Development of vibration system for decreasing of intensity of steel ladle outlet channel tightening

2021 ◽  
Vol 77 (2) ◽  
pp. 165-174
Author(s):  
S. P. Eron’ko ◽  
E. A. Ponamareva ◽  
E. S. Tsykhmistro
Keyword(s):  
Machine Building ◽  
Flow Section ◽  
Steel Ladle ◽  
General View ◽  
Technical Solution ◽  
Test Model ◽  
Outlet Channel ◽  
Hard Particles ◽  
Oscillation Process ◽  
Vibration Impact

The problem of tightening of outlet channel of steel ladle still remains relevant at present. A review of scientific and technical studies, aimed at elaboration of methods to keep the channel flow section constant presented. An analysis of deposition forming mechanisms on walls of outlet channel of steel ladle was done. To prevent their formation it was proposed to apply a vibration impact on the ladle shutter. Using simulation studies and specially elaborated methodology, the degree of influence and frequency of amplitude oscillations, acting along the ladle channel, on increasing speed of layer thickness formation on its walls and number of tearing off hard particles was established. To evaluate intensity of elastic waves absorption by the refractories of ladle shutter during vibration impact on it, a natural experiment was done. As a result of the experiment an initial information was obtained for determining parameters of oscillation process to guarantee effective functioning of the proposed casting facility. A necessity was established to account tenfold decrease of vibration acceleration during propagation of elastic wave along the casting channel from the lower end of collector nuzzle to the upper end of the ladle casting nozzle. Results of the complex studies became base of technical solution at elaboration of design of the ladle shutter. The elaborated shutter is equipped by a system of exciting vertically-directed oscillations, promoting decreasing intensity of hard particles sticking on the walls of the outlet channel. The design of the perfected ladle shutter and general view of its test model shown, which is equipped with the vertically-directed oscillations exciting system. Depending on capacity of the steel ladles, which can be from 100 to 300 t, their shutters can be equipped with one or several pneumatic plunger vibrators. Each of the plunger having the mass of 0.8 kg, can develop an impact force up to 300 N when supplying into its working cavity compressed air of 0.2 MPa pressure at flow rate 150 l/min. Industrial tests of the modernized shutter in a foundry shop of Yasinovatsky machine-building plant were done.

scholarly journals DESIGN IMPROVEMENT AND OPERATION MODELING OF EAF GAS EXHAUST SYSTEM OF A FOUNDRY SHOP

2019 ◽  
Vol 62 (1) ◽  
pp. 34-41 ◽  
Author(s):  
S. P. Eron’ko ◽  
S. M. Gorbatyuk ◽  
M. Yu. Tkachev ◽  
E. V. Oshovskaya
Keyword(s):  
Exhaust System ◽  
Machine Building ◽  
Technical Solution ◽  
Smoke Movement ◽  
Outlet Channel ◽  
Total Load ◽  
Industrial Sample ◽  
Dust Emissions ◽  
Working Zone ◽  
Arc Furnaces

As a result of a survey of gas exhaust systems of low-tonnage electric arc furnaces (from 3 to 10 tons) operated in the foundries of machine-building enterprises, the bottlenecks were identified, due to which a large amount of gas-dust emissions gets into the production rooms and pollutes the air in the working areas. First of all, it occurs due to the design schemes imperfection of the evacuation systems of gas and dust ejected from the furnace cavity through the outlet channel, the working window, gaps between its body and the roof, between edges of the holes in its upper part and the electrodes lowered through them. In particular, joint units of the rotary collection hoods with the gas exhaust pipelines in these systems do not provide proper sealing of movable joints. In this regard, the authors have proposed an improved design of rotation mechanism of the furnace collection hood, which involves the use of two sand gates. These gates eliminate the possibility of harmful emissions release between movably connected elements of the system into the environment. To begin designing of the industrial sample of a modernized mechanism, a method for calculating the energy-power parameters of its drive has been developed. A preliminary validation of the correctness of the taken technical decisions and of the obtained calculating dependencies was performed on the operating model of the investigated system manufactured on a 1:10 scale relative to the industrial sample. For the model research an instrumentation complex that included strain gauge transducer, AC amplifier, analogto-digital converter and computer was used. During this research the load acting on the model drive of the collection hood rotation mechanism when it was transferred from the working position to the parking one and back was fixed. At the same time, the load was measured for two cases: in the absence and in the presence of sand in the gates which ensure sealing of the movably joint elements of the investigated mechanical system. It was established that the portion of resistance forces arising in two sand gates during relative rotation of the moving element is 20  –  26  % of total load on the mechanism drive depending on angular velocity of the cantilever with collection hood. Similarly, this indicator calculated from obtained theoretical dependences was in the range of 17  –  23  % for the rotation mechanisms of collection hood of arc furnaces with a tonnage of 3 to 10  tons. Video filming of the smoke movement patterns, which flows from the furnace model through the existing gaps between its body and roof during the steelmaking process imitating, confirmed the reliability of the sand gates that provide complete sealing at the joint units of the moving parts of the collection hood rotation mechanism. Practical use of the proposed technical solution allows increasing of efficiency of evacuation of the harmful gas and dust emissions from the working zone of smelting furnaces used in the foundry.

scholarly journals An interlocking side mill with retrofittable carbide blades for processing of coarse-pitch tooth wheels

2018 ◽  
Vol 224 ◽  
pp. 01051
Author(s):  
Evgeniy V. Artamonov ◽  
Vitaliy V. Kireev ◽  
Vitaliy A. Zyryanov
Keyword(s):  
Hard Alloy ◽  
Metal Cutting ◽  
Positive Impact ◽  
Cutting Tools ◽  
Machine Building ◽  
Building Industry ◽  
Technical Solution ◽  
Straight Line ◽  
Wear And Tear ◽  
Quality Tool

Nowadays Russian manufacturers of metal-cutting tools for machine-building industry do not offer structures of prefabricated cutting hobs with retrofittable carbide blades for processing of tooth wheels, though usage of retrofittable carbide blades allows to increase significantly working capacity and productivity of the processing. As of today creation of an assembly cutting tool for processing of tooth wheels with the retrofittable carbide blades is a big step forward for machine-building industry. A high quality tool allows warranting for a new equipment and making work of operators more productive. This paper offers a new technical solution providing increase of efficiency of processing by assembly tools with the retrofittable carbide blades made of a hard alloy. Due to usage of progressive cutting patterns division of a margin for straight-line segments and curved sections is performed. This division has a positive impact on cutting hard-alloy inserts and also reduces their wear and tear.

Development of Steam Chest With Valve for Steam Extraction in Cogeneration

2014 ◽  
Author(s):  
Zhenzhen Hao ◽  
Puning Jiang ◽  
Xingzhu Ye ◽  
Gang Chen ◽  
Yifeng Hu ◽  
...  
Keyword(s):  
Flow Field ◽  
Pressure Distribution ◽  
Fourier Transforms ◽  
Operating Conditions ◽  
Mode Analysis ◽  
Technical Solution ◽  
Test Model ◽  
Aerodynamic Forces ◽  
Valve Disc ◽  
The Impact

Cogeneration has been identified as a key technical solution to improve environment, by reducing the impact of global climate change and reducing local emissions, such as particulates, sulphur and nitrogen oxides. In cogeneration, a certain pressure of steam has to be extracted from steam turbine. A mechanical device shall be used to maintain the pressure of the extracted steam. In this paper a new steam chest with valve used for cogeneration which is installed in the steam flow is introduced. Different amount of steam extractions need different valve openings. In order to obtain these several valve openings in typical operating conditions, CFD-program is used to simulate the flow path in the steam chest. The pressure distribution on the surface of valve disc can be calculated through CFD method, and corresponding steady aerodynamic forces and torques can be calculated by integral. Pulsatile flow will change the forces and moments acting on the valve discs with time constantly. Frequency spectrograms of the aerodynamic forces are obtained by using the fast Fourier transforms and compared to the characteristic frequencies of the valve disc obtained by mode analysis. For the purpose of validating the accuracy of CFD model, a test with test model scale of 1:5 has been designed. In the test, the pressure distribution on the valve disc surface and the flow field in the steam chest are acquired respectively by the method PSP (Pressure-Sensitive Paint) and PIV (Particle Image Velocimetry). CFD calculations and experimental results have been compared and it is shown that CFD calculations using K-ε turbulence model has satisfactory precision to calculate the pressure distribution, flow field and the torques.

scholarly journals Dynamic activity of military transportation investigation at the construction site

2019 ◽  
Vol 1 (52) ◽  
pp. 154-159
Author(s):  
Olena Mykhailovska ◽  
Tetiana Nesterenko
Keyword(s):  
Theoretical Data ◽  
Residential Building ◽  
Measured Data ◽  
Building Structure ◽  
Construction Site ◽  
Dynamic Activity ◽  
Factors Influencing ◽  
The People ◽  
Oscillation Process ◽  
Vibration Impact

In the paper it is confirmed that any theoretical data inferior to precisely measured data due to the impossibility ofconsidering all the factors influencing on the oscillation process. The fluctuations magnitude of a non-residential building inPoltava and the dynamic influence on the building structure and the people who can be there periodically are experimentallyinvestigated. To evaluate the vibration impact, it is necessary to compare measured data with the permissible level ofvibration in public buildings. The recommendations for the further building exploitation are based on the building structuresvibration acceleration measurements results.

Prospects of small capacity ca sting ladles transfer to stopperless casting of steel

2020 ◽  
Vol 76 (8) ◽  
pp. 803-809
Author(s):  
S. P. Eron'ko ◽  
M. Yu. Tkachev ◽  
E. A. Ponamareva ◽  
E. V. Oshovskaya
Keyword(s):  
Normal Mode ◽  
Slide Gate ◽  
Practical Experience ◽  
Machine Building ◽  
Air Cooling ◽  
Long Distance ◽  
Outlet Channel ◽  
Mechanical Destruction ◽  
Gate System ◽  
Small Capacity

Despite encouraging results, obtained at pilot tests, attempts to substitute the stopper facilities by sliding gates at casting ladles of small capacity, used at foundries of machine-building plants, did not result in their implementation in industry. The problems of transferring casting ladles with a capacity of up to 10 tons to continuous casting of steel, due to the peculiarities of their operation under conditions of obtaining low-weight castings, were considered. Priority problems were noted, the successful solution of which will confirm the prospects of using slide gates in foundry. The main requirements for a steel tapping gate system of a casting ladle of small tonnage are as follows: autonomy of the power supply of the shutter drive, eliminating the need to move flexible hoses over a long distance along the working platform; guaranteed start of casting in normal mode without burning the channel with oxygen; the stability of the node pressing the refractory plates of the slide gate to high temperatures in the absence of forced air cooling; the possibility of an active influence on reducing the intensity of the process of overgrowing of the steel outlet of the ladle in the course of filling molds. As a constructive solution aimed at fulfilling the indicated conditions, it was proposed to use a balancer-type cartridge valve equipped with a modernized electromechanical actuator and auxiliary devices for starting casting in normal mode due to mechanical destruction of the crust at the entrance to the steel outlet channel, as well as heating its walls in the closed state when moving the ladle from one form to another. It was recognized that participation on a parity basis in the creation of a promising sliding gate system for foundry ladles with a capacity of up to 10 tons of several development organizations with practical experience in this technical field is worthwhile.

scholarly journals Improving Gear Milling Efficiency by Creating Prefabricated Cutters with Replaceable Cutting Carbide Plates

2020 ◽  
Vol 24 (1) ◽  
pp. 35-51
Author(s):  
E. V. Artamonov ◽  
V. V. Kireev ◽  
V. A. Zyryanov
Keyword(s):  
Metal Cutting ◽  
Cutting Tools ◽  
Machine Building ◽  
Initial Contour ◽  
Technical Solution ◽  
Processing Efficiency ◽  
Milling Cutter ◽  
Cutting Insert ◽  
Metal Cutting Tool ◽  
Building Enterprises

Today, when machining domestic-made worm milling cutter according to GOST 9324-80, a problem arises in their durability at the roughing stage. Russian tool companies engaged in the manufacture of metal cutting tools do not currently offer prefabricated worm tools with cutting elements made of hard alloy tools for machining large-modular gears.Purpose of research. Creation of prefabricated structures for machine-building enterprises with replaceable cutting carbide plates (RCHAP). Due to this, the productivity of equipment already available at the enterprise is increased several times, the economic efficiency of introducing high-quality metal-cutting tools makes it possible to purchase modern equipment and make the work of machine operators at machine-building enterprises more efficient and less time-consuming. In this paper, we propose a fundamentally new technical solution, which makes it possible to increase the efficiency of machining gears with a metal-cutting tool, with the arrangement of replaceable carbide cutting plates in the prefabricated initial contour of the manufacturing rail in worm milling cutters.Methods. The research method is the use of graphic simulation, which allows you to determine the size of the crosssectional area of the cut layer for the cutting elements of the worm tool.Results. Improving the processing efficiency will be achieved by implementing a group cutting scheme in a prefabricated worm milling cutter by using a larger number of main and side carbide cutting inserts on an Archimedean tool worm, which allow sequentially cutting the machining allowance and reducing the feed rate to the cutting insert, to ensure milling uniformity throughout the processing stage, and also reduce the magnitude of shock loads on cutting carbide elements of a precast tool.Conclusion. The use of replaceable carbide plates in a group cutting scheme increases the durability and reliability of a precast worm cutter.

IMPROVEMENT OF DETAILS CONNECTION ASSEMBLY TECHNOLOGY WITH INTERFERENCE

2016 ◽  
Vol 1 (2) ◽  
pp. 30-34
Author(s):  
Коновалов ◽  
Vladimir Konovalov ◽  
Симанин ◽  
Nikolay Simanin ◽  
Петрова ◽  
...  
Keyword(s):  
Fluid Pressure ◽  
Hydraulic Cylinder ◽  
Machine Building ◽  
Technical Solution ◽  
Mechanical Assembly ◽  
Interference Fit ◽  
Press Fit ◽  
Axial Forces ◽  
The Press ◽  
Assembly Technology

The purpose of the study is to increase the strength of the collected compounds and to expand the technological accuracy of the method of Assembly with an interference fit. Fixed press-fit connection with interference are widely used in machine building, when the transfer of substantial axial forces are required, torques or combined loads from their joint action. Resistance to mutual misalignment of the parts in these compounds is created and supported by the forces of elastic deformation on the mating surface of the covered part (shaft) and stretching on the mating surfaces of the covering parts (holes) is proportional to the magnitude of the preload in the connection. In such compounds, the diameter of the shaft before Assembly is always larger than the diameter of the hole. In the article the analysis of the known different ways of joining parts with interference fit, including hydraulic presses. The second problem is solved due to the fact that the connection details with tightness is carried out by pressing the press stroke from one detail to another, and the breakdown of the compounds obtained by the relative longitudinal movement of parts, in which the breakdown is carried out periodically in the process of pushing through the transfer of force from the press stroke to pressed items to the elastic connection. The force on the press stroke is created by a hydraulic cylinder with large displacement, a resilient connection between the slider and pressed item performs in the cylinder, the fluid pressure and volume which can be adjusted by changing the stiffness and capacity of the drive RAM, as well as the magnitude of its longitudinal movement during the disruption. The scheme of Assembly of the connection de-hoist with tension. Original technical solution for press fit connection parts extends the technological possibilities of the equipment, increases the strength of the collected compounds and can be used in machine building, particularly in mechanical Assembly processes and, in particular, in the repair and production of agricultural machinery.

Statistical Study of the Rotation Effect of Am Stars

1976 ◽  
Vol 32 ◽  
pp. 675-683
Author(s):  
Keiichi Kodaira
Keyword(s):  
Statistical Study ◽  
Rotation Velocity ◽  
General View ◽  
Slow Rotation ◽  
Rotation Effect

SummaryExcess of [m1] index of Am stars, relative to normal stars, is statistically found to be correlated with rotation velocity; the coefficient is estimated at ∆׀m1׀ /∆V(km/sec) ˜ - 0.0007 among Am stars. This result supports the general view that slow rotation is essential for Am phenomena.

New crash test model

Nature ◽  
2001 ◽  
Author(s):  
Philip Ball
Keyword(s):  
Crash Test ◽  
Test Model
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