bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methods of enlarging material to the concentration table
Authors: Feliks Jacek , Krawczyk Magdalena 
Published: November 2019

Abstract
Concentration tables are one of the oldest oscillatory enrichments with over 100 years of tradition. On this type of distribution tables are made according to material mass in many recurring cycles induced by appropriate drives. So-called wet tables are the devices most often used for coal enrichment in Polish mines because this process generates very high costs, high water consumption and pollution of the environment, as well as the need for, among others, water and mud management is increasingly being replaced mainly in areas poor in water by the modern model of the air concentration table – FGX produced in China. The process of enrichment on this type of table itself runs in a manner comparable to the method of wet enrichment with the difference that the FGX is distributed on a perforated plate, in this case we deal with air pollution. Department of Machinery Engineering and Transport's attempts to use the differences in coefficients of friction in over-resonance screens have shown that it is possible effective separation of grains with different coefficients of friction. The article presents a theoretical analysis and presents the results of performed dry enrichment trials using different coefficients of friction. The summary presents the advantages of using the enrichment method using the differences in friction coefficients and test results.
Modified ground support with alternative fill material for ground control at munsar underground manganese mine of moil limited, India
Authors: Manekar Ganesh , Shome Dipankar , Chaudhari Mukund 
Published: November 2019

Abstract
MOIL Limited is operating 7 underground and 3 opencast mines in central India and producing annually more than 1.3 million tonnes of various grades of manganese ore. The underground mines are operating at shallow – 90 m at Munsar mine to moderate – 353 m at Balaghat mine below the surface with horizontal cut and fill (HCF) or its variant method of stoping with post filling by hydraulic sand stowing. The Munsar mine is being worked underground since 1903. The opencast mining is presently stopped. The ore body below the opencast quarry is geological continuity of the area excavated in past by opencast method of mining. The underground mining is done through the adit in three levels i.e. 270’L, 220’L, 170’L and by incline in western part of the property at 70’L. The horizontal drift development has been developed in the manganese ore body with sill drive of 5 m above the sill pillar in lower level at 70’L and barrier pillar of 5 m thickness is left for protection of upper level at 170’L. Valuable mineral has been locked in sill pillar and therefore rock mechanics investigations have been carried out. On the basis of study now the drift development has been carried out in footwall rock at 70’L, (-) 30’L and below levels and it has improved the minable manganese ore by about 20%. In this modified HCF stope design, an alternative fill material in place of sand, which has been developed in house by use of overburden (OB) material after treatment, has been used for hydraulic stowing. The experimental trials find out that the alternative fill material of OB is more compact and forms a non-expansion floor for the men and machines in the stope. This will certainly help in the introduction of mobile underground mining equipment for drilling in the stopes and mechanical mucking, transportation and loading of the ROM. The paper presents rock mechanics investigations and future use of alternative fill material of overburden material after heat treatment for better safety and productivity at Munsar Mine of MOIL.
Functional structure of battery drive for self-propelled mining rig used in room-pillar ore exploitation system
Authors: Szurlej Tomasz , Ostapów Lesław , Mendyka Paweł 
Published: November 2019

Abstract
The article presents the structure of the battery drive of a self-propelled mining vehicle on the example of a drilling rig, used in the room-pillar system of copper ore exploitation. Such solutions, due to the ore mining in increasingly difficult operating conditions, are becoming more and more popular in the world. The main assumptions required for the synthesis of this type of drive were indicated, as well as the adopted structure of such a solution was described. The selection of the appropriate drive structure determines the final work characteristics of the self-propelled mining vehicle, and thus the actual suitability of such a machine for use in mining conditions. The paper also details the main technological advantages of this type of drive over classic internal combustion drives.
Simulation of the frequency response of the ERC 1400 Bucket Wheel Excavator boom, during the excavation process
Authors: Popescu Florin Dumitru , Radu Sorin Mihai , Andraș Andrei , Kertesz Brînaș Ildiko 
Published: November 2019

Abstract
The paper deals with the modal analysis and frequency response analysis of a bucket wheel excavator (BWE) boom, obtained by simulation, based on a virtual model of an existing BWE boom. The boom, which generally is realized as a spatial truss, is the most vulnerable subsystem of the BWE, being submitted to severe operational loads characterized by very pronounced cyclical, dynamic and stochastic variability. This vulnerability is the consequence of its shape and constructive parameters and the nature, source and character of the external exciting loads to which it is exposed. The classical approach recommended by standards and norms cannot predict the occurrence of failures caused by vibration, which produces fatigue due to the load’s cyclical variability and the deformation produced by resonant vibration of some constitutive elements. As exciting load we considered the operational forces acting on the bucket wheel. In this manner we can take into account the constructive features – with modal analysis, and the vibration regime – with frequency response analysis. The proposed method is useful both in the design phase of new load-bearing structures of truss type subjected to high-variability forces, and also in refurbishment or improvement phases of the existing structures of this kind.
The use of flat steel-polymer supporting ropes in mining multi-pole hoisting devices
Authors: Stawowiak Michał , Żołnierz Marcel , Rożenek Zenon 
Published: November 2019

Abstract
The paper presents the development of a series of flat steel and polymer bearing ropes using a polyurethane polymeric material (the name of NPSP – flat steel-polyurethane). These ropes are intended for mining extraction devices with friction drive (multi-mill drive wheel, multi-rope drums with a number of ropes from 3 to 12 pieces). The authors of this article have presented a comparison of the drive power of a selected multi-mine mine hoist device with a classic steel round rope with the same extractor in which steel and polymer flat carrying ropes were used. The article also presents the development of mining construction of hoisting equipment, which includes the use of new rope ropes. Very positive results from exploitation in Polish mining of flat steel-rubber balance ropes (durability up to 12 years) can be the basis for the use of such ropes as supporting ropes. Flat steel-polymer supporting ropes, in which the matrix can be rubber or polyurethane or other plastic material, could contribute to increasing the durability of load-bearing ropes due to anti-corrosion protection as well as to reduce the dimensions of drive wheels and rope hoisting machines, and thus to lower the power of the winding machine (as a result of reducing the moments of inertia of the propeller, propulsion and rope). It is also worth mentioning that the NPSP carrying ropes can work directly on steel coatings of propeller drums with proper positioning, created by clamping elements (wood, plastic or aluminum blocks).
Fem stress analysis of a barrel reamer
Authors: Baksa Attila , Ladányi Gábor , Szirbik Sándor , Virág Zoltán 
Published: November 2019

Abstract
Horizontal Directional Drilling (HDD) is a method of installing underground pipelines, cables and service conduit through trenchless methods. The tools and techniques used in the HDD process are an outgrowth of the oil well drilling industry, too. Installation of a pipeline by HDD is a three stages process. The first stage consists of directionally drilling a small diameter pilot hole along a designed directional path. Drilling fluid is pumped through the drill pipe to the drill bit where high pressure jets and the bit will grind the soils ahead of the drill stem. The second stage involves enlarging this pilot hole to a diameter suitable for installation of the pipeline. A reamer is pulled back and rotated while pumping drilling fluid to cut and remove solids to enlarge the hole. A kind of reamer is the subject of this paper. The final stage consists of pulling the pipeline back into the pre-reamed hole. The most important part of the mechanical analysis is to define the boundary conditions for operating situations when the tool is under maximum load. In this paper we present a helpful description for giving boundary conditions to perform the numerical simulation of a barrel reamer.
Modified calculation model for loads of bearing systems for tricone roller bits
Authors: Kipczak Piotr , Władzielczyk Krzysztof , Dudek Rafał 
Published: November 2019

Abstract
The article presents a modified calculation model of loads of cone bearing systems in tricone roller bits. The presented model includes the actual nature of the loads of a tricone roller bit and the effect of these loads on the construction of individual elements of the cone bearing systems. The presented calculation model was created in order to develop a computer program that allows the calculation and verification of structural parameters of cone bearing systems even at the stage of their initial design. It will allow an optimal selection of these parameters to geological properties of drilled rocks.
The use of simulation modeling in the design of elements of annular preventers
Authors: Dzhus Andriy , Romanyshyn Liubomyr , Mykhailiuk Vasyl , Mosora Yurii 
Published: November 2019

Abstract
One of the main elements of control over wells in the process of their construction is the blowout equipment, which includes annular preventers. This also applies to wells that provide degassing of coal veins to reduce their gas dynamic activity. Modern technology of work requires expansion of the functionality of the sealing unit of the annular preventers with the simultaneous provision of its operational characteristics. Determining the necessary durability of seals for different operating modes is the study of their stress-strain state. The paper deals with the possibility of using simulation modeling in the annular preventers design situations and within the study of the armature geometry influence of the sealant fittings on its stress-strain state. The method of determining the material constants to realize the Mooney-Rivlin model has been proposed. The behavior of low-density rubber in software product has been described by the finite element method. The aggregation error of experimental and theoretical studies is 5%. Therefore, the preconditions and the possibility of using simulation modeling in the design of annular preventers devices with increased operational characteristics have been created and confirmed.
Modeling the movement of broadcast on the concentration table
Authors: Feliks Jacek , Krawczyk Magdalena 
Published: November 2019

Abstract
The article attempts to analyze the work of the concentration table, on which the distribution of the material under investigation takes place. The efficiency of separation or otherwise enrichment depends on the drive that puts the concentration table plate into an asymmetrical reciprocating movement. The most frequently used solutions are concentration tables, on which the distribution of enriched material takes place in an aqueous medium commonly called wet enrichment. The AGH University of Science and Technology conducted simulation tests of material enrichment on a concentration table using the differences in friction coefficient commonly referred to as dry enrichment, i.e. without an additional medium. The article presents the effects of simulations that have been carried out for reference materials characterized by different friction coefficients and densities. The summary presents the analysis of obtained effects of computer simulations of material movement with different coefficients of friction. The simulations were carried out for variables: the frequency of vibrations of the concentration table and the angle of inclination of the table of the concentration table. It has been shown that it is possible to enrich the material by changing the above-mentioned operating parameters of the device.
Application of friction braking devices in drum shaft hoists
Authors: Rokita Tomasz 
Published: November 2019

Abstract
This article presents the problem of emergency braking in mining shaft hoists equipped with drum. The industrial applications of friction devices and mobile fender beams concerned only friction shaft hoists. For drum devices, it is necessary to use braking devices both in the shaft tower and its sump. The impact of such a solution on the construction of braking devices and on the braking process itself is the subject of the paper.
Systems of grained materials automated sampling from belt conveyors
Authors: Sidor Jan , Nawrocki Marcin 
Published: November 2019

Abstract
The collection of representative samples of grained materials is necessary to determine the quality parameters of this material. This operation is carried out in difficult conditions (dustiness, noise, atmospheric precipitation), which is a nuisance to the staff taking samples and adversely affects accuracy. In addition, the quality of representative samples is affected by the care of personnel. Therefore, to ensure a higher quality of sampling operations and to eliminate the work of people in difficult conditions, systems have been developed for the automatic collection of representative samples from conveyor belts. The work gives examples of automatic sampling systems equipped with samplers and other auxiliary devices. The work contains descriptions of construction, classifications, an example of selection and examples of construction solutions for automatic sampling of grained materials.
Research on the coefficient of friction of becorit K22 and K25SB linings
Authors: Stawowiak Michał , Żołnierz Marcel , Rożenek Zenon 
Published: November 2019

Abstract
The article presents the method and results of experimental tests of the coefficient of friction between a steel rope and friction lining. The BECORIT K22 and BECORIT K25SB floor coverings were tested. The tests were carried out in accordance with the recommendations of the new German standard: DIN 21258 – Lubricants and impregnating agents for drive discs and transport ropes in mining – safety and testing requirements. The authors in this article emphasize that the Becorit K22 and K25SB linings are used for the wheels of propeller drums of mining machines. Characterized by high coefficients of friction (μ ≥ 0.25), also in cases of extreme weather conditions on the surface. The chemical properties of BECORIT linings ensure their resistance to swelling in the event of different oils and lubricants as well as mine waters. The material of which the claddings are made ensures very good machinability during rolling of rope grooves with the use of turning or milling tools. BECORIT K22 plastic cladding is particularly suitable for use in hoisting machines, where the rope base forms a large overlap angle on the wheel grooves (max 1°31'), which causes its lateral wear faster. BECORIT K22 material in this case provides a higher service life compared to other materials. Due to the way they are mounted on the wheel, they are made as 1-piece (monolith) or bipartite. In this article, moreover, the structure and principle of operation of the measuring station on which the tests were carried out are presented in great detail.
The effect of temperature on the mechanical properties and workability of rock salt
Authors: Małkowski Piotr , Bednarek Łukasz , Kotwica Krzysztof , Stopka Grzegorz 
Published: November 2019

Abstract
Underground salt mining accounts for about 16 percent of the total salt production worldwide. When excavating salt rock, the cutters of the road header come into contact with the rock. This produces friction and, consequently, a rise in temperature. Generally, as temperature increases, salt gradually loses its plasticity. The extent of these alterations depends on the presence of other minerals in the rock. This paper presents the results of laboratory tests on regularly shaped samples of salt. An analysis was performed of the results of compressive, tensile and induced-shear strength, and of Young's modulus, Poisson's ratio, cuttability index and side chipping angle. The testing was conducted on samples with a temperature of about 20°C and samples heated to 50°C and 80°C. The tests showed that as temperature increased, so did compressive and tensile strength, and longitudinal and transverse strain of salt. The temperature increase caused, however, a decrease in shear strength. The cuttability index and the side chipping angle also decreased when the heated samples were being cut. The percentage changes in the parameters within the 60-degree temperature range were as high as several dozen percent.
Effective utilization of man shift through sustainable workload testing for underground mining machine operators. An ergonomic based man-machine interface approach
Authors: Dey Netai Chandra , Dey Shibaji 
Published: November 2019

Abstract
Insight of man-machine interfaces during mining machine operations, better co-ordinance with human efficiencies and suitable workload selection in underground mining machine operation are the main viewpoints of the study. Total 12 side discharge loader (SDL) and load haul dumper (LHD) operators [N = 12] have been taken as participants of the study. The methodology is divided into two parts first part is devoted to measuring and analyzing workload response of machine operation with polar heart rate monitor. Machine operator’s heart rate ratio (HR ratio) for the whole shift is recorded and metabolic rate (MR) has been analyzed. Additionally, fatigue sustainability (FS) and degradation of muscle force (MF) are recorded for each work cycles up to exposure time period (ETP) of 360 minutes. In the second part of the methodology, based on the HR ratio recorded during the mining operation, a workload simulation study is undertaken on a treadmill at the surface following BRUCE protocol. At treadmill, based on HR ratio, workload achieved from mines along with three different workloads i.e. low, moderate and high has been tested. Differences in FS and degradation rate of MF after each workload experiment have been recorded. A result from the underground operational study shows that there is about 43.2% and 32.4% of decreasing MF for SDL and LHD operators after end of spells at mines. Additionally, a negative correlation (r = −0.99) is found between ETP and MF. The workload simulation study shows that there are significant differences between FS (p < 0.05) and MF (p < 0.05) data of mining and treadmill experiment with the same workload. In comparison to an underground operation, FS rate of low, moderate and high workload is recorded 60%, 35%, and 15% higher respectively than of mine workload. Higher FS rate may achieve due to availability of good environment. Among the tested workload only low kind of workload is found suitable for mining machinery job as degradation of MF is found significantly (p < 0.05) low and FS is found significantly (p < 0.01) high in this kind of workload. Therefore, it can be concluded that in mining machinery operation better to adopt low workload for effective utilization of man shift (EUMS) as it gives comparatively low MF degradation and better FS during continuous work.
The strength problems in the operation of drum hoist cages
Authors: Wolny Stanisław , Matachowski Filip , Drzewosz Agata 
Published: November 2019

Abstract
From information obtained from periodic surveys of cages used in the shaft of one of the Polish mines, it appears that the majority of registered damages of their supporting elements are fatigue cracks. These cracks are formed and develop mainly in main nodes or welds in the areas of their connection with the construction of the cage. In order to eliminate the causes of these damages and to increase the durability of cages, it will probably be necessary to reconstruct those fragments of the cages in which they occur. In order to determine loadings of load-bearing elements and the state of stress that arises in them during the operation of the device, a numerical model of the cage was developed. The results of the calculations made as well as their analysis form the basis for the assessment of the strength and durability of the load-bearing elements of the discussed cage. The key problem determining the durability of the structure – as shown by the analyzes carried out – is the method of constructing the connection of the strings with the appropriate elements of the cage. Changing this state requires significant structural changes of these nodes, which the authors of this study pointed out.
X-Ray CT inspection of subsurface areas of concretes exposed to fast flowing liquids
Authors: Sitek Libor , Hlaváček Petr , Souček Kamil , Bodnárová Lenka , Foldyna Josef , Zajícová Vendula , Berčáková Andrea , Foldyna Vladimír 
Published: November 2019

Abstract
Concrete structures affected for a long time by flowing liquids are exposed to gradual erosion in surface layers caused by a combination of several degradation processes: abrasion, cavitation and chemical or bacterial impacts. Due to the complex phenomena and difficult-to-define initial and boundary conditions, the whole process cannot be easily simulated using the conventional computing tools. Laboratory experimental research is thus the most appropriate approach for the investigation of a suitable composition of concrete resistant to the flowing liquids. However, the methods used are often very time consuming and last even several years. High-speed water flows can be elegantly used for the acceleration of the mechanical simulation of a real situation. Several experiments on the effects of the high-speed water flows on concrete surfaces have been carried out. Using the X-Ray CT methods, subsurface structures of concretes exposed to the accelerated mechanical simulation of the erosion wear caused by fast flowing liquids were investigated and presented in the article. It has been shown that the simulation does not cause initiation of new fractures or cracks in the original concrete structure. The pure water flow mainly removes the hardened cement paste and reveals the aggregate grains. The water flow with abrasive particles disintegrates in greater depths and washes out entire aggregate grains, eventually amputates them and finally smoothens entire surface.