KR20060022919A - Sampling device for complex probe for obtaining the sample with high purity - Google Patents

Abstract

The present invention relates to an improved sampling probe for composite probes capable of collecting a single sample of a sample for analyzing the temperature, oxygen and components of molten metal in a steelmaking process.

The present invention is a composite probe sampling port consisting of a chamber mold having a molten metal flow inlet and a molten metal flowing through the molten steel sample and the molten steel sample is solidified through the water flow in the molten metal, the filter in the loss mold Provides a sample collection port for a composite probe characterized in that the insertion is formed.

In another aspect, the present invention provides a sample collection port for a composite probe characterized in that the gas outlet is installed on the bottom of the sampling port or the loss mold is formed in a volume of 5 ~ 11% of the volume of the water bath.

According to the present invention, a large amount of slag is generated by the input of ferroalloy and subsidiary materials according to the operation of refining, and the sound sample is continuously changed due to the severe fluctuation of the molten surface by injecting inert gas from the side of the bottom of the furnace to improve the efficiency of the refining reaction. It is not necessary to carry out temperature measurement and sampling operation by operating the furnace to obtain the component information in the element process known to be impossible to collect.Increase the efficiency of refining work by shortening the refining time by quickly obtaining process information. And manual harvesting increases worker safety and labor productivity.

Composite probe, sampler, filter

Description

Sampling device for Complex Probe for obtaining the sample with high purity

1 is a structural diagram of a composite probe equipped with a conventional sampling port,

2 is a structural diagram of a conventional sampling port,

Figure 3 is a cross-sectional view of the sampling port of an embodiment of the present invention,

4 is a cross-sectional perspective view of a sampling port of an embodiment of the present invention;

5 is a perspective view of the lower part of the loss of one embodiment of the present invention;

6 is a cross-sectional view of a sampling port of an embodiment of the present invention,

Figure 7 is a state diagram of a sample prepared using the sampling port of the present invention.

Explanation of symbols on the main parts of the drawings

10: Lost mold 11: Tanggu 12: Tangdo

13 filter 14 gas outlet 17 loss

18: You 20: You

The present invention relates to an improved sampling port mounted on a composite probe capable of detecting temperature, oxygen and composition information of molten metal in a steelmaking process.

In general, during the steelmaking process of steel mills, probes are used to measure components, temperatures, and the like in molten steel, and probes having various functions are called composite probes.

1 shows a structural diagram of a composite probe equipped with a conventional sampling port.

The composite probe 1 is fixed by inserting the temperature measuring element 3 at the lower end of the main branch pipe 2, and the sampling port 4 is placed inside the main branch pipe 2 adjacent to the upper side of the temperature measuring element 3. It consists of a structure that is equipped with immersion in the molten metal in various refining furnaces (electric converter, electric furnace, AOD, VOD, RH-OB, LF, LT, B / B, etc.) during the steelmaking process to collect the sample and Will be measured.

However, especially in the reduction desulfurization step of the stainless refining furnace, the metal oxide produced during the decarburization process of the refining is reduced, and the sulfur contained in the molten metal reacts with CaO added as an auxiliary material and is removed into the slag.

At this time, a large amount of slag is generated by deoxidation by silicon (Si), high basic air conduction of slag, improvement of slag recycling rate, vigorous stirring, and the addition of ferroalloy and secondary raw materials according to the reduction and desulfurization treatment step. Since the side surface is blown into the molten metal, the fluctuation of the hot water surface is severe, and accordingly, the interface between the slag and the molten metal is not clearly distinguished, so that a healthy sample cannot be collected by the conventional probe.

2 is a detailed view of a conventional sampling port 4, (a) is a cross-sectional view, (b) is a cut perspective view.

The ordinary sampling port 4 is composed of a loss chamber 5 and a basement 6, and molten steel enters the loss chamber 5 from the mouth 7 and descends to the basement 6 through the water supply 8 to solidify. It becomes a sample for component analysis.

In the case of using a probe equipped with the above-mentioned sampling port by using an automatic device, a large amount of slag generated during the refining process of molten metal is mixed into the sample for analysis, causing component variation and causing defects in the sample. Component analysis becomes impossible.

In addition, a large amount of gas contained in the molten metal causes voids, bubbles, etc. in the analytical sample, thereby making it impossible to analyze the components. In particular, in the case of stainless steel, since the thermal conductivity is only 1/5 of that of general steel, when the probe is in the molten metal, solidification in the basement (6) is not completed, and thus the gas existing in the center cannot be discharged to the outside. The probe is drawn out of the molten metal. At this time, the narrow water bath (8), which is only about 2% of the volume of the basement (6), is solidified first, and solidifies with a gas trapped inside the sample, so that a large cavity is generated in the sample for analysis. there was.

Due to this problem, in the practical industry, the probe cannot be used, and the operator can measure the temperature directly by using a spoon and perform a sampling operation using a spoon or the like.

However, by such manual work, refining time is increased, thereby causing problems such as deterioration of productivity, increase of refractory loss, temperature drop, safety of operators, and the like. As a result, tapping is delayed, and the tapping target temperature is increased to 10 ° C in consideration of the temperature drop due to furnace tilt, thereby greatly reducing the efficiency of the process and the productivity of the refining furnace.

In addition, there is a problem that a worker must approach a refining furnace of high temperature for temperature measurement and sampling work, and there are safety risks due to scattering of molten metal. there was.

The present invention was devised to solve this problem in view of the above-described problems of the prior art, and uses a filter inside the chamber to prevent slag of a small amount of slag flowing into the chamber. Its purpose is to secure a healthy sample by adsorbing and changing the inevitable turbulent flow to laminar flow by iron positive pressure so that it can be sequentially charged and flow into the cellar.

  In addition, the present invention is to control the size of the molten metal and to install a gas outlet to minimize the inflow of the gas contained in the molten metal, to prevent the solidification of the molten metal first, and to control the temperature of the molten metal flowing into the basement low The purpose is to secure a healthy sample by reducing the superheat of molten steel.

In addition, the present invention is to maximize the heat capacity of the chamber in order to increase the solidification rate of the molten steel flowed into the basement and to optimize the shape of the sample to be collected, without having to remove the coagulation residue of the loss immediately transferred to the sample carrier to the analysis chamber The purpose of the present invention is to enable automatic temperature measurement and sampling in the refining process without furnace tilt, thus improving productivity in the refining process and ensuring safety of work.

In order to achieve the above technical problem, the present invention communicates with the inside of the loss mold through a loss mold having a molten metal into which a molten metal is introduced, and the sample collection port for a composite probe made of a hollow mold in which a molten steel sample is solidified. In the present invention, there is provided a sample collection port for a composite probe, characterized in that the filter is inserted into the loss mold.

In addition, the present invention is in the sample collection port for a composite probe made of a loss mold which is in communication with the interior of the loss mold and the molten steel sample is solidified through the loss mold and the melt flow in which the molten metal is introduced, Provides a sample probe for the composite probe, characterized in that the volume formed of 5 ~ 11% of the volume of the basement.

In addition, the present invention in the sample collection port for a composite probe made of a loss mold and the molten steel sample is in communication with the interior of the loss mold through the melt flow through the molten metal flowing in the molten metal, the loss mold Provides a sample collection port for the composite probe, characterized in that the gas outlet is installed on the bottom of the.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

Figure 3 is a cross-sectional view of an embodiment of a sampling port equipped with a filter in the chamber (a) is a case of a cylindrical cylinder, (b) is a case of a hexahedral filter.

The sampling port inserted into the main branch pipe of the probe has a spout 11 formed on one side thereof, and has a loss mold 10 having a cylindrical or partial hexahedron shape and a lower portion of the loss mold 10. 12) is communicated with the loss mold 10 and separated into a base mold 20 in which the molten metal to be collected is filled, and the space formed by the loss mold 10 is formed by the loss 17 and the base mold 20. This is called the base (18). Furthermore, the loss mold 10 may be divided into an upper loss mold 15 and a lower loss mold 16.

A cylindrical or hexahedral filter 13 is mounted inside the loss mold 10, particularly inside the lower loss mold 16.

The loss mold 10 is divided into an upper portion and a lower portion or left and right sides, and the upper loss mold 10 has a cylindrical shape around the center of the mouth to facilitate the inflow and flow of the molten metal. In addition, the cylindrical shape facilitates the insertion of the deoxidizing material wound in the spring shape and improves the deoxidation efficiency. In this case, as the deoxidizer, Ti, Zr, Al, or the like may be used.

The lower loss mold 16 maximizes the surface area of the filter 13 to which the inside is formed and mounted in a cylindrical shape to improve the trapping capacity and the gas discharge capacity of the slag and lower the molten steel superheat.

In addition, the lower loss mold 16 may be formed into a hexahedron shape, so that the hexahedral filter 13 is inserted into the lower loss mold 16, so that the upper loss mold 15 has a cylindrical shape. As a result, the filter 13 is supported and fixed, thereby facilitating a manufacturing method and improving the assemblability of the filter 13.

  The inside of the base mold 20, that is, the base 18 is formed so that the inner diameter decreases at a constant ratio from the top to the bottom, thereby inducing directional coagulation of the sample to be collected and moving the defect portion of the sample upward, thereby making the sample analysis site sound. Can be secured.

In addition, the heat capacity of the base mold 20 is changed according to the specific heat of the mold material and the weight of the mold, and in order to maximize the heat capacity of the base mold 20, the size of the sample is reduced and the base mold ( 20) Increasing the thickness d of the lower surface and maximizing the thickness of the side surface, increasing the cooling rate of the molten steel introduced from the upper chamber 17, shortening the solidification time and inevitably completing the solidification when the probe is in the molten metal. The resulting solidification defect can be moved from the analysis surface toward the loss 17 to ensure sufficient integrity of the analysis surface of the sample.

At this time, the heat capacity is preferably 50cal / ° C. or more, the size of the sample is 45 ~ 55mm, the thickness (d) of the base mold 20 is 15 ~ 25mm.

The loss mold 10 is preferably made of ceramic (Al2O3-SiO2) instead of silica sand (SiO2). The ceramic powder is manufactured by compression molding after compression molding using a compression molding machine and then sintered to expose to hot molten steel. Ensure the heat resistance of the sampling port. This is because it is possible to prevent the pick-up of carbon components due to contamination, and the material forming the base mold 20 is preferably made of cast iron and cast steel having a large specific heat, easy processing, and low cost to ensure the integrity of the sample.

The protrusion height in the loss of the filter 13 is preferably maintained at the radius of the tap 11, that is, the height of the center line of the tap 11, which is higher than the center line of the tap 11. When it is low, when the sample is to be separated from the probe, molten steel flows and solidifies on the upper surface of the filter and the inlet side of the tap, and thus, molten steel that is larger than the outer diameter of the sample is formed on the tap 11, so that pretreatment of the sample is required or hammered. Tapping operation should be performed, and if it protrudes too high than the center line of the tapping hole 11, since the sample of the chamber is not filled due to the inflow of molten steel, it is preferable to be formed at -5mm to + 5mm at the center line of the tapping hole 11. Do.

At this time, the outer width of the filter should be smaller than the outer diameter of the sample. The reason for this is that, as described above, when the protrusion height of the filter 13 is lower than the center line of the tap, the molten steel may flow down at the inlet side of the tap, so that unnecessary molten steel may solidify on the outside of the filter. To give as much room as possible.

In general, the carrier used to send the sample to the analysis chamber in the field is about 85 mm in length, so the total length of the sample and the loss forming part is 80 mm. Therefore, when the sample size is 50 mm, the thickness of the filter 13 is within 30 mm. Is appropriate.

The material of the filter 13 is zirconia-based in a high temperature environment of 1600 ° C or higher, alumina-based at 1,500-1,600 ° C, and silica-based at 1,300-1,500 ° C for high temperature characteristics and precise component control.

The different materials for each temperature range are used to prevent the loss of the function of the filter used in the sampling port in the range in which the intrinsic properties of the material do not change at each temperature. When a silica-based filter is used in a high temperature environment of 1600 ° C or higher, phase transformation starts to occur around 1350 ° C and melts in the vicinity of 1600 ° C. Thus, porous pores are blocked and the filter is melted, and the melt of the filter is mixed in the room. This is because it adversely affects soundness.

The filter maintains porosity by using porous ceramics made of a disordered sponge shape in which the molten metal has a path of movement through the pores in a porous form rather than one direction.

The pores of the filter use a filter composed of 5 to 20 pores (10 PPI: Pore Per Inch) per inch.

The filter not only increases the surface area at 5-20 PPI pores and controls the flow of molten metal and lowers the inlet temperature by the twisted flow path, but also unreacted sub-materials larger than the pores of the filter are mechanically filtered out of the filter top. You lose.

In addition, the basicity of the slag is 1.5 to 2.5, and the wettability with the ceramic filter is excellent, so that the slag introduced into the interior through the pores is separated from the molten metal by being adsorbed by touching the filter skeleton.

However, if the pore is 5PPI or less, in the slag mixing control, which is the main function of the filter, molten steel and slag are easily mixed and flowed into the basement, and the function of lowering the temperature of the molten steel to lower the molten steel superheat is weakened. Induces turbulent flow of laminar flow to decrease the ability to sequentially charge the molten steel, and if more than 20 PPI is hindered the inflow of molten steel to the unfilled phenomenon of the sample is adverse.

Figure 4 is a cross-sectional perspective view of a sampling port of an embodiment of the present invention, the area of the water flow is larger than the conventional sampling port, (a) is the case where the inside of the lower loss mold is cylindrical, (b) is the bottom This is the case when the inside of the loss mold is a cube.

The tap water 12 of the sampling port communicates with the filter 13 of the chamber 17 and the base 18 so that the molten steel introduced into the chamber 17 is filled into the base 18 through the mouth 11. It is a passage.

It is preferable to form the volume ratio of the water supply 12 to the volume of the basement 18 to 5 to 11%, because the volume of the water supply 12 is less than 5% of the volume of the basement 18. The molten steel of the runway 12 is solidified in advance than the sample of) so that no gas is discharged during the solidification of the sample, so that a cavity is formed in the sample. The discharge capacity is lowered, causing gas defects in the sample.

5 is a view showing the gas outlet 14 provided on the bottom of the lower loss mold 16, (a) is the case where the inside of the lower loss mold is cylindrical, (b) is a cube inside the lower loss mold. If it is.

In the same figure, the lower loss mold 16 is turned upside down, and the gas outlet 14 of the bottom of the lower loss mold 16 has the loss mold 10 so as to smoothly discharge the gas present in the basement 18. It is preferable to form 2 to 4 places with a width and a depth of 1 to 2 mm within a range of -45 ° to + 45 ° based on the imaginary line penetrating the center point and the central opening 11.

The reason for the above is that if the gas present in the chamber is not discharged when the molten steel is discharged, gas defects occur in the sample, resulting in abnormal component analysis, and the reason for limiting the numerical value is that the gas flow path is filled when the molten steel is filled. This is because the gas is concentrated in the front and rear of the inlet, the width and depth of the exhaust hole is limited to the extent that the molten steel flows out so that no disturbance in the transporter and analysis.

6 is a cross-sectional view of a sampling port of another embodiment of the present invention.

As an illustration of the embodiment including both the filter 13, the runway 12 and the gas outlet 14, the technique of obtaining a clean sample by the combination of the above components is maximized.

7 is a state diagram of a sample prepared using the sampling port of the present invention.

(a) is the case where the lower part of a loss is circular, and (b) is the case where the lower part of a loss is hexahedron.

When the molds are removed, the filter 13 remains on the upper portion of the sample 19, and when the mold is cut, the sample is analyzed.

Hereinafter, an Example is described in detail.

Example 1

The results are shown in Table 1 below for the present invention in which the filter is interposed and the working example without the filter. After the molten steel is collected, a healthy sample that can accurately analyze the sample is considered successful, and a case where it is impossible to analyze the component due to the presence of slag mixed in the sample or air bubbles caused by contraction or gas is judged as failed. It was.

Filter presence U radish % Failure 11.6% (7/43) 50% (15/30)

In this experiment, Chi Square statistical verification of the component analysis failure rate according to the filter presence was statistically significant as 0.00, and the presence or absence of the filter was considered to be an important influence factor of the component analysis failure factor.

Example 2

The results are shown in Table 2 below for the operation performed with varying mold heat capacity. After the molten steel is collected, a healthy sample that can accurately analyze the sample is considered successful, and a case where the component analysis is impossible due to the presence of slag mixed in the sample or the presence of air bubbles due to contraction or gas is judged as failed. It was.

Mold heat capacity 46.4 51.4 57.1 % Failure 60.0% (12/20) 28.6% (8/28) 17.2% (5/29)

 In this experiment, the logistic regression of the component analysis failure rate according to the mold heat capacity was statistically significant as P-Value was 0.002, and the heat capacity of the mold was considered to be an important factor in the component analysis failure factor.

The sample obtained by the apparatus of this invention which consists of such a structure goes through the following process.

During the refining of the molten metal, the probe is used to lower the inside of the refining furnace by using an automatic measuring device at the refining position without tilting the refining furnace, and the probe is immersed for about 4 to 5 seconds below about 500 mm from the molten surface. The sample 19 is formed by inflow of molten steel into the basement 18 mounted on the base 18. The sample 19 is collected and separated by taking out the probe, and the solidified portion formed on the loss chamber 17 is artificially removed or cut. After putting the sample in the carrier, it is transferred to the analysis chamber through the pneumatic tube to analyze the molten and final components in refinement.

In the present invention, while the probe is immersed in the molten metal and maintained for about 4 to 5 seconds, the molten metal introduced into the chamber 17 through the spout 11 is passed through the filter 13 and the tumbler 12 to the base 18. It enters and begins to solidify. After stopping for a predetermined time (about 4 to 5 seconds) in the molten metal, when the probe is withdrawn and comes out of the molten metal, the solidified and filled non-solidified molten metal is discharged through the molten iron 11 by the weight of the filter 13 The solidified shape in the basement 18 will be inserted into the sender without any special processing, and if it is immediately inserted into the sender and transferred to the analysis chamber without any additional pretreatment, the waiting time will be reduced after sampling. Surface oxidation and component variation can be reduced.

In addition, the transported sample 19 is cut 17 to 20 mm from the bottom of the sample in the analysis room by a cutter, and then checking whether the joint defects occur on the cut surface is analyzed by the analyzer.

As described in detail above, according to the present invention has the following effects.

First, in the urea process where a large amount of slag is present and oxygen and an inert gas are blown, the urea process is known to be impossible to collect. With the rapid securement of the refining process, the efficiency of refining work is increased by shortening the refining time and the safety and labor productivity of workers are increased by the manual picking work.

Second, the pre-treatment of the collected sample is unnecessary, so the safety of the work is secured and the sample is quickly transferred to the analysis chamber, thereby shortening the processing time and greatly improving the analysis accuracy.

Third, by using a filter to lower the molten steel superheat in a high temperature environment of 1600 ℃ or more to collect a sample for component analysis, prevent the mixing of slag and beautiful surface state of the sample.

Fourth, a gas outlet is provided to remove gas defects in the sample generated by the remaining air in the basement.

Fifth, by controlling the volume ratio of the runway to prevent shrinkage due to coagulation of the runway or defects due to gas.

Claims (10)

A composite probe made of a chamber mold 20 in which a molten steel sample is solidified in communication with the interior of the chamber mold 10 through a loss mold 10 having a molten metal 11 into which a molten metal is introduced, and a tap 12. In the sample collection port for Sample collection port for a composite probe, characterized in that the filter 13 is inserted into the loss mold (10). The method according to claim 1, The filter 13 is a sample collection port for a composite probe, characterized in that the pore is 5-20PPI. The method according to claim 1, The filter 13 is a sample probe for composite probes, characterized in that made of one material selected from zirconia-based, silica-based or alumina-based. The method according to claim 1,  The filter 13 is a sample collection port for a composite probe characterized in that the cylindrical or hexahedral. The sample collection port for a composite probe of claim 1, wherein an outer width of the filter 13 is smaller than an outer diameter of the sample 19, and a length of the sample 19 is 45 to 55 mm. A composite probe made of a chamber mold 20 in which a molten steel sample is solidified in communication with the interior of the chamber mold 10 through a loss mold 10 having a molten metal 11 into which a molten metal is introduced, and a tap 12. In the sample collection port for The water tap 12 is a sample collection port for a composite probe, characterized in that the volume formed of 5 to 11% of the volume of the basement (18). A composite probe made of a chamber mold 20 in which a molten steel sample is solidified in communication with the interior of the chamber mold 10 through a loss mold 10 having a molten metal 11 into which a molten metal is introduced, and a tap 12. In the sample collection port for Sampling port for a composite probe characterized in that the gas outlet 14 is installed on the bottom of the loss mold (10). The method according to any one of claims 1 to 5, The water tap 12 is a sample collection port for a composite probe, characterized in that the volume formed of 5 to 11% of the volume of the basement (18). The method according to any one of claims 1 to 6, Sampling port for a composite probe characterized in that the gas outlet 14 is installed on the bottom of the loss mold (10). The method according to claim 8, Sampling port for a composite probe characterized in that the gas outlet 14 is installed on the bottom of the loss mold (10).

Images