JPH08278302A - Molten metal sampling device - Google Patents

Abstract

(57) [Summary] [Purpose] A sample for instrumental analysis and a sample for gas analysis are collected at the same time, and in particular, the sample for gas analysis is prepared in a short time. [Structure] A cup-shaped collection container 12 made of refractory brick is fixed to a tip of a holder 11 made of an iron rod. A hole 13 is formed at the bottom of the sampling container 12, and a gas analysis sampling tube 14 made of a quartz tube having a small diameter at the tip and having heat resistance is inserted into the hole 13 from above. At the time of sampling, the molten steel is pumped up from the opening of the sampling container 12, the sample is taken out after solidification, the sample in the sampling container 12 is used for instrumental analysis, and the sample in the gas analysis sampling tube 14 is used for gas analysis.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is directed to component analysis of molten metal,
The present invention relates to a molten metal sampling device for sampling for gas analysis.

[0002]

2. Description of the Related Art Conventionally, in processes such as smelting and steel making, it is essential to analyze the components of hot metal, molten steel and the like. For the preparation of the sample for the component analysis, for example, a sampler 1 as shown in FIG. 7 is used to pump up molten steel to collect a substantially cylindrical metal sample S as shown in FIG. 8, and this metal sample is shown in FIG. Cut into round slices with a grindstone cutter.

Then, the thick sample S1 is subjected to instrumental analysis such as vacuum spectroscopic analysis and fluorescent X-ray analysis to determine the contained components. Further, the thin sample S2 is further cut into a prismatic sample S3 as shown in FIG. 10, and this sample S3 is further provided as shown in FIG.
Is cut into a cube having a side of about 5 mm and a weight of about 0.5 to 1 g, which is used as a gas analysis sample S4 by a combustion method.

Of course, there is a sampler dedicated to the gas analysis sample, but the sample must be collected separately from the instrument analysis sample, and it is difficult to attach the sample collection point and the collection time, which is expensive. There are drawbacks.

[0005]

However, in the above-mentioned conventional example, adjustment of the small gas analysis sample S4 is extremely troublesome, not to mention the instrument analysis sample. In particular, cutting and polishing require skill, and it takes about 15 minutes to prepare the sample.

The object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide a molten metal sampling device capable of simultaneously collecting an instrumental analysis sample and a gas analysis sample, facilitating adjustment of the gas analysis sample, and obtaining an accurate measurement value.

[0007]

In order to achieve the above object, a molten metal sampling apparatus according to the present invention is provided with a hole in the bottom of a cup-shaped sampling container and a quartz tube with a small tip at the hole. It is characterized in that it is attached by inserting it downward.

[0008]

In the molten metal sampling apparatus having the above-mentioned structure, the molten metal is pumped up into the cup-shaped sampling container, the metal sample is taken out from the cup-shaped sampling container and the quartz tube after cooling, and the sample in the cup-shaped sampling container is subjected to instrumental analysis. The sample in the quartz tube is used for gas analysis.

[0009]

Embodiments of the present invention will now be described in detail with reference to FIGS. 1 to 6 and data. 1 shows a cross-sectional view,
A cup-shaped collection container 12 made of, for example, refractory brick is fixed to the tip of a holder 11 made of an iron rod or the like. A hole 13 is formed at the bottom of the sampling container 12 by, for example, a drill, and a gas analysis sampling pipe 14 made of a quartz tube having a small diameter at the tip and having heat resistance is directed downward from the inside of the sampling container 12. Have been inserted.

As shown in FIG. 2, the gas analysis sampling tube 14 is
The central portion of the quartz tube 14 'having an inner diameter of about 5 mm is heated to form a small diameter, and this portion is cut to obtain two gas analysis sampling tubes 14 as shown in FIG. Then, the base ends of these gas analysis sampling tubes 14 are expanded into a trumpet shape, and one of the gas analysis sample tubes 14 is placed in the hole 13 of the sampling container 12.
It is inserted so that it does not fall downward from above. In this case, assuming that the inner diameter of the quartz tube 14 is D and the inner diameter of the thin portion is d, it depends on the type of molten metal, the temperature of the molten metal at the time of sampling, etc., but normally d / D is 0.01-0.5, preferably 0.03-0.
2 is good.

In use, when holding the holder 11 and immersing the sampling container 12 in the molten steel, the molten steel enters the inside of the sampling container 12 through the upper opening and further flows into the sampling tube 14. Therefore, when the sampling container 12 is pulled up, since the tip of the gas analysis sampling tube 14 has a small diameter, the molten steel can be pulled up without dropping.

After a lapse of some time, the solidified metal sample is taken out from the inside of the collection container 12 together with the collection pipe 14. Therefore, when the collection pipe 14 is broken, a solidified metal sample S as shown in FIG. 4 is obtained.

Therefore, as shown in FIG. 5, a metal sample is cut and a sample S5 obtained from the sampling container 12 is used as a sample for instrumental analysis, and a sample S6 obtained from the gas analysis sampling tube 14 is used.
After polishing the periphery, cut as shown in FIG.
The sample S7 of about 1.0 g is prepared and used as a sample for gas analysis.

Next, when the molten metal sampling apparatus was actually used, the data as in the following Examples 1 and 2 were obtained.

Example 1 A sampling container 12 made of refractory bricks having a thickness of 7 mm and having an inner diameter of 37 mm and a height of 85 mm was used, and a hole 13 at the bottom thereof had an inner diameter of 6 mm, an outer diameter of 8 mm, and a length of 90 mm. The gas analysis sampling tube 14 having an inner diameter of 0.3 mm was attached downward, and the holder 11 was an iron round bar having an outer diameter of 8 mm and a length of 720 mm.

Sampling was performed in a 30 ton AOD furnace for refining 3
The molten steel in the tundish when the molten steel was transferred from the ladle to the tundish during continuous casting of 04 stainless steel was performed in the following procedure. (1) The molten steel was transferred from the ladle to the tundish, and 5 to 6 minutes after starting the injection from the nozzle into the continuous casting mold, the slag floating on the surface of the molten steel in the tundish was quickly scraped off, and the temperature was set to 1530. Exposing the molten steel surface at ℃. (2) Hold the holder 11 at the place where the slag has been scraped, and push the sampling container 12 almost vertically into the molten steel to draw the sampling container 1
The top part of 2 is immersed to a depth of 2-3 cm from the surface of the molten metal. (3) After 2 to 3 seconds have passed, the sampling container 11 is pulled up from the molten steel. (4) Immediately water-cool the sampling container 11 in which the sample molten metal is collected, and then transport it to the analysis room. (5) In the analysis room, the collection container 11 is broken and the sample is taken out. (6) After the surface of the sample S6 obtained in the portion of the gas analysis sampling tube 14 is cleaned, it is cut into about 1 g by a hydraulic rebar cutter, and hydrogen S (H), nitrogen (N) and oxygen (O) are cut out. The sample is S7 for gas analysis. Further, the sample obtained in the sampling container 11 is made into a sample S5 having a thickness of about 20 mm by a grindstone cutter and used for fluorescent X-ray analysis for analyzing components other than gas. For comparison, a sample for gas analysis of hydrogen (H), nitrogen (N), and oxygen (O) is also cut out from the sample S in the collection container 11.

The following Table 1 shows the gas components of the sample, that is, hydrogen (H), nitrogen (N), and oxygen (O), the sample S6 obtained by the gas analysis sampling tube 14 and the conventional method. 3 is a comparison of the gas analysis values of the sample (B), which is the sample S5 in the sampling container 11 corresponding to the above. Each of the six samples was analyzed twice to examine the variation in the analysis values.

[0018]

[Table 1]

As a result, the values of hydrogen (H), nitrogen (N), and oxygen (O) are smaller in the sample (A) than in the sample (B). It has been found that the variation of is extremely small.

It is considered that the reason for this is that the sample (A) is less contaminated than the sample (B) at the time of collecting the molten metal or cutting out the sample, but in any case, it is gas. It was confirmed that the gas component can be analyzed more accurately by using the sample (A) obtained in the analysis sampling tube 14.

Example 2 Sampling was performed in a 1.5 ton vacuum refining furnace on 316 stainless steel by the following procedure. (1) The sampling container 11 is installed on a sampler mounting jig of a 1.5 ton vacuum melting furnace. (2) After closing the door of the raw material addition tank where the mounting jig is installed, decompress the furnace. (3) Argon gas is introduced to keep the vacuum in the furnace constant. (4) Open the gate valve of the raw material addition tank,
Is dropped into the molten steel at a temperature of 1645 ° C. (5) The sampling container 11 is pushed almost vertically into the molten steel, and the top part of the sampling container 11 is immersed to a depth of 2-3 cm from the molten metal surface. (6) After 2-3 seconds, the sampling container 11 is pulled up from the molten steel. (7) Fill the atmosphere after closing the gate valve of the raw material addition tank. (8) Open the door of the raw material addition tank and remove the sampling container 11 from the mounting jig. (9) Immediately put the sample container 11 in which the sample has been collected in water to cool it, and then transport it to the analysis room. (10) Break the sampling container 11 in the analysis room and take out the sample from the inside. (11) In the same manner as in Example 1, two types of samples (A) and (B) are prepared.

In Table 2, as in the case of Example 1, hydrogen (H),
Samples (A) and (B) for nitrogen (N) and oxygen (O)
It is a comparison of the gas analysis values of.

[0023]

[Table 2]

As a result, as in the case of Example 1, the sample (A) was obtained at any of the values of hydrogen (H), nitrogen (N) and oxygen (O).
It was found that the variation was smaller than that of the sample (B), and the variation of the oxygen (O) value was extremely small.

Therefore, also in this Example 2, the sample (A)
It was revealed that the gas components can be analyzed more accurately by using.

[0026]

As described above, the apparatus for collecting molten metal according to the present invention is capable of collecting a sample for instrumental analysis and a sample for gas analysis at the same time, and in particular, adjustment of the sample for gas analysis is easy and accurate measurement values are obtained. There is an advantage that can be obtained in a short time.

[Brief description of drawings]

FIG. 1 is a sectional view.

FIG. 2 is an explanatory view of manufacturing a sampling tube for gas analysis.

FIG. 3 is a cross-sectional view of a sampling tube for gas analysis.

FIG. 4 is a perspective view of the obtained metal sample.

FIG. 5 is a perspective view showing a state in which a metal sample is cut.

FIG. 6 is a perspective view of a cut gas analysis sample.

FIG. 7 is a sectional view of a conventional sampler.

FIG. 8 is a perspective view of the obtained metal sample.

FIG. 9 is an explanatory diagram in which a metal sample is cut with a grindstone cutter.

FIG. 10 is a perspective view of a prismatic sample being adjusted.

FIG. 11 is a perspective view of a sample for gas analysis.

[Explanation of symbols]

 11 holder 12 sampling container 13 hole 14 gas analysis sample tube

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Eiichi Nakano Watanabe, Aomori Prefecture Kawaraki Toyama Nitta (no address) Ohira Metals Co., Ltd. Hachinohe Works (72) Inventor Shinzaburo Nakaya Taito, Taito-ku, Tokyo 6th-6th Riken Kogyo Co., Ltd. (72) Inventor Isao Tanaka 1-6-6 Taito, Taito-ku, Tokyo Riken Kogyo Co., Ltd.

Claims (3)

[Claims] 1. A hole is provided at the bottom of a cup-shaped collection container,
A fused metal sampling device, characterized in that a quartz tube having a thin tip is inserted into the hole and is attached downward. 2. The base of the quartz tube is expanded into a trumpet shape,
The molten metal collecting device according to claim 1, wherein the quartz tube is inserted into the hole from above. 3. The molten metal sampling device according to claim 1, wherein a rod-shaped holder is fixed to the cup-shaped sampling container.