A. I. Kanareykin (Russian State University for Geological Prospecting (MGRI), Moscow)

Statistical calculation of strength under complex stress conditions

The article is devoted to the issues of strength of brittle materials under various patterns of sample loading. A statistical criterion for the equivalence of inhomogeneous stress states is obtained. The differences in the results of strength calculations obtained by classical statistical methods are also presented.
Keywords: strength; tension; statistical theory of strength; integral probability distribution law.

A. I. Kanareykin (Russian State University for Geological Prospecting (MGRI), Moscow)

Determination of quasi-stationary temperature stresses of a plate with an asymmetric hole

The work is devoted to the issues of thermal stress. It considers the problem of determining the temperature stresses of a plate with an asymmetric hole. It is assumed that the function of the unsteady field is known. The solution was obtained using differentiation and integration methods. The result obtained can be useful for determining the thermally stressed state of products. This opens up the possibility of controlling its stress-strain state in order to avoid disruption of the continuity of the material, leading to a defect in the casting.
Keywords: plate; hole; instability; temperature stresses; deformation.

A. V. Yaroslavtsev (Nosov Magnitogorsk State Technical University, Magnitogorsk); E. V. Lagovskaya, V. V. Pedanova, M. R. Bayguzin, I. A. Evdokimov (Fedorovsky Polar State University, Norilsk)

Structural elements of a simple pump drive of metallurgical machines

A method for leveling the shortcomings of a simple pump drive by introducing hydraulic reducers and multipliers is proposed. A more uniform pump loading is achieved and thereby the quality indicators of a simple pump drive are improved.
Keywords: drive; reducer; multiplier; dispenser; metallurgical machines.

O. V. Burlachenko, A. R. Risunov, A. D. Konovalov (Volgograd State Technical University, Volgograd)

Dependence of wear resistance on the geometric characteristics of excavator working bodies and a combination of technological and design solutions

The article presents a model that establishes the dependence of excavator bucket tooth wear on the geometric parameters of the working body, including the number and pitch of teeth, as well as the properties of the material and processing technology. The results of the study show that the proposed approaches can reduce tooth wear by 40–50 %, which ensures an increase in soil cutting productivity and a reduction in the cost of restoration and repair of equipment during work.
Keywords: durability; wear; forging; surfacing; excavator working bodies; bucket tooth; carbide materials; operational efficiency; wear resistance; wear.

A. V. Petrov (MSUT «STANKIN», Moscow)

Investigation of the effect of processing parameters on the stress-strain state of cutting plates when processing multi-stage holes with a prefabricated step drill with a NSR

This article discusses the stress-strain state of the cutting plates of prefabricated step drills with NSR, resulting from the action of cutting forces during the machining of materials. The study examines the influence of the parameters of the cutting process, namely, cutting speed, feed and cutting depth on the stresses in the cutting elements of the tool. To conduct the research, the method of computer modeling in the SolidWorks Simulation software package was used. The purpose of this study is to identify which processing parameters will have the greatest impact on the stresses that arise. The simulation results made it possible to identify the dependence of changes in the stresses in the tool on various processing parameters. Based on the data obtained, regression equations were constructed that can be used to predict the level of stresses that occur when processing parameters change, and graphs of stress dependence on various processing parameters were constructed. All the results obtained make it possible to optimize the tool design process, and can also be used in developing recommendations for choosing cutting modes.
Keywords: cutting plates; cutting forces; cutting modes; combined tool with NSR; computer modeling.

A. V. Yaroslavtsev (Nosov Magnitogorsk State Technical University, Magnitogorsk); E. V. Lagovskaya, V. V. Pedanova, M. R. Bayguzin, I. A. Evdokimov (Fedorovsky Polar State University, Norilsk)

Statistical assessment of the influence of lubricant on the change in the linear dimensions of work rolls

This article presents a statistical assessment of the change in wear of work rolls with or without the use of lubricant, which will allow predicting the value of the change in the roll profile coefficient and adjusting the volumetric flow parameters of the lubricant supplied to the support rolls.
Keywords: hot rolling; lubricant; metered lubricant supply system.

A. N. Abramov, D. G. Tyulenev, T. I. Gilmanov (Self-supporting Creative Center of Ufa Aviation Institute, Ufa); V. V. Maistrenko (Tries LLC, Moscow)

The result of laboratory and industrial tests of a new domestic quenching oil for heat treatment of elastic terminals of rail fasteners made of 38Si7 steel

The results of laboratory studies and the introduction of domestic hardening oil Rosoil-277 are presented. The effect of the cooling properties and temperature of quenching oils and heat treatment modes on hardness was carried out during heat treatment of 38Si7 steel used for the manufacture of rail terminals. The cooling properties of quenching oils are evaluated using an installation for determining the cooling characteristics of technological and quenching media UZS-2 manufactured by LLC Self-supporting Creative Center of the Ufa Aviation Institute. Pilot industrial tests are carried out in the conditions of LLC Tries using AICHELIN 5/2-90/85/150 equipment for quenching rail terminals made of 38SI7 steel.
Keywords: quenching; quenching oil; heat treatment; cooling characteristics; hardness; microstructure.

T. Yu. Stoyanov, A. K. Efremov (Saint-Petersburg State Marine Technical University, Saint-Petersburg)

Experimental verification of the possibility of using single-pipe samples to assess the tightness of rolled joints of pipes with tube sheets in heat exchangers

During designing heat exchangers, various technical solutions are used to increase the reliability of the connection of pipes with tube sheets, for example, annular sealing grooves or rolled sealing relief. To study the influence of various design factors on the reliability of such connections, samples of future pipe connections with tube sheets are made and subjected to tightness and strength tests. In this paper, an experimental study was conducted on the efficiency of using single-pipe samples as models of pipe connections with tube sheets of a heat exchanger.
Keywords: rolled joint; tightness; annular sealing relief; rolling tool; groover; single-pipe sample; equivalent bushing.

M. I. Panin, A. R. Gareev, N. A. Korchinsky, A. S. Andreev (JSC «NIIgrafit», Moscow); A. I. Goliney (Rosatom Science JSC, Moscow)

Investigation of elastic refueling system of rod production line for forming carbon-carbon composite materials

The paper presents the main provisions for the research of the carbon rods manufacturing process, providing the creation of volumetric reinforcing frameworks for carbon-carbon composite materials (СCCM) and products for the aerospace industry. The analysis of the structural and filling line of threading and its deformation in the working bodies of the rod production line has been carried out, the results of the research of the influence of various factors on the stiffness coefficient of the elastic system of carbon threading and its deformation in each zone of filling, for all technological transitions have been shown. The influence of longitudinal deformation of filament tension and transverse compression deformation in the dies on the structure of filament arrangement in it and, consequently, on the quality of the product (ellipticity and stability) of the formed rods has been studied. Measures for selection of speed modes and optimisation of the line operation are proposed, allowing to increase the quality indicators of carbon rods manufacturing, on the basis of which the final product in the form of structural СCCM is produced.
Keywords: rod; thread; tension; filament; stiffness coefficient; deformation; pliability; die; squeeze.