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11.06.2019

Новую книгу профессора Александра Анисимовича Скоромца, профессора В. В. Афанасьева, профессора А. П. Скоромец и профессора Т. А. Скоромца "Сосудистые заболевания спинного мозга" (руководство
для врачей) издательство "Политехника" выпустило к XI Всероссийскому съезду неврологов и IV Конгрессу Национальной ассоциации по борьбе с инсультом, которые пройдут с 15 по 19 июня 2019 г. Экспофоруме Санкт-Петербурга.

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06.06.2019

Пост-релиз

Итоги выставки «Металлообработка-2019»

С 27 по 31 мая 2019 года в Москве в ЦВК «Экспоцентр» проходил один из крупнейших промышленных смотров в мире – 20-я международная специализированная выставка «Оборудование, приборы и инструменты для металлообрабатывающей промышленности» – «Металлообработка-2019».

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04.06.2019

В СПбГМТУ прошло внеочередное совещание рабочей группы по двигателю ПД-35

Морской технический университет посетила делегация, в составе которой - представители компаний, входящих в рабочую группу по двигателю ПД-35, в том числе, филиал АО «ОДК» НИИД, ПАО «ОДК-Сатурн», ФГУП «ЦИАМ им. П. И. Баранова», ПАО «Кузнецов», ПАО «ОДК-УМПО», ФГБОУ ВО «ПНИПУ», АО «ЦАТ», ФГУП ВИАМ, АО «ОДК-Авиадвигатель».

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15.05.2019

Уважаемые читатели, ждем Вас на выставке!
С 23 по 26 мая 2019г. в Михайловском манеже Санкт-Петербурга пройдет XIV Международный Книжный Салон.

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17.12.2018

Издательство «Политехника» представляет фундаментальное издание

«Традиционная китайская медицина. Искусство иглоукалывания и прижигания»

в трех томах (общим объемом 213,5 усл.-печ. листов).

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05.12.2018

По многочисленным запросам наших читателей в издательстве "Политехника" выходит 4-е издание книги "ЗАСЛОН НА РЕКЕ ТОСНЕ".

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Принимаем к оплате
Потапов, А. С. Искусственный интеллект и универсальное мышлениеСвистунов В. М., Пушняков Н.К. Отопление, вентиляция и кондиционирование воздуха объектов агропром

Metalloobrabotka № 1 (109)/2019

Metalloobrabotka № 1 (109)/2019
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Цена: 700 Руб.


Pereladov A. B. Experimental study of the grinding of difficult to machine materials

Researches of process of grinding of difficult-to-process materials (tool steels) by the abrasive tool with various characteristics are described. The purpose of the research is to conduct a physical experiment to assess the performance of the designed grinding tool from abrasive grain of 25A grade on the organic (bakelite) bond, to establish the influence of grinding modes and characteristics of the tool on the process output and processing quality. Researches were carried out within complex tests for improvement of the existing model representations and methods of numerical calculation of operations of grinding, development of means of the automated design of the tool and technologies of its application.

Keywords: grinding, hard-to-work materials, organic bond, assessment of working capacity

Kim V. A., Mokritsky B. Ya., Yakubov Ch. F. Аnalysis of the shear plane during sheet forming in the cutting process. Part 1

The efficiency of the cutting process blade tool depends largely on how and what processes occur in the cutting zone, in particular, in the shear plane. The nature of the deformation processes occurring in the shear plane determines the efficiency of the chip formation process, the nature and level of contact-friction interaction. By controlling the process of chip formation, it is possible

to create conditions for maintaining the technological cutting system in a favorable energy and dynamically stable condition. Due to the non-linear nature of the processes there are many unstable States, which are characterized by a certain combination of the level of critical cutting conditions,

the state of the cutting tool. Self-organization of unstable States of a nonequilibrium system leads to the development of dissipative structures that increase the dynamic stability of the system itself.

The functioning of dissipative structures is aimed at minimizing the absorbed internal energy and restoring the imbalance between the external influence and heat flows. The paper shows that the shear plane is a simplified representation of the zone of active deformation processes of chip formation, and performs an important function in the synergetic algorithm of the metal cutting process. The boundary of the plastic shear zone is determined by a numerical complex including the shear modulus, plastic deformation potential and yield strength. The position of the shear plane depends on the cutting conditions, physical and mechanical properties of the processed material and its tendency to deformation hardening, and determines the shrinkage and chip type, as well as provides a minimum of energy costs for the deformation process of chip formation.

Keyword: self-organization, dissipative structures, plastic deformation.

Kim V. A., Mokritsky B. Ya., Yakubov Ch. F. Аnalysis of the shear plane during sheet forming in the cutting process. Part 2

The hypothesis is stated that the cutting system for the effective chip formation process requires the same intensity of plastic deformation as for the shear in the hardened material, but the geometry of the deformation zone must be changed so as to ensure the shift of the material at the yield point to shear in the region of the nonstrengthened (or less hardened) material. It is established that: 1) chip formation is an unstable process, since the deformation hardening causes a shift not on one constant plane of shear, but on different planes within the possible range of shear angle change as a parameter of adaptation of the technological cutting system with the maximum tendency to chip formation stability; 2) the possibility of the least kinematic variability of chip formation is characteristic of small positive front cutting angles, which coincides with the recommendations of researchers on the choice of the front angle for cutting with a minimum intensity of wear and ensuring the drain chips. The more strain hardening, the more minimal the range of variation of the angle of inclination of the plane of shear; 3) in case of negative front angles to the cutting capabilities of the system of cutting to carry out adjustment by changing the plane of shear is limited.

Keywords: self-organization of chip formation, change of position and length of shear plane during cutting.

Ogorodov V. A. Analysis of methods of clamping of thin-walled cylinders at honing

The analysis of ways of clamping the thin-walled cylinder with a stepped shape of the outer surface, the basis of the analysis allowed the study of the distribution of the radial cutting forces along the machined hole in one double stroke of the honing bars. All the variety of stepped thin-walled cylinders is presented in the form of six standard samples, the relative sizes of which correspond to the real details, which differ only in the number of stiffeners, their size and location. The diagrams of radial forces in relation to the four most commonly used in the practice of honing methods of clamping the workpiece: the flange; clamp at the ends; fixing the axial tensile force; clamp on the outer surface with a rubber cuff (diaphragm). The radial cutting force diagrams are

calculated for two lengths of honing bars, the length of which is 0.75 and 1.0 sample lengths. Keywords: honing, method of fastening, thin-walled cylinder with a step shape of the outer surface, the plot of the radial cutting forces, a typical sample, deformation, clamping at the ends, fixing the axial tensile force, diaphragm device, deviation of the hole shape, analysis of ways of fixing the workpiece, the length of the honing bars.

Vinnik P. M., Vinnik T. V., Olekhver A. I., Remshev E. Yu. Calculation of the effect of hardening material on stresses and generated mechanical properties at the successive drawings with wall thinning

When drawing with thinning of the wall, uneven hardening of the material of the wall of the product occurs, that is, the yield stress across the wall thickness becomes variable. The article calculated the effect of this uneven hardening on stresses and degrees of deformation during subsequent extracts with wall thinning. It is shown that in practical calculations, the influence of the variability of the yield stress over the wall thickness is insignificant, and it can be neglected. Keywords: drawing with wall thinning, hardening, rate of strain.

Korotkich M. T., Polubok K. A. The article discusses the technological capabilities of machining gears by wire EDM cutting

It is shown that, despite the low productivity compared with traditional processing methods, in single and smallscale production conditions, the method can be economically viable. Comparative analysis of the required accuracy of gears and the accuracy of modern EDM machines shows the possibility of obtaining this method of wheels up to 4 degrees of accuracy. Studies have shown the lack of influence of the method on the reduction of the flexural strength of teeth processed by electro-erosion cutting.

Keywords: gear wheels, EDM cutting, tooth strength, performance, small-scale production.

Duradji V. N., Kaputkin D. E., Duradji A.Y., Kaputkina N.A. Electrolyte plasma processing of bimetals

Electrolyte plasma processing is high-effective and environment-friendly method to treat surfaces of metals and alloys and can be used for heat or thermochemical treatment as well as for cleaning or polishing of metal surfaces. This article describes modes to be established at the active electrode during the anodic process, and application of these modes to various types of treatment of bimetals. It is shown that there exists an option of separate or simultaneous heat or thermochemical treatment, as well as polishing of one or both surfaces of bimetals.

Keywords: electrolytic plasma, Discharge, Electrolysis, Cleaning, Coating.

Razhikov V. N., Belyaev A. N. The features of the manufacture and assembling of K-H-V planetary gear

The article contains the main technological problems, the solution of which was necessary for the development of a K-H-V planetary gear that meets the high requirements of space technology in the terms of reliability, durability, load capacity, accuracy, and torsional stiffness. A selection of materials of parts and their heat treatment, methods of mechanical processing and production control, assembly sequence, intermediate and output control were carried out. The drawings of parts and assembly units, as well as a gradual process of assembling the transmission are presented.

Keywords: K-H-V planetary gear, space technology, manufacturing and assembling technology.

Smetanin S. D., Shalamov V. G., Plaxin A. V. Determinationof geometrical parameters of the cutting blade of the rotary mill

Cutting conditions are determined by the kinematic angles of the tool. Unlike most traditional, in rotary tools, static angles significantly differ from kinematic ones. Existing methods do not allow you to write geometric parameters of tools in full compliance with the definition approved in the standard. The proposed method makes it possible to determine the direction of the resultant velocity from geometric relationships in accordance with the design scheme that reflects the kinematics of rotary milling. The adequacy of the developed methodology was evaluated by comparing the results obtained with both the existing Bobrov’s method and with graphical constructions in the computer aided design system.

Keywords: rotary milling, angles of the tool, cutting blade.