RU2526597C1 - Bench for nozzle testing - Google Patents

Abstract

FIELD: testing equipment.

SUBSTANCE: device comprises two vertical guides, upper ends of which are stiffly connected with a crosspiece, a horizontal frame placed between two vertical guides as capable of movement in the vertical direction and made in the form of two knee pieces, the vertical shelves of which are located in vertical guides, and a cross beam is fixed on horizontal shelves, three units for nozzle fixation, a high pressure pump, a hoist with a rope, where the horizontal frame is suspended, a block for the hoist rope fixed in the central part of the specified crosspiece, a recorder, a model fire seat. One of units for nozzle fixation is fixed on the cross beam, and two others are fixed on vertical shelves, which have height much higher than the critical value that corresponds to jamming of the frame during its movement and determined in accordance with the formula.

EFFECT: expanded arsenal of technical facilities for nozzle testing.

6 cl, 2 dwg

Description

The invention relates to testing equipment, and in particular to stands for testing nozzles designed to spray a fire extinguishing agent during a fire extinguishing.

No prior art analogues have been identified.

The present invention solves the problem of creating a simple and reliable bench for testing nozzles.

The technical result consists in expanding the arsenal of technical means for testing nozzles.

The specified technical result is achieved due to the fact that the test bench for nozzles includes two vertical guides, the upper ends of which are rigidly connected by a crossbar, a horizontal frame placed between two vertical guides with the possibility of movement in the vertical direction and made in the form of two squares, the vertical shelves of which are located in vertical guides, and on horizontal shelves, a transverse beam is fixed, three nodes for attaching the nozzle, high pressure pump, winch with a cable on which a horizontal frame is suspended, a winch cable unit fixed in the central part of the crossbar, a registrar, a model fire center, one of the nozzle attachment assemblies is fixed on the transverse beam, and the other two are mounted on vertical shelves that have height (h) is much greater than the critical value (hcr.), corresponding to jamming of the horizontal frame during its movement and determined by the formula

h cr. = e · 2f,

where e is the displacement of the center of mass of the horizontal frame from its axis of symmetry;

f is the coefficient of friction.

The proposed stand for testing nozzles is illustrated by the drawings shown in Fig.1,2.

Figure 1 shows a front view of the stand installed in the room.

Figure 2 - diagram of the application of forces in the case of a displacement of the center of mass of the horizontal frame from its axis of symmetry.

The injector test bench contains two vertical guides 1 (Fig. 1), the upper ends of which are rigidly connected by a crossbeam 2, a horizontal frame 3 placed between two vertical guides 1 with the possibility of movement in the vertical direction, the winch 4 with a cable 5, on which a horizontal frame 3, block 6 for winch cable 4, mounted in the central part of the crossbeam 2, high pressure pump (not shown in the drawing), including a drive and pressure gauge, recorder (not shown in the drawing), made in the form of a camera or a video camera and intended for shooting the process of extinguishing a fire, three nodes 7 for attaching a nozzle, a model fire center 8. The lower ends of the vertical rails 1 are fixed to the foundation (not shown in the drawing). Suspension by a cable 5 of a horizontal frame 3 is carried out along its axis of symmetry.

The horizontal frame 3 consists of two squares 9 and a transverse beam fixed to the horizontal shelves of the squares 9, and the vertical shelves of the latter are located in the vertical guides 1, which are made, for example, of a channel. The vertical and horizontal shelves of each square 9 are connected by a jib 10.

On the transverse beam of the horizontal frame 3 in its middle part one of the nozzle attachment units 7 is fixed, and the other two are fixed on the vertical shelves of the squares. The vertical shelves of the squares 9 have a height (h) (Fig. 2) much greater than the critical value (hcr.), Corresponding to the jamming of the horizontal frame 4 when moving it.

The high-pressure pump is designed to supply a fire extinguishing agent, for example, water or a mixture of water with a foaming agent in a predetermined proportion and is connected by a high-pressure sleeve (not shown in the drawing) to the nozzle.

Model fire center 8 is made in the form of a baking sheet with a combustible mixture, for example a mixture of water and gasoline in a certain proportion, and is located between two vertical rails 1 on the floor or on the ground. The size of the pan and the amount of the combustible mixture depends on the rank of the model fire center 8 of the fire.

The nozzle attachment unit 7 is configured to change its position.

To determine the critical value (hcr.) Of the height of the vertical shelves of the squares 9, we assume that the center of mass of the horizontal frame 3 is offset from its axis of symmetry passing through point C by an amount e (figure 2). When the frame 3 is skewed at points A and B, reactions N are normal to the vertical guides 1, which create friction forces F directed against the force of weight P. Due to the actual smallness of the gaps between the vertical shelves of the squares 9 and the vertical guides 1, in comparison with the dimensions frame 3, the angle α of inclination of the frame 3 is neglected (the angle is indicated for clarity of the loading pattern).

Assuming that e << L, we write down the projections of the forces on the coordinate axis and the moment relative to point B.

(x) N-N = 0

(y) P-2F-0 or $$F=P/2(\mathrm{one})$$

$$(\cdot )\text{B p}\cdot \text{bN}\cdot \text{hF}\cdot \text{L}=\text{0}\text{, (2)}$$

where b = L / 2 + e

For the friction force F, we have

F = N · f, whence $$N=F/f,(3)$$

where f is the coefficient of friction.

Substituting expressions (1) and (3) into expression (2), we obtain

b-h / 2f-L / 2 = 0

or

$$(L/2+e)-h/2f-L/2=0(\mathrm{four})$$

Expression (4) gives the aspect ratio in which, according to condition (1), the horizontal frame will jam in the vertical guides 1.

In particular, from expression (4) we obtain the critical value of the height (hcr.) Of the vertical shelves of the squares

$$h\mathrm{to}R.=e\cdot 2f(5)$$

Therefore, to prevent jamming of the horizontal frame 3 in the vertical guides, the height (h) of the vertical shelves of the squares 9 should be much greater than the critical value (hcr.).

Using the inventive stand allows the following:

- change the distance between the nozzle and the model fire during the test;

- experimentally determine the distance from the nozzle to the model fire site, on which the nozzle acts effectively;

- empirically determine the number of nozzles needed to eliminate the fire, depending on its volume;

- determine the dependence of the efficiency of the nozzle on changes in its design parameters;

- to develop recommendations for extinguishing fires of different classes using nozzles of various designs.

In addition, the simplicity of the design of the inventive stand provides quick installation and dismantling, as well as reliability and ease of use.

Stand for testing nozzles works as follows.

Tests are carried out in accordance with the test program. A horizontal frame 3 is installed at a predetermined distance from the model fire center 8, the nozzles are connected by high pressure hoses to a high pressure pump. They ignite the combustible mixture in a baking sheet and withstand a free burning time of 60 s, turn on the drive of the high-pressure pump, which delivers water, for example, from a container under a given pressure through nozzles to model fire center 8, and measure the parameters in accordance with the test program, as well as shooting the process of extinguishing a model fire.

In the prior art, no tool has been identified that is inherent in all the features set forth in the formula, which indicates the compliance of the claimed technical solution with the criterion of "novelty."

In the prior art, no solutions have been identified that have features that match the features of the claimed technical, which indicates the conformity of the claimed technical solution to the criterion of "inventive step".

Claims (6)

1. The test bench for nozzles, characterized in that it includes two vertical guides, the upper ends of which are rigidly connected by a crossbar, a horizontal frame placed between two vertical guides with the possibility of movement in the vertical direction and made in the form of two squares, the vertical shelves of which are located in vertical guides, and on horizontal shelves a transverse beam is fixed, three nodes for attaching the nozzle, a high pressure pump, a winch with a cable on which is suspended a horizontal frame, a winch cable block fixed in the central part of the said crossbeam, a recorder, a model fire center, one of the nozzle attachment assemblies is fixed on the transverse beam, and the other two are mounted on vertical shelves that have a height (h) of many more than the critical value (hcr.), corresponding to jamming of the horizontal frame during its movement and determined by the formula
hcr. = e · 2f,
where e is the displacement of the center of mass of the horizontal frame from its axis of symmetry;
f is the coefficient of friction. 2. The stand according to claim 1, characterized in that the recorder is made in the form of a camera or camcorder. 3. The stand according to claim 1, characterized in that the model fire is made in the form of a baking sheet with a combustible mixture. 4. The stand according to claim 1, characterized in that the high-pressure pump is designed to supply an extinguishing agent, such as water or a mixture of water and a foaming agent. 5. The stand according to claim 1, characterized in that the vertical and horizontal shelves of each square are connected by a jib. 6. The stand according to claim 1, characterized in that the high pressure pump is connected to the nozzles by high pressure hoses.

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