KR870001848B1 - Method for crack observation of solidification shell to continuous casting - Google Patents

Abstract

Breadage of the shell of castings produced by a horizontal continuous casting machine is monitored by displacement meters or distortion gauges outside the mold, which can therefore have a simple construction. A mold with an outer sleeve defining a cooling water space is fed from a tundish via a feed nozzle. A clamp plate around the feed nozzle is held to a flange of the mold outer sleeve by clamp rods. Distortion gauges are mounted on these rods and a sharp change in distortion gauge output is taken to be caused by casting shell breakage. Alternatively, monitoring is done using the output of micro-displacement meters mounted in the mold outer sleeve with sensors contacting the mold outer wall.

Description

Method for monitoring breakage of solidification cell of metal slab generated when drawing metal slab from horizontal continuous casting machine

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic explanatory cross sectional view showing an example of a coupling portion between a Turdish and a mold in a conventional horizontal continuous casting machine;

FIG. 2 shows an example of a conventional cycle consisting of extracting and pushing back out of the mold intermittently and continuously in the horizontal direction.

FIG. 3 (a) is an explanatory diagram showing the state of formation of the solidification cell of the slab during the extraction cycle in one cycle consisting of extracting and retracting the metal slab intermittently and continuously in the horizontal direction from the mold; .

FIG. 3 (b) is an explanatory diagram showing the state of formation of the solidification cell of the slab when one cycle consisting of extraction and retraction for intermittently and continuously withdrawing the metal slab from the mold in the horizontal direction is completed.

FIG. 3 (c) is an explanatory diagram showing the breaking state of the solidification cell of the metal cast.

4 is a schematic cross-sectional view showing one embodiment of the method of the present invention.

5 shows the relationship between the breakage of the solidification cell of a metal slab and the deformation value of the mold measured according to the method of the invention shown in FIG. 4 and the temperature value of the mold measured according to the prior art. graph.

6 is a schematic cross-sectional view showing another embodiment of the method of the present invention.

7 shows the relationship between the breakage of the solidification cell of the metal slab and the strain value of the fastening rod measured according to the method of the present invention shown in FIG. 6 and the temperature difference of the mold measured according to the prior art. Graph.

* Explanation of symbols for main parts of the drawings

1: Toondishi 2: Mould

3: feed nozzle 4: brake ring

5: fastening rod 6: spring

7 Nut 8 Clamp Plate

9: coat 11: micro displacement measuring instrument

12: space 11: measurer

13: sleeve 14: transducer

The present invention relates to a method for monitoring the breakage of the solidification cell of the metal slab in the mold that occurs when the metal slab is intermittently and continuously drawn out from the mold of a horizontal continuous casting machine. Nowadays, a horizontal continuous casting method of metal slabs, which is adapted to intermittently and continuously extract the slabs of the metal in a horizontal direction, from a mold arranged horizontally in an opening under the sidewall of a turbid dish containing molten metal.

1 is a schematic cross-sectional view showing an example of a coupling portion between a Turdish and a mold in a conventional horizontal continuous casting machine. In FIG. 1, reference numeral 1 denotes a mold with a coat 9 arranged horizontally in the opening 1a below the side wall of the turbine 24 for accommodating molten metal. Between the mold 2 and the coat 9, a space 12 through which the coolant for cooling the mold 2 circulates is formed.

In FIG. 1, reference numeral 3 denotes a feed nozzle horizontally mounted in the opening 1a of the lower side wall of the turbidish 1, and 4 denotes a gap between one end of the feed nozzle 3 and the inlet of the mold 2; Brake ring mounted horizontally on the The outer circumference of the end portion at which the brake ring 4 of the feed nozzle 3 is in contact has an inclined surface that extends outward. The outer circumference of the end contacting the mold 2 of the brake ring 4 has an inclined surface facing inward. The brake ring 4 fits into the inlet of the mold 2 having an inclined surface that coincides with the inclined surface of the brake ring 4.

In Fig. 1, reference numeral 8 denotes an annular clamp plate having an inner hole coinciding with the inclined surface of the feed nozzle 3 at the center thereof, and the inclined surface of the feed nozzle 3 is engaged in the inner hole. The mold 2 has a flange 2b at its inlet, and the coat 9 also has a flange 9a. Then, the flange 9a of the coat 9 is fixed to the flange 2b of the mold 2.

The flange 9a of the coat 9 has a plurality of fastening rods 5 and nuts 7 passing through the clamp plate 8 and a plurality of through holes provided along the outer periphery of the flange 9a of the coat 9. By the clamp plate 8, the spring 6 is attached to one end of each of the fastening rods 5, respectively.

Thus, by tightening the nut 7, the coat 9, mold 2, brake ring 4 and feed nozzle 3 have one volume via a plurality of sets of fastening rods 5 and a plurality of springs 6. It is also elastically combined. In addition, a hydraulic cylinder may be used instead of the spring 6 described above.

The metal casting is cast as follows by the horizontal continuous casting machine. In other words, the molten metal contained in the turbidish (1) in the mold (2) through a plurality of cycles consisting of extracting and pushing back in the mold (2) horizontally installed in the lower part of the turbidish (1) And, from the mold 2, intermittently and continuously in the horizontal direction while forming the solidification cell. Thus, the metal cast is continuously cast.

2 is an explanatory diagram showing an example of a cycle composed of the extraction and pushing out of the above-described metal slab. In FIG. 3, the abscissa represents time, and the ordinate represents the extraction speed of the slab at its zero point and the compressive force exerted on the slab by pushing back the slab at its zero point.

3 (a) and 3 (b) show the solidification cells of the cast slab in the mold 2 when the metal cast is intermittently and continuously taken out horizontally from the mold 2 in the manner described above. As explanatory drawing which shows the formation state, FIG. 3 (b) shows the formation state of the solidification cell of the cast steel in the extraction degree in 1 cycle comprised of extraction and repulsion, and FIG. 3 (b) is extraction and Fig. 3 (b) shows the solidification cell formed during the extraction cycle in one cycle composed of push-back, and Fig. 3 (b) shows the solidification cell of the cast slab when one cycle composed of extraction and push-back is completed. Shows the formal state of. The molten metal that flows into the mold 2 from the turbid dish 1 containing the molten metal is cooled by the mold 2 and the brake ring 4 to be shown in FIGS. 3 (a) and 3 (b). Similarly, the solidification cell 10 is formed, and the solidification cell 10 is cooled by the mold 2 to be intermittently and continuously extracted from the mold 2 in the horizontal direction while increasing its thickness.

However, in some cases, the coagulation cell 10 breaks when the coagulation cell 10 extracts the next cycle. 3 (c) is an explanatory diagram showing a breaking state of the coagulation cell 10. As shown in FIG. 3 (c), if the coagulation cell 10 continues to be extracted from the mold 2 of the cast steel while the solidification cell 10 is broken in the mold 2, a breakout occurs at the outlet of the mold 2 This will cause serious accidents and at the same time make subsequent casting impossible.

In order to prevent such a problem, when the solidification cell 10 is broken in the mold 2, the extraction of the cast steel from the mold 2 is temporarily stopped and the molten metal flowing into the fracture part is cooled and solidified. The fracture should be welded. Therefore, it is necessary to monitor the breakage of the coagulation cell 10 formed in the mold 2 during the extraction of the cast steel from the mold 2. In order to prevent breakout of cast steel, the following method is known as a method of monitoring the breakage of the coagulation cell in a mold.

The method as described in Japanese Patent Publication No. 26,812 / 74 of July 12, 1974.

In a plurality of cycles, each of which consists of extracting and pushing back from a mold mounted horizontally by a plurality of fastening rods through a brake ring in a feed nozzle mounted horizontally in an opening of a lower side wall of a turbid dish containing molten metal. By intermittently and continuously extracting the slab of the metal by the horizontal direction, the temperature of the mold is continuously measured by a thermocouple embedded in the wall of the mold near which the solidification cell is first formed. When the stored temperature drops sharply, the coagulation cell of the cast steel breaks in the mold and the break in the mold of the coagulation cell of the cast steel is monitored (hereinafter referred to as "prior art").

The reason why the breakage of the coagulation cell in the mold can be detected by the temperature of the mold in the above-described prior art is explained next. That is, as shown in FIG. 3 (c), when the coagulation cell 10 breaks in the mold 2, the mold 2 which participates in the coagulation cell 10 remaining on the brake ring 4 side is removed. The portion of the portion is hindered by the remaining coagulation cell 10 in direct contact with the molten metal of high temperature in the mold (2), so that the temperature drops sharply. Therefore, if the thermocouple is embedded in the wall of the mold 2 in the vicinity where the solidification cell 10 is first formed, and the temperature of the portion of the mold 2 is continuously measured by the thermocouple, the breakage of the solidification cell 10 can be monitored. Can be.

However, the above prior art needs to embed a thermocouple in the wall of the mold for the measurement of the mold temperature. Therefore, it is necessary to provide a hole for embedding the thermocouple in the wall of the mold and a passage through which the conductor is connected to the thermocouple. As a result, the shape of the mold becomes complicated, so that the mold is easily deformed, and the manufacturing cost of the mold rises. In addition, the work of attaching the thermocouple to the mold is complicated, and a great deal of effort is required for the mounting of the thermocouple and the mold replacement.

Accordingly, an object of the present invention is to provide a special processing to a mold for breaking the solidification cell of the metal slab in the mold, which occurs when the metal slabs are intermittently and continuously extracted from the mold of the horizontal continuous casting machine in the horizontal direction. It is to provide a simple, economical and highly accurate method of monitoring without work.

Provided is a method for monitoring breakage of a solidification cell of a metal slab generated when a metal slab is extracted from a horizontal continuous casting machine configured as one of features of the present invention.

Consists of extracting and pushing back from the mold having the outer surface horizontally mounted by a plurality of fastening rods through a brake ring through a feed nozzle mounted horizontally in the opening of the lower side wall of the turbid dish containing molten metal. As the following method for monitoring the break in the mold of the solidification cell of the slab, which occurs when the slab of the metal is intermittently and continuously taken out in a horizontal direction by a plurality of cycles.

While extracting the cast from the mold by the plurality of cycles, the temperature of the mold was continuously measured, and when the measured temperature dropped sharply, the solidification cell of the cast was broken in the mold. The breaking in the mold of the coagulation cell of the cast is monitored.

Method characterized by the following.

Continuously measuring strain value of the mold while extracting the cast from the mold by the plurality of cycles; And the measured strain value is used as the watering of the temperature value of the mold, and when the measured strain value of the mold is suddenly changed, the solidification cell of the cast steel is broken in the mold as the solidification cell of the cast steel. The break in the mold is monitored.

From the above point of view, we do not apply the mold to the mold for breaking of the solidification cell of the cast in the mold, which occurs when the metal cast is intermittently and continuously taken out horizontally from the mold of the horizontal continuous casting machine. Efforts have been made to develop a simple, economical and highly accurate method of monitoring.

As a result, we extract and push back from the mold with the outer surface horizontally mounted by a plurality of fastening rods via brake rings in a feed nozzle mounted horizontally in the opening of the lower sidewall of the Turdon dish containing molten metal. The deformation value of the mold during the intermittent and continuous extraction of the slab of the metal in the horizontal direction by a plurality of cycles consisting of a bet is closely related to the temperature value of the mold during the extraction of the slab. In fact, it has been found that the deformation values of the plurality of fastening rods are closely related to the deformation values of the mold.

The present invention has been studied in accordance with the above-described aspects. Hereinafter, a method for monitoring breakage of the solidification cell of the metal slab generated when the metal slab is extracted from the horizontal continuous casting machine according to the present invention will be described. .

4 is a schematic cross-sectional view showing one embodiment of the method of the present invention (hereinafter referred to as "first embodiment"). In FIG. 4, reference numeral 2 denotes a mold 4 having a coat 9 mounted horizontally in an opening under the side wall of a Turdish (not shown) for accommodating molten metal into the inlet of the mold 2. Brake ring.

The mold 2, the coat 9, the brake ring 4 and the feed nozzle (not shown) are integrally and elastically coupled by a plurality of fastening rods (not shown).

The outer surface 2a of the mold 2 is wrapped in a coat 9, and a space 12 is formed between the mold 2 and the coat 9 in which the coolant for cooling the mold 2 circulates.

In FIG. 4, (11) is at least 1 micro displacement measuring system which measures the deformation value of the mold 2. As shown in FIG.

At least one microdisplacement measuring instrument 11 is mounted to the coat 9 and the measurer 11a of the at least one microdisplacement measuring instrument 11 penetrates the coat 9 so that its tip is outside the mold 2. It is in contact with the surface 2a.

As apparent from FIGS. 3 (a) and 3 (b), the thickness of the coagulation cell 10 formed in the mold 2 is thinner at the inlet side than the outlet side of the mold 2, and thus the third (c). As is apparent from the figure, 5 of the distance (usually about 5mm-50mm) at which the cast is extracted by one cycle consisting of extraction and pushing back near the entrance of the mold 2, in particular, at the entrance of the mold 2 The breakage of the coagulation cell 10 is likely to occur within the range of less than twice the distance. Therefore, the position at which the measuring member 11a of the at least one microdisplacement measuring system 11 is in contact with the outer surface 2a of the mold 2 is one cycle composed of extraction and pushing back from the inlet of the mold 2. It is necessary to be within the range of 5 times or less of the distance from which the cast is extracted. Moreover, the contact position with respect to the outer surface of the mold 2 of the said measuring member 11a is less than twice the distance which a cast is extracted by one cycle consisting of extracting and pushing back at the entrance of the mold 2. It is suitable to increase the measurement accuracy in the range of the distance.

In the first embodiment shown in FIG. 4, the breakage of the solidification cell of the metal slab is monitored by the above-described at least microdisplacement measuring system 11 as follows. That is, during the extraction of the metal slab from the mold 2 by a plurality of cycles consisting of extracting and pushing back, respectively, the measurement of the mold 2 by the measuring member 11a of the at least one microdisplacement measuring system 11 described above. The strain value is measured continuously, and the measured strain value is used as the watering of the temperature value of the mold 2 and the solidification cell of the cast is monitored as broken in the mold 2 when the measured strain value changes abruptly.

In the first embodiment shown in FIG. 4, the reason why the deformation value measured by the mold 2 can be used as the watering of the temperature of the mold 2 is as follows. In other words, if a fracture occurs in the solidification cell of the metal slab in the mold (2), the mold (2) shrinks rapidly because the temperature of the mold (2) drops sharply as described above. In addition, there is an extremely close relationship between the breakage of the solidification cell of the cast steel, the sharp drop in the temperature of the mold 2, and the sharp shrinkage of the mold 2, as shown in FIG. Therefore, by continuously measuring the strain value of the mold 2, it is possible to monitor the breakage of the solidification cell of the metal slab.

5 shows the relationship between the fracture of the solidification cell of the metal slab and the deformation value of the mold measured according to the first embodiment of the method of the invention shown in FIG. 4 and the temperature value of the mold measured according to the prior art. It is a graph. As shown in FIG. 5, the measured temperature and strain values of the mold 2 during the stable extraction of the metal cast from the mold 2 by a plurality of cycles consisting of extracting and pushing back, respectively, Match and fluctuate proportionally within a certain range. On the other hand, when the coagulation cell of the cast steel breaks in the mold 2, the measured temperature value of the mold 2 is drastically dropped, and the measured strain value of the mold 2 is drastically changed in accordance with the sudden drop of the temperature value.

Therefore, if the strain value of the mold 2 is continuously measured while extracting the rapid cast from the mold 2 by a plurality of cycles consisting of extracting and pushing back, the measured strain value of the mold 2 changes rapidly. When the coagulation cell of the cast steel breaks in the mold 2, the breakage in the mold 2 of the coagulation cell of the cast steel can be monitored. As a result of analyzing the heat transfer and thermal stress from the molten metal of the mold 2 during the extraction of the metal slab, the variation of the deformation value of the mold 2 during the extraction of the cast slab was obtained in the normal extraction state. The case was about 10 micrometers. Therefore, at least the microdisplacement measuring system 11 for measuring the deformation value of the mold 2 can use a differential transformer type displacement meter, an eddy current range meter, or the like which is generally sold.

In the case where the shape of the mold 2 is quadrangular, the microdisplacement measuring system 11 may be attached to at least one side of the coat 9 or at least one co-owner, and the shape of the mold 2. If this cross section is circular, at least one may be mounted on the circumference. When a plurality of micro displacement measuring systems 11 are mounted, the breakage of the solidification cell of the metal slab is monitored as described above by the average value of the measured values by each micro displacement measuring system 11.

Next, another embodiment of the method of the present invention (hereinafter referred to as "second embodiment") will be described. 6 is a schematic cross-sectional view showing a second embodiment of the method of the present invention. In FIG. 6, reference numeral 2 denotes a mold having a coat 9 mounted horizontally in an opening under the side wall of a Tidian dish (not shown) for accommodating molten metal. Between the mold 2 and the coat 9, a space 12 through which the coolant for cooling the mold 2 circulates is formed.

In Fig. 6, reference numeral 3 denotes a feed nozzle horizontally installed in the opening of the lower side wall of Turundish (not shown), and 4 denotes a gap between the first end of the feed nozzle 3 and the inlet of the mold 2; Brake ring mounted horizontally. The outer circumference of the end portion at which the brake ring 4 of the feed nozzle 3 contacts is inclined toward the outside. The outer circumference of the end contacting the mold 2 of the brake ring 4 has an inclined surface facing inward. The brake ring 4 is fitted to the inlet of the mold 2 having an inclined surface that coincides with the slope of the brake ring.

In FIG. 6, reference numeral 8 denotes an annular clamp plate having an inner hole coinciding with the slope of the feed nozzle 3 at the center thereof, and the inclined surface of the freind nozzle 3 engages in the inner hole. The mold 2 has a flange 2b at its inlet, and the coat 9 also has a flange 9a. And the flange 9a of the coat 9 is fixed to the flange 2b of the mold 2. The flange 9a of the coat 9 has a plurality of sets of fastening rods 5 and nuts 7 passing through the clamp plate 8 and a plurality of through holes provided along the outer periphery of the flange 9a of the coat 9. It is attached to the clamp plate 8 by this, and the spring 6 is attached to each end of each of the fastening rods 5.

Thus, by tightening the nut 7, the coat 9, mold 2, brake ring 4, and feed nozzle 3 have one volume via a plurality of sets of fastening rods 5 and a plurality of springs 6. It is also elastically combined.

In FIG. 6, reference numeral 14 denotes at least one strain gauge for measuring at least one strain value of the plurality of fastening rods 5. At least one strain gauge 14 is mounted on the surface of the at least one fastening rod 5 between the clamp plate 8 and the flange 9a of the envelope 9.

In the second embodiment shown in FIG. 6, the breakage of the solidification cell of the metal slab is monitored by at least one strain gauge 14 as follows. That is, the strain values of the at least one fastening rod 5 are continuously measured by the at least one strain gauge 14 while extracting from the metal slab mold 2 by a plurality of cycles each consisting of extracting and pushing back. And the measured strain value is used as the watering of the strain value of the mold 2, and when the measured strain value of the at least one fastening rod 5 changes abruptly, the solidification cell of the cast piece breaks in the mold 2; Monitor as one.

The reason why the measured strain value of at least one fastening rod 5 can be used as the function of the strain value of the mold 2 in the second embodiment shown in FIG. 6 is as follows. In other words, when a fracture occurs in the solidification cell of the metal slab in the mold 2, the temperature of the mold 2 drops sharply as described above, so that the mold 2 contracts rapidly. This contraction occurs not only in the longitudinal direction of the mold 2 but also in the radial direction of the mold 2.

As shown in FIG. 6, the inlet portion of the mold 2 has a tapered surface coinciding with the tapered surface of the brake ring 4, so that when the mold 2 contracts in the radial direction as described above, the brake ring (4), the feed nozzle (3) and the clamp plate (8) are moved toward the Turdish 2 (2).

As a result, the deformation value of the at least one fastening rod 5 changes abruptly. There is a close relationship between the break of the solidification cell of the cast steel and the sudden change of the temperature of the mold 2 and the sudden change of the deformation value of the at least one fastening rod 5 as shown in FIG.

Therefore, it is possible to monitor the occurrence of the breakage of the solidification cell of the metal slab by continuously measuring the change in the deformation value of the at least one fastening rod 5.

7 shows the fracture of the solidification cell of the metal slab and the strain value of at least one fastening rod measured according to the second embodiment of the inventive method shown in FIG. 6 and the temperature value of the mold measured according to the prior art. A graph showing the relationship between

As shown in FIG. 7, the measured temperature value of the mold 2 and at least one fastening while the metal cast is stably extracted from the mold 2 by a plurality of cycles configured to extract and push back, respectively. The measured strain of the rod 5 fluctuates proportionally within a certain range in accordance with the cycle. On the other hand, when the coagulation cell of the cast steel breaks in the mold 2, the measured temperature value of the mold 2 drops rapidly, and coincides with the sudden drop of the temperature value, so that the measured temperature of the at least one fastening rod 5 is measured. The strain value also changes rapidly.

Therefore, while continuously extracting the metal slab from the mold 2 by a plurality of cycles each consisting of extracting and pushing back, continuously measuring the strain of the at least one fastening rod 5 results in at least one fastening rod 5 When the measured strain value of) rapidly changes, the solidification cell of the cast steel breaks in the mold 2, and the breakage in the mold 2 of the solidification cell of the cast steel can be monitored. When a plurality of strain gauges 14 are provided, the breakage of the solidification cell of the metal slab is monitored as described above by the average value of the measured values by the strain gauges 14.

Next, another embodiment of the method of the present invention (hereinafter referred to as "third embodiment") will be described. In a third embodiment of the method of the invention, the sleeve 13 is connected to at least one fastening rod 5 between the flange 9a and the spring 6 of the coat 9 as shown in conjunction with FIG. 6. Is fitted, and at least one strain gauge 14 is mounted on the surface of the sleeve 13. The strain value of the sleeve 13 is measured by the at least one strain gauge 14, and the measured strain value is used as the irrigation of the strain value of the at least one fastening rod 5, and the measured strain value changes rapidly. When monitored, the solidification cell of the metal cast is monitored as broken in the mold (2).

The reason why the measured strain value of the sleeve 13 can be used as the watering of the strain value of the at least one fastening rod 5 in the third embodiment shown in conjunction with FIG. 6 is as follows. That is, when fracture occurs in the solidification shell of the metal slab in the mold 2, the deformation value of the at least one fastening rod 5 changes rapidly as described above, and at the same time the sleeve 13 contracts rapidly. In addition, there is an extremely close relationship between the fracture of the solidified shell of the cast steel and the sudden change of the temperature of the mold 2 and the sudden shrinkage of the sleeve 13 as shown in FIG. Therefore, by continuously measuring the change of the deformation value of the sleeve 13 fitted to the at least one fastening rod 5, it is possible to monitor the occurrence of fracture of the solidification shell of the metal slab.

The temperature of the sleeve 13 fitted to the at least one fastening rod 5 and the at least one fastening rod 5 is increased by the heat of the metal slab in the mold 2, the temperature of which is at most 150 ° C. It is enough. Thus, the at least one strain gauge 14 mounted on the at least one fastening rod 5 or the sleeve 13 may use a commercially available high temperature strain gauge (limit temperature of about 400 ° C.), and at least If one fastening rod 5 or the sleeve 13 is air cooled, a strain gauge for room temperature, which is generally sold, may be used.

The at least one strain gauge 14 for measuring the strain value of the fastening rod 5 may be attached to the at least one fastening rod 5 by appropriate numbers from the diameter and length of the fastening rod 5. At least one strain gauge 14 for measuring the strain value of the sleeve 13 is suitable for the sleeve 13 fitted to the at least one fastening rod 5 in terms of the diameter and length of the sleeve 13, and the like. You just need to install a number.

The deformation occurring in the at least one fastening rod 5 or the sleeve 13 is within the range of the elastic limit of the at least one fastening rod 5 or the sleeve 13. Therefore, the strain generated in the at least one fastening rod 5 or the sleeve 13 by the at least one strain gage 14 mounted on the at least one fastening rod 5 or the sleeve 13 is continuously measured. There is a number. When a plurality of strain gauges 14 are mounted, the breakage of the solidified shell of the metal slab is monitored as described above by the average value of the measured values by the strain gauges 14.

Next, the method of the present invention will be described in detail by way of examples.

Example 1

In the mold of the horizontal continuous casting machine, the fracture of the solidification shell of the cast in the mold occurs when the cross section of 115 mm in the horizontal direction intermittently and continuously extracts a quadrilateral metal cast (usually steel) in the horizontal direction. The deformation value of the mold 2 was continuously monitored according to the first embodiment of the method of the present invention described with reference to FIG.

One differential transformer displacement meter was used as the microdisplacement measuring instrument 11 for measuring the deformation value of the mold 2. The differential transformer type displacement meter is the outer surface of one side of the mold 2 at a position corresponding to twice the distance from which the slab is extracted by one cycle consisting of extraction and retraction from the inlet of the mold 2. It fixed to the outer coat 9 so that the measuring part 11a might contact the center. One thermocouple was embedded in the wall of the mold 2 by the differential transformer displacement meter according to the prior art, and the temperature of the mold 2 was continuously measured by the thermocouple.

As a result, as shown in the graph of FIG. 5, the breakage of the solidification cell of the cast steel in the mold 2 can be reliably monitored by a sudden change in the measured strain value of the mold 2. The rapid change in the measured strain value of the mold 2 due to the breakage of the coagulation cell coincided with the sharp drop in the temperature value of the mold 2 measured by the thermocouple.

When the measured strain value of the mold 2 suddenly changed, the extraction of the metal slab from the mold 2 was stopped and the molten metal introduced into the fracture portion of the solidification cell of the cast was cooled and solidified to weld the fractured portion. . Next, by resuming the extraction of the cast from the mold 2, the casting of the cast from the mold 2 can be performed without generating a breakout.

In this embodiment, the breakage of the solidification cell of the slab in the mold 2 was monitored in the above manner while continuously casting a quantity of 93 molten steel of the ladles with a capacity of 50T ladles. The fracture of the coagulation cell of the said cast was able to be detected to such an extent. Since the differential transformer displacement meter used to measure the deformation value of the mold 2 is fixed to the coat 9 of the mold 2, it is not necessary to replace the differential transformer displacement meter when replacing the mold 2, Also, there was no problem in terms of durability.

Example 2

115 mm of cross-section from the mold of the horizontal continuous casting machine eliminates the breakage of the solidification cell of the cast in the mold, which occurs when the rectangular metal slab (usually steel) is intermittently and continuously extracted in the horizontal direction. According to the second aspect of the method of the present invention described with reference to FIG. 6, the strain value of the at least one fastening rod 5 was monitored by continuously measuring it. One strain gauge 14 for measuring the strain value of the fastening rod 5 was provided on each of the four fastening rods 5 for mounting the flange 9a of the coat 9 to the clamp plate 8. . Each strain value of the four fastening rods 5 was measured continuously with the said strain gauge 14, and the average value was calculated | required. In addition, the four fastening rods 5 were used having a strain sensitivity of 2 × 10 ⁻³ with respect to the load 1T. On the other hand, for comparison, one thermocouple was embedded in the wall of the mold 2 in the vicinity where the solidification cell was first formed, and the temperature of the mold 2 was continuously measured by the thermocouple.

As a result, as shown in the graph of FIG. 7, the breakage of the solidification cell of the cast steel in the mold 2 was monitored in the sudden change in the average value of the measured strain values of the four fastening rods 5. The sudden change in the average value of the measured strain values of the four fastening rods 5 due to the breakage of the solidification cell coincided with the sudden drop in the temperature value of the mold 2 measured by the thermocouple. When the average value of the measured deformation values of the four fastening rods 5 changes abruptly, the extraction of the metal slabs from the mold 2 is temporarily stopped, and the molten metal flowing into the fractured portions of the solidification cell of the slabs is cooled. The fracture was welded by solidification. Next, by resuming the extraction of the cast from the mold 2, it was possible to extract the cast from the mold 2 without a breakout.

In this embodiment, the breakage of the solidification cell of the slab in the mold 2 was monitored in the above-described manner while continuously casting 67 molten steel of the ladle, the capacity of which was contained in a 50T ladle, but was extremely high. The fracture of the coagulation cell of the said cast was able to be detected to such an extent.

Example 3

Breakage of the solidification cell of the slab in the mold, which occurs when intermittent and continuous extraction of a five-sided quadrilateral metal slab (usually steel) from the mold of the horizontal continuous casting machine in the horizontal direction intermittently and continuously Is monitored by continuously measuring the strain value of the sleeve 13 fitted to the at least one fastening rod 5 according to the third embodiment of the method of the present invention described with reference to FIG.

The strain gauge 14 for measuring the strain value of the sleeve 13 has a coat 9 on one of the four fastening rods 5 for mounting the flange 9a of the coat 9 to the clamp plate 8. One was mounted on the surface of the metal sleeve 13 fitted between the flange 9a of the spring) and the spring 6. The strain value of the sleeve 13 was measured continuously by the said strain gauge 14. On the other hand, by comparison, a thermocouple of one system was embedded in the wall of the mold 2 in the vicinity where the solidification cell was first formed, and the temperature of the mold 2 was continuously measured by the thermocouple.

As a result, the breakage of the solidification edge of the cast in the mold 2 could be monitored in the sudden change of the measured strain value of the sleeve 13 as in the second embodiment. The sudden change in the measured strain value of the sleeve 13 due to the breakage of the solidified side coincided with the sudden drop in the temperature value of the mold 2 measured by the thermocouple.

In this embodiment, the strain gage 14 is mounted on the sleeve 13 fitted to the fastening rod 5, so that the fastening rod 5 can be replaced regardless of the strain gage 14. The measurement sensitivity could be set arbitrarily by changing the thickness, length, and the like of the sleeve 13.

As described in detail above, according to the method of the present invention, the fracture of the solidification cell of the metal slab in the mold occurs when the metal slabs are extracted intermittently and continuously in the horizontal direction from the mold of the horizontal continuous casting machine. There are many industrial useful effects such as simple and economical monitoring of the degree without special processing.

Claims (5)

Horizontally mounted by a plurality of fastening rods 5 via a brake ring 4 to the feed nozzle 3 mounted horizontally in the opening 1a of the lower side wall of the turbid dish 1 containing the molten metal. The solidification cell of the slab which occurs when the slab of the metal is intermittently and continuously taken out in the horizontal direction by a plurality of cycles consisting of extracting and pushing back from the mold 2 having the outer surface 2a, respectively. A method configured as follows for monitoring breakage in the mold of (10), wherein the temperature of the mold (2) is drastically reduced while extracting the cast from the mold (2) by the plurality of cycles. In the method of monitoring the breakage in the mold (2) of the coagulation cell 10 of the cast steel as the coagulation cell (10) of the cast steel is broken in the mold (2) Continuously measuring the strain value of the mold 2 while extracting the slab from the mold 2 by the plurality of cycles, and using the measured strain value as a function of the temperature value of the mold 2 And the mold of the solidification cell 10 of the cast steel as the solidification cell 10 of the cast steel breaks in the mold 2 when the deformation value of the mold 2 is rapidly changed. (2) The method characterized by monitoring the said break in. 5. The distance according to claim 1, wherein the cast is extracted by the one cycle consisting of extracting and pushing back from the inlet of the mold 2 to the outer surface 2a of the mold 2; And measuring the strain value of the mold (2) continuously by contacting the measurer (11a) of at least one microdisplacement measuring system (11) within a range of less than or equal distance. The method according to claim 2, wherein the outer surface (2a) of the mold (2) of the distance from which the cast is extracted by the one cycle consisting of extracting and pushing back at the inlet of the mold (2) And the measuring device (11a) of the at least one microdisplacement measuring device (11) in contact within a range of less than twice the distance. The method according to claim 1, wherein at least one strain gauge 14 is mounted on at least one of the plurality of fastening rods 5 to measure at least one strain value of the plurality of fastening rods 5. When at least one measured strain value of the two fastening rods 5 is used as a function of the strain value of the mold 2, and at least one measured strain value of the plurality of fastening rods 5 changes abruptly Monitoring the break in the mold (2) of the coagulation cell (10) of the slab as the coagulation cell (10) of the slab has broken in the mold (2). 5. The sleeve according to claim 4, wherein the sleeve (13) is fitted to at least one of the plurality of fastening rods (5), and the at least one strain gauge (14) is mounted on the surface of the sleeve (13). Measure the strain value of the sleeve 13, and use the measured strain value of the sleeve 13 as a function of at least one of the strain values of the plurality of fastening rods 5, and In the mold 2 of the solidification cell 10 of the slab as the solidified cell 10 of the slab breaks in the mold 2 when the measured strain value of (13) changes abruptly. A method for monitoring the break in the case.

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