JP2845706B2 - Molding equipment for continuous casting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is to continuously cast a slab having a complicated cross-sectional shape such as a beam blank (mold steel material) or a near net shape (I-shaped steel or H-shaped steel having a cross-sectional shape closer to a product) from a mold. The present invention relates to a molding device for a continuous casting facility.

[0002]

2. Description of the Related Art It has been known that, in continuous casting using a mold powder, the melting characteristics and viscosity of the powder are closely related to the occurrence of vertical cracks. The vertical crack length is shorter and the maintenance rate is lower than when powder is used. In general, it is known that if the viscosity of the powder is too low, the penetration rate of the powder increases, and excessive melting occurs locally, so that the cooling of the shell tends to be uneven.

[0003] In recent years, in continuous casting, casting in which a slab is drawn out in a cross-sectional shape close to the product has been performed in order to reduce the rolling process of the cast product. For example, in continuous casting in the case of a beam blank of an H-shaped steel material, there is a beam blank or the like in which the thickness of the flange portion is larger than the thickness of the web portion. In this case, the web portion having a smaller thickness is cooled faster than the flange portion and solidifies. In some cases, vertical cracks occur in the web portion.

[0004]

However, in the continuous casting of the beam blank made of the H-shaped steel material, in order to solve the problem, the cooling speed of the web forming portion is made slower than the cooling speed of the flange forming portion. And solidifying the flange as uniformly as possible. (For example,
Then, the temperature of the mold copper plate in the web forming portion becomes higher than the temperature of the mold copper plate in the flange forming portion in the mold, and the mold powder dropped on the molten metal surface has a high temperature and a low viscosity in the web forming portion. As a result, the penetration ratio of the powder increases, and excessive penetration occurs locally, whereby the cooling of the shell tends to be uneven. On the other hand, in the flange forming portion, the viscosity becomes low and the amount of penetration decreases, and the remaining powder flows into the high-temperature web forming portion side, resulting in further increasing the penetration rate in the web forming portion.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and provides a molding apparatus for a continuous casting facility that can prevent uneven distribution of the casting powder penetration amount in a plurality of molding portions having different thicknesses and can prevent deterioration of cast slab properties. The purpose is to do.

[0006]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention relates to a molding apparatus for a continuous casting facility provided with a mold for continuously casting a slab having a cross section composed of a plurality of portions having different thicknesses. In addition, in the vicinity of the connecting portion of each slab forming portion, a weir for preventing inflow of casting powder whose lower portion is immersed in the molten metal is suspended.

[0007]

According to the above construction, the cooling speed is reduced, and as a result, the casting powder introduced into the slab forming section where the temperature of the mold copper plate is high has a low viscosity, the penetration rate increases, and the cooling rate increases. Even if the powder for casting, which has a high viscosity and a small amount of penetration, is poured into the slab forming section with a low copper plate temperature and tries to flow from the molten metal surface of the slab forming section to the high-temperature slab forming section side, the penetration preventing weir is used. Since the inflow is prevented by the body, it is possible to prevent uneven penetration in the cast slab forming portion.

Further, since the flow of the casting powder between the molding parts is extremely small, it is possible to use casting powder of a different material for each slab forming part, and the surface temperature of the mold copper plate of each molding part is reduced. Correspondingly, it becomes possible to use a casting powder capable of adjusting the viscosity of the casting powder to enable uniform penetration.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a molding apparatus for a continuous casting facility according to the present invention will be described below with reference to the drawings.

This embodiment relates to a molding apparatus for continuously casting a slab (near net shape) 3 composed of flange portions 1 and 1 and a web portion 2, and relates to a thickness FT of the web portion 2 with respect to a thickness FT of the flange portion 1. In a molding apparatus of a continuous casting facility provided with a mold 4 for continuously casting a slab 3 having a small diameter, and a cooling rate of the web forming section 12 being made slower than a cooling rate of the flange forming section 11, the flange forming section of the web forming section 12 is provided. In the vicinity of a connection portion with the casting 11, an inflow prevention weir 13 of a casting powder whose lower portion is immersed in the molten metal M is arranged.

That is, the slab 3 has, for example, a height H of 530 mm (product height of 500 mm), a width W of 230 mm (product width of 200 mm), and a thickness FT of the flange portion 1 of 80 mm.
(The thickness of the product flange 1 is 14 to 19 mm), the thickness WT of the web 2 is 50 mmm (the thickness of the product web 2 is 9 to 9 mm).
11 mm).

The mold 4 is composed of four mold divisions 4a and 4b each having a cooling water passage formed therein, and the cooling capacity of the mold 4a on the flange forming portion 11 side is reduced by the mold on the web forming portion 12 side. 4b, the cooling rate of the flange forming section 11 is
It is configured to be faster. The inflow prevention weir 1
3 is supported by a weir support 14 arranged on the mold 4 and the lower part is immersed in the molten metal M. Further, a small gap (about several mm) D is provided between itself and the mold wall surface 4c.

Further, the flange forming portion 1 of the mold 4
1 and the casting powder supplied to the web forming unit 12 are:
A material having an optimum viscosity and an almost constant penetration amount is selected corresponding to the mold copper sheet temperature of the flange forming section 11 and the mold copper sheet temperature of the web forming section 12, respectively. Also, casting powder of the same material can be used.

In the above-described configuration, the molten metal is supplied from a nozzle (not shown) which is suspended at one or both of the flange forming portion 11 and the web forming portion 12, and the molten metal is supplied from the flange forming portion 11 and the web forming portion 12. Casting powder is sprinkled on the surface of the molten metal to start casting.
In this casting powder, the flange forming portion 11 and the web forming portion 12 are separated by the inflow prevention weir 13, so that they do not flow and mix on the surface of the molten metal, and an appropriate amount of the casting powder melts into the casting powder. The surface properties of the piece do not deteriorate. When using the same casting powder,
Although the penetration amount of the web forming part 12 is larger than that of the flange forming part 11, the inflow prevention weir 13 allows the casting powder to be transferred from the flange forming part 11 having a large remaining amount of the casting powder to the web forming part 12 having a small remaining amount. Since the inflow is prevented, it is possible to prevent the difference in the penetration amount from expanding and further deteriorating the slab properties.

According to the above configuration, the inflow prevention weir 13 partitions the slab forming portion of the mold 4 into the pseudo-simple-shaped flange forming portions 11 and 11 and the web forming portion 12 so as to perform uniform penetration. Flange forming part 11, 1
1 to prevent the movement of the casting powder between the web forming unit 12 and enable the use of a dedicated casting powder,
Uniform penetration can be achieved as a whole.

[0016]

As described above, according to the present invention, the casting powder introduced into the slab molding part having a low cooling rate and a high temperature has an increased penetration rate, a high cooling rate and a low temperature. Even if the casting powder that has been injected into the slab forming section and has a small amount of penetration attempts to flow from the molten metal surface of the slab forming section to the high-temperature slab forming section side, the inflow is prevented by the penetration preventing weir body. Therefore, it is possible to prevent uneven penetration in the cast slab.

Also, since the flow of the casting powder between the forming parts is extremely small, it is possible to use a different type of casting powder for each slab forming part. Corresponding and uniform penetration is possible by selecting the casting powder, which can prevent the penetration of the casting powder from increasing in the cast slab where the thickness is small and on the high temperature side. Thus, it is possible to prevent the occurrence of vertical cracks and the like without deteriorating the properties of the slab cast in the slab molding portion of (1).

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a molding apparatus of a continuous casting facility according to the present invention.

FIG. 2 is a cross-sectional view of a slab cast by the molding apparatus.

FIG. 3 is a sectional view taken along line AA shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flange part 2 Web part 3 Cast piece 4 Mold 11 Flange forming part 12 Web forming part 13 Inflow prevention weir 14 Weir support D Clearance

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-262837 (JP, A) JP-A-4-158959 (JP, A) JP-A-2-155545 (JP, A) JP-A-63-1988 20141 (JP, A) JP-A-62-137154 (JP, A) JP-A-62-3852 (JP, A) JP-A-4-210849 (JP, A) (58) Fields investigated (Int. ⁶ , DB name) B22D 11/00 B22D 11/04 311 B22D 11/10

Claims (1)

(57) [Claims] In a molding apparatus of a continuous casting facility provided with a mold for continuously casting a slab having a cross section constituted by a plurality of portions having different thicknesses, a lower portion is located near a connecting portion of each slab forming portion and a lower portion is formed in a molten metal. A molding apparatus for a continuous casting facility, wherein a weir for preventing inflow of casting powder immersed in a pipe is suspended.