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 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

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

The transcript of the discussion on the need to prepare a guide to distributed archival collections of the NSZZ "Solidarnosc"

Tekst jest zapisem (stenogramem) dyskusji na temat potrzeby opracowania przewodnika po rozproszonych zbiorach archiwalnych NSZZ "Solidarność", odbytej podczas konferencji naukowej w Gdańsku dnia 21 listopada 2013 r. w historycznej sali BHP w Stoczni Gdańskiej z udziałem ekspertów (archiwistów, bibliotekarzy, muzealników, historyków, praktyków i działaczy związkowych).The text is a record (transcript) of the discussion on the need to develop a guide to the distributed archive collections of NSZZ "Solidarność" (Independent Self-governing Trade Union "Solidarity"), held during a scholarly conference in Gdansk on November 21, 2013 in the historical OHS Room in the Gdańsk Shipyard with the participation of experts (archivists, librarians, museum professionals, historians, practitioners and trade union activists)