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In process of shaped profiles experimental rolling, it is often necessary to make adjustments to new roll pass design to ensure their physical filling, control between gaps in the values of real broadenings and reductions. In order to reduce number of possible adjustments in roll pass design process and mastering new profiles, the task of developing a model for calculating roll passes becomes actual. A model for calculating roll pass design for rolling railway rails presented. This model based on roll pass design for rolling R65 rails. The regression equations of deformation logarithmic degree were derived using example of two pre-finishing and finishing roll passes, which were used to calculate UIC60E1 rail roll pass design. A high degree of convergence of the geometry of the calculated and operating roll pass has been established. The maximum deviations from geometry of existing roll pass and calculated ones according to proposed method did not exceed 1-2 mm on each of them. It was shown that the developed model calculates exact roll pass geometry, which can be loaded into the program of a processing machine. The proposed calculation methodology can be used at roll pass design of shaped profiles of the same type of different profile sizes of the same mill, resulting in significant reduction of roll pass designed development time and number of adjustments.

The paper describes the main stages of the development of sectional and shaped profiles by the JSC “EVRAZ NTMK” over the past years. The plant operates three longitudinal rolling mills, each of which has been producing both construction metal structures and transport products for many decades. Every year, market competition causes increased consumer requirements toward product quality and requires expansion of the product assortment. Therefore, developing new profiles is an ongoing process at the JSC “EVRAZ NTMK.” The following transport profiles have been developed: stirrup stop bar, rail pad bar R-65, insulated joint core bar ApATeK R-65 MK-BO, guard-rail angle SP850, subway conductor rail, I-beam No. 19 used in the construction of a center girder of the pivoted unit of the rail cars, and a non-standard I-beam 13C1 manufactured according to the technical agreement with the Research and Production Enterprise (RPE) “Uralvagonzavod.” Due to consumer requests, the heavy-section and rail-and-beam shops of the JSC “EVRAZ NTMK” started production of the U-channel line, since such series is more preferable when manufacturing metal constructions compared to V-channel sloping along the inner side of the flange, previously produced at the JSC “EVRAZ NTMK.” In recent years, the railand-beam shop started production of the entire line of crane rails. In just the past 5 years, over 60 standard I-beam sizes have been implemented under the wide-flange beam rolling shop conditions according to various standards, including a foreign ASTM A6/A6M-2017a standard and BS EN 10365–2017 standard, as well as GOST R 57837–2017 developed by EVRAZ together with the Central Research Institute of Building Structures (TsNIISK) named after V. A. Kucherenko. The process of developing new profiles at the JSC “EVRAZ NTMK” continues. In 2020 alone, it is planned to start production of more than 20 new types and nominal sizes of the hot-rolled sectional and shaped profiles.

In view of increase of ferrous and nonferrous ores mining, the need for grinding balls, used for the ores grinding in the process of concentration, is also increasing. Description of technical solutions, realized at accomplishment of an investment project at JSC EVRAZ NTMK, presented. The investment project on the technical modification of the rail and beam shop included construction of the new ball-rolling mil further to production of steel grinding balls. The new ball-rolling mill, which was put into operation in 2018, has a possibility to produce ball of diameter from 60 up to 120 mm with hardness up to 5th group. The mill is equipped by an automation system of the process and balls stocking control. The ball production section comprises a walking beams heating furnace with automated heating modes to ensure energy-efficient operation; automated hot rolling mill for production grinding balls of 60 ‒ 120 mm diameter; balls thermal treatment line, including temperature leveling facility, quenching machine and tempering furnace. The system of the process automation enables to trace on-line all the technological parameters for production quality products, parameters of the environment to increase the energy efficiency of the section, and control system to create safety working area at the section. Within a year after the ball-rolling mill commissioning, the whole nomenclature series of balls was mastered and the passport productivity at each profile was reached. The maximum mill productivity obtained was 22 t/h. The JSC EVRAZ NTMK mill of grinding balls of 60 ‒ 120 mm diameter production meets all the modern market requirements.

During the high hardness grinding balls production the following to the process parameters is the key requirement. The temperature and the deformation uniformity are main parameters at the high hardness grinding balls rolling. Reduction forces can be estimated by modeling, but in this case, they were determined analytically, based on the distribution of the real specific reduction force over the observed temperature fields on the surface of the ball. Revealed a significant increase in the temperature of ball during the cross-helical rolling from equator to the poles from 880 °С to 940 °С. Established temperature increase (up to 60 °C) was observed in the area of the roll flange penetration into the workpiece, where significant deformations occur. Maximum average power of rolling generated on the top of the roll flanges has been determined, which reaches 350 MPa and decreases linearly with the distance from the top of the flange of the deformation tool and is practically reduced to zero on the equator of the ball. It was shown that linear nature of the change of the specific power of rolling is in good agreement with the linear dependence of the mill roll flange growth when it is introduced into the workpiece.

The downtime of ball-rolling mills is largely associated with the replacement of worn rollers. In the present work, the degree and location of critical roller wear are studied: the greatest wear is observed at the flanges in the billet-capture zone. The conditions required for billet capture and successful rolling are determined analytically. Variation in roller speed during billet supply is proposed. Tests are conducted with linear and quadratic variation in roller speed. The familiar formulas for the mean deformation rate are modified for linear and quadratic variation in roller speed. Experiments are conducted on the ball-rolling mill of AO EVRAZ Nizhnetagil’skii Metallurgicheskii Kombinat (NTMK), in rolling 60-mm ШЗГsteel grinding balls on a 40–80 rolling mill. In the experiments, the roller speed is varied manually according to a specified program, with billet capture by the rollers. It is found that speed variation significantly affects the mean pressure at the instant of billet capture. Time dependences of the torque and the mean contact pressure are plotted on the basis of calculation results and experimental data. Empirical characteristics with linear and quadratic variation in roller speed are presented. The permissible agreement of the calculated and empirical results is determined. The installation of a thyristor converter is proposed, so as to decrease the roller speed before billet capture and restore the speed to the rated value in specified fashion after capture. That yields a uniform distribution of the mean contact pressure over the roller length during automatic operation of the mill in different conditions. As a result, the roller wear is decreased, without loss of mill productivity. That reduces roller consumption and the mill downtime for roller replacement.

Presented is the state of ball rolling production, review of existing techniques for roll pass design ball-rolling today development. Possibilities of roll pass design with regard to the existing metal cutting equipment and variation of pitch parameters. The priority is set for the use of rolling rolls with a continuously varying pitch, in comparison with rolls with discretely varying pitch. Possibility of using 5-axis milling equipment for obtaining a given profile, with several variable values, is shown. Model is developed for calculating the roll pass design for rolls with a continuously varying pitch, the save constant amounts of metall of workpiece between the rolls in every moments. Pitch change functions for roll pass design of ball rolling with a constant and variable flange width are derived, using which it is possible to determine the theoretical pitch at any rolls rotation angle. Technique for constructing a 3-D model is developed, based use on obtained curve of the 2nd order, which is the basis helical surface with a continuously varying pitch. Production of profile on a 5-axis machining center, according to the the 3D models suggest. Roll pass design was used ob the experience practical, with production example ball with a diameter of 120 mm, which were calculated from the deduced function for rolls with a constant width of the flange. He was tested in the conditions of the newly introduced ball-rolling mill of JSC "EVRAZ-NTMK". After introduction of a new roll pass design, were resived technical results: the reduction in force rolling, in contrast at use operating rolls with discretely varying pitch, by 25–30%, obtaining ball sizes that are as close to nominal values GOST standard, decreased of defects, uniformity forge along entire length of the rolls forming-part obtaining.The analytical solutions presented in this article, in combination with industrial approbation, make it possible to use a new method roll pass design rolls of a ball rolling mill with a continuously changing pitch for educational and production purposes.

Backgrounds. It is possible to obtain grinding balls production by cross-helical rolling method, with particular accuracy to their geometry. It is relevant to divide produced grinding balls nomenclature into 2 groups of geometric accuracy. It is recomend use of “particular accuracy” to balls intended for heat treatment into the fifth hardness grade. The study object is grinding balls. The research subject is process of grinding balls production on modern equipment with high geometric parameters achievement. The aim of this resurche is it structure the parameters to which accuracy of the grinding balls geometric dimensions on, determining their influence degree, as well as the maximum deviations for proposed group of high accuracy balls. Materials and methods. The study was carried out in conditions of the EVRAZNTMK JSC rail and beam workshop. Rolling was on modern ball-rolling mill 60- 120. The rolls were manufactured at 5-coordinate machining center NORMA L-45, and geometric parameters were controlling on FAROARM measuring machine. Results. Following limit of geometric accuracy were identified: the limit due to manufacturing quality of deformation tool, the limit in setting ball-rolling mill and the measurement limit. Total limit was calculated under for all sizes of obtained balls. The table with gradation of grinding balls into two groups: ordinary accuracy and high accuracy, indicating maximum deviations in size was compiled. Conclusions. The study confirms that at now it is possible to obtain increased accuracy balls, which, due to decrease in stress concentration, will be minimally subject to destruction during hardening and external influences.

The paper analyzes the effect of friction stir processing (FSP) on the structure and phase state of two titanium– nickel alloys: Ti–50.9Ni and Ti–50.2Ni (at %). The analysis shows that with the FSP modes and equipment chosen, the treatment creates no macroscopic defects in the stir zone, dissolves the initial texture of the alloys, and weakly influences their structure and phase state. In the internal volumes of the track region, Ti–50.9Ni preserves its B2 phase and Ti– 50.2Ni undergoes R → B2 transition with its B19′ phase kept intact. The oxide layer thickness is smaller than 50 µm.

The Prototyping phase of the BAIKAL-GVD project has been started in April 2011 with the deployment of first autonomous engineering array which comprises all basic elements and systems of the Gigaton Volume Detector (GVD) in Lake Baikal. The prototyping phase will be concluded with deployment of the GVD demonstration cluster “DUBNA” in 2015, which will comprise 192 light sensors arranged at 8 strings. The first stage of the GVD demonstration cluster which consists of three strings was deployed in April 2013 and successfully operated up to February 2014. We review the prototyping phase of the BAIKAL-GVD project and describe the configuration and design of the 2013 engineering array.

In April of 2013, the first stage of the experimental cluster of the NT1000 deep-water neutrino telescope consisting of three strings with 24 optical modules in each was installed at Lake Baikal and switched on in the continuous exposure mode. The detection and data acquisition systems of this setup are described.

The currently running NT200 and NT200+ Baikal neutrino telescopes and the prospects for development of the Baikal Neutrino Project are briefly descr⇊ed. Preliminary results of the search for neutrino events correlated with cosmological gamma-ray bursts at the NT200 are presented. The feasibility of developing a method for acoustic detection of ultrahigh-energy neutrinos in the Baikal Neutrino Project is discussed. The calculation results for the energy spectrum and zenith-angle distributions of atmospheric neutrinos in the energy range from 10 to 107 GeV obtained within various high-energy hadron-nucleus interaction models are presented.

A simple method of estimating spatiotemporal scales of vertical water exchange caused by the instability of the temperature profile is described. The motion of a hypothetical liquid particle with preset temperature and volume is described by a one-dimensional equation which describes an approximate model for estimating the vertical water exchange scales. An exact nonlinear expression is used for a force which acts on an immersed particle. Based on the first integral of motion, rotation points and time of motion between them are determined. The distance between the rotation points and the corresponding time period are considered as physically substantiated estimates of spatial and temporal scales of vertical water motion. These estimates are based on the fundamental principles and do not provided detailed information; however, they have general character and can be used for a description of concrete cases. The developed method is applied to the temperature profiles obtained in hydrophysical investigations with the Baikal Neutrino Telescope located in Southern Baikal.

The history, current status, and prospects for the development of the Baikal Neutrino Project are considered. The main physical results obtained with the help of NT200 and NT200+ neutrino telescopes are presented.

The main physical results obtained with the Baikal neutrino telescope NT200 during the period 1998–2003 are reviewed: the limits for the diffuse flux of high-energy neutrinos, high-energy muons, and magnetic monopoles and the results of search for neutrinos from the center of the Earth due to annihilation of weakly interacting massive particles and from local neutrino sources. In April, 2005, the neutrino telescope NT200 was extended by introduction of three new strings, located at a distance of 100 m from the NT200 center. The new deep-water complex NT200+ has an effective volume for detecting cascades from high-energy neutrinos larger than that of NT200 by a factor of 4. At a cascade energy of 10 PeV, the effective volume of the new complex is 107 m3. Further development of the Baikal neutrino experiment is related to the design and fabrication of a detector with a volume of about 1 km3.

The hydroacoustic coordinate-measuring system of the NT-200 Baikal neutrino telescope is described. It is a ranging long-base hydroacoustic system constantly operating in an automated or interactive mode and capable of measuring the coordinates of the detecting modules of the NT-200 to within 20 cm. Special attention is given to the justification of the estimate of the coordinate measurement errors. As an illustration, some results of measuring the coordinates of the elements of the NT-200 and the hydrophysical characteristics of lake Baikal are presented.

The status of the Baikal neutrino experiment is briefly reviewed and the results of the search for the natural flux of high-energy neutrinos are reported.

High-frequency noise of Lake Baikal is investigated using a submersible self-contained instrument to determine the noise background for the acoustic detection of superhigh-energy neutrinos. It is found that, under stationary and uniform meteorological conditions, the integral noise power in the frequency band 1–50 kHz is virtually independent of depth and is 10–200 mPa or more, depending on the specific conditions. The noise itself contains multiple short pulses of different amplitudes and shapes.