JPS62113063A - Protector for melting mineral immersion type tool - Google Patents

Abstract

PURPOSE:To provide a protector free from the attachment of raw metal, by arranging a ceramic paper layer which is wound on the circumference of a paper tube with the thickness of the layer under 2mm to withstand frequency of molten metal immersions. CONSTITUTION:A ceramic paper 0.1-1mm thick is wound on the circumference of an organic paper tube 7 with the thickness of several millimeter formed by winding strips such as Kraft paper in a tube through an adhesive to provide a ceramic paper with the thickness of up to 2mm. The ceramic paper comprises 50wt% or more of inorganic fiber, 15wt% or less of organic binding component and 35wt% or less of hydration swelling mineral except for asbesto and dispersed thoroughy to make a slurry as material which is worked with a paper maker. This protector is equipped with a thermocouple unit in which a thermocouple is mounted into a housing 3 having a flange 2.

Description

[Detailed Description of the Invention] The present invention relates to a protector for an immersion type tool that is immersed in molten minerals such as molten metal to measure temperature, etc. The present invention relates to a protector for an immersion type tool that is immersed in molten minerals such as molten metal to measure temperature, etc. This invention relates to a protective device for a molten mineral immersion type tool that can be used many times and is provided with a protective layer for protection.

(Prior Art and its Problems) In metal refining, particularly in the steel industry, it has become common to use immersion tools to perform measurements and sampling by immersing them in molten minerals for advanced quality control. A primitive example of protection for this consumable dipping tool is the use of a paper tube.

This is because the heat of the molten metal causes carbonization from the surface, and the carbonized part falls off into the molten metal due to vibrations, the paper tube itself becomes thinner, and new parts of the paper are constantly exposed to high temperatures, thermally decompose, and gas It generated vibrations and splashes constantly in an attempt to instantly release it out of the system.

An immersion type thermocouple described in Japanese Utility Model Application Publication No. 58-9622 is known as an improved example of such a paper tube. This thing is
A thick heat insulating material such as ceramic fiber is used to protect the inside through its heat insulating effect, allowing it to be used many times, and the heat insulating layer needs to be 2 to 20 mm thick. This ceramic fiber protector has drawbacks such as being thick and bulky, making it difficult to extract the exact inner diameter of the cylinder, and making it difficult to fix to the thermocouple body. The ceramic sheet of the prior art is thick and brittle, so when it is attempted to be rolled into a paper tube shape, folds and cracks occur, making it impractical. Making ceramic protectors one by one by corrugating is inefficient and causes high costs. In addition, ceramic fiber is an expensive material, so it actually costs 2~
If the thickness is 20 mm, it will not be within twice the cost i without using it, so even if it can be used many times, the cost per use will be lower than without using this protection device. The result will not change. This point is industrially disadvantageous.

On the other hand, the main material is asbestos, and 5 to 1
A laminated tube made of a sheet containing 5% by weight of inorganic fibers and 5 to 15% by weight of inorganic filler to increase the density is superior as a protective tube to a laminated tube made of a sheet made only of inorganic fibers. It is said that the
It is stated in the No. However, such asbestos-based pipes have the disadvantage that when they are immersed in molten metal during use, metal adheres to the surface of the pipe.

Furthermore, since asbestos is harmful to the human body, the use of asbestos is being avoided, and making asbestos essential is itself a technical drawback.

(Means for Solving the Problems) The present inventors have made extensive studies to solve the problems of the prior art, and as a result, have arrived at the present invention. In other words, even if undeveloped IJI does not use asbestos, it can be rolled up and rolled up by losing the structure of the ceramic paper.
By simply placing a protective layer with a thickness of less than +mm on the paper tube,
It can withstand immersion in molten metal many times, and provides protection four times without splashing or adhesion of bare metal.

The protector for the molten mineral immersion type tool of the present invention basically has the structure shown in FIG. 1, where 7 is a kraft paper tube and 8 is a ceramic paper layer.

A thermocouple using this protective equipment is shown in Figure 2. 1 is a quartz glass tube in which platinum and platinum-rosium thermocouples are inserted, and are connected to the compensation conductor inside the housing 3, with the positive side connected to the connector 4 and the negative side connected to the inner surface of the connector 5. It's out. A protective cap 6 made of a quartz glass tube is attached to the housing flange 2.

The protective equipment is equipped with an organic paper tube 7 as an inner layer, and its wall thickness is determined to be several millimeters or more depending on the thickness and shape of the object to be protected and the usage environment conditions. is adjusted depending on the thickness of the ceramic paper layer further applied on the outside. As the organic paper tube, a so-called paper tube in which a strip of kraft paper or the like is wound into a tube shape with an adhesive is preferably used.

In the conventional immersion type thermocouple using a paper tube as a protector, the ceramic paper layer 8 in FIG. 2 is also made of the paper tube 7.

The ceramic paper rolled up into the ceramic paper layer of the present invention is a thin paper-like sheet in which 50% or more of its weight consists of an inorganic rim (excluding asbestos). These inorganic fibers include high alumina fibers, mullite fibers, silica fibers, quartz fibers, zirconia fibers, alumina-silica fibers, so-called ceramic fibers, rock wool, long glass fibers (chopped strands), and short glass fibers (microglass wool). , mineral wool, carbon fiber, silicon carbide fiber, potassium titanate fiber, etc., but are not limited to these. One type or a combination of two or more of these fi-fi tuna can be used, but the heat resistance temperature is 1000℃.
It is preferable that the following items are mainly used.

In order to form ceramic paper from these inorganic fibers, an organic binding component can be used in a range of 15 weight I11% or less. The organic bonding component is arbitrarily selected from resins and fibers, but preferably used are cellulose fibers treated with mackerel combustion, which are carbonized at high temperatures, cellulose treated with phosphoric acid, cellulose phosphoric acid esterified, phenolic resins, and the like.

Furthermore, by blending water-swellable minerals in an amount of 35% by weight or less, a thin and strong ceramic paper suitable for the purpose of the present invention can be obtained.

Water-use swelling minerals include Ben I/Nite group (colloidal bentonite, colloidal sodium montmorillonite, etc.),
Selected from cloud + 11 (sodium tetrasilicium, sodium or lithium taeniolite, sodium or lithium hectorite, etc.), mountain bark group (seviolite, attapulgite, palygorskite, etc.).

Ceramic paper is made by making a slurry of the above two materials dispersed in water using a paper machine as paper stock. This ceramic paper has sufficient strength even when it is as thin as 0.1 to 1 mm, so it can be easily manufactured into paper on an industrial scale. This ceramic paper can be made to maintain its shape and strength in the range of 500 to 1700°C.

By using such thin ceramic paper, there is no need to use asbestos as in the prior art, and there is no need to increase the thickness of the ceramic layer to 2 to 10 mm. In the present invention, it is sufficient to wrap the ceramic paper in 1 to 10 turns so that the thickness is 0.1 mm or more and less than 2.0 mm.

Ceramic paper with a thickness of 0.1 to 1 mm is used, but 0.1 to 1 mm in thickness is used. A material below the axial layer is preferable because it has flexibility suitable for winding. The ceramic paper layer works effectively by providing the ceramic paper layer only in the required portion depending on the length of the portion of the tool to be immersed in the molten ore. The ceramic paper layer is made of the same ceramic paper wrapped around each other, and the outermost layer is made of ceramic paper with the highest ml heat resistance.
Ceramic paper, which has a slightly lower heat resistance than the outside, can also be used near the paper tube.

The protective device according to the present invention differs from the prior art in that the heat insulating effect is not solely due to the inorganic material layer, and therefore the ceramic paper layer may be thin. When a type thermocouple is immersed in molten steel, heat is transmitted from one surface to the inside, and the internal R
The surface of the paper tube is exposed to high temperatures, but since it is in molten steel, there is almost no oxygen, and hydrogen, oxygen, nitrogen, etc. in the organic matter are thermally decomposed into gases such as water, nitrogen oxide, ammonia, and nitrogen gas. It is released through the ceramic paper layer.

Because it is protected by ceramic paper, unlike when the paper tube comes into direct contact with molten steel, even if thermal decomposition occurs, it progresses slowly and gas is not released into a splash. Carbon remains in the pyrolyzed paper tube, which acts as a heat-resistant insulating material and protects the paper tube inside. Therefore, even if the thickness of the ceramic paper layer is as thin as less than 211II11, it can sufficiently withstand molten steel during use and can be used as a protector for immersion-type tools without splashing.

(Example) In Fig. 1 and Fig. 2, ceramic paper (trade name: Corselan C-15, manufactured by Kojin Co., Ltd.) with a thickness of 0.15 layers, mainly composed of ceramic fibers, is used with an alumina sol adhesive. A ceramic paper layer 8 formed by winding was provided on the outside of a paper tube 7 having a thickness of 5 layers obtained by winding kraft paper in layers using a phenolic resin adhesive. The thickness of the ceramic paper layer of the protective equipment thus formed was 0.9 m. This protection jV 41.
Use 1. As shown in Figure 2, a thermocouple (type thermocouple) is made.
A test was conducted to see how many measurements could be taken at 5-minute intervals using J:91 71111 constant immersion time of 7 seconds. The life of quartz glass /, i= was 5 to 6 times, but the immersion type thermocouple using protection 1 of this example could be used approximately 1 times.

(Effects of the Invention) FIG. 3 is a cross-sectional view after the thermocouple is fitted with the same protective equipment for the immersion type as shown in No. 1 of Kizawa and immersed in molten steel. Inner layer paper tube 7
The thickness of the ceramic paper layer 8 provided on the outer periphery of the paper tube 7 is the minimum required to maintain heat resistance and physical strength. 9 becomes 'If1m2. this is,
This is completely different from the method used in the prior art, where the heat insulating material was kept thick to prevent heat from reaching the organic paper tube; rather, the heat-resistant insulation effect was achieved by changing the surface of the organic paper tube. It is something that causes the expression of

It is useless to design the lifespan of the immersion type equipment to be longer than the lifespan of the equipment itself, so the lifespan of the protective equipment of the present invention is set according to the lifespan of the equipment itself, and it is effective only in terms of performance. It is also highly effective from a cost perspective.

[Brief explanation of drawings]

Figure 1 is a partial cross-sectional view of the protective equipment of the present invention, Figure 2 (A) is an axial cross-sectional view of an immersion type thermocouple equipped with the protective equipment of the present invention, and Figure 2 (B) is a partial cross-sectional view of the same thermocouple. The AA sectional view and FIG. 3 are partial sectional views showing carbonization on the surface of an organic paper tube when the protective device of the present invention is immersed in molten metal. In the figure, l... Quartz glass tube 2... Housing flange 3... Housing 4.5... Connector 6... Protective cap 7... Paper tube 8... Ceramic paper layer 9・・・ Carbon layer

Claims (4)

[Claims] (1) A protector for a molten mineral immersion type tool, characterized by having a ceramic paper layer wound around the outer periphery of a paper tube so that the layer thickness is less than 2 mm. (2) Ceramic paper layer has a thickness of 0.1 to 1.0 m
2. The holder according to claim 1, wherein the holder is made by wrapping 1 to 10 layers of ceramic paper. (3) Claim 1, characterized in that the ceramic paper layer is made of ceramic paper that is sequentially wound from high to low heat resistance from the outside to the inside.
Holder as described in section. (4) The holder according to claim 1, wherein the ceramic paper contains 50% by weight or more of inorganic fibers other than asbestos.