- TITLE:
THE DETERMINATION OF THE CAUSES FOR PREMATURE RELEASE FROM THE ARRAY OF CAST CYLPEBS MADE FROM WHITE HIGH CHROMOUS CAST IRON AND THEIR SUBSEQUENT THERMAL TREATMENT
- AUTHOR(S):
B.K. Tilabov, A.A. Muhamedov
- ABSTRACT:
This article discusses the causes of premature failure of the drum cast cylpebs made of a white high chrome cast iron LLC «Dalvarzinsky repair factory». Theoretical and practical basics of preparation and receipt of cylpebs by casting in earthen form were observed. In the article is presented the best option of the chemical composition of cast iron ICHH28N2 brand and its mechanical properties-hardness of iron, optimal thermal treatment with a double phase recrystallization for cast cylpebs are presented. The composition and properties of the iron before and after heat treatment are studied. The final heat treatment mode, increasing hardness and wear resistance of cast cylpebs in two or more times are proposed.
- TITLE:
GENETIC PROGRAM OF STRUCTURAL EVOLUTION AND SYNTHESIS OF SPINDLE-MOTOR HYBRID ELECTROMECHANICAL SYSTEMS
- AUTHOR(S):
V. Shinkarenko, Y. Kuznetsov, A. Salenko, I. Gaidaienko, E. Oleynik, O. Chenchevaya
- ABSTRACT:
The paper studies the matters of genetic models, which determine algorithms for structural synthesis of hybrid electromechanical converters of "spindle-motor" class. According to the analysis of the space admissible crosses, authors determine the genetic structurisation programs of the investigated spindle-motor class as the diversity of genetically admissible classes of spindle-motors hybrid structures. On
the basis of genetic models the structural foresight was realized and there were defined the species of spindle-motors, which are promising at this stage of technical evolution and are the subject to technical implementation.
- TITLE:
INVESTIGATION OF THE DYNAMIC BEHAVIOUR OF BEAM STRUCTURE WITH GEOMETRICAL NONLINEARITY
- AUTHOR(S):
J.T. Maximov, A. P. Anchev, V. T. Kuzmanov
- ABSTRACT:
The dynamic behaviour of straight cantilever beam has been investigated. The beam is loaded simultaneously of bending and compression, which is a reason for geometrical nonlinearity. A method for dynamic modeling of the beam elastic curve has been applied. The method is based on the idea of separation of the variables (time and metric) before establishing the differential equation of motion by
means of prior static modeling of the elastic line shape. The approach has been applied to the device for the experimental determination of the coefficient of sliding friction between the deforming element and the workpiece during the slide diamond burnishing process. The body of the device has been modeled as a cantilever beam with geometric nonlinearity. Between the longitudinal (burnishing force) and transverse
(slide friction force) forces exists a correlation defined by Coulomb's law of sliding friction. On this basis, it is obtained an analytical relationship between the deflection and the friction coefficient.
- TITLE:
DYNAMIC BEHAVIOR OF THE SYSTEM “PRINCIPAL BEAM – TELPHER – LOAD” DUE TO TELPHER MOTION
- AUTHOR(S):
V. P. Dunchev, J.T. Maximov
- ABSTRACT:
This article presents the results from an analytical study of the dynamic behaviour of the metal structure of a bridge crane due to the movement of the electric hoist. The modeled system includes: the principal beam of the crane; moving with a constant horizontal velocity hoist; elastically fixed to the hoist load. The forced vibrations with its own frequency and with forced frequency, due to the movement of the hoist, have been analyzed. A concept of "dynamic coefficient" has been introduced, which is a ratio of the dynamic deflection of the principal beam to the static one. This ratio has been compared with the known from the literature empirical coefficient of dynami sm during the hoist movement, due to unevenness the track.
- TITLE:
A STUDY OF THE NEEDS FOR TEACHERS - ENGINEERS FOR PROFFESIONAL SCHOOLS OF "TECHNICAL SCIENCE AND TECHNICAL PROFFESIONS"
- AUTHOR(S):
D. Dimova, R. Ivanova
- ABSTRACT:
The planning of the training of personnel for secondary education, particularly for vocational schools – teachers on engineering, electrics and electronics, it is necessary to estimate the demand of such personnel on the labor market at the particular moment, as well as the amounts who are to leave jobs over the next ten years due to retirement. Since no information is collected on these quantities by the National Statistical Institute (NSI) and the Employment Agency it is necessary to estimate the desired quantities using data based on the information available from these sources. Our proposed methodology is an opportunity to solve this problem.
