Time filter

Source Type

Saint Petersburg, Russia

Madissoo M.,Estonian University of Life Sciences | Rossner A.,Estonian University of Life Sciences | Olt J.,Estonian University of Life Sciences | Maksarov V.,National Mineral Resource University
Medziagotyra | Year: 2015

The paper focuses on testing the utility effect of a cutting tool holder with inserted alternate bars of different material structure in its construction. The different bars are made from rolled steel and have an anisotropic structure which also has different mechanical properties. This construction is considered as a method to improve the cutting stability of the cutting tool and helps to reduce the oscillations in the finishing turning. A method for the construction of the damped instrument holder is proposed. A series of comparative experiments was carried out with both the standard and the modified tool holder. In the cutting tests only the feed rate was changed, cutting speed and the depth of cud remained always the same. All tests were repeated three times. After each cutting the surface roughness of all the treated surfaces were measured and compared. Surface roughness measurements revealed that the average surface roughness improved 9 % with the use of the modified tool holder. Only in one case, at the feed rate of 0.1 mm r-1 a poorer surface roughness with the modified holder was achieved. © 2015, Kauno Technologijos Universitetas. All rights reserved. Source

Maksarov V.,National Mineral Resource University
Agronomy Research | Year: 2015

The article introduces new results on designing multilayer cutting tool holder. Experimental study of metal turning process workpieces shows efficient dynamic damping of oscillations. The coefficient of oscillations absorption and damping is increased due to large dissipative force of the material holder oriented in different deformation directions of holder material. © 2015 Eesti Pollumajandusulikool. All rights reserved. Source

Argimbaev K.R.,National Mineral Resource University | Kholodjakov H.A.,National Mineral Resource University
Research Journal of Applied Sciences | Year: 2016

Results of numerical models for rock mass stress-strain behavior presented in the paper allow to reduce the risk of technogenic accidents during mineral deposits open-pit mining with taking into account the construction sequence, the pit depth and the degree of water cut. The methods in which the continuous medium is approximated by a discrete model at the stage of the numerical model development are referred to the computational methods of rock mass stress-strain behavior forecasting. In this case where further idealization when formulating and solving equations is not applied, integration is replaced by finite summation and partial differential equations are replaced by systems of linear algebraic or ordinary differential equations. In addition, the continuous medium is replaced by a discrete model having a finite number of degrees of freedom. © Medwell Journals, 2016. Source

Sizyakov V.M.,National Mineral Resource University | Tikhonova E.V.,National Mineral Resource University | Cherkasova M.V.,National Mineral Resource University
Non-ferrous Metals | Year: 2013

The Bayer process aluminate solutions are characterized by accumulation of organic compounds, which worsen the manufacturing parameters and quality of produced alumina. Sorption methods of purification are the easiest and the most efficient. Sorption characteristics of activated carbon, magnesium oxide, hydrated carboaluminates and sulfoaluminates of magnesium are considered, concerning organic chemistry of aluminate solutions. Extra-sorbtion mechanism was defined during the processing of aluminate solutions by activated magnesia. There was also defined the high sorption potential of magnesium hydro aluminate phases. Advantages of such compounds consist in the following factors: - likeness of sorbent composition to the system; - absence of influence on solution's technological structure; - low power expenses for reagent regeneration (at the temperatures of 250-400 °C). The foregoing characteristics of synthesized sorbents can be the basis for development of technology of aluminate solutions purification from organic compounds by active sorbents (hydrated carboaluminates and sulfoaluminates of magnesium). Source

Maksarov V.,National Mineral Resource University | Khalimonenko A.,National Mineral Resource University | Timofeev D.,National Mineral Resource University
Agronomy Research | Year: 2014

The article deals with the problems of improving quality of parts machined on lathe type machine tools. Improvements are suggested by predicting the operability (tool life parameter) of cutting tools equipped with replaceable ceramic inserts. It is proposed to forecast the operability of ceramic tools on the ground of relation between operational characteristics of the ceramic and microstructural parameters of the ceramic material. Microstructural parameters of ceramic inserts are determined by non-destructive testing method, evaluating them by estimating the specific electric resistance of the material. As a result of research, a relation has been detected between operability of the inserts and the specific electric resistance of the insert material. Obtained results permit one to determine the stability range borders for lathing blanks with tools equipped by ceramic cutting inserts and to predict flawless work. Source

Discover hidden collaborations