft of the carcass, and simple size analysis of the identified defects. Presented results prove that the method of industrial tomography clearly identifies the defects in the conveyor belt carcass. The method enables the identification of single fibres, punctures and separation of individual layers.

Supplying of Assembly Lines Using Train of Trucks

Abstract The typical supply system conceptions, i.e. the concepts “Just-in-time” (JIT) and “Just-in-sequence” (JIS) are very important factors with regard to a fluent operation of the assembly lines. Therefore the contemporary intra plant transport systems are being replaced by a new kind of the transportation technology, namely by means of the trains of trucks. The trains of trucks are used in two possible operational modes: either with a driver or without driver (fully automated). The trucks of the logistic trains are also cheaper and they are able to carry a larger volume and mass of the material at once. There are reduced in this way not only the investment costs, but also the operational expenses.