KR200193056Y1 - Thermocouple of continuous casting mould - Google Patents

Abstract

The present invention relates to a thermocouple for measuring copper plate temperature of a continuous casting mold, which can measure the copper plate temperature of the mold more accurately and the insertion time of the thermocouple can be made much faster than the conventional method.

The present invention is a thermocouple for measuring the copper plate temperature of a continuous casting mold, having a conical outer circumferential surface, a hollow space is formed inside, Cu ring member is drawn out to form a + electrode on one side ; A constantan wire for inserting a tip into the hole of the Cu ring member to be welded to form a thermocouple, and drawing the coating material of an insulating material on the outer circumferential surface of the outside of the hole to form an electrode; A filler filling the hole to insulate the Cu ring member and the constantan wire while insulated; It provides a thermocouple for copper plate temperature measurement of the continuous casting mold, characterized in that it comprises; and the Cu ring member and constantan wire, and the bolt is mounted to the mold having a hollow hole containing the filler.

Description

Thermocouple for Copper Plate Temperature Measurement of Continuous Casting Mold

The present invention relates to a thermocouple for measuring the copper plate temperature in a continuous casting mold, and more particularly, a continuous casting mold in which the thermocouple is inserted more rapidly than the conventional method while measuring the copper plate temperature of the mold more accurately. It relates to a thermocouple for measuring copper plate temperature.

In general, by measuring the copper plate temperature in the continuous casting mold of steel, it is possible to predict the breakout, that is, cast burst, occurring in the mold. In particular, the copper plate temperature is essential for high-speed casting or casting steel grades that are sensitive to cast rupture. Although the copper plate temperature measurement may play an important role in continuous casting in principle, it is difficult to measure the temperature in full scale due to the following problems in practical use. The first problem is that conventional methods for inserting a thermocouple into a continuous casting mold require a lot of time and processing cost. The second problem is that after inserting the thermocouple into the mold, water can seep around the thermocouple during continuous casting, so that accurate temperature measurements cannot be made.

In the case of continuous casting mold, as shown in FIG. 5, a high pressure cooling water is supplied to a steel water jacket through a cooling water channel, and the steel water jacket A copper mold is positioned inward of the c), and the copper plate forms a rectangular cross section inside, whereby molten steel is cast. In addition, since bolts and various mechanical devices for fastening the copper plate and the water cooling jacket are complicated, it is very difficult to insert a plurality of thermocouples into the copper plate as shown in FIG. . The most common method for inserting a thermocouple into a copper plate in a mold is to drill a hole in the bolt (5) connecting the copper plate (1) and the water cooling jacket (3) and insert the thermocouple (4) therein as shown in FIG. will be. In this method, the copper plate 1 and the water cooling jacket 3 do not need to be processed separately, and since the tension bolt 5 is very tightly inserted in the mold, the thermocouple 4 can be easily selected. However, this method has a problem in that if the tension bolt 5 and the mold copper plate 1 cannot be completely sealed, the coolant 2 penetrates therebetween, thereby degrading the accuracy and sensitivity of the measured values. In addition, the thermocouple 4 usually uses stainless steel (K) (Chrommel-Alumel) or T (Copper-Constantan) type, and since the stainless steel having poor thermal conductivity is located between the copper plate (1) and the thermocouple (4). There is a problem that cannot be measured sensitively. Therefore, there is a problem in that the thermocouple 4 cannot be monitored even if breakout occurs when the cast piece breaks in the mold because the reactivity of the thermocouple 4 is low.

On the other hand, as a method of improving the sensitivity of the thermocouple 4, there is a method of measuring the temperature by forming a thermocouple by welding a constantan line of a T (Copper-Constantan) type thermocouple to a copper plate 1 whose main component is Cu. In this method, the temperature can be measured sensitively because the welded spot forms the thermocouple (4), but before welding, the coating on the copper plate (1) must be removed. The copper plate (1) and the water cooling jacket (3) It is very difficult to remove the film in the bonded state, and it is difficult to completely remove the water before welding. If water penetrates between the bolt (5) and the copper plate (1), remove the welded constantan wire and drill the welded part. Open and weld again. If this is repeated, there is a problem in that the thickness of the copper plate 1 at the position where the thermocouple 4 is inserted becomes thin and the copper plate life is shortened. In addition, since the copper plate 1 of the welded thermocouple is not pure copper, there is a problem in that accurate temperature cannot be measured.

As another method of inserting the thermocouple 4 into the mold, there is a method of inserting the thermocouple 4 by directly drilling a hole in the casting direction from the upper part of the copper plate 1 as shown in FIG. . This method has an advantage that the accuracy is good and the insertion time of the thermocouple 4 is short because the cooling water cannot penetrate into the hole inside the copper plate 1.

However, since the expensive copper plate 1 continues to process the movable surface, the size of the hole should be as small as possible, and deep and accurate drilling of small holes (for example, drilling a 3 mm diameter hole up to about 400 mm deep). Is also very difficult to realistically. In addition, the strength of the drill is weak, the drill often breaks while drilling, and it is practically impossible to remove the broken drill from the copper plate. In addition, since the copper plate 1 tends to be thin in recent years, there is a problem in that an area for drilling holes in the copper plate is limited. In the continuous casting, a large amount of water is used to clean the mold after casting. If this water soaks, there is a problem of lowering the accuracy of the measurement temperature as described above. In addition, since the stainless coated thermocouple 4 must be used, there is also a problem in that the sensitivity is lowered compared to the tension bolt 5 method.

The present invention is to solve the conventional problems as described above, its purpose is to accurately measure the temperature by preventing the coolant from seeping into the thermocouple, the continuous casting is made of a very short time to insert the thermocouple while high sensitivity of the temperature change It is to provide a thermocouple for measuring copper plate temperature of a mold.

1 is a cross-sectional view equipped with a thermocouple for measuring copper plate temperature of a continuous casting mold according to the prior art.

2 is a block diagram of a thermocouple for continuous casting copper plate temperature measurement according to the present invention.

3 is a cross-sectional view of the thermocouple for measuring the copper plate temperature of the continuous casting mold according to the present invention.

4 is a configuration in which a thermocouple for measuring the copper plate temperature of the continuous casting mold is mounted.

5 is a cross-sectional view showing the configuration of a general mold.

* Explanation of symbols for main parts of the drawings

1: copper plate 2: coolant

3: water cooling jacket 4: thermocouple

5: bolt 11: Cu ring

11a: cone surface 12: filling material

13: constantan wire 14: coating material

15: Cu lead wire

In order to achieve the above object, the present invention, in the thermocouple for measuring the copper plate temperature of the continuous casting mold, having a conical outer circumferential surface, a hollow space is formed therein, Cu leads drawn out on one side A Cu ring member to form a + electrode; The star is inserted into the hole of the Cu ring member to be welded to form a thermocouple, and the outer surface of the hole is drawn by applying a coating material of insulating material to the outer circumferential surface. A constantan wire forming an electrode; A filler filling the hole to insulate the Cu ring member and the constantan wire while insulated; And a bolt mounted on the mold having a hollow hole in which the Cu ring member, the constantan wire, and the filler are embedded. The thermocouple for measuring copper plate temperature of a continuous casting mold is provided.

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

The basic principle of the thermocouple 10 for measuring copper plate temperature of the continuous casting mold according to the present invention is a T-type (Copper-Constantan), and the Cu ring 11 processed to be inclined like the second degree is a (+) pole, (− The pole constantan wire 13 is welded inside the Cu ring 11 to form a thermocouple. Between the Cu ring 11 and the constantan line 13 is filled with a filler 12 that can withstand the temperature of the copper plate 1 to be insulated from each other. The filler 12 used here is a material that has an insulating action such as Teflon and silicon and is flexible and can withstand high temperatures. Cu wire 15 is welded to the Cu ring 11 and drawn out. The constantan wire 13 outside the Cu ring 11 is coated with the coating material 14 and also drawn out. The covering 14 may use a cable material having a heat shrinkage action.

Hereinafter, the operation of the thermocouple 10 of the present invention will be described.

Although the thermocouple 4 coated with the conventional stainless steel has a low thermal conductivity, the temperature cannot be sensitively measured, but the Cu ring 11 of the thermocouple 10 of the present invention becomes a (+) pole of a T-type thermocouple and has thermal conductivity. It is high, and the temperature of the copper plate 1 can be measured sensitively. In addition, since the surface of the copper plate 1 does not need to be drilled, the time required for inserting the thermocouple 10 is shortened, and there is no reduction in the life of the copper plate 1. In addition, since the inside of the Cu ring 11 and the constantan wire 13 are insulated with elastic resin, the inside of the Cu ring 11 and the constantan wire 13 are insulated with a flexible resin. Since the furnace cannot penetrate at all, the life of the thermocouple 10 is increased and accurate measurement is ensured.

On the other hand, since the tip distance between the copper plate (1) heating surface and the tension bolt (5) is different in the mold longitudinal direction, the copper plate temperature at the same distance from the heating surface can be measured by the tension bolt method. There was no problem, but the thermocouple 10 of the present invention can solve the problem by changing the thickness of the Cu ring 11 of the thermocouple 10 inserted in the mold longitudinal direction. Since copper copper is used as the Cu ring 11 material, the thermocouples specified in the standard are configured to ensure accurate temperature measurement.

In order to analyze the heat, stress, flow and solidification behavior of molten steel and cast steel in casting molds, it is necessary to measure the heat flux at the local position, which measures the temperature at different distances in the heat transfer direction. It is a common way to ask. However, it is impossible to measure the heat flux because two thermocouples cannot be inserted in the same thickness direction by the conventional tension bolt method, and the temperature is measured at different distances from the heating surface by the above-described thermocouple vertical insertion method. It was obtained. However, this method also requires the insertion of the thermocouple 4 at a considerable distance since the holes for inserting the thermocouple 4 are located adjacent to each other in addition to the difficulty of machining and the decrease in the life of the copper plate. As a result, the dynamic behavior of cast and molten steel in molds has the inherent problems of large scattering and inaccurate local thermal fluxes. However, the thermocouple 10 of the present invention can measure the heat flux accurately and very easily by processing the inner thickness of one Cu ring 11 in layers and welding two strands of constantan wire 13 and Cu wire 15. can do.

In the actual mold, the thermocouple 10 of the present invention is inserted by the tension bolt method. 3 is a schematic diagram illustrating the insertion of the thermocouple 10 of the present invention. As for the tension bolt 5 used in the present invention, the hole tip 5a of the tension bolt 5 catching the copper plate name is the conical surface 11a of the Cu ring 11. Processed at the same slope as the end of the tension bolt in contact with the copper plate (1) surface is characterized in that the rounded. That is, when the thermocouple 10 (FIG. 2) of the present invention is inserted into the tension bolt 5 and the bolts are tightened, the inclined hole tip 5a surface is pressed against the relatively soft Cu ring 11, and moisture is released. It will not be able to penetrate at all. In addition, since the rounded end of the bolt presses the copper plate 1 surface so that no moisture can penetrate outside the Cu ring 11, the thermocouple 10 and the tension bolt 5 of the present invention are used in the mold. The insertion of the thermocouple 10 is completed automatically in the usual way of assembling the copper plate. EXAMPLE

12 thermocouples 10 including the present invention in four molds were inserted and the effects of the present invention were examined by the items shown in Table 1 while continuously measuring the temperature of the copper plate 1.

The vertical insertion method is used for the precise work of drilling holes in the copper plate, and the conventional tension bolt method using the constantan welding thermocouple (4) takes a lot of time for the welding operation. As a result of the water pressure test at 10 atm after tightening the tension bolt (5), moisture was infiltrated into the thermocouple (4), which is half of the conventional tension bolt method. And it can be seen that there is a problem that takes a long time to remove the thermocouple (4) in which moisture is penetrated and completely remove the water of the water cooling jacket (3) and reinsert the thermocouple (4). In both the conventional tension bolt method and the vertical insertion method, since water can penetrate from the outside, pipe processing, sealing material application and drying for sealing the outside are also time-consuming. However, the stainless steel sheathed thermocouple 4 inserted through such a difficult process had a very low thermal conductivity, resulting in extremely low breakout edge reliability.

In addition, when the mold was used up to 500 times, moisture penetrated a considerable number of thermocouples 4, and thus the copper plate temperature could not be measured accurately. However, it can be seen that the thermocouple 10 of the present invention is simple in handling and very high in reliability.

As described above, according to the present invention, an improved effect is obtained by accurately measuring the temperature by preventing the cooling water from infiltrating into the thermocouple and making the thermocouple insertion time very short while the sensitivity of the temperature change is high.

Claims (2)

In the thermocouple for measuring the copper plate temperature of the continuous casting mold, it has a conical outer peripheral surface (11a), a hollow space is formed inside, the Cu lead wire 15 is drawn to one side to form a + electrode Cu ring member 11; A tip is inserted into the hole of the Cu ring member 11 to be welded to form a thermocouple, and the outside of the hole is coated with a coating material 14 of an insulating material on the outer circumferential surface thereof, and is drawn out. 13); A filler (12) filling the hole to insulate and seal between the Cu ring member (11) and the constantan wire (13); And a bolt (5) mounted on the mold with a hollow hole in which the Cu ring member (11), the constantane wire (13), and the filler material (12) are embedded. Thermocouple for measuring copper plate temperature. The inner end surface 5a of the bolt 5 in contact with the conical outer circumferential surface 11a of the Cu ring member 11 has the same curvature as the conical outer circumferential surface 11a of the Cu ring member 11. A thermocouple for measuring copper plate temperature of a continuous casting mold, characterized by forming a conical surface and forming a sealing structure.