SU111540A1 - A device that maintains a certain level of material in a blast furnace or other furnace - Google Patents

Description

Instruments for determining the level of material in furnaces, such as gamma level gauges, are known, but they cannot be used under conditions of high temperatures and large wall thicknesses of the furnace.

The recently developed capacitance level gauges cannot also be used at high temperatures, since this results in a change in the electrical properties of materials.

The described device for maintaining a certain level of materials in the furnace is free from the indicated disadvantages. The sensor of the device is not afraid of high temperatures and can be successfully applied where it has not yet been possible to measure the level of materials using electronic automatics.

The principle of the device is as follows.

In a furnace or other container / (see Fig. 1), when it is necessary to maintain a certain level of material 2, the Za and 36 metal plates forming the first one are located, as far as possible in two mutually perpendicular planes, metal plates capacitor, and plates 4a and 46, forming the second capacitor, when connected to alternating voltage plates with a frequency of /.

These capacitors are connected to the shoulders of the bridge of the electronic unit 5 via a capacitor-type obturator or a contact-switching obturator. The obturator consists of stationary, isolated from each other metal plates Zv and 4c, the same plates b and 7 - moving, rotating from the synchronous electric motor 10, rings 8, to which the moving plates are connected, and brushes 9, removing stress from the rings.

The objective of the obturator is to alternately connect the capacitances of the sensor through the capacitances formed by the plates Sv, 4b and 6 or 7, then to one, then to the other shoulder of the bridge.

No. 111540-2 -

The unbalance voltage after amplification in an electronic unit deviates the scale pointer arrow) / right or left, depending on the unbalance phase, i.e., the magnitude of the level deviation from the O – O axis.

The secondary device 12 is used to record the level, as well as for signaling and automatic control. The level measurement method is shown in FIG. .

Below the OO level (Fig. 2, levels A to B), the scale arrow will indicate a level less than zero, and the arrow will deviate more to the left, the lower the material level.

As the zero level rises (levels C D), the unbalance voltage changes sign and the arrow will be deflected to the right.

The features of the device are as follows:

a) the scale arrow fixes only the relative change in capacitance, i.e. it shows the actual level, if the scale is scaled to the corresponding; their units;

b) the presence of only one electronic unit when measuring the material level within certain limits;

c) the ability to measure under conditions of high temperatures in the manufacture of metal plates from heat-resistant alloys;

d) the ability to automatically adjust the level within the specified limits;

e) the use of a circuit with dynamic compensation, which, by increasing the sensitivity of the device, eliminates the influence of such factors as wire capacitance, filament instability, etc .;

f) safety compared to gamma level gauges.

When using the device, it is necessary to set O correctly and fix the extreme position of the arrow on the scale when the vessel is unloaded and loaded.

With this setting, the O scale will exactly match the O – O level of the material in the vessel if the symmetry of the arrow deflections in the extreme positions is observed.

The device provides a measurement of a certain level in a blast furnace and other furnaces, which until now could not be measured due to the fact that the material during its thermal effects changes its electrical properties.

 Subject invention

The device ensures the maintenance of a certain level of material in a blast furnace or other furnace, characterized in that continuous monitoring and automation of material level control in a blast furnace or other furnace is carried out using a capacitive sensor, metal capacitor plates and an electronic unit.

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