RU2439524C2 - Centrifugal test setup itsu40 - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention refers to test setups, and namely to drop-impact test setups. Test centrifugal setup (TCS) includes the base, working chamber with a cover, lower drive with plates on the ends of which the tested samples are arranged, which differ by the fact that on the cover there arranged is upper drive with opposite rotation direction to lower drive; at that, on the shaft end of bearing assembly of upper drive there arranged is acceleration bowl with tubes, and steam supply tube is passed through the cover to acceleration bowl in which blades are arranged parallel to rotation axis.

EFFECT: increasing the investigated speeds of impact of steam particles with the sample.

2 cl, 4 dwg

Description

The invention relates to testing machines, and in particular to drop-impact testing installations.

Known drop-impact test installations [1, 2, 3], adopted by us as analogues. Of the selected analogues, the closest in technical essence is the installation [1], adopted by us as a prototype.

The proposed installation includes a base; a chamber with a lid; drive unit; bearing assembly with a shaft on which the coupling is fixed with a plate placed in it, at the ends of which the test samples are fixed in one position. The installation is also equipped with a steam generator, devices for heating and evacuation.

Installation works as follows.

At a given temperature and vacuum, the drive is switched on and the samples fixed at the ends of the plates are accelerated to a given speed. Using a steam generator, steam is supplied to the chamber and the effect of the process of collision of vapor particles on the sample and the effect of collision on the metal structure of the sample are investigated. The disadvantages of the design of the prototype include the fact that in order to obtain high speeds of collision (150-500 m / s) of the sample with particles of steam, the installation must be large, about two meters or more in diameter.

If we are talking about working at speeds close to real for steam turbines, i.e. 300-700 m / s, then the dimensions of the installation will increase significantly, which will cast doubt on the very possibility of manufacturing an installation of such dimensions. The present invention will eliminate the noted disadvantage of the prototype and significantly increase the investigated speed of collision of the vapor particles with the sample.

The invention is illustrated in figure 1, which shows a diagram of a test centrifugal installation:

1 - base; 2 - a working chamber; 3 - lower electric motor; 4 - lower bearing assembly; 5 - coupling; 6, 7 - plates; 8, 9 - samples; 10 - top electric motor; 11 - upper bearing assembly; 12 - steam generator; 13 - steam supply tube from the steam generator; 14 - crane; 15, 16 - steam distribution tubes; 17 - condensate drain pipe; 18 - crane; 19 - the blade of the steam generator; 20 - cover; 21 - accelerating bowl; 22, 23 - capacitors; 24 - pump; 25 - tube for supplying fluid from the capacitors to the pump.

The principle of operation of the installation.

Two samples 8 and 9 are fixed at the ends of the plates 6, 7 with the lid 20 open, after which the lid 20 closes. If necessary, heating and vacuum are provided in chamber 2. The electric motor 3 is turned on and samples 8 and 9 rotate at a given speed, for example, clockwise. Then, the upper drive electric motor 10 is turned on and the valve 14. The steam from the steam generator 12 passes through the tube 13 to the accelerator bowl 21, then through the tubes 15, 16 and at the exit from the tubes 15, 16 it enters samples 8, 9. According to the principle of classical addition of speeds vapor particles fall on the plane of the test sample with an additionally increased speed. Thus, in the present invention, the collision rate of vapor particles on the samples significantly increases, which will reduce the size and weight of the installation. The installation provides for a closed cycle of fluid circulation. Water flows through the tubes 18 to the condensers 22, 23, from the condenser through the tube 25, the water flows into the pump 24, which supplies the liquid through the tube 26 to the steam generator 12. At the end of the experiment, the drives 3 and 10 are turned off, the cover 20 is opened and samples 8 and 9 are removed for research.

Figure 2, 3 and 4 shows the distribution of relative velocities, as well as collision speeds depending on the design of the ends of the tubes 15 and 16. As can be seen from the above diagrams and equations, the maximum collision speed of the sample and steam is obtained in the case of using a tube with a bent end in the direction of rotation of the accelerator bowl 21 with accelerator nozzles, for example, in the form of Laval nozzles.

V _c = V _Tr + ΔV _U.nac ,

where V _c is the collision velocity of the sample and vapor;

V _Tr - tube speed;

ΔV _us.– speed increment due to the use of accelerator nozzles, for example, Laval nozzles.

Speed diagrams (options) depending on the design of the end of the tube

1. Figure 2 presents the velocity diagram in the case of the location of the end of the tube tangentially relative to the trajectory of movement.

V _abs = V _Tr + V _pair ,

where V _abs is the absolute total speed;

V _Tr - tube speed;

V _steam - the speed of steam in a moving tube.

2. Figure 3 presents a diagram of speeds in the case when the end of the tube is bent in the direction of rotation.

V _c = V _Tr + V _pair

Figure 4 presents a diagram of speeds when an accelerator nozzle, for example, a Laval nozzle, is placed in a tube bent in the direction of rotation

V _c = V _Tr + V _pair ,

where V _c is the collision velocity of the sample and vapor;

V _Tr - the speed of the end of the tube;

V _steam is the steam velocity.

Information sources

1. Scheme of the MAI drop-percussion installation.

2. Krainev A.F. Handbook of mechanisms. - M.: Mechanical Engineering, 1981.

3. Scheme of the drop-impact machine “Erosion”.

4. Ilyin M.I. Research and development of rational forms of working surfaces of rotors of continuous inertial centrifuges. Doctoral dissertation. Krasnodar Polytechnic Institute 1975 Krasnodar.

Claims (2)

1. A test centrifugal installation, including a base, a working chamber with a cover, a lower drive with plates on the ends of which the test samples are placed, characterized in that the upper drive with an opposite (opposite) direction of rotation relative to the lower drive is placed on the cover an accelerating bowl with tubes is placed at the end of the shaft of the bearing assembly of the upper drive, and a tube is passed through the cover to supply steam to the accelerating bowl, in which the blades are parallel to the axis of rotation. 2. The test centrifugal installation according to claim 1, characterized in that the ends of the tubes are bent in the direction of rotation of the upper drive and accelerator nozzles are placed in them.

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