JPH01127160A - Roll for continuous casting - Google Patents

Abstract

PURPOSE:To prevent deformation of a roll caused by heat of a cast slab by arranging heat pipes in the roll body supporting the cast slab in continuous casting equipment. CONSTITUTION:Molten metal poured in a tundish 11 is poured into a mold 11 and is cooled with the mold 12 to become the cast slab 13 having non- solidified part in inner part. This cast slab 13 is drawn downward with pinch rolls 16 and also while water cooling with a cooling zone 14, it is supported with guide rolls 15 and sent toward outlet of the continuous casting equipment and perfectly solidified. The guide rolls 15 and the pinch rolls 16 provided plural heat pipes 30 coinciding with the longitudinal direction of the roll body 21 in the inner part of the roll body 21 and embedded along the circumferential direction. Body 31 of the pipe 30 is closed vessel, in which working fluid 32 is charged and wicks 33 are arranged at almost all surface in inner wall of the body 31, and the temp. difference between high temp. part and low temp. part is quickly uniformized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a continuous casting roll that supports continuous casting slabs.

[Prior art] In continuous casting, molten metal in a ladle is continuously supplied into a mold via a tundish, and the molten metal is cooled and solidified by the mold to form a slab, which is then drawn out downward. The material is further cooled with cooling water to completely solidify it, thereby continuously obtaining the desired metal material. When continuous casting is performed in this manner, the slab is pulled out below the mold by rotational driving of the pinch rolls, and the slab cooled in the mold is supported by guide rolls and guided to the exit side of the continuous casting equipment.

[Problems to be solved by the invention] However, the slab has a high degree of m in the center, and
The width of the slab may be narrow, and therefore, the center of the surface of continuous casting rolls such as support rolls and pinch rolls that come into direct contact with the slab becomes hotter than the ends.

As a result, the center portion of the surface of these continuous casting rolls expands significantly, and the distance between the opposing rolls becomes 2 to 3 n+m wider at the center than at the ends. If this happens, the slab will swell in that area due to the deformation of the roll due to the static pressure of the molten steel inside the slab, and at this time, the molten steel will move, making the solidification structure of the slab uneven.
It causes segregation.

Further, since the continuous casting roll is extremely rough only in the portion that is in contact with the slab, there is a risk that the roll may become eccentric after long-term use.

Therefore, when the continuous casting roll deforms as described above,
If this roll has to be replaced, the frequency of roll replacement increases.

This invention was made in view of such circumstances, and
An object of the present invention is to provide a roll for continuous casting in which deformation of slabs due to heat is less likely to occur.

[Means for Solving the Problems] The continuous casting roll according to the present invention is a continuous casting roll that supports slabs in continuous casting equipment, and includes a roll body and a roller provided within the roll body. It is characterized by having a heat pipe.

[Operation] A heat pipe transfers heat from a high temperature section to a low temperature section using the latent heat of vaporization of the working fluid.

In this heat pipe, a working fluid with relatively large latent heat is charged into a closed container, and when a part of the fluid is brought into contact with a high-temperature part and another part with a low-temperature part, the working fluid evaporates in the high-temperature part. This gas is then supplied to the low-temperature section and cooled by the internal pressure difference. At this time, heat is transported from the high temperature area to the low temperature area using the latent heat of vaporization, so it is possible to transport the heat of the sun from the high temperature area to the low humidity area, and as a result, the high temperature area and the low temperature area are It is possible to equalize the temperature difference between the two parts in a short time. If such a heat pipe is installed inside the continuous casting roll as described above, the heat pipe has the effect of uniformizing the humidity as described above, so the temperature of the part of the continuous casting roll where the heat pipe is installed will be reduced. It can be made uniform. Therefore, deformation of the continuous casting roll can be suppressed.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing a continuous casting roll according to an embodiment of the present invention, and FIG. 2 is a schematic diagram showing continuous casting equipment using this continuous casting roll.

Molten metal is poured into the tundish 11 from a ladle (not shown), and m'/IA in the tundish 11 corresponds to the mold 1.
Injected into 2. The molten metal injected into the mold 12 is cooled by the mold 12 to form a slab 13 having an unsolidified portion inside.
becomes. This slab 13 is drawn downward by a vinyl roll 16, is water-cooled in a cooling section 14, is supported by a guide roll 15, and is fed toward the exit of the continuous casting equipment. The slab 13 is completely solidified before reaching the outlet of the continuous casting equipment.

As shown in FIG.
Inside, a plurality of heat pipes 30 are provided whose longitudinal direction coincides with that of the main body 21 and which are embedded along the circumferential direction thereof. The function of the heat pipe 30, which will be described later, prevents the roll body 21 from deforming due to the heat of the slab 13.

Hereinafter, the heat pipe will be explained in detail.

FIG. 3 is a conceptual diagram of a heat pipe. The heat pipe body 31 is a sealed container, and the working fluid 3 is contained in the heat pipe body 31.
2 is loaded. As the working fluid 32, for example, those having a large latent heat of vaporization such as nitrogen, water, and silver are used. In addition, nitrogen is -200 to -160℃, water is 30℃
The temperature for silver is applied in the range of 1800 to 2300'C, respectively. A wick 33 is provided on the inner wall of the main body 31 over substantially the entire surface. The wick 33 is made of copper or stainless wire mesh, or a material having a small capillary diameter such as a sintered body.

When such a heat pipe is installed in a position where a high temperature section 41 having a relatively high temperature and a low temperature section 42 having a relatively low temperature exist, the temperature of the heat pipe main body 31 can be reduced by appropriately selecting the working fluid 32. In the region 34 on the wet part 41 side, the working fluid 32 is heated by the heat of the high temperature part 41 and evaporates to become a gas. Then, the region 35 of the heat pipe main body 31 on the low temperature section 42 side becomes in a relatively low pressure state, and the gaseous working fluid 32 is supplied to the region 35. Since the region 35 is located in the low-temperature section 42, the supplied gaseous working fluid 32 is cooled (that is, radiates heat), condenses, and liquefies. The liquefied working fluid 32 is transported to the region 34 via the wick 33 by the hair mw phenomenon. In this way, the heat from the high temperature section 41 can be transported to the low temperature section 42, and the temperature difference therebetween can be alleviated.

In this case, since heat can be transported using the latent heat of vaporization, a relatively large amount of heat can be transported from the high temperature part to the low temperature part in a short time. In addition, since heat is transferred by thermal diffusion caused by the steam flow, the temperature difference between the high temperature section and the low temperature section can be quickly equalized.

FIG. 4 is a graph comparing a copper hollow pipe and a heat vibrator and showing the surface humidity of each part when one end of each vibrator is heated and the other end is cooled. In the figure, the solid line indicates the case of a heat vibrator, and the broken line indicates the case of a copper pipe. According to this, it can be seen that in the case of copper pipes, the temperature difference between the heating section and the cooling section is about 80 degrees Celsius, while in the case of heat vibrators, the temperature difference between them is about 10 degrees Celsius. . This result confirmed the temperature uniformity effect of the heat vibrator.

Since the heat vibrator has the functions explained above,
Even if the temperature of the part of the roll body 21 in contact with the central part of the slab 13 rises, by embedding the heat vibrator 30 inside the roll body 21 as described above, the heat in the central part of the roll body 21 can be quickly transferred to the ends. can be transported to the department.

Therefore, the temperature of the roll body 21 can be made approximately uniform over the longitudinal direction, and deformation of the roll body 21 due to local thermal expansion can be prevented.

When the continuous casting roll manufactured in this way was actually applied to continuous casting equipment and operated, no troubles due to roll deformation occurred. Furthermore, the roll life was conventionally about 1.5 years, but this can be extended to about 3 years.

In this example, a plurality of heat vibrators were buried in the roll body with their longitudinal directions aligned with the longitudinal direction of the roll body, but a plurality of annular heat vibrators were buried along the longitudinal direction of the roll body. You can also do that. In this case, the temperature of the roll body can be made uniform over the circumferential direction.

Moreover, one cylindrical heat vibrator can also be buried throughout the roll body. In this case, the temperature of the roll body can be made uniform throughout.

[Effects of the Invention] According to the present invention, since the heat vibrator is provided within the roll body of the continuous casting roll, the temperature of the portion of the roll body where the heat vibrator is embedded can be made uniform. For this reason,
It is possible to prevent operational troubles due to roll deformation,
Roll life can be extended.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing a continuous casting roll according to an embodiment of the present invention, Fig. 2 is a schematic diagram showing continuous casting equipment, Fig. 3 is a conceptual diagram showing a heat vibrator, and Fig. 4 is a schematic diagram showing a heat vibrator. It is a graph diagram showing the effect of. 13: Slab, 15; Guide roll, 16: Vinci roll, 21: Roll body, 30; Heat vibrator, 31; Heat pipe body, 32: Working fluid, 33; Wick applicant patent attorney Takehiko Suzue

Claims (1)

[Claims] 1. A continuous casting roll that supports slabs in continuous casting equipment, the continuous casting roll comprising a roll body and a heat pipe provided within the roll body.