KR100393678B1 - Detecting apparatus for slag foaming level and its method - Google Patents

Abstract

The present invention provides an apparatus and method for measuring slag forming level, the apparatus and method for measuring the forming level of slag formed in the converter using the repulsive force of the lance to inject oxygen during the blowing operation of the converter. There is this.

According to the invention, in the method of measuring the forming level of the slag 4 accommodated in the converter 3, the lance trolley 10 is inserted into the slag 4 located in the converter 3. Moving downward, blowing the oxygen at a constant pressure when the end of the lance 20 is positioned inside the slag 4, and acting in an upward direction of the lance 20 in response to the pressure of the blowing oxygen. A method of measuring slag forming level is provided, comprising: measuring a repulsive force; and calculating the forming level of the slag 4 by substituting the measured repulsive force into Equation 1 below.

Equation 1 is ΔF _lanse = A _lanse P _L = A _lanse ρs · g · ΔH.

Description

Slag foaming level measuring apparatus and its method {Detecting apparatus for slag foaming level and its method}

The present invention relates to an apparatus and a method for measuring the forming level of slag in the converter, in particular, an apparatus for measuring the slag forming level in the converter by using the repulsive force acting on the lance to inject oxygen during the blowing operation of the converter and its It is about a method.

In general, during the oxygen blowing operation of the converter, the contents of the converter, such as molten steel or slag, spring up and attach to the converter wall or slip out of the converter. Such slopeing lowers the error rate of tapping, and also results in slag composition change and heat loss, which is an unstable factor in operation.

In addition, slag and dust scattered due to the occurrence of slopes greatly shorten the life of the facility, and cause environmental pollution.

Therefore, it is very important to accurately measure the forming level of slag in the converter in order to predict the slope phenomenon in advance.

The slag forming level measurement method includes a direct measurement method and an indirect measurement method. A direct measurement method includes a method of measuring a slag forming level by sending a microwave into the converter and measuring reflected waves reflected by the slag, and an image sensor ( Image sensor). As an indirect measurement method, the horizontal vibration of the main lance at the time of oxygen injection is measured by a load cell or a vibration sensor, and the reactions in the furnace are measured to determine the correlation between the slag forming level. There is a way to get it.

Among the indirect measuring methods, the former method is described in Japanese Patent Application Laid-Open No. 56-5808, Japanese Patent Application Laid-Open No. 63-100118, and Kobe Steel Report (ISBJ, 1983, p105). The latter method is disclosed in "Japanese Patent Laid-Open No. 49-13013".

However, in the above-described method, there are various problems in accurately measuring the forming level of slag.

First, the sensor used in the method of using the microwave and the image sensor, which is a direct measurement method has a problem that it is difficult to manage and maintain in a place where a large amount of dust or high temperatures.

In addition, the method of estimating slag forming level by measuring the vibration of the main lance or the reactant in the furnace has a problem that it is difficult to accurately measure the slag forming level due to large noise or vibration generated in the surrounding environment of the converter. In addition, the method of detecting slag forming level by measuring the vibration of the lance or the reactant in the furnace is an experimental correlation and the theoretical correlation is not accurately identified.

Figure 1 is a schematic diagram showing a blow job of the converter according to the prior art, Figure 2 is a partial cross-sectional view of the slag forming level measuring device installed inside the lance bogie shown in FIG.

As shown in FIGS. 1A and 2, the slag forming level measuring apparatus using a load cell includes a lance 2 and a lance 2 inserted into the converter 3 for blowing the molten steel 5. It includes a lance trolley (1) installed at the upper end of the lance 2 to move the lance 2 up and down, and a load cell (9) installed on the side of the lance (2).

Inside the converter 3, the molten steel 5 sinks to the underside of the converter 3 by its own specific gravity, and the slag 4 floats above the molten steel 5.

The lance trolley 1 is moved downward so that the lance 2 is inserted into the converter 3, and when the end of the lance 2 is positioned inside the slag 4, oxygen is transferred through the lance 2. Eject the molten steel to start the work. At this time, the oxygen rises to the upper surface of the slag 4 in the form of bubbles, the lance 2 is vibrated by the rising bubbles, the load cell 9 provided on the side of the lance 2 is the lance 2 Measure the vibration of the.

In the vibration measuring method using the load cell 9, first, data of the degree of vibration according to the height of the slag forming level 6 are obtained by experiment. Then, the slag forming level is predicted according to the vibration degree of the lance 2 measured in comparison with the obtained data, and if the vibration becomes more severe, there is a risk of the occurrence of the slope, so the degree of vibration is reduced so that the slope does not occur. Take action to

Figure 1 (b) is a graph showing the vibration size of the lance with respect to the height of the slag forming level, according to this graph, if the height of the forming level 6 of the slag 4 is high the degree of vibration of the lance (2) You can see that it is large.

However, the vibration measuring method using the load cell 9 is not a method based on any theoretical basis, but is a method of using experimental data that the vibration increases when the height of the slag forming level 6 increases. Accordingly, the vibration measuring method using the load cell 9 causes a problem that the slag forming level 6 cannot be accurately measured in the converter 3 in which vibration and noise are severely generated.

The present invention has been made to solve the problems of the prior art as described above, and an object thereof is to provide a device and a method for measuring the slag forming level by measuring the repulsive force acting on the lance to inject oxygen.

1 is a schematic view showing a blow job of the converter according to the prior art,

FIG. 2 is a partial plan cross-sectional view of the slag forming level measuring apparatus installed in the lance trolley shown in FIG.

3 is a schematic view showing a slag forming level measuring apparatus according to a first embodiment of the present invention,

Figure 4 is a schematic diagram showing the repulsive force acting on the lance when oxygen is blown from the lance shown in Figure 3,

FIG. 5 is a plan view showing the shape and the sensor of the support shown in FIG.

6 is a front view showing a slag forming level measuring apparatus according to a second embodiment of the present invention.

♠ Explanation of symbols on the main parts of the drawing ♠

1, 10: Lance Balance 2, 20: Lance

3: converter 4: slag

5: molten steel 6: slag forming level

9, 19: load cell 29: deformation sensor

25a, 25b: support

According to the present invention for achieving the object as described above, the slag is installed around the lance and accommodated in the lance trolley, the slag for measuring the forming level of the slag by measuring the left and right vibration of the lance inserted into the converter to inject oxygen A forming level measuring apparatus, comprising: a support extending to the circumferential side of the lance; and a load cell positioned between the support and the lance bogie to measure a pressure applied to the support, wherein oxygen flows through the lance. The slag forming level measuring device is provided by measuring the repulsive force acting on the lance by blowing into the inside of the load cell and calculating the height of the forming level of the slag using the measured value.

In addition, according to the present invention, in the slag forming level measuring device is installed in the periphery of the lance is accommodated in the lance trolley, measuring the forming level of the slag by measuring the left and right vibrations of the lance inserted into the converter to inject oxygen, once The part is fixed to the circumferential side of the lance, the other end includes a support fixed to the inner side of the lance trolley, the deformation sensor is installed in the longitudinal direction of the support, the oxygen into the interior of the slag through the lance The slag forming level measuring device is provided, characterized in that the deformation sensor measures the deformation degree of the support according to the repulsive force acting on the lance and calculates the height of the forming level of the slag from the measured value.

Further, according to the present invention, in the method for measuring the forming level of the slag accommodated in the converter, the step of moving the lance bogie down to insert the lance into the slag located in the converter, the end of the lance is located inside the slag Injecting oxygen at a constant pressure, Measuring the repulsive force acting in the upper direction of the lance in response to the pressure of the oxygen to be injected, Substituting the measured repulsive force into the following equation 2 of the slag A method of measuring slag forming level is provided, comprising calculating a forming level.

In the following, with reference to the accompanying drawings, a preferred embodiment of the slag forming level measuring apparatus and method according to the present invention will be described in detail.

Example 1

3 is a schematic diagram showing a slag forming level measuring apparatus according to a first embodiment of the present invention, Figure 4 is a schematic diagram showing the repulsive force acting on the lance when oxygen is blown from the lance shown in Figure 3, 5 is a plan view showing the shape and the sensor of the support shown in Figure 3, Figure 6 is a front view showing a slag forming level measuring apparatus according to a second embodiment of the present invention.

As shown in Figures 3 and 4, the slag forming level measuring apparatus of the present invention is inserted into the converter 3, the lance 20 for blowing oxygen into the slag (4) and molten steel (5), A lance trolley 10 installed at an upper end of the lance 20 to move the lance 20 up and down, accommodated in the lance trolley 10 and extending to a side of the lance 20, and The load cell 19 is fixed to the upper surface of the support 25a and measures the repulsive force acting on the lance 20 in contact with the inner surface of the lance trolley 10.

The lance 20 is moved downward to the fixed lance trolley 10 to insert the lance 20 into the converter (3). Then, the end of the lance 20 is located inside the slag 4, and at this time, the position is fixed after the movement of the lance trolley 10 is stopped. Then, oxygen is injected into the slag 4 through a lance 20 having an end portion inside the slag 4 to perform molten steel scavenging operation.

Then, as oxygen is injected into the slag 4 through the lance 20, the repulsive force acts on the lance 20, and the repulsive force acts as a force to push the lance 20 upwards. Repulsive force for moving the lance 20 upward acts on the load cell 19 located between the support 25a and the lance trolley 10, and the load cell 19 under pressure generates an electrical signal.

On the other hand, when the height H of the forming level 6 of the slag 4 increases, the pressure for pressing the molten steel 5 increases due to the weight of the slag 4 itself, and thus the contact portion P _{L of} oxygen and the slag 4 is increased. ) Also rises. When the pressure of the oxygen and the slag (4) contact rises in this way, the repulsive force also increases, and the pressure applied to the load cell 19 also increases. Thus, it can be seen that the repulsive force is proportional to the forming level 6 of the slag 4.

In addition, as shown in (a) and (b) of FIG. 5, the lance 20 may be shaken in the left and right directions due to the generation of turbulence at the time of oxygen injection, so that the lance 20 is shaken in one load cell 19. Since the repulsive force can be measured incorrectly, the load cell 19 is installed in two or three places around the lance to measure the repulsive force acting on the lance 20.

Example 2

The slag forming level measuring apparatus according to the second embodiment of the present invention is the first embodiment except that the installation relationship between the support and the deformation sensor is installed on the support in place of the load cell of the first embodiment as compared with the first embodiment. Same as the example. Therefore, the same or similar reference numerals will be given to the same or similar reference numerals, and description thereof will be omitted here.

6 is a front view showing a slag forming level measuring apparatus according to a second embodiment of the present invention.

As shown in Figure 6, the slag forming level measuring apparatus of the present invention is inserted into the converter 3, the lance 20 for blowing oxygen into the slag 4 and the molten steel 5, and the lance 20 Installed on the upper end of the lance trolley 10 for moving the lance 20 up and down, and one end is fixed to the side of the lance 20 and the other end is fixed to the inner side of the lance trolley 10 (b) And a deformation sensor 29 installed on the support 25b to measure the deformation of the support 25b.

On the other hand, when oxygen is injected into the slag 4 through the lance 20, the repulsive force acts in the upper direction of the lance 20 to deform the support 25b fixed to both ends of the lance 20. At this time, the deformation of the support 25b is measured by the deformation sensor 29 installed in the support 25b. If the repulsive force is large, the deformation of the support 25b is also large. Therefore, the forming level 6 of the slag 4 can be predicted by the deformation amount of the support 25b measured by the deformation sensor 29.

In addition, since the lance 20 can be shaken in the left and right direction, the deformation sensor 29 is installed at two or three places around the lance to measure the repulsive force applied to the lance 20.

The slag forming level measuring method configured as described above will be described in detail.

When the end of the lance 20 is positioned inside the slag 4 and oxygen is blown in, the slag 4 is foamed and the height H of the slag 4 is increased. Then, the pressure increases due to the weight of the slag 4, the pressure P _L of the contact portion of the oxygen and the slag 4 also rises, and the repulsive force F acting on the lance 20 also increases.

Therefore, the repulsive force acting on the lance 20 and the height of the slag forming level 6 are proportional to each other and the repulsive force to be pushed to the upper portion of the lance 20 is measured, and the correlation coefficient is obtained, the height of the forming level 6 of the slag 4 is obtained. Can be obtained.

Ps = Msg / As = ρsgH

P _L = Ps = ρsg

F _lanse = A _{lanseP L} = A _lanse

Where P _L is the pressure of the slag at the site where the rate of oxygen blown through the lance becomes zero (Zero), Ps is the pressure of the slag in the same horizontal plane as P _L , ρs is the mass of the slag, g Is the acceleration of gravity, H is the height from the part of P _L to the slag forming level, As is the surface area of the slag forming level, F _lanse is the repulsive force, and A _lanse is the area of the inlet of the lance.

ΔF _lanse = A _{lanseP L} = A _lanse

Here, ΔF _lanse is the amount of change in the repulsive force, and ΔH is the amount of change in the height of the forming level of the slag.

As described in detail above, the slag forming level measuring apparatus and the method of the present invention can improve the reliability of slag forming level measurement because it is hardly affected by the vibration and noise of the converter, and uses a sensor vulnerable to heat or dust. This can reduce the number of maintenance or repairs.

Although the technical idea of the slag forming level measuring apparatus and the method of the present invention has been described above with the accompanying drawings, this is illustrative of the best embodiment of the present invention by way of example and not by way of limitation. In addition, it is obvious that any person skilled in the art can make various modifications and imitations without departing from the scope of the technical idea of the present invention.

Claims (3)

In the slag forming level measuring device is installed around the lance and accommodated in the lance trolley, and measuring the forming level of the slag by measuring the left and right vibration of the lance inserted into the converter to blow oxygen, A support extending to the circumferential side of the lance; A load cell positioned between the support and the lance bogie to measure the pressure applied to the support; Slag forming level measuring apparatus characterized in that the oxygen is blown into the interior of the slag through the lance to measure the repulsive force acting on the lance with the load cell and calculate the height of the forming level of the slag from the measured value. In the slag forming level measuring device is installed around the lance and accommodated in the lance trolley, and measuring the forming level of the slag by measuring the left and right vibration of the lance inserted into the converter to blow oxygen, One end is fixed to the circumferential side of the lance, and the other end is a support fixed to the inner side of the lance bogie; It includes a deformation sensor installed in the longitudinal direction of the support, When the oxygen is blown into the slag through the lance, the deformation sensor measures the deformation degree of the support according to the repulsive force acting on the lance and calculates the height of the forming level of the slag from the measured value. Slag forming level measuring device. In the method for measuring the forming level of the slag accommodated in the converter, Moving the lance bogie down to insert the lance into the slag located within the converter; Injecting oxygen at a constant pressure when the end of the lance is positioned inside the slag, Measuring the repulsive force acting in an upward direction of the lance in response to the pressure of the blown oxygen, And calculating the forming level of slag by substituting the measured repulsive force into Equation 1 below. Equation 1 ΔF _lanse = A _{lanseP L} = A _lanse Where ΔF _lanse is the change in repulsive force, ΔH is the change in the height of the slag's forming level, P _L is the pressure of the slag at the site where the rate of oxygen blown through the lance is zero, and ρs The mass of the slag, g is the acceleration of gravity, and A _lanse is the area of the inlet of the lance through which oxygen is blown.