31 research outputs found
Controlled cascading waterfall technology of crushing raw materials on the value of its current strongholds
The results of laboratory studies of innovative technology for grinding raw materials are presented. Grinding technology is one of the most energy-intensive industries in the industry. The obtained data confirm the possibility of obtaining breakthrough technical and economic indicators in the implementation of the proposed innovative technology of grinding raw materials in ball mills. The latter is achieved by maintaining in them the optimal trajectories of intra mill loading on the basis of the use of a controlled cascade-waterfall grinding mode, depending on the constantly changing physical and mechanical properties (grind ability, strength) of the ground product. At the same time, the mill effectively implements the most efficient grinding regimes (blow, abrasion, crushing), depending on the current strength of the crushed raw materials. Tests have shown the possibility of reducing the specific energy consumption depending on the strength of the crushed material by 31-44 % with a simultaneous increase in the performance of the mill for raw materials of various strength classes by 22-57 %. For the industrial tests of the proposed technology, two systems of automatic control of the strength of the comminuted material in the mill have been developed
Numerical check of a 2DOF transmission for wind turbines
The aim of the paper is to present a planetary gearbox for wind turbine. At constant wind power input the planetary gearbox is able to provide variable speed of the output shaft. The main purpose of the differential transmission is on the capability to adapt the operation to variable loading of wind. A CAD model has been proposed in order to investigate the operation feasibility of the proposed design solution. A proper dynamic model has been developed in ADAMS software. Simulation tests have been carried out and results are discussed to validate the proposed design solution
The interaction of the freight car and way taking into account deformation of assembled rails and sleepers
The settlement scheme is made and analytical researches of fluctuations of crew under the influence unevenness of the way in the horizontal and vertical planes taking into account impact of the railroad car on the way are executed
Characterization of tribological behavior of high performance rail steel
The tribological characterisation of rail steels has been carried out using rolling-sliding testing device with cylindrical samples with functional geometries. The test can be considered in accordance with the similar one prescribed by the GOST normative. Two steel grade, R260 and K76 Φ have been used for the laboratory characterisation. Wear curves have been carried out and elaborated depending on the in service conditions and wear amounts of the rail. The test is suitable for the comparative wear analysis of rail steels. The experimental results were compared with the curves from scientific and technological literature and with values measured from in service rails to be validated
Study of thermal stonecutting tools
The paper discusses the issues related to facing stone production of hard-rock granite rocks. It describes the rational methods for producing dimension stones and designs of thermal tools to destruct rocks in processing and production of dimension stones. The designs of thermal tools characterized by increased output performance has been developed as a work tool for power-operated unit of stone-cutting machines
The kinematic analysis of flat lever mechanisms with application of vector calculation
Linkwork, in its early applications, consisted mainly of revolute-connected members and was widely used for converting the continuous rotation of a water wheel into a reciprocating motion suited to piston pumps. The piston-cylinder combination at the end of the line represents a prismatic pair, of course, but ahead of this there are only the revolute connections generally associated with linkwork. Agricola’s arrangements show wheel and pump-power source and point of work-fairly close together. Such compactness did not always prevail; link-works of magnificent proportions were also part of the past. A linkwork is a means of power transmission as well as being a motion transformer. Before the introduction of rope transmissions and the now universal electric wire, linkwork was employed for long-distance transmission of power. Gigantic linkages, principally for mine pumping operations, connected water wheels at the riverbank to pumps high up on the hillside
Seismic resistance of horizontal underground openings in anisotropic rocks
Fine-layered mountain mass with plane-parallel inclined layers is presented by anisotropic (transtropic) body with inclined plane of isotropy. A long horizontal cavity of arbitrary orientation and section shape is that medium; it is strengthened by an elastic anisotropic finishing. The interaction between the finishing and viscos-elastic rock medium is studied. The seismic-stress state of the “inishing-rock” system under aggregate action of long tension-compression and shear waves in conditions of generalized plane strains is investigated by using the quasistatic approach and complex potentials method. The procedure of research of seismic oscillations of a complex structure rock with multipurpose underground cavity using finite elements method and strong earthquake oscillograms is presented here
The kinematic analysis of the third class mechanism
It is necessary to make link mechanisms calculation to the strength at designing of flat link mechanisms of high class after definition of block diagrams and link linear sizes i.e. it is rationally to choose their forms and to determine the section sizes. The algorithm of the definition of dimension of link mechanism lengths of high classes (MHC) and their metric parameters at successive approach is offered in this work
Optimal Design of Leading Kinematical Chain of Eight Linked Planar Load Lifting Linkage
The problem of optimization of force transmission in planar linkage is concerned. New kinematical design of hoisting device with straight-line and translational motion of a platform is proposed. The method of optimal synthesis of leading kinematical chain of hydrocylinder is explored and multiobjective design is carried out based on Sobol-Statnikov’s technique. Since the general solution of the modern theory problem of dynamics and strength of machines is absent, then it is an actual problem.
DOI: 10.5901/mjss.2014.v5n23p265
The experimental determination of the stress calculation and relative strains in the span elements of railway bridges under the influence of the rolling equipment
Some results of measurements of bending deformation concrete span bridge are given. It is shown that for a more detailed estimation of the dynamic answer of the structure and the establishment of the correspondence between the analytical model and behavior of structure, it is necessary to carry out periodic monitoring of tense-strained state of the structure under operating load