Hydraulic Shovel Research Articles

Using Telemetry to Assess Operator Effects on Hydraulic Shovel Energy Efficiency. Part I: Algorithms for Extracting Explanatory Variables from Sensor Data

Using Telemetry to Assess Operator Effects on Hydraulic Shovel Energy Efficiency. Part I: Algorithms for Extracting Explanatory Variables from Sensor Data

ТЕХНОЛОГИЯ СЕЛЕКТИВНОЙ ВЫЕМКИ МАЛОМОЩНЫХ УГОЛЬНЫХ ПЛАСТОВ СЛОЖНОГО СТРОЕНИЯ ГИДРАВЛИЧЕСКИМИ ЭКСКАВАТОРАМИ

A method for determining the height of the worked layer by a hydraulic excavator with a reverse shovel when working out low-power coal seams of inclined and steep fall is proposed. Schemes have been developed for mining coal seams of complex structure, which are presented in the form of a synclinal, anticlinal fold, using a hydraulic excavator reverse shovel with separation into layers. The dependence of the height of the worked layer on the angle of incidence and the power of the coal seam is established.

Анализ применения безвзрывных технологий в условиях криолитозоны

Operation of mining equipment has been analyzed at coal, diamond mining and other min-ing enterprises in conditions of cryolithic zones. Hydraulic breakers, dynamic buckets on ex-cavators, rippers on bulldozers, bar cutters, continuous mining machines, and in some cases, rotary mechanical shovel are used in blast-free mining. It is noted that the hydraulic shovels are characterized with high excavation forces, can be used in selective mining, can clean the foot wall without using a bulldozer, and can reduce or sometimes completely eliminate drill-ing and blasting operations. Boundary values of the face slope angle depending on the ambi-ent temperatures were established during the tests of RS-5500 at the Neryungrinsky open pit mine. Its value is equal to 46º in positive temperature; while during the interseasonal pe-riods the value stands at 60º, and in conditions of extremely low temperatures this value reaches 72º. Experience of using the LIEBHERR hydraulic shovels in building stone quarries shows that the uniaxial compressive strength of the rocks developed without blast pre-conditioning can reach 20-150 MPa. The Caterpillar company proposed a technology for ripping and excavating rocks (up to hard rocks) with quickly replaceable attachment tools. Based on analyzing physical and mechanical properties of the overburden rocks and coal at the deposit with account of cutting forces of the working tool, Mining Institute of the North of Siberian Branch of the Russian Academy of Sciences justified the possibility of using and es-tablished estimated performance parameters of the KCM-2000P Continuous Miner for the rocks and coals of the Elga deposit. Taking into account mining and geological conditions and rock properties of the Elga deposit, specialists of Wirtgen International GmbH calculated the technical and economic parameters of coal and overburden excavation using the Wirtgen 4200SM Surface Miners with loading into the 130-ton dump trucks.

Multi-objective optimization of hydraulic shovel using evolutionary algorithm

Hydraulic shovel is widely used in mining industry around the world for materials excavation and loading. The mechanical design of hydraulic shovel remains a challenging optimization problem. To address this issue, we establish the many-objective optimization model of a new type hydraulic shovel named TriRocker. An improved reference points-based many-objective differential evolution algorithm is proposed to solve the optimization problem which outperforms twelve state-of-the-art multi-objective and many-objective evolutionary algorithms in the case study. Then the most satisfactory solution is chosen from the obtained non-dominated solutions by a multicriteria decision-making method. Based on the selected solution, a wonderful design of TriRocker hydraulic shovel is obtained. Furthermore, a marketable prototype of 85-ton TriRocker hydraulic shovel is developed by the proposed optimization method. The result demonstrates the feasibility and effectiveness of the many-objective evolutionary algorithm and multicriteria decision-making method in solving the optimization problem of hydraulic shovel.

Опыт применения гидравлических экскаваторов в сложных горно-геологических и климатических условиях

The article summarizes the experience of using hydraulic excavators in coal, diamondiferous and other mining operations. It is noted that the excavation capacity of modern hydraulic excavators is several times higher than that of the mechanical shovels, and the hydraulic equipment is more suitable for non-explosive excavation in hard grounds, including halfrock formations. It is shown that even in difficult mining, geological and climatic conditions in coal, diamondiferous and other mines, the use of hydraulic excavators in Russian mining companies is justified by high efficiency and high availability ratio equal to the international indicators, which are not lower than those achieved in much more favorable conditions. Research performed in industrial settings made it possible to determine the hydraulic drive's service mode and regulations, as well as rational operating conditions. Operating systems were developed with heated working fluids to compensate for the changing viscosity at low atmospheric temperatures. Based on the tests performed in Russia and abroad, blast-free excavation using hydraulic excavators is done with limited capacity (up to 400 m3/h), and the operating weight of the machines must be not less than 300 tons. The main factors, typical for operation of the open-pit hydraulic excavators include the high annual production time, high forces and dynamics (up to 70 kN per 1 m3 of the bucket capacity) in the digging mode of the unit working at the face, high specific capacity and remoteness from the outside infrastructure used for repairs of the hydraulic components. In the course of testing the hydraulic excavators, the boundary values of the face slope angle depending on the ambient temperature were established. It was experimentally proved that at top to bottom layer-by-layer excavation with the H-285S hydraulic shovel the face height can reach up to 25 m at the rated digging height of 16 m. The average lump size (not more than 300 mm) of the rock mass in a 19 m3 bucket was determined with the permissible oversize in the face up to 2,500 mm. With the normal maintenance quality, the weighted average cost of operation for electromechanical excavators and the corresponding figures for hydraulic excavators are at a comparable level.

Justification of the technological scheme parameters for the development of flooded deposits of construction sand

The article describes the main types of technological schemes for working out the flooded strata of sand deposits using hydraulic shovel excavators. The analysis of scientific and technical literature describing the experience of using hydraulic shovel excavators in the open-pit mining, including pits for the extraction of construction sand, has been carried out. The proposed technological scheme is that the development of reserves of the flooded strata without preliminary water reduction is carried out by a hydraulic shovel excavator from under water by a downward digging with the storage of the extracted rock mass in bulk (for dewatering), placed in such a way that when working out the next mining bench width, it is located within the working area of the excavator for simultaneous processing of the next bench width and loading of dewatered sand from the pile. Calculations of the parameters of the operating platform and the excavator block of the proposed technological scheme for conducting open-pit mining were carried out. The dependence for determining the minimum length of the mining operations front of an excavator for drawing up a technological scheme of operation of a backhoe hydraulic excavator on working out the flooded strata with the pile formation for dewatering sand and its subsequent uploading from the pile by the same excavator is presented.

Heat Transfer and Pressure Drop Performance of a Hydraulic Mining Shovel Radiator by Using Ethylene Glycol/Water-Based Al2O3 Nanofluids

Nanofluids are excellent replacements for vehicle radiator coolants and they have the ability to significantly enrich the performance of vehicle radiators. A numerical study of thermal and hydraulic performance of a hydraulic mining shovel radiator working with nanofluids is carried out. It is observed so far that there are no research works done before analyzing the radiator of this mining equipment. Aluminum oxide in ethylene glycol as nanofluid with volume concentrations of 0.5%, 1.0% and 1.5% were investigated. The results showed that the heat transfer performance of the radiator can be hindered if thermal operating parameters of the equipment are not varied to take advantage of the benefits done by nanofluids. Additionally, it has been found that the pressure drop performance on the radiator operating in laminar and transitional conditions can reduce pressure drop and therefore pumping power. The analysis presented in this paper concluded that the use of nanofluids essentially depends on thermal and flow conditions.

Об определении параметров забойных блоков при ведении горных работ обратными гидравлическими лопатами

The backhoe hydraulic shovels (backhoes) have been widely used in open-pit mining operations in the Kuznetsk coal basin since the early 2000s. Now their number is growing every year, both because new operations begin on new sites, and because of the backhoe advantages. However, up to now parameters of their operation, more particularly the parameters of the face blocks, are often taken according to the actual data, i.e. based on the accumulated experience of the mining companies, and are not calculated using the approved scientifically validated methods. In the given article the authors give some preconditions for creation of a uniform methodology to calculate parameters of the face blocks depending on mining-geological and miningtechnical conditions. It is noted that the manufacturers of excavation equipment quote the data corresponding to the maximum possible parameters of the equipment operation, in particular the height of the excavated layer, as a result of which it is rather difficult to apply this in practice. Preliminary conclusions about the need to take into account the diversity of the above conditions and their interrelation with the parameters of a particular model of the excavation and loading equipment have been made.

Evaluating the impact of excavator bucket capacity on the output of a haul truck in different variants of their positioning

When studying the influence of excavator bucket capacity on haul truck loading time, it is necessary to assess the technical and economic performance of the complex. If the cost of the machine shift of the complex will not cover the increase in productivity, then it is inexpedient to use this complex. This issue requires further, more detailed study and performance of detailed technical and economic analysis. Also, it is necessary to consider classical recommendations about ratio of excavator bucket capacity and haul truck body. It should be noted that at present, there is a significant divergence in the size range of excavators: powerful, with a large capacity bucket, rope shovels are used for mining the coalless zone; small maneuverable hydraulic shovels – for mining the coal-bearing zone. In this paper, we will try to combine the first and the second: consider hydraulic excavators with maximum bucket capacity, which is reasonable to use when mining overburden. In addition, a detailed study of the options of mutual arrangement of excavator and haul truck has not been performed until recently, this work is intended to fill this gap.

Grain-size control in coal and carbonate rock mining

The prime cost of coal and carbonate market products depends on grain size composition and strength characteristics of minerals produced. The grain size composition of mineral products is governed by geological structure of deposits and by mineral mining technology. The volumes of geological blocks and grain size distribution in bedded deposits are conditioned by density of natural joints. Blastless mining technologies applied in coal and carbonate deposits produce block sizes which are much less than natural block sizes in rock mass. It is possible to change the actual/natural block size ratio by selective preparation of different mineral layers to extraction with appropriate choice of mining and handling equipment. The grain-size control and preservation of strength characteristics of rocks is possible using specialpurpose blasting techniques and improved extraction-and-loading technologies. In particular, buried blasts at a powder factor of 0.10–0.15 g/m3 make it possible to split a rock mass layer along a system of natural joints. The buried blasting experience is gained in mining operations in Ekibastuz and Shubarkol coal fields, in Dobryatinsky and Kasimov limestone deposits, and in other mineral extraction projects. In order to simplify extraction of heterogeneous layers, it is suggested to reduce the height of an extraction panel to 1.5–5 m and to employ hydraulic rear shovels with special-design buckets in extraction-and-loading.

Improving the Efficiency of Using Hydraulic Reverse Shovel Excavators on Inclined and Steeply Dipping Fields by Controlling the Overburden Rate

The economic efficiency of open-pit mining is largely determined by the choice of a rational mining regime, which is associated with the problem of averaging the operational overburden rate over periods. At the same time, the authors do not always give recommendations when averaging the operational rates of overburden and the implementation of the selected mode of open-pit mining in practice, most often associated with determining the changing width of the working site throughout its entire existence. The article describes a method for controlling the operational overburden rate when using hydraulic reverse shovel excavators using elements of mathematical modeling of averaging the operational overburden rate, which provides high accuracy of the results and eliminates the influence of the human factor on their calculation.

Modelling for degreasing the mining equipment downtime by optimizing blasting period at Erdenet surface mine

Erdenet copper-molybdenum deposit is the biggest one in the world and has a significant impact on Mongolian society and economy. Today LIEBHERR-994B hydraulic shovels from Germany, electric shovels including EKG-10 and EKG-15 from Russia operate for the mining works, and dump truck BelAZ - 75130 used for transportation. The causes of shovel downtime are classified as technical, technological, and organizational. During the study period, 41% of the total downtime of the excavator’s park was technical, 45% was technological, and 11% was organizational downtime. For shovels, 7% of technological downtime is due to blasting, and for dump trucks 8.7%. In open-pit mining, blasting is performed on a weekly basis, so the duration of this technological downtime can be considered almost constant. If the time between blasts or period of blasting can be arranged optimally, it will be possible to reduce mining equipment’s downtime due to blasting.

Hydraulic excavator versus electric rope shovel performance

Hydraulic excavator versus electric rope shovel performance

EL NIVEL DE SERVICIO DE COMPONENTES CRÍTICOS REPARABLES DE PALAS HIDRÁULICAS

Hydraulic shovels are large-scale equipment that set the pace for the mineral extraction process, so ensuring the service level of your repairable components is considered critical because of its impact on availability.

Optimal Design of Hydraulic Excavator Shovel Attachment Based on Multiobjective Evolutionary Algorithm

The optimal design of TriPower shovel attachment remains a challenging task although TriPower face shovel excavators work well in mines all over the world. To address this issue, we establish the multiobjective optimization model of TriPower shovel attachment, which sets three kinematic indicators and two mechanical indicators as the objective functions. An improved multiobjective evolutionary algorithm (MOEA) based on decomposition is proposed to solve the multiobjective optimization problem, which outperforms several representative MOEAs in the case study, and a lot of nondominated solutions are obtained. Then, the most satisfactory solution is selected based on the technique for order of preference by similarity to ideal solution method. Based on this solution, an excellent design of TriPower face shovel excavator is obtained, which can fully realize the three features of TriPower shovel attachment. These results demonstrate the feasibility and effectiveness of the MOEA and multicriteria decision-making method in the optimal design of hydraulic excavator working attachment.

Features of the Excavation and Loading Equipment of Various Types in the Development of Inclined and Steep Beds

Open pit coal mining enterprises are constantly faced with the task of increasing the economic efficiency of mining, reducing coal losses and increasing profitability. One of the ways to increase the efficiency of open-pit mining is the improvement of the technology for developing coal-bearing zones of quarry fields in sloped and steeply complex (hard-structured) deposits. Currently, projects for promising deposits have been completed, and a number of existing sections are developing coal-bearing zones across their entire width in horizontal layers. Extraction and loading equipment for stripping and winning operations in this area is characterized by a wide variety: rope shovels (also called power or stripping shovels), backhoes and hydraulic shovels or their joint work. When using only rope shovels or only backhoes, they produce an excavation of both interbeds and coal seams. When they work together in the coal-bearing zone, the rope shovel makes a stripping of the interbeds, and the backhoe – an extraction of the coal seams. However, such technical solutions are not sufficiently substantiated. The fact is that rope shovels and backhoe shovels have their advantages and disadvantages in operation.

The Analysis of Conditions of Hydraulic Backhoes Use in the Coal-Bearing Zones at Kuzbass Open Pits

The period of open pit mining development in Kuzbass (Western Siberia, Russia) until the mid-1990s was characterized by the application of rope and hydraulic shovels in coal-bearing zones, the work of which is not effective enough due to a decrease in productivity in mining operations, high losses and dilution of coal. The supply of this type of excavators was fully provided by Russian excavators' manufacturers. With the transition to market relations since the early 90's, in the coal industry of the Kuzbass two interrelated phenomena have occurred. First, the restructuring of coal industry and the massive privatization of licensed development of explored deposits forced a sharp increase in the open pit construction (from 24 in the early 1990's to 62 now). Secondly, the bankruptcy of excavators' manufacturers led to a reduction in the volume of production of domestic rope shovels. So the problem of defining the conditions of hydraulic backhoes use in the coal-bearing zones became very important.

Coal-Bearing Zone Transformation into a Coalless One at the Open Pit

Currently, two types of handling machines are mainly used on coal open pit mines in Kuzbass, characterized by complex structural deposits: mechanical (rope) and hydraulic (backhoe) shovels. Moreover, both types of equipment are supplied to the quarries: mechanical shovels are purchased, as a rule, powerful with a bucket capacity up to 56 m3, backhoes – small and medium-size models with a bucket capacity of 2.8-14 m3. On the other hand, it is common to divide the areas of equipment use in the open pit on complex-structured deposits into a coalless (outside the strata of coalbeds) and coal-bearing (actually a series of beds, including coal strata and rock interbeds). The use of these equipment types in both design and industrial practice is observed in both zones. At the same time, it is known that each of these zones has different conditions for the efficient operation of excavation machines. The seams, therefore, do not complicate the coalless zone when working in it, favorable conditions are provided for the excavator: the constant height of the bench, which is necessary for the full filling of the bucket for one scoop, the constant width of the panel and the length of the front of the work. In these conditions, the maximum productivity of the excavator is ensured.

Driven System and Characteristics Research of Large Hydraulic Shovel Swing Motion

Driven System and Characteristics Research of Large Hydraulic Shovel Swing Motion

Energy Management for an 8000 hp Hybrid Hydraulic Mining Shovel

There has been an increasing interest in concept of hybrid architecture which is penetrating the heavy industry machines, in recent years, including for hydraulic mining shovels (HMSs). Achieving increased machine efficiency, productivity, and performance, reduced emissions, and prolonged lifetime are the main goals in developing hybrid shovel structures. This paper presents the energy management concept for an electric HMS, which uses high power density energy storage systems to supplement the diesel-powered generators. A 2.25-MW ultracapacitor system is applied to improve the sluggish dynamic response of the diesel engines during sudden load changes and to reduce the engine power requirements by maintaining an optimal engine speed. In addition to the engine dynamic improvement, the ultracapacitor system supports the engine during peak power demand allowing for a smaller engine size, which results in higher fuel savings and less exhaust emissions. Detailed control schemes for the converters and system are described. Results of simulations, off-board testing, and on-board testing for an implemented 8000 hp mining shovel are provided and discussed. The machine operates smoothly at varying load conditions. The initial assessments indicate a 30% increase in machine productivity and 26% increase in fuel efficiency compared with a 120-ton conventional hydraulic machine.