JPH04113069U - Sampler for molten steel - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent metal adhesion and to facilitate sample removal. [Structure] A steel flange ring 2 is attached to the opening of a cylindrical sampler body 1 made of iron, and the outer periphery of the sampler body 1 and the lower part of the sampler support rod 4 are coated with a refractory material such as ceramic 5. [Effect] The steel flange ring prevents pickup of [C] and [N]. Coated refractories prevent metal from adhering. It is easy to remove solidified samples. Suitable for mass online use.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This idea measures [C] in molten steel quickly and with high precision, especially in the low carbon concentration range. Regarding the sampler for this purpose, in more detail, it is necessary to prevent metal from adhering to the iron cylindrical sampler. In addition to attaching a ring to prevent metal from adhering to the sampler body and support rod. This invention relates to a sampler for molten steel coated with a refractory material.

0002

[Conventional technology]

Ultra-low carbon steel generally refers to steel with a composition of [C] < 30 ppm or less, but recently Ultra-low carbonization (e.g. [C]<10ppm-20ppm) and narrow carbon adjustment (e.g. For example, the demand for steel with [C] = 20 ± 3 ppm, [C] = 50 ± 3 ppm) is high. waiting. In order to produce such steel online, [C ] It is necessary to understand accurately. To achieve this, it is necessary to establish a highly accurate and rapid analysis system. We need probabilities and high-precision samplers that are available in large quantities online.

0003 In order to measure [C] in molten steel with high precision and quickly in the low carbon concentration range, it is necessary to It is possible to collect representative samples for steel [C] and quickly submit them for analysis. It is important to be able to analyze these samples with high accuracy and speed. Conventional As a sampler used for online management, it is used to prevent metal adhesion. , a disk sampler with a paper tube designed for ease of sample removal, and a There is a large bomb type sampler, which has molds, ceramics, etc. There are two types made by Kukku.

0004

[Problem to be solved by the invention]

The conventional disk sampler with a paper tube has little metal adhesion and can collect molten steel easily. It has the advantage of being easy to take out, but it is difficult to pick up [C] from the paper tube. and because the amount of molten steel extracted is small, it is vulnerable to contamination, and [C] It has the disadvantage of not being able to ensure sufficient representativeness, making it unsuitable for trace [C] analysis. .

[0005] On the other hand, bomb-type samplers using molds do not have a pickup source for [C]. Since the amount of molten steel to be sampled is also secured, the representativeness of [C] can be ensured at ±2 ppm. In addition, since the heat capacity of the mold is large, a sufficient solidification rate of molten steel is ensured, and the [N] It also has the advantage of being able to secure surface properties of ±2 ppm. However, the mold If the sampler has a large heat capacity, a large amount of metal deposits will occur around the sampler, causing the sampler to It is difficult to remove the cable, and in some cases you may have to cut it to remove it. The drawback is that it is not suitable for mass use on a line.

[0006] In addition, if it is made of ceramic, the carbon content (C, C) in the ceramic is heated to a high temperature. O2, etc.) must be removed, so if the purpose is to analyze trace amounts of [C], a sampler is required. - requires preheating, which poses a problem with workability. In addition, if it is made of ceramic, the heat Due to the small capacity, rapid solidification is difficult and [N] pickup may occur. There was also a problem with the stability of measured values when subjected to analysis.

[0007] This idea solves the problem of the conventional base metal adhesion and the pickup of [C] and [N]. The aim is to maintain workability and reliability when using online. The aim is to provide a highly accurate sampler with high accuracy.

[0008]

[Means to solve the problem]

Although this device has excellent representativeness for [C] and [N], When the type bomb sampler comes into direct contact with the molten steel to be analyzed, [C] is supplied, The advantages of paper tubes and ceramic samplers, which impair the representativeness of [C] The molded bomb sampler is coated with ceramic or other refractory materials. The gist of this is that a flanged steel ring is inserted into the upper opening of the cylindrical sampler body. Attach the sampler through the This is a sampler for molten steel coated with fire.

[0009]

[Effect]

In this design, the opening of the sampler body, that is, the molten steel inlet, is made of steel with a flange. The reason for installing the ring is to keep the sampling port at the [C] or [N] pitch when collecting molten steel. To keep the sample free of clots and to facilitate the removal of clotted samples. This is for the purpose of In addition, from the above point of view, the reason for using steel is that it contains carbon or CO2. Refractories with In addition, we took into account that there is a risk of melting damage for materials with a lower melting point than steel. It is. The height of this steel ring depends on the size of the sampler body. Although slightly different, 18 mm or more is preferable. In other words, if the height is too low, the solidified The connection between the sample and the ring is insufficient, causing the sample to drop when the ring is pulled out. This is because it remains inside the sampler body and cannot be taken out.

0010 In addition, the sides of the sampler body and the bottom of the sampler support rod are coated with refractory material. The reason for this decision is as follows. In other words, as mentioned above, the iron cylindrical sampler has a large heat capacity, so the metal is It adheres to the outer circumferential surface of the sampler, causing the sampler to be wrapped around the sampler and making it difficult to remove the sample. This is because it becomes difficult to reuse, and the metal adhesion makes it difficult to reuse, resulting in high costs. be. On the other hand, when charging the sampler into molten steel, the rod that supports the sampler is Although steel is used, this support rod is also attached to the side of the sampler body. Because of this, it can serve as a base metal attachment point when the sampler is cast with base metal. this Therefore, it is necessary to coat the support rod with refractory material on the part that will be immersed in the molten steel. There is a point. In addition, in the case of a support rod, it will vary slightly depending on the immersion depth of the sampler, etc. Usually, it is preferable to coat the lower part 100 mm or more. Also, fireproof As for the material, ceramic is suitable because it does not cause metal adhesion.

[0011]

【Example】

FIG. 1 is a vertical cross-sectional view showing an example of a sampler for molten steel according to this invention, and 1 is a vertical sectional view showing an example of a sampler for molten steel according to this invention. 2 is a steel flange ring, 3 is a packing, 4 is a support rod, 5 is a sampler body made of is ceramic.

0012 The iron sampler body 1 is bomb-shaped, and a support rod 4 is attached to the side by welding or the like. attached to the body. This sampler body and the lower outer circumference of the support rod are made of ceramic. 5 is coated. The thickness of the ceramic coating is particularly limited. Although it is not intended to be a be. The steel flange ring 2 is inserted into the upper opening of the sampler body 1 as shown in the figure. Since it is installed by fitting inside the sampler, the outer diameter of the part that is inserted into the sampler is the same as the sampler body. The diameter is approximately the same as the inner diameter of the sampler body, and the part of the collar 2-1 is the outer diameter of the opening of the sampler body. The diameter shall be almost the same. Packing 3 is the molten steel from between the sampler body and the flange ring. This is to prevent leakage, and the material used is ceramic.

[0013] When sampling molten steel in a steelmaking furnace, use the support rod 4 to attach the sampler Body 1 is immersed in molten steel and pumped up. At that time, the immersion depth of the sampler body 1 is Needless to say, the depth should not exceed the refractory coating layer of the holding rod 4. melt When extracting steel, the steel ring 2 with a flange attached to the molten steel inlet is used. [C] and [N] are kept in a state without pickup. Inside the sampler body 1 When taking out the solidified sample, use the flange 2-1 of the steel flange ring 2. and can be easily taken out.

[0014]

[Example 1] In order to investigate the effects of different materials for flanged rings, we used an iron sump shown in Figure 1. The main body (inner diameter 30mm, outer diameter 48mm, height 100mm) is made of steel, copper, and ceramic. Mick flange ring (height 26mm, flange outer diameter 35mm, inner diameter metal 26mm) 30 samples were taken for each ring. Table 1 shows the results of investigating the analysis accuracy and sample pullability of [C]. vinegar. Sampling was carried out in a ladle after decarburization at RH. The [C] level at that time was [C]=10 to 25 ppm. Also, on the sampler body and support rod. was coated with a 3 mm thick ceramic layer. From the results in Table 1, the sample It can be seen that the steel ring is the best in both the pull-out rate and the variation in [C].

[0015]

[Table 1]

[0016]

[Example 2] In order to investigate the effect of different heights of the flanged steel ring, the same sample as in Example 1 was used. Ring height on the puller body is 10mm, 15mm, 18mm, 23mm, 26mm Table 2 shows the results of examining the number of samples pulled out by varying the conditions. In this example, Twenty samples were taken for each. The flange and inner diameter of the steel ring used are the actual The dimensions were the same as in the example. From the results in Table 2, the height of the steel ring is 18 mm or more. It can be seen that the above is effective.

[0017]

[Table 2]

[0018]

[Example 3] In order to investigate the effect of the presence or absence of refractories, a steel sachet of the same size as in Example 1 was used. With and without ceramic coating on the sampler body and support rod. Table 3 shows the results of examining the metal adhesion status and analysis accuracy of [C] for each case. sa The coating thickness on the main body of the sampler was 3 mm in all cases. sample In the tundish of a continuous casting machine, target molten steel with [C] = 10 to 25 ppm. Each was performed 20 times. From the results in Table 3, it can be seen that the variation in [C] In this case, there is almost no difference in superiority, but in order to prevent metal adhesion, Coating the refractory body and the lower part of the support rod 100mm or more with refractory material. It turns out that this is necessary.

[0019]

[Table 3]

[0020]

[Effect of the idea]

As mentioned above, this idea involves attaching a steel ring to the iron sampler body. Coating the puller body and the lower part of the support rod with ceramic or other refractory material. This has a great effect of preventing metal adhesion, and also eliminates the pickup of [C] and [N]. This allows for good workability and high sample accuracy, making it suitable for trace [C] analysis and online analysis. It is highly effective when using large amounts of water.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an example of a sampler for molten steel according to the invention.

[Explanation of symbols]

1 Sampler body 2 Ring with flange 3 Packing 4 Support rod 5 Ceramic

Claims (1)

[Scope of utility model registration request] Claim 1: In an iron cylindrical sampler for collecting molten steel, a flanged steel ring is attached to the upper opening of the sampler body via a packing, and a refractory is coated on the side surface of the sampler body and the lower part of the sampler support rod. A sampler for molten steel characterized by: