FEA Aspects of the Local Bending stresses at the HEA-section Runway Beams

This paper deals with the local bending stresses at the steel runway beams made of HEA sections. Some aspects of this structural problem are considered here, with usage of finite element analysis (FEA). There are presented three different models and several load cases to obtain the values of local bending stresses which enable the comparison with the results from adopted EN regulative. Specially, it is considered the possible superposition of stresses for adjacent wheel loads. This is done due to restriction in regulative which deals with the geometry of trolley vs. beam width. It is confirmed some inconsistencies in current regulative, along with the occurrence of affected zone in section with possible higher values of stresses near the web. Without consideration of volume, it is noted that distance of adjacent wheels has influence on the level of local stresses

Opracowanie metodyki oceny stanu technicznego lin kolei linowych o długim okresie eksploatacji /

Promotor: Andrzej Tytko.Niepublikowana praca doktorska.Praca doktorska. Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydział Inżynierii Mechanicznej i Robotyki. Katedra Transportu Linowego, 2015.Bibliogr. k. 165-170.Charakterystyka żywotności obiektów technicznych w ich procesie eksploatacyjnym, trwałość obiektów technicznych, trwałość ekonomiczna obiektów technicznych, czas bezawaryjnej pracy obiektów technicznych, okres żywotności kolei linowych i ich elementów, koleje linowe problematyka oceny bezpieczeństwa ich eksploatacji, podział elementów kolei linowych według wagi bezpieczeństwa, liny stalowe i zasady ich doboru w kolejach linowych, mocowania i zakończenia lin w kolejach linowych, zaploty lin stosowane w kolejach linowych, połączenia pojazdów kolei linowych z liną, wpływ pracy kolei linowych na żywotność pracujących lin, obciążenie lin kolei linowych, wpływ pracy kolei linowych na wydłużenie się lin, procesy zużyciowe lin i innych elementów pracujących w kolejach linowych, uszkodzenia lin stalowych, wpływ zmiany średnicy liny na zużycie lin stalowych, wpływ zmiany długości skoku liny na trwałość lin, nadzór i diagnostyka niezawodnościowa elementów kolei linowych, stan prawny oraz wymagania dotyczące diagnostyki elementów kolei, metody diagnostyczne, metoda wizualna badań lin stalowych VT, metoda magnetyczna badań lin stalowych MRT, interpretacja wyników badań magnetycznych, metoda radiograficzna, kryteria oceny lin kolei linowych, kryteria oceny stanu technicznego lin na podstawie wyników badań wizualnych, kryteria oceny lin na podstawie badań defektoskopowych, kryteria ekonomiczne odkładania lin, kryteria oceny zaplotów, urządzenie i metoda do pomiaru średnicy i długości skoku lin kolei linowych, urządzenie do pomiaru średnicy i długości skoku w technologii 2D, sposób realizacji pomiarów, opis wykonanych badań metodą 2D, opis wykonanych badań pomiarów cech geometrycznych, wpływ stanu powierzchni na wyniki badań, urządzenie do pomiaru średnicy i długości skoku pracujące w technologii 3D, ciągła rejestracja średnicy liny wiązka laserowa, metodyka postępowania przy badaniach lin kolei linowych, urządzenie do badań magnetyczno-wizualnych, określanie czasu kolejnego badania, gromadzenie danych z wyników badań diagnostycznych lin, ujednolicone zapisy dotyczące zużycia, korozja, starcia, pęknięcia i inne uszkodzeni

Steel ropes in machines opencast mining

Basic opencast mining machines belong to the group of devices used to perform specific technological operations through mining, loading, transport up to the dumping of mining heaps. Machines work in EBD systems (Excavator-Belt-Dumping) and require high reliability. Multi-bucket excavators that require the use of rope systems in order to maintain stability and the possibility of mining at different levels. The paper focuses on issues related to rope work in multi-buckets excavators. On the basis of studies to assess the technical condition of the ropes identifies the causes of damage to ropes these machines. As a result of the research, final conclusions were formulated

A tool for determining the number of bends and places of accumulation of potential wear of steel ropes operating in the luffing systems of basic opencast mining machines

This article presents the issues of the wear of steel ropes operating in the lowering systems of the largest wheel excavators (BWE), type SchRs, Rs, KWK operating in KWB Bełchatów. Sudden degradation of these ropes may lead to the complete shutdown of the BWE-Belt- Stacker system from operation. However, this can be avoided by regular visual inspections of hoist ropes. Unfortunately, the rope systems in each excavator are different, and their availability is difficult. In order to simplify this task, the authors of this paper have developed an IT tool that allows the modelling of a given multi-pulley rope system and the indication of critical places on the rope for given working conditions. A simplified description of this tool is the subject of the article

Some Stochastic Aspects of Safety Work of Steel Wire Ropes Used in Mining-Shaft Hoists

In most rope transport devices, the used steel wire ropes are replaced with new ones after working for a certain period of time, or after reaching the acceptable level of wear. The operational safety of the entire system depends on the correct diagnosis of the condition of the working wire rope. This is not easy, because the working lives of the ropes are varied, and their wear depends on many factors, including random ones. This article presents three different aspects of the work of steel ropes in mining-shaft hoists. What they have in common is a stochastic approach to interpreting the level of rope wear. The process of progressive wear due to fatigue breaking of wires is presented as the first example. This process is non-linear with a strong upward trend, which, in the final stage, turns into a phase often referred to as “explosive”. The rate at which subsequent wire breaks appear is influenced by numerous random factors, e.g., in the form of different methods and materials from which a given rope is constructed. However, the character of the progressing wear process is most affected by the random distribution of stresses experienced by individual wires and the randomly variable nature of the working environment. The second aspect presented in this article is an attempt to determine the probability of wire breaks of the rope. This was presented on the example of wear of the hoisting rope of a mining-shaft hoist. The last aspect of a stochastic nature, which is discussed in the article, is the issue of separating individual components of this distribution from the multimodal distribution describing the tensile strength of the rope wires, possibly of a normal character. Modern methods of analysis allow such distributions to be assigned to specific structural elements of the wire rope. This gives information about which structural elements of the rope wear faster or unusually and, consequently, determine its strength. This was presented on the basis of the results of strength tests of the wires of the mining-shaft hoist rope, which broke due to excessive corrosion wear of the inner strands. The presented examples explain only a short part of randomness in the description of working ropes, but the intention of the authors is to draw the attention of the personnel responsible for their safe operation to unavoidable random factors

Some aspects on quantification of the wear at steel wire ropes 10(th) International Conference on Tribology - BALKANTRIB '20 Belgrade, Serbia, 20-22 May 2021

Steel ropes are widely used in material handling machines. The excessive wear of wires is often presented as a type of rope degradation. One of many indicators of the wear is abrasion, corrosion and fatigue cracks. Within this class of rope degradation, the main representation of wear is wire abrasion in the layers of the external wires. This is especially noticeable at the steel ropes which are operating in the drum devices with multilayer winding and in hoists of mining shafts. Over performed work cycles, the estimation of losses in rope cross-section is important for the calculation of the rope capacity. Abrasive wear of external wires is a relatively easy phenomenon to detect with a qualitative interpretation. However, it is a very difficult phenomenon to quantify. The aim of this article is to address this issue. A brief survey of usual methods for rope inspections is given, which can serve as practical guidance for the engineers in this field. With accompanying case study, it presented the advantages of magnetic method in rope inspections oriented towards measuring the changes of wires within the wear assessment

Fatigue life of compacted wire ropes for applications in deep mining

Recent months have highlighted the progressing energy crisis across Europe in connection with the severe sanctions imposed on the import of hydrocarbons and coal from Russia. This is particularly visible in Poland, where over 40% of electricity is generated from coal, while in individual households it is the primary source of heat. This situation puts the already enigmatic plans of shutting down coal mining in Poland into question. Therefore, work aimed at increasing the extraction capacity of existing shafts while maintaining the highest level of operational safety is still valid. This article concerns the issues of the fatigue life of compacted ropes used as hoist ropes in mine shafts. The discussion regarding the use of these ropes among shaft hoist users has been going on for several years. This paper presents the unique results of compacted rope fatigue tests carried out at the Central Mining Institute in Katowice. In the authors’ view, these results and their interpretation should serve to clarify several important aspects that arouse the interest of users

Polymer Fibers Covered by Soft Multilayered Films for Sensing Applications in Composite Materials

This paper presents the possibility of applying a soft polymer coating by means of a layer-by-layer (LbL) technique to highly birefringent polymer optical fibers designed for laminating in composite materials. In contrast to optical fibers made of pure silica glass, polymer optical fibers are manufactured without a soft polymer coating. In typical sensor applications, the absence of a buffer coating is an advantage. However, highly birefringent polymer optical fibers laminated in a composite material are much more sensitive to temperature changes than polymer optical fibers in a free space as a result of the thermal expansion of the composite material. To prevent this, we have covered highly birefringent polymer optical fibers with a soft polymer coating of different thickness and measured the temperature sensitivity of each solution. The results obtained show that the undesired temperature sensitivity of the laminated optical fiber decreases as the thickness of the coating layer increases