RU2513879C1 - Bench to select thickness of fence designed for protection against fragments of explosive nature - Google Patents

Abstract

FIELD: blasting.

SUBSTANCE: bench for selection of thickness of a fence designed for protection against fragments of explosive nature comprises an explosive chamber, in the upper base of which there is a hole covered with an element, the area of the hole may vary by screwing replaceable rings, the element closes the hole in the ring, above which the fence is fixed. The second hole is closed with a valve, which is pressed to the hole with the help of the electromagnet and is opened by a spring as contacts open. The force of pressing the valve and compression of the spring is set so that the total force is equal to the permissible pressure multiplied by the area of the valve opening. The closing element is made as imitating a fragment of an explosive nature, above which a model protective fence is installed. The surface of the closing element facing the model protective fence comprises a surface that models irregularities inherent to fragments of the explosive nature.

EFFECT: increased efficiency of fence protection.

1 dwg

Description

The invention relates to safety systems in emergency situations and can be used to select the thickness of the fence, designed to protect against fragments of the explosive nature of technological equipment.

The closest technical solution to the claimed object is a stand according to the patent of the Russian Federation No. 2459050 (prototype), containing an explosive chamber, in the upper base of which there is a hole overlapped by an easy-to-reset element, the area of the hole can be changed by screwing interchangeable rings, and the discharge element overlaps the hole in the ring, over which a protective shield is fixed, and the second hole is blocked by a valve, which is pressed against the hole by an electromagnet and opens by a spring when the contact opens s, and the pressing force of the compression spring and the valve is set so that the total force equal admissible pressure multiplied by the valve opening area.

A disadvantage of the known solution is the lack of the possibility of comparative tests of the fence, designed to protect against fragments of the explosive nature of technological equipment at model sites.

The technical result is an increase in the effectiveness of the protection of the fence, designed to protect against fragments of the explosive nature of technological equipment in emergency mode at the facility.

This is achieved by the fact that in the stand for selecting the thickness of the fence, designed to protect from explosive fragments, containing an explosive chamber, in the upper base of which there is a hole covered by an element, the hole area can be changed by screwing interchangeable rings, and the element overlaps the hole in the ring, over which the fence is fixed, and the second hole is blocked by a valve, which is pressed to the hole with an electromagnet and opens with a spring when the contacts open, and the force at Atia valve and a compression spring is installed so that the total force equal allowed by the pressure multiplied by the valve opening area, i.e. ΔF = Fe.m -Fpr = ΔRd.m Scl,

where Fe.m - the force of the electromagnet, pressing the valve to the hole, N / m ² ; Fpr - spring compression force opening the valve, H: Fpr = (10 ÷ 15) gm, where g = 9.81 m / s ² ; m is the mass of the core of the electromagnet with the valve, kg; ΔP _D.M. - differential pressure for model installation; Scl is the area of the valve opening, m ² , the element is imitating an explosive fragment, over which a model protective fence is installed, and the surface of the element facing the model protective fence has a surface simulating irregularities inherent in explosive fragments.

The drawing shows a diagram of the stand.

The stand for selecting the thickness of the fence, designed to protect against fragments of an explosive nature, consists of an explosive chamber 1, which is a metal vessel with a volume equal to 5004-1000 cm ³ (wall thickness 7-8 mm). In the upper base of the vessel there is a hole overlapped by an element 2 imitating an explosive fragment, and the surface of the element 2 facing the model protective fence 3 may have a surface simulating irregularities inherent in explosive fragments (not shown).

The area of the hole can be changed by screwing the interchangeable rings 21. The element 2, imitating an explosive fragment, overlaps the hole in the ring 21, over which the tested model protective fence 3 is fixed.

The second hole is closed by a valve 19, which is pressed against the hole by an electromagnet 12 and opens by a spring 11 when the contacts 4 are opened. The force of pressing the valve and compression of the spring is set so that the total force is equal to the allowable pressure multiplied by the area of the valve opening, i.e. .

$$\Delta F=F\mathrm{uh}.m-FPR=\Delta Rd.mS\mathrm{to}l,\left(\mathrm{one}\right)$$

where Fe.m - the force of the electromagnet, pressing the valve to the hole, N / m ² ; Fpr - spring compression force opening the valve, H: Fpr = (10 ÷ 15) gm , where g = 9.81 m / s ² ; m is the mass of the core of the electromagnet with the valve, kg; Scl - the area of the valve opening, m ² .

The pulling force of the electromagnet can be changed by changing the current through the rheostat 8 through the movable contact 9 of the rheostat. To measure the force of the electromagnet and the compression of the spring, a parallel device of the electromagnetic valve 6 is provided, the magnitude of the electromagnet current in which is regulated from the same rheostat 8 by switching contacts 5. For setting the required difference in the efforts of the electromagnet and the spring, there is a dynamometer 7. For the formation of a vapor-explosive mixture in the chamber vaporizer plug 18, into which the required amount of flammable liquid is introduced using a burette, and the plug is screwed so that the liquid vapor is black Without a window in the walls of the tube-evaporator fall into the chamber and, mixed with air, form an explosive mixture.

The mixture is ignited by an electric spark 20 from the induction coil 14, the ignition is turned on by the button 13. In one of the end (side) walls of the explosive chamber 1 there is an opening for the fitting 17, in which the tube from the blower 15 is blocked by a valve 16. In another, opposite, the end (side) wall of the explosive chamber 1 has an opening for a fitting 23 for the tube 22, which is blocked by a valve 24, which serves to maintain atmospheric pressure in the chamber 1 during liquid evaporation.

Stand for the selection of the thickness of the fence, designed to protect against fragments of an explosive nature, works as follows.

The area of the hole can be changed by screwing the interchangeable rings 21. The element 2, imitating an explosive fragment, overlaps the hole in the ring 21, over which the tested model protective fence 3 is fixed.

The first test is carried out with the lightest element 2. If the model protective fence 3 is not broken, then either increase the explosion force in the explosive chamber 1, or increase the mass of the element 2 imitating an explosive fragment, and so on until the fence 3 is pierced. At the same time, all test parameters are fixed for which a breakdown of the fence of a given thickness occurred. Thus, the minimum possible thickness of the model protective fence 3 is selected taking into account the characteristics of the explosive effect.

Claims (1)

A stand for selecting the thickness of the fence designed to protect against explosive fragments, containing an explosive chamber, in the upper base of which there is a hole overlapped by the element, the hole area can be changed by screwing interchangeable rings, and the element overlaps the hole in the ring over which the fence is fixed, and the second hole is blocked by a valve, which is pressed against the hole by an electromagnet and opens by a spring when the contacts open, and the force of pressing the valve and compression spring us is set so that the total force equal allowed by the pressure multiplied by the valve opening area, i.e. ΔF = Fe.m-Fpr = ΔRd.m Scl,
where Fe.m is the force of the electromagnet pressing the valve to the hole, N / m²;
Fpr - spring compression force, opening valve, H;
Fpr = (10 ÷ 15) gm,
Where g = 9.81 m / s²;
m is the mass of the core of the electromagnet with the valve, kg;
ΔP_D.M. - differential pressure for model installation;
Scl - valve opening area, m²,
characterized in that the element is made imitating a fragment of an explosive nature, over which a model protective fence is installed, and the surface of the element facing the model protective fence has a surface simulating irregularities inherent in fragments of an explosive nature.