RU16956U1 - DEVICE FOR DETERMINING THE CONCENTRATION LIMITS OF FLAME DISTRIBUTION - Google Patents

Abstract

A device for determining the concentration limits of flame propagation, comprising a heating cabinet with an electric heater, a reaction vessel, a vacuum pump, to which a reaction vessel, a vacuum gauge, a steam or gas supply unit, and ignition electrodes are attached to the bottom of the reaction vessel, which is characterized in that the reaction vessel has rigidly fixed upper and lower covers; it is additionally equipped with a fan for mixing the reaction mass and sensors for recording a temperature jump.

Description

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DEVICE FOR DETERMINING CONCENTRATION FLAME DISTRIBUTION LIMITS

The utility model relates to the field of determining the fire and explosion hazard of substances and materials, namely, to determining the concentration limits of flame propagation in gas and vapor-air mixtures, and can be used to categorize explosive and fire hazard industries, when calculating explosion-proof concentrations of gases and vapors inside technological systems, as well as when calculating the maximum permissible explosion-safe concentrations in the air of the working area with potential ignition sources, be used as an outcome s materials (data) for the design of new and reconstruction of old plants.

A known design of the installation GOST 12.1.044-84, consisting of a reaction vessel, pipelines with valves, an evaporator, a vacuum pump and an end switch. The reaction vessel has ignition electrodes, a convective stirrer, a flame arrester, a temperature sensor, a purge hole, a viewing window in the upper cover, a control mechanism for the lower cover, gas inlets and outlets.

The disadvantages of the known design are: the lack of temperature control of the reaction vessel and pipelines;

- the movable bottom cover of the reaction vessel, which does not allow ignition at a pressure other than atmospheric.

The known design of the installation GOST 12.1.044-89, selected as a prototype, having a heating cabinet with ventilation, inside which there is a reaction vessel with pipelines, ignition electrodes in the lower part, a flame arrester, a movable lower cover, a viewing window along the entire height of the reaction vessel and two convective stirrer.

The disadvantages of the known design are:

-Moving bottom cover of the reaction vessel;

-low value of extensible pressure limits from 100 Pa to 200 kPa for the reaction vessel and pipelines;

- the inability to determine the normal speed of flame propagation;

IPC G 01 N25 / 54

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The proposed device solves the problem of determining the concentration limits of flame propagation at pressures from O to 0.3 MPa and determining the normal flame propagation velocity.

The figure 1 presents the proposed device.

A device for determining the concentration limits of flame propagation contains a sealed reaction vessel 1, which is a copper cylinder with a height of 530 mm and an inner diameter of 80 mm with a viewing window 2 along the entire height of the vessel. The vessel is closed from above by a lid 3, on which a 4-day fan is installed; stirring the reaction mixture and a vacuum gauge 5. The vessel has a rigidly fixed lower cover 6 and ignition electrodes 7 installed inside the vessel in its first part and connected by wires to the ignition device 8. The reaction vessel communicated by pipelines 9, 10, respectively, with a vacuum pump 11 and an evaporator 12, and also has an air duct 13 connected to the volume of the heating cabinet 14. On the walls of the reaction vessel are sensors for detecting a temperature jump 15, 16, signal to the registration unit 18. The reaction vessel is located in a heating cabinet 14, equipped with a heater 17.

The installation is as follows.

Check the health of the ignition device 8 by closing the circuit and applying a spark to the ends of the electrodes 7.

The reaction vessel 1 vaccines die to a residual pressure of 1-2 mm Hg using a vacuum pump 11 and check the vessel for leaks. Monitoring the increase in pressure is carried out using a vacuum gauge 5. The reaction vessel is considered airtight and suitable for work if the increase in pressure due to leaks does not exceed 1 mmHg. in 30 minutes. Then, hot steam from the evaporator 12 is supplied to the reaction vessel in the calculated volume. Then through the duct 13 serves air (oxidizing agent). The amount of fuel component and air supplied is controlled by a vacuum gauge 5. The mixture components are mixed in the reaction vessel with a fan 4 for 0.2 minutes, then the fan 4 is turned off, the vacuum gauge 5 is crushed and the mixture is ignited using an igniter 8 and electrodes 7. Observation the flame is carried out visually through the viewing window 2. The flame propagation speed is measured by temperature jump detection sensors 15.16.

This is achieved by the fact that the device for determining the concentration limits of flame propagation, containing a heating cabinet with an electric heater, a reaction vessel, a vacuum pump, to which a reaction vessel, a vacuum gauge, a steam or gas supply unit and ignition electrodes are attached, mounted in the lower part of the reaction vessel, is additionally equipped with a fan, for mixing the reaction mixture, temperature jump detection sensors. The reaction vessel has a rigidly fixed upper and lower covers.

The hermetically sealed reaction vessel allows it to withstand pressure from 0 to 0.4 MPa, i.e. determine the concentration limits of flame propagation in the range from 500PadO.ZMPa.

The presence of a fan in the reaction vessel allows the mixing of heavier reaction masses.

Temperature jump detection sensors allow you to determine the normal speed of flame propagation through the reaction volume.

Claims (1)

A device for determining the concentration limits of flame propagation, containing a heating cabinet with an electric heater, a reaction vessel, a vacuum pump, to which a reaction vessel, a vacuum gauge, a steam or gas supply unit, and ignition electrodes are attached to the bottom of the reaction vessel, characterized in that the reaction vessel has rigidly fixed upper and lower covers; it is additionally equipped with a fan for mixing the reaction mass and sensors for recording a temperature jump.