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The purpose of the study is to evaluate the energy parameters of tower cranes when using a frequency-controlled drive mechanism. The relevance of the study lies in the fact that existing tower cranes quickly become obsolete. However, there is an alternative to buying new cranes – the modernization of existing ones with the improvement of their parameters and the scientific justification for increasing the efficiency of work. The following methods are used for research: method of equivalent power and the methods of metal fatigue theory. The main scientific novelty is the approach to assessing the possible increase in the service life of crane elements when using a frequency drive based on the theory of fatigue. Also presented are examples of equivalent power calculations for the working cycles of the turning mechanism with various forms of speed change in acceleration and deceleration modes. Numerical estimates are given for increasing the service life of the main types of welded joints with different values of stress concentration factors. Showing ways to further improve the efficiency of tower cranes and their mechanisms due to more optimal transients. The proposed approaches can be used when choosing the type of drive for the designed crane or to evaluate the economic efficiency of replacing the drive.

The concept of rhinogenic headaches remains a subject of much debate. While many authors have reported good results in treating these headaches with endoscopie sinus surgery, few have attempted to establish objective criteria for identifying the best surgical candidates. We conducted a study of 33 adults with rhinogenic headaches to determine if three elements of the history and/or five aspects of computed tomography (CT) would predict which patients might benefit from the minimally invasive sinus technique (MIST) as the primary treatment modality for their headaches. Postoperative follow-up interviews revealed that endoscopie surgery was widely successful, as 28 patients (84.8%) reported improvement. However, we were unable to find any statistically significant history or CT parameters that predicted surgical outcomes. [ABSTRACT FROM AUTHOR]

Main part of crane systems in general and hoisting systems especially are rope-reeving systems. They are used to reduce the loading on the rope itself and on the following parts in the hoist drive. In order to transfer the performance required the reduced loading has to be compensated by higher speeds. General standard are reeving systems with just vertical rope orientation. They have advantages, as they are not difficult to plan, to build and to operate. On the other hand, they comprise disadvantages as well. One main disadvantage of vertical rope orientation is the tendency to load sway.

Dewatering of water-coal slurry or thickened product under conditions of operating SUEK-Kuzbass JSC enrichment plants is a promising direction of obtaining technogenic mineral resources. It should also be noted that the quality of the obtained product will be directly influenced by the quality of the initial raw materials. If the content of carbon particles is high and the average ash content of the solid phase is low, such a slurry will be of interest in terms of obtaining additional volumes of coal after dewatering. The object of this study is water-coal slurry obtained at the outlet of the radial thickener (thickened product). The subject of the research is technology of thickened product dewatering with the use of shell filter constructions. The aim of the work is to develop and substantiate parameters of low-cost technology of thickened product dewatering to ensure an increase in economic and environmental efficiency of mining operations. The idea of the work is to use the laws of mass transfer of suspended particles of water-coal slurry by filtering through specially made shell filter constructions (SFC).

The paper describes a method for determining the density and specific surface of the package of rock particles represented by discs with the size corresponding to the size of the rock fragments of real dump massifs (2D case). The packing method of the particles corresponds to the schemes of dumping used in open-pit mining - areal and peripheral ones. The influence of boundaries, in which the dump is located, on the physical characteristics of this massif - density and porosity - is revealed. It was revealed that the way of formation of the bulk of particles affects its density, especially at the boundaries of the massif. The massif of particles formed in accordance with the area technology of dumping has a denser composition and is less affected by the effect of its boundaries than the massif formed in accordance with the peripheral technology of dumping. The applied method of determining the physical characteristics of the bulk medium differs from the statistical methods (e.g., Monte Carlo) and is well-proven for static media, such as dumps and filtering massifs in open-pit mining.

Sustainable development today covers not only certain aspects of the environmental and economic aspects of society. The very structure of the economy, in particular the production sphere, as well as the whole society, is changing radically. Moreover, the structure is not only a systemological, but also the category of sustainable development. It acts as the basis of any material phenomenon or process, that is, it serves as a relatively stable basis on which more mobile elements function. Therefore, the closest concept that allows revealing the essence of sustainable development, the problem of cognition of environmental and economic transformations, transformations and their regulation, is the structure. It is by using the disclosure of the structure as a fundamental element of the system of sustainable development that can reveal the factors of deep changes in the economy, under the influence of which the transformation of industry towards modern environmental guidelines, and with it employment, investment, innovation, systems of their state regulation.

With EN 13001-1 ff. a harmonized set of standards for safety of cranes was and is established. Due to harmonization the use of the standards leads to the assumption of conformity with the safety requirements of the machinery directive. A major argument for the application of the standards. The standards comprise new concepts of proof of competence in comparison to previous standards. Keywords of these new concepts are “Classification”, “Limit state method”, “Mass Distribution Class” and “Partial safety factors”. The article gives an overview to EN 13001-1, EN 13001-2 and EN 13001-3-1. This is the set of standards for proof of the structural parts of a crane. The main aspects of the standards are shown and discussed with regard to their impact on calculation.

At the Centre of Drive and Lifting Technology ZAFT of Technische Hochschule Georg Agricola a new testing device will be available. The device is suitable for testing drivetrain components like safety clutches and hoist safety components like snag protection devices. In focus are continuous tests with regard to fatigue as well as transient tests with regard to switching characteristics. The article gives information on requirements on the testing rig out of the main purpose and out of the given environment. Furthermore concept, main data and engineering design of this equipment are demonstrated. Aspects and first results of the mechanical assembly are shown.

24-26 April, 2017 the Scientific Practical Conference “International Innovative Mining Symposium (in memory of Prof. Vladimir Pronoza)” was successfully organized at T.F. Gorbachev Kuzbass State Technical University - KuzSTU (Kemerovo Russia). More than 20 participants submitted their papers in presence, and more than 40 authors sent their papers for virtual participation. The main participants of the conference - Keynote Speakers - paid special attention to the development of international cooperation of technical universities as a form of accelerating the transfer of innovations in mineral resources mining and processing.

Dynamically operated hoist systems are exposed to different load cases, which may induce high loads to the drivetrain. The paper shows the load cases and additional equipment, to restrict the loads out of these load cases to the hoist. Especially in focus are optional measures for the exceptional load cases emergency stop snag load. The load cases are listed including affiliated equipment and aspects to be considered during design phase.