scholarly journals INVESTIGATION OF RELIABILITY OF THE SCREW UNIT OF THE COAL-ROLL PRESS BТ-3М

2020 ◽  
Vol 2 (440) ◽  
pp. 120-128
Author(s):  
E.S. Abdrakhmanov ◽  
B.T. Yermagambet ◽  
Zh.M. Kassenova ◽  
M. K. Kazankapova ◽  
А. Sairanbek
Keyword(s):  
Stress State ◽  
Screw Press ◽  
Specific Pressure ◽  
Equilibrium Equations ◽  
Hollow Shaft ◽  
Method Of Calculation ◽  
Calculation Of Parameters ◽  
Second Stage ◽  
Blade Thickness ◽  
Constant Section

In the article we propose the method of calculation of parameters of stress state and rigidity of screw blade at bending in one plane, screw-piston press of BТ-3М grade for production of coal briquettes is simultaneously mixing, transporting and pressing unit. The blade is regarded as a thin axially endless helicoid shell rigidly attached to the shaft along an internal helical boundary. Considering that the presence of the blade does not affect the deformation of the constant-section shaft during bending, we examine the effect of the presence of the blade on the bending stiffness of the screw. Invention covers the problem of screw blade deformations at preset displacements at inner boundary caused by shaft bending considering that its axis has curvature. In the second stage of calculation we construct a compensating solution, which eliminates inconsistencies in differential equilibrium equations and static boundary conditions, and on the inner contour of the shell we set conditions of rigid pinching. As a result, the screw was calculated using the developed method. Blade is calculated with parameters r1 = 0.04 m, r2 = 0.1 m, r3 = 0.03 m, screw blade thickness d = 0.005 m, L = 0.2 m, total length of hollow shaft 1, 2 m. Calculations have shown that at such screw parameters and created specific pressure of material on the screw Ore = 8.5 · 105 Pa, the rigidity of the blade is the stiffness 11% of the tubular shaft. Keywords: screw, press, calculation, briquette, extras, equations.

Thermal stress state of cryogenic high-pressure vessels during chilling and pressurization. Report no. 1. Method of calculation

1986 ◽  
Vol 18 (1) ◽  
pp. 87-92
Author(s):  
A. S. Tsybenko ◽  
B. A. Kuranov ◽  
A. D. Chepurnoi ◽  
V. A. Shaposhnikov ◽  
N. G. Krishchuk
Keyword(s):  
High Pressure ◽  
Thermal Stress ◽  
Stress State ◽  
Pressure Vessels ◽  
Thermal Stress State ◽  
Method Of Calculation

Research of parameters of assessment of human settlements to improve the efficiency of their fire protection on the example of fire department, Voronezh

10.12737/4947 ◽  
2014 ◽  
Vol 7 (1) ◽  
pp. 8-10
Author(s):  
Бартенев ◽  
A. Bartenev ◽  
Сербулов ◽  
Yuriy Serbulov
Keyword(s):  
Fire Protection ◽  
Fire Department ◽  
Parameters Estimation ◽  
Human Settlements ◽  
Method Of Calculation ◽  
Calculation Of Parameters

Methods of research of parameters estimation of territories of settlements. developed generalized method of calculation of parameters estimation of territories of settlements.

Effects of Specific Pressure and the Dual Refiner on Microstructure of the Squeeze-Cast 2024 Aluminum Alloy Drive Hollow Shaft

2014 ◽  
Vol 487 ◽  
pp. 153-156
Author(s):  
Cai He Fan ◽  
Yue Bing Zhu
Keyword(s):  
Grain Size ◽  
Aluminum Alloy ◽  
Mass Fraction ◽  
Squeeze Casting ◽  
Specific Pressure ◽  
Lower Mass ◽  
2024 Aluminum Alloy ◽  
Hollow Shaft ◽  
Squeeze Cast ◽  
Average Grain Size

Effects of specific pressure and the dual refiner of Al-5Ti-1B and Al-10RE on microstructure of the hollow 2024 aluminum alloy drive shaft prepared by squeeze casting in express locomotive were investigated in this paper. With the increasing specific pressure, the ɑ-A1 primary grains became rounder and smaller. With the specific pressure up to 120 MPa, the average grain size of the ɑ-A1 primary grains and the average equivalent roundness were 38 μm and 0.75 respectively. When the dual refiner was adopted, the average grain size of the alloy decreased obviously with a lower mass fraction of A1-5Ti-1B and a higher mass fraction of Al-10RE. However, no obvious change was detected in the average equivalent roundness. The roundness value ranged from 0.62 to 0.72. With the dual refiner of 1wt% Al-5Ti-1B and 3wt% Al-10RE, the average grain size of the alloy and the average equivalent roundness were 26 μm and 0.71 respectively.

scholarly journals STRESS-STRAIN STATE IN BOUNDARY LAYER OF THE CIRCULAR PLATES WITH VARIOUS THICKNESSES BASED ON THE REFINED THEORY

2020 ◽  
Vol 82 (1) ◽  
pp. 32-42
Author(s):  
Val.V. Firsanov ◽  
Q.H. Doan ◽  
N.D. Tran
Keyword(s):  
Boundary Layer ◽  
Stress State ◽  
Strain State ◽  
Three Dimensional ◽  
Refined Theory ◽  
Circular Plates ◽  
Equilibrium Equations ◽  
Stress Strain ◽  
Stress Strain State ◽  
Three Dimensional Elasticity

A variant of the refined theory on calculation of the stress-strain state of circular plates with symmetrically various thicknesses according to an arbitrary law in the radial direction was presented. Equations of the plate state were established by using the three-dimensional elasticity theory. The required displacements were approximately calculated according to upright direction to the middle plane by polynomials with two degrees higher than in the classical Kirchhoff - Love theory. The differential equation at equilibrium in displacements with various coefficients was obtained by using means of the Lagrange variational principle. The direct integration of the equilibrium equations in the three-dimensional elasticity theory was used to determine the transverse normal and shear stresses. Of an isotropic circular plate with changing in thickness by using the analyzing Fourier chain, the obtained differential equilibrium equations in displacements with variable coefficients containing supplement components and taking into account of the effect of thickness on the stress-strain state of the plate. Examples of calculating the stress state of a circular plate with a thickness varying according to linear and parabolic laws under the action of a uniformly distributed load were considered. The limited difference method was employed to solve the boundary value problem. Comparison results of the refined and classical theories were investigated. It is demonstrated that the study on the stress state in the zones of its distortion (compounds, local loading zones, etc.) should use a refined theory, since the additional corresponding stresses of the “boundary layer” type are of the same order with the values of the main (internal) stress state. This is important to increase the reliability of strength calculations of such elements of aircraft-rocket structures as the power housings of aircraft, their various transition zones and connections, as well as objects in various engineering industries.

THE DYNAMIC ANALYSES AND VERIFICATIONS OF A HOLLOW SHAFT WITH HOT-FIT COMPONENT USING 3D FINITE CONTACT ELEMENT

2013 ◽  
Vol 37 (1) ◽  
pp. 21-38 ◽  
Author(s):  
Shin-Yong Chen
Keyword(s):  
Stress State ◽  
High Speed ◽  
Contact Element ◽  
Modal Testing ◽  
Engineering Practice ◽  
Stressed Condition ◽  
Theoretical Formulation ◽  
Hollow Shaft ◽  
Rotor Shaft ◽  
Key Factor

In general engineering practice, one key factor in designing a motor built-in high-speed spindle is to assemble the motor rotor and shaft by means of hot-fit to form a new rotor-shaft assembly. In this paper, the dynamic analysis of a hot-fit rotor in a rotor-shaft assembly by using 3D contact element is proposed. Contact pressure between the rotor and the shaft is firstly calculated through contact theory. The stress state is thus determined. The finite element modal analysis then follows with the stress state as a pre-stressed condition. The accuracy and the validity of the finite contact element results are verified by theoretical formulation, equivalent static analysis and experimental modal testing. The results presented herein indicate that it is accurate and effective in analyzing the dynamic behavior of the rotary shaft system with a hot-fit component by using contact element.

Comparison of 2D and 3D Airfoils in Combination With Non Axisymmetric End Wall Contouring: Part 1 — Experimental Investigations

2016 ◽  
Author(s):  
Tobias W. Zimmermann ◽  
Oliver Curkovic ◽  
Manfred Wirsum ◽  
Andrew Fowler ◽  
Kush Patel
Keyword(s):  
Gas Turbines ◽  
Experimental Investigations ◽  
Test Rig ◽  
Second Stage ◽  
Beneficial Impact ◽  
Flow Phenomena ◽  
2D And 3D ◽  
End Wall ◽  
Constant Section ◽  
Turbine Blading

Tangential end wall contouring is intended to improve turbomachinery blading efficiency. This paper is the first of a series of two papers. It summarizes the experimental investigation of a test turbine with end wall contoured vanes and blades. Constant section airfoils as well as optimized 3D high pressure steam turbine blading in baseline and end wall contoured configurations have been examined in a 2 stage axial turbine test rig at the Institute of Power Plant Technology, Steam and Gas Turbines (IKDG) of RWTH Aachen University. The test rig is driven with air. Brush seals are implemented within the casing sided cavities to minimize the leakage flow near the tip end walls, where the contouring is also applied. The pressure and temperature data that is recorded in three axial measuring planes are plotted to visualize the change in flow structure. This has shown that the efficiency is increased for 2D airfoils by means of end wall contouring, which is caused by a homogenized inflow to the second stage. However the efficiency of the first stage suffers, the end wall contouring is beneficial for the performance of the engine. Both phenomena (an efficiency loss in stage one and an improvement of the performance in stage two) have also been measured for the optimized 3D configurations thus it can be expected that end wall contouring has also a beneficial impact on the performance of multi row turbines. The second part of this paper presents the results of numerical investigations of end-wall contoured blades. It will demonstrate how the secondary flow phenomena are influenced by end-wall contours. The simulations are validated with measured data from the test rig.

scholarly journals Methods and results of long-term strong earthquakes forecast in the Uzbekistan territory

2021 ◽  
Vol 929 (1) ◽  
pp. 012028
Author(s):  
T U Artikov ◽  
R S Ibragimov ◽  
T L Ibragimova ◽  
M A Mirzaev ◽  
Y L Rebetsky
Keyword(s):  
Stress State ◽  
Strong Earthquake ◽  
Occurrence Probability ◽  
Analysis Method ◽  
Strong Earthquakes ◽  
Seismic Regime ◽  
Second Stage ◽  
Active Structures ◽  
Active Zones

Abstract An approach to evaluate the current seismological situation in the Uzbekistan territory is presented. This approach is based on the regularities of seismic processes in strong-earthquake focal areas and the manifestation peculiarities of strong earthquakes in seismically active zones. At the first stage, within seismically active zones, areas with a high seismic activity matching the strong earthquake level were identified during the historical and instrumental observation periods. Considering the low variability in the direction of seismotectonic processes over tens and hundreds of years, which determines the modern stress state of seismically active structures, these areas were considered the most likely areas to experience strong earthquakes over the next few decades. Tectonophysical validation of the division of seismically active zones into areas with different potential hazards of strong earthquakes was carried out within the framework of cataclastic analysis method of rupture dislocations (CAM). At the second stage, temporal fluctuations in seismic regime parameters within the selected areas were studied. Based on the number of current anomalous features identified, the areas were ranked according to the occurrence probability of strong earthquakes over the next few years.

scholarly journals Algorithm for calculation of channel deformation in soils of various graininess

2018 ◽  
Vol 251 ◽  
pp. 02006
Author(s):  
Anna Hodzinskaya
Keyword(s):  
Laboratory Experiments ◽  
Block Diagram ◽  
Coarse Grained ◽  
Method Of Calculation ◽  
Calculation Of Parameters ◽  
Slight Excess ◽  
Channel Deformation ◽  
Mean Diameter ◽  
Uniform Particle Size ◽  
Good Agreement

The article deals with deformations of channel beds in of various-grained, non-cohesive, rather coarse-grained soils having more than 0.55 mm mean diameter of particles that might form natural pavement at velocities slightly higher than non-erosive ones. Laboratory experiments prove that as soon as natural pavement has formed, modelled bed deforms only a little. Is proposed scheme of calculation of parameters of the channel and the channels deformation. The bed should be erosion normally of the slopes. To estimate the time of deformation is proposed to use for the flow of the bottom sediments of probabilistic formulas, based on a model of K. I. Rossinskii. To determine the diameter of armoring and depth of erosion of the riverbed of the proposed new method of calculation that gives the values close and experienced and method of A.V. Magomedova. Is given block diagram of the calculation riverbed in a non-uniform particle size. Channels sizes you can define by setting a slight excess permissible velocities, or you can take specified values. There is good agreement between the values of erosion obtained in the experiments and in the calculations. In the presence of the surface layer of the slope or the ballast layer of geotextile of various-grained of a certain thickness may be formed armoring, capable of protecting the slopes of the channel from erosion.

Torsional stress state in a hollow shaft with longitudinal slots

1977 ◽  
Vol 9 (2) ◽  
pp. 189-192
Author(s):  
V. I. Savchenko ◽  
T. Yu. Kepich ◽  
E. M. Grebelyuk ◽  
V. G. dokuchaev ◽  
L. Ya. Usherenko
Keyword(s):  
Stress State ◽  
Torsional Stress ◽  
Hollow Shaft
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