Calculation of Free Interior Dimensions in Geokhod Transmission With Hydraulic Cylinders

Analytical expressions to specify overall dimensions of free interior in the geokhod, as well as its relation to design factors of a transmission and geokhod geometry are considered in the paper

Physicochemical Processes of Metal Lixiviation in the Disintegrator

The results of lixiviation-based recycling of ore mill tailings in the high-speed disintegrator are presented. The regularities of the change in properties are defined, as well as control directions over them via alteration of variable processing factors are defined. The model to determine the economic effect of the use of solidifying mixes based on mill tailings is proposed. The model of perfectly mixing reactor cascade in continuous operating conditions is developed to describe activation on minerals in the disintegrator

Control of Rock Mechanics in Underground Ore Mining

Performance indicators in underground mining of thick iron fields can be insufficient since geo-mechanic specifics of ore-hosting fields might be considered inadequately, as a consequence, critical deformations and even earth's surface destruction are possible, lowering the indicators of full subsurface use, this way. The reason for it is the available approach to estimating the performance of mining according to ore excavation costs, without assessing losses of valuable components and damage to the environment. The experimental approach to the problem is based on a combination of methods to justify technical capability and performance of mining technology improvement with regard to geomechanical factors. The main idea of decisions to be taken is turning geo-materials into the condition of triaxial compression via developing the support constructions of blocked up structural rock block. The study was carried out according to an integrated approach based on the analysis of concepts, field observations, and simulation with the photo-elastic materials in conditions of North Caucasus deposits. A database containing information on the deposit can be developed with the help of industrial experiments and performance indicators of the field can be also improved using the ability of ore-hosting fields to develop support constructions, keeping the geo-mechanical stability of the system at lower cost, avoiding ore contamination at the processing stage. The proposed model is a specific one because an adjustment coefficient of natural and anthropogenic stresses is used and can be adopted for local conditions. The relation of natural to anthropogenic factors can make more precise the standards of developed, prepared and ready to excavation ore reserves relying on computational methods. It is possible to minimize critical stresses and corresponding deformations due to dividing the ore field into sectors safe from the standpoint of geo-mechanics, and using less cost-demanding ways of keeping rock massif stable

Combined Delivery of Consolidating Pulps to the Remote Sites of Deposits

The problems of modern mining production include limitation of the scope of application of environmental and resource-saving technologies with application of consolidating pulps when developing the sites of the ore field remote from the stowing complexes which leads to the significant reduction of the performance indicators of underground mining of metallic ores. Experimental approach to the problem solution is characterized by the proof of technological capability and efficiency of the combined vibration-pneumatic-gravity-flowing method of pulps delivery at the distance exceeding the capacity of current delivery methods as it studies the vibration phenomenon in industrial special structure pipeline. The results of the full-scale experiment confirm the theoretical calculations of the capability of consolidating stowing delivery of common composition at the distance exceeding the capacity of usual pneumatic-gravity-flowing delivery method due to reduction of the friction-induced resistance of the consolidating stowing to the movement along the pipeline. The parameters of the interaction of the consolidating stowing components improve in the process of its delivery via the pipeline resulting in the stowing strength increase, completeness of subsurface use improves, the land is saved for agricultural application and the environmental stress is relieved

From Mining to Post-Mining: The Sustainable Development Strategy of the German Hard Coal Mining Industry

By the end of the 1950s, the German coal mining industry produced 150 million tons of hard coal per year in 170 collieries with 600,000 employees. At that time, 70% of the primary energy demand of the Federal Republic of Germany was covered by domestic coal. Since the advance of oil, later of natural gas, in the world energy market and with the growth of world coal trade, domestic coal stood under a long-term restructuring pressure. This decision required a new strategy for the coal mining industry. Now German coal mining will be strictly finalized and will be prepared for the post-mining era. Within a sustainability strategy the long-term impacts of mining activities before and after the mine closures concerning the environmental, economic and social dimensions will be analyzed systematically and forward-looking

Determination of Radius of Curvature for Teeth With Cycloid Profile

In the article the geometric determination of curvature radius is considered for teeth with cycloid profile. The equations are obtained for the determination of a radius of curvature with point coordinates of a cycloid profile. The conditions of convexo-concavity of a teeth profile are defined for transmission with intermediate rollers

Power Parameters Automated Calculation for Transmission with Intermediate Rolling Bodies and Free Cage

In the article, techniques complex of the transmission with IRBFC power parameters determination are considered. Moreover, software of automated calculation of the power parameters is created based on the techniques. The software consists of two parts: program of the mechanical transmission creating as a computer object; program of the graphical user interface creating. In general, the software makes it possible to determine the distribution of forces and contact stresses in engagement along the cycloidal profile of gear, to determine the maximum force and contact stress in engagement and to generate a file in excel format with all calculated data

Coal Mining Machinery Development As An Ecological Factor Of Progressive Technologies Implementation

At present, a significant amount of energy spent for the work of mining machines and coal mining equipment on coal mines and open pits goes to the coal grinding in the process of its extraction in mining faces. Meanwhile, the increase of small fractions in mined coal does not only reduce the profitability of its production, but also causes a further negative impact on the environment and degrades labor conditions for miners. The countermeasure to the specified processes is possible with the help of coal mining equipment development. However, against the background of the technological decrease of coal mine equipment applied in Russia the negative impact on the environment is getting reinforced

Rational Use of Land Resource During the Implementation of Transportless System of Coal Strata Surface Mining

Surface mining and open pits engineering affect the environment in a very negative way. Among other pollutions that open pits make during mineral deposits exploiting, particular problem is the landscape changing. Along with converting the land into pits, surface mining is connected with pilling dumps that occupy large ground. The article describes an analysis of transportless methods of several coal seams strata surface mining, applied for open pits of South Kuzbass coal enterprises (Western Siberia, Russia). To improve land-use management of open pit mining enterprises, the characteristics of transportless technological schemes for several coal seams strata surface mining are highlighted and observed. These characteristics help to systematize transportless open mining technologies using common criteria that characterize structure of the bottom part of a strata and internal dumping schemes. The schemes of transportless systems of coal strata surface mining implemented in South Kuzbass are given

Development of an Algorithm for Computing the Force and Stress Parameters of a Cycloid Reducer

The paper is devoted to the development of an algorithm for the automated calculation of force characteristics of cycloid toothing when the initial parameters vary widely. The algorithm forms a structured data array that accelerates finding and outputting the necessary parameters and reduces the probability of error in determining these parameters. The algorithm serves the basis for a program that allows for the examination of the change in force and geometrical parameters in various combinations. The study includes the analysis of the dependence of forces and contact stresses in transmission toothing with intermediate rolling elements and a free cage on the initial parameters of this transmission. The obtained results will make it possible to select optimal combinations of initial parameters in order to minimize the force impact on the mechanism parts when designing modern compact mechanisms based on the cycloid with intermediate rolling elements and a free cage