KR20110026283A - Automatic sampler for analysis of inclusions - Google Patents

Abstract

PURPOSE: An automatic sampler for inclusion analysis is provided to prevent defects in the manufacture of high clean steel by producing sound samples having the representative nature of molten steel. CONSTITUTION: An automatic sampler for inclusion analysis comprises a main body(100), a sampling case(120), and a multilayer protecting pipe. The sampling case is built in the main body. The multilayer protecting pipe surrounds the outside of the main body. The sampling case is installed in the lower part of the main body. An inlet groove(124) is formed so one side of the sampling case is opened and the molten steel flow therein. An inlet port(130) for molten steel is formed downward. The upper end of the inlet port connects to the inlet groove of the sampling case.

Description

AUTOMATIC SAMPLER FOR ANALYSIS OF INCLUSIONS}

The present invention relates to an automatic sampler used to measure the composition of molten steel in the steelmaking process, and more particularly, to prevent the contamination of the sample by contamination sources such as external inclusions in the sampling process to obtain a healthy sample having a representative representative of molten steel An automatic sampler for inclusion analysis to be obtained.

In general, the steelmaking process mixes molten iron and scraps from the blast furnace to refine and purify pure oxygen, argon, nitrogen, etc. by up-and-down transverse side, at which time, raw materials (flux) to separate or float impurities from the steel One of the most important processes in the integrated steel mill is to refer to a series of operations to adjust the composition of the product by adding and adjusting a special alloy that is suitable for the steel composition.

In such a steelmaking process, it is very important to manufacture high quality steel by increasing the cleanliness of molten steel, and it is the inclusion that has a great influence on the cleanliness of the molten steel, and the source of the inclusion is a foreign substance generated during the steelmaking process until the molten steel solidifies. Residues in these materials include oxides, carbides, sulfides, nitrides, and phosphides, and the amount, size, shape, and physical properties of these residues greatly affect the mechanical properties of the steel, and when these inclusions are not properly controlled, Impact value, formability, fatigue strength decrease, anisotropy increase, notch effect, etc., and work defects such as surface defects such as hot-rolled and cold-rolled material defects, disconnection during wire rod processing, and operation obstacles such as nozzle blockage. .

On the other hand, there are many ways to evaluate the inclusions that affect the cleanliness of molten steel, but in general, the cleanliness of molten steel is evaluated based on the total oxygen content (Total- [O]) in the molten steel. Is a very important measure. However, in order to perform the cleanliness evaluation by this method, a sampling operation of collecting a sample of molten steel must be performed first, and the integrity of the sampled sample is most important for accurate cleanliness evaluation.

The conventional manual sampling method is difficult to standardize the sampling position, immersion depth, and pressure that can be continuously immersed in the surface of molten steel, so that it is difficult to secure representativeness of molten steel, such as variation of components even during sampling process of the same molten steel. Since the sampling itself is also a process that requires considerable effort, there is a problem that the load is increased. Therefore, there has been a demand for an automatic sampler that can secure the integrity of the sample and more accurately measure the cleanliness of molten steel to solve the problems of the manual sampling method.

In addition, as a conventional general sampling method, there is a sampler in which the inlet port of the molten steel for sampling is formed on the side of the sampler so that the molten steel can be contained in the sampling case through the inlet port. Because of the high risk of incorporation of contaminants such as oxidative inclusions in the refractory cement and sampling case coated on the inner surface of the sample, inevitably contaminates the sample. There is a problem that must be reached but does not meet the required depth of immersion.

Although molten steel is introduced from the lower end of the sampler and the molten steel filled in a small disk (DISK) mold by static pressure is used, it is suitable as a chemical analysis sample by surface analysis, but the volume of the sample There is a problem such as non-uniform distribution of inclusions, segregation due to the difference in molten steel temperature and cooling rate.

The present invention has been made in order to solve the above-mentioned conventional problems, it is possible to automatically measure, to prevent the contamination of the sample by the contamination source, such as interposition properties when collecting the sample to obtain a sound sample with a representative representative of the molten steel, It is an object of the present invention to provide an automatic sampler for inclusion analysis, which can accurately evaluate the type and amount of inclusions and solve the problem of uneven distribution and segregation caused by the small sample volume.

The present invention provides a sampler including a main body, a hollow sampling case embedded in the main body, and a multilayer protective tube surrounding an outer side of the main body, wherein the sampling case is disposed below the main body, and the sampling case is lost. An inlet groove is formed so that one side of the inlet is opened so that the molten steel is introduced, and an inlet of the molten steel is formed downward in one lower portion of the main body, and an upper end of the inlet communicates with an inlet of the sampling case, and a lower end of the main body. An outer cap is opened at the tip, and an outer cap is formed to cover the tip opening of the main body to protect the inlet. A connector for receiving inclusion communication is formed at an upper side of the sampling case. do.

In this case, the inlet groove is also characterized in that the lower end is formed of a "∩" shape.

In addition, the size of the inlet groove is characterized by 8 to 10 mm.

In addition, the upper end of the sampling case is characterized in that at least one gas discharge hole is formed through.

In addition, the upper end of the inlet is characterized in that it has a constant radius of curvature and communicates with the inlet groove of the sampling case.

In addition, the outer cap is characterized in that it has a double structure consisting of a paper cap of the outer portion made of paper, and a metal cap of the inner portion made of metal.

In addition, it is also characterized in that it further comprises an inner cap covering the lower end of the inlet.

In addition, the outside of the inlet is characterized in that the finish treated with heat-resistant cement.

The present invention by the problem solving means to improve the filling rate of the molten steel, to prevent the contamination of the sample by the contamination source, such as external inclusions in the sampling process, by taking a very clean sample, to obtain a sound sample with a representative representative of the molten steel As a result, it is possible to prevent defects in the production of high-purity steel in advance, furthermore, to provide an excellent effect of eliminating product strength and obstacles in post-processing.

Hereinafter, the present invention will be described in detail with reference to the drawings.

1 is a front sectional view of an automatic sampler according to the present invention, FIG. 2 is an enlarged view of a sampling case portion of the present invention, and FIG. 3 is an enlarged view of a main body tip portion of the automatic sampler of the present invention.

As shown in FIG. 1, the automatic sampler for inclusion analysis according to the present invention includes a sampler body 100 in which a plurality of components are embedded for sampling, and a hollow sampling is provided below the sampler body 100. The case 120 is built in. The sampling case 120 is divided into an upper chamber 121 and a lower chamber 122. The diameter of the lower chamber is configured to be somewhat larger than the diameter of the upper chamber. In addition, an inflow groove 124 is formed to open a portion of one side of the loss chamber 121 so that molten steel flows from the inflow port 130, and in some cases, it is necessary to minimize the outer diameter of the main body 100. Since the inlet 130 of the shape of the child should be made as close to the mold as possible, the inlet groove 124 is preferably formed in a "∩" shape with the bottom closed as shown in the "side enlarged shape" of FIG. Do. Here, the size of the length (a) and the length (b) of the inlet groove 124 is preferably 8 to 10 mm, which is to receive a proper pressure from the inlet 130 to greatly improve the fillability of the molten steel For sake. In addition, the inflow groove 124 may be made of quartz, thereby reducing pollutant discharge.

In addition, the gas discharge hole 123 is formed through the upper end of the loss of the sampling case 120, so that when the gas bubbles rise to the upper side in the sampling case 120 to be separated, the vent may be smooth. By controlling the gas defects, the analytical surface is smoothed when luminescence analysis of the sample is obtained to obtain more accurate analytical values.

At this time, the material of the sampling case is preferably made of steel similar to the material of molten steel, by being made of the steel material is minimized the contamination of the sample for component analysis, it is possible to collect a highly clean sample.

In addition, the inlet 130 of the molten steel is formed downward in a vertical direction by opening a portion of the protective tube 110 at one lower portion of the sampler main body 100, and the upper end of the inlet 130 has a constant radius of curvature. It communicates with the inlet groove 124 of the sampling case 120, the lower end is opened to the front end 140 of the main body is formed to be open, and eventually have an "L" shape. At this time, it is preferable that the inlet 130 is formed so as to protect the inlet 130 by closing the portion of the protection tube with a heat-resistant cement. In addition, since the material of the inlet is made of a quartz tube, the melting of the tube can be minimized even at a high temperature molten steel, so that it can be used without the discharge of contaminants.

And, as shown in Figure 3 in order to protect the inlet 130, the conical outer capping (capping) covering all the openings of the tip 140 of the main body, including the inlet 130, the inner cap 161 Cap 160 is formed. This is because it is preferable that the automatic sampler of the present invention is formed in a conical form that can be stress concentrated so that it can easily pass through the slag layer. At this time, the inner cap 161 is also capped at the lower end of the inlet 130 to form a double capping structure of the inner cap 161 and the outer cap 160 so that the inlet 130 is immersed in the molten steel. At this time, it is preferable to protect the inlet from the slag and prevent the inclusions floating on the surface of the molten steel from flowing into the inlet 130 to impair the integrity of the sample. Here, the outer cap 160 has a double structure of the paper cap 163 made of paper and the metal cap 162 of the inner portion made of metal, the metal cap when the automatic sampler is immersed in the molten steel Delay the time 162 melts. In addition, the metal cap 162 is a steel cap made of steel, the steel cap is made of ULC (Ultra Low Carbon steel) is preferable because the deviation of the total oxygen amount of the molten steel is reduced. In addition, the paper cap 163 is coupled in a shape surrounding the outer surface of the metal cap 162.

In addition, the automatic sampler for inclusion analysis according to the present invention is provided with a protective tube 110 surrounding the outer periphery of the main body 100. As shown in FIG. 1, the protective tube 110 has an outermost shell. It is made of a ceramic fiber 111 having a good thermal shock resistance, the inner shell is coupled to the inner surface of the shell is a paper pipe (紙 管), the branch pipe is an outer branch pipe 112 and the inner surface of the ceramic fiber 111 and coupled It is made of a multi-layered structure consisting of the inner tube 113 coupled to the inner surface of the outer tube to protect the sampler immersed in the molten steel of high temperature. At this time, the branch pipe uses wound paper, and the ceramic fiber of the outermost layer is composed mainly of alumina or silica sand.

In addition, a connector 150 is provided on an upper side of the sampling case 120, and when a holder (not shown) is mounted on the main body 100, the holder 150 is electrically connected to the conductor so that the holder is connected to the connector 150. The connector 150 is configured to receive a communication call.

Hereinafter, the operation relationship of the present invention will be described.

When the automatic sampler for inclusion analysis according to the present invention is immersed into the molten steel to a depth capable of collecting a healthy sample, first pass through the slag layer of the upper, then the paper cap 161 formed at the bottom of the tip 140 of the main body This primary combustion is followed, and the metal cap 162 is melted next. The molten steel is injected into the inlet groove 124 of the upper chamber 121 of the sampling case 120 through the inlet 130, and filled in the chamber 122, and the molten steel solidifies while cooling the chamber 122. When the sampling is completed as described above, the holder is raised and then the main body 100 is detached from the holder and transferred to the analysis chamber to analyze the inclusions.

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

Figure 4 is a photograph of the samples taken by the present invention and the comparative example, Figure 5 is a comparative analysis graph of the component value and the carbon (C) component of the contrast test according to an embodiment of the present invention.

Table 1

Table 1 shows the molten steel inflow direction of the automatic sampler and the comparative sampler according to the present invention, the material of the inlet, the material of the loss and the basement, the material and size of the inlet groove, the material of the inner cap.

As a result of taking a sample according to the specification of Table 1, as shown in Figure 4, both the invention and the comparative example did not have a big difference in the degree of filling, as shown in Table 2, reproducibility for evaluating the cleanliness of molten steel Difference in the degree of contamination, variation of components, etc.

[Table 2]

Table 2 compares the analysis values of each of the execution types (A, A-1, B, B-1) with a conventional disk (DISK) sample for the optimization of the execution types of Table 1.

Herein, the amount of oxygen in inclusions in the reproducibility section refers to the amount of oxygen present in inclusions among the analysis values of each embodiment type based on the representative sample of the conventional disc-shaped sample. , 'Variation of inclusion area' item is an evaluation of the variation of the area of inclusions between collections in consideration of the analysis method of inclusions, which is analyzed several times, and the composition ratio of Al ₂ O _{3 in} inclusions in the 'degree of pollution' section. And 'AlCaMgO composition ratio among the inclusions' item is to compare the proportion of Al ₂ O ₃ and AlCaMgO present in the total inclusions compared to the reference sample to confirm the degree of pollutants introduced from the outside, size distribution ”item is to check the size of inclusions and to check the segregation, which is a sample defect that occurs during solidification. In the 'component' section, 'carbon [C]' compares the degree of pick up of carbon with reference value. Will.

In this case, the evaluation item '○' is a case of statistically approximating the reference value, '△' is a case of statistically similar to the reference value, 'x' means that the reference value is different.

As shown in the results of Table 2, the inflow direction of the molten steel as the type A corresponding to the invention example, the inlet is a quartz material, the loss and the base plate is plated with Ni, the inlet groove is a quartz material and its size In the case of ULC (Ultra Low Carbon steel), the inner cap is ultra low carbon steel, the amount of oxygen in inclusions, the variation of inclusion area between analysis, composition ratio of Al2O3 and AlCaMgO in inclusions, size distribution of inclusions, carbon The pick-up amount of is shown as a reference value and an approximation value to obtain a healthy sample having a representative of molten steel.

In particular, as shown in the diagram of FIG. 5, the type A using the ULC of the present invention was found to be much closer to the reference value of the sample having excellent representativeness in the DISK sample than the other comparative example using the paper cap. When the cap is used as a ULC, which is an ultra low carbon steel, the carbon pick-up amount is small, and when the conventional paper cap is used, the carbon [C] pick-up amount is large.

[Table 3]

Table 3 compares the total oxygen content (Total- [O]) in the molten steel of type A according to the present invention with a disk sample, and the 'viewpoint' item in Table 3 is inputted to the molten steel during the treatment process. The time since the second is expressed in seconds. Ti acts as a deoxidizer because it is a highly reactive element with oxygen. Therefore, after Ti is injected into molten steel, the compound of Ti and oxygen rises as a slag and is separated, thereby reducing the total amount of oxygen with time. As shown in Table 3, since the component deviation of the total oxygen amount is insignificant, it can be confirmed that in the case of the type A of the present invention, there is little contamination by inclusions, so that a healthy sample can be obtained.

1 is a front sectional view of an automatic sampler according to the present invention.

2 is an enlarged view of a sampling case portion of the present invention.

3 is an enlarged view of a main body tip portion of the automatic sampler of the present invention.

Figure 4 is a photograph of the samples taken by the present invention and the comparative example.

5 is a comparative analysis graph of the carbon component (C) of the component value and comparison experiment according to an embodiment of the present invention.

* Description of the major symbols in the drawings *

100. Sampler Body

110. Protective tube 111. Ceramic fiber

112. Outside Branch 113. Inside Branch

120. Sampling Case 121. Loss

122. 123. Gas outlet hole

124. Inlet 130. Inlet

140. Tip of the sampler body 150. Connector

160. Outer Cap 161. Inner Cap

162. Metal Cap 163. Paper Cap

170. Opening at the tip of sampler body

Claims (8)

In the sampler provided with a main body, the hollow sampling case built in the said main body, and the multilayer protective tube surrounding the outer side of the said main body, The sampling case is installed in the lower portion of the main body, an inlet groove is formed so that one side of the loss of the sampling case is opened to introduce the molten steel, The inlet of the molten steel is formed downward in one lower portion of the main body, the upper end of the inlet is in communication with the inlet groove of the sampling case, the lower end is opened to the front end of the main body, An outer cap is formed to cover the tip opening of the main body to protect the inlet. Automatic sampler for inclusion analysis, characterized in that the upper side of the sampling case is formed with a connector receiving a communication call. The method of claim 1, The inlet groove is an automatic sampler for inclusion analysis, characterized in that consisting of a closed "∩" shape. The method of claim 1, Size of the inlet groove is an automatic sampler for inclusion analysis, characterized in that 8 ~ 10 mm. The method of claim 1, Automatic sampler for inclusion analysis, characterized in that at least one gas discharge hole penetrates the upper end of the sampling case. The method of claim 1, Automatic sampler for inclusion analysis, characterized in that the upper end of the inlet has a constant radius of curvature and communicate with the inlet groove of the sampling case. The method of claim 1, The outer cap is an automatic sampler for inclusion analysis, characterized in that the dual structure consisting of a paper cap of the outer portion made of paper, and a metal cap of the inner portion made of metal. The method of claim 1, Automatic sampler for inclusion analysis further comprises an inner cap covering the lower end of the inlet. The method of claim 1, Automatic sampler for inclusion analysis, characterized in that the outside of the inlet is finished with heat-resistant cement.

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