JPH0576394B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement of an in-mold electromagnetic stirring device for multi-strand continuous casting equipment for both slab and bloom use.

(Prior art and its problems) In multi-strand continuous casting equipment for both slab and bloom, as shown in Figure 3a, when the roll length L is set by the slab width S, there are restrictions on this roll length. From bloom B end is slab S width
It is necessary to avoid exceeding WS (Fig. 3b)
Reference) Strand spacing LS is large, bloom B
If the edge exceeds the width of the slab S, it is necessary to reduce the number of strands of Bloom B (see Figure 4) or increase the roll length more than necessary (see Figure 5), resulting in decreased productivity and equipment failure. This is not desirable because it causes an increase in costs.

For this reason, it is desirable to minimize the strand spacing during bloom casting so that even if the number of bloom strands is increased, it will still fit within the slab width.
The strand spacing LS is uniquely determined by the mold spacing, so if an electromagnetic stirring coil is built into the mold to perform in-mold electromagnetic stirring, the strand spacing LS will increase by the amount of the coil, and the strand spacing will decrease. There is naturally a limit to making it as small as possible.

(Objective of the Invention) An object of the present invention is to provide an in-mold electromagnetic stirring equipment that can reduce the strand spacing when performing in-mold electromagnetic stirring in multi-strand continuous casting equipment for both bloom and slab use.

(Structure of the Invention) In order to provide an in-mold electromagnetic stirring device that can reduce the strand spacing compared to the conventional one, the present invention eliminates the partition shell installed between the strands and integrates the iron cores of different strands. This was done in view of the fact that it is a good idea to make the V-phase magnetic flux path continuous over multiple strands S ₁ to _{S o} , and it is advantageous to arrange multiple strands S ₁ with an electromagnetic stirring device in the mold. ~S _o (n is an integer greater than or equal to 2)
In a multi-strand continuous casting equipment equipped with a plurality of strands S 1 to ₁ , an iron core 1 surrounding each strand forming an electromagnetic stirring device for each strand is
At the same time, the V-phase coils VC ₁ to _{VC 2o} arranged in each strand are integrated across the strands S ₁ to _{S o} so that the V-phase magnetic flux path is continuous across the plurality of strands S ₁ to S o. An in-mold electromagnetic stirring device for multi-strand continuous casting equipment, characterized in that the winding direction of the coil is reversed, and preferably an iron core portion disposed between adjacent strands is directed to each strand. It is preferable to wind the V-phase coil VC around the core salient pole portion 11 and to wind the auxiliary coil C around the core body 12.

Hereinafter, the present invention will be explained in detail based on preferred specific examples shown in the accompanying drawings.

(Example) FIG. 1 is a sectional view showing a configuration in which the electromagnetic stirring device according to the present invention is applied to three-strand continuous casting equipment,
The arrow indicates the V-phase magnetic flux path.

In the drawing, each strand S ₁ to _{S o} is constructed by assembling copper plates in a square shape according to the size of the slab, and installing a stainless steel back-up plate on the outside to support the copper plates. An electromagnetic stirring device is provided for each strand _S1 to _S3 , but when the strands are housed in a mold, the U-phase coil, V-phase coil, and iron core that make up the electromagnetic stirring device surround the backup plate. It is arranged like this. In the drawing, the core 1 is integrated within the cover 2 with the partition shell removed, and there are _S1 /S2 and _S2 between each strand.
The iron core is shared in S ₂ /S ₃ , the salient pole part of the iron core is half the length of the conventional one, and the V-phase coil is divided into two, excluding VC ₁ and VC ₆ at both ends, to create coils VC ₂ to ₅ . , the coil winding direction is reversed between the strands S ₁ /S ₂ and S ₂ /S ₃ so that the magnetic flux flows in a continuous path, and the number of turns of the coil wound around the salient pole is halved, and the remaining half of the coil is are wound around the body of the iron core to form auxiliary coils C _{1 to} C ₄ to reduce the coil thickness, while U-phase coils UC _1/2 to UC _5/6 are opposed in parallel to each strand S _{1 to S 3} . Arrange. In addition,
In the above case, the number of turns of the two-split coil VC ₂ to ₅ was approximately half, but if there is enough space between the strands,
The number may be the same as the V-phase coils VC ₁ and VC ₆ at both ends, and in this case, the auxiliary coils C ₁ to _{C 4} can be omitted, but even in that case, the magnetic flux density is different from that of the U-phase due to leakage flux. If the stirring pattern becomes unbalanced (a uniform stirring flow cannot be obtained), the current flowing through the auxiliary coils C ₁ to _{C 4} can be adjusted to maintain balance. It is preferable to set it up.

In the electromagnetic stirring device having the above configuration, looking at the V-phase magnetic flux path, the magnetic flux 1 generated in the coil VC ₂ penetrates the copper plate, passes through the inside of the mold, and reaches the coil VC ₁ . Here, magnetic flux 2 is generated by merging with the magnetic flux generated in coil _VC1 . This magnetic flux 2 is divided into two parts, passes through the iron core installed around the periphery, and reaches the auxiliary coils C ₁ and C ₂ . The magnetic fluxes 2 and 3 on the output side of the auxiliary coils C ₁ and C ₂ are each divided into two, and the coil VC ₂
and reach VC ₃ . The same is true between strands S ₂ and S ₃ , and since the coil winding directions of strands S ₁ /S ₂ and strands S ₂ /S ₃ are opposite,
The magnetic flux will flow in a continuous path.

Note that since the U-phase coil is the same as the conventional magnetic flux path, a description thereof will be omitted.

Above, the case of 3 strands was explained as an example, but in the case of 2 strands or 4 or more strands, by considering the same coil arrangement form,
Similar effects can be obtained.

(Operations and Effects of the Invention) As is clear from the above description, according to the present invention, in order to share the electromagnetic stirring coils of different strands, the partition shell surrounding the strands is removed, the iron core is shared, and each strand Since the winding directions of the coils disposed between adjacent strands are reversed so that the magnetic flux path is continuous, the strand spacing can be reduced compared to the conventional method. Incidentally, when comparing the case where three strands of a conventional split mold are installed so that the mold interval is zero and the case of the three-strand form according to the present invention, as shown in FIGS. 2 a and b, the strands are Since the spacing can be extremely reduced, a multi-strand mold can be accommodated within the width of the slab mold. Therefore, the slab
In continuous casting equipment that also serves as a bloom, there is no need to reduce the number of bloom strands or make rolls longer than necessary to prevent the bloom end from exceeding the slab width, improving productivity and reducing equipment costs. useful for.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the internal structure when the electromagnetic stirring device according to the present invention is applied to a 3-strand continuous casting equipment, and Fig. 2a is a sectional view showing the strand spacing of a conventional split mold in a 3-strand continuous casting equipment. figure,
Figure 2b is a cross-sectional view showing the strand spacing when the present invention is applied, and Figure 3a is a conceptual diagram showing the relationship between the roll length L and the slab width S in a multi-strand continuous casting equipment that serves both slab and bloom. figure,
In Figure 3b, the bloom B end is also the slab S width WS.
Figure 4 is a conceptual diagram showing the number of bloom strands reduced when the strand spacing LS is large and the bloom B end exceeds the slab S width. Figure 5 is a conceptual diagram showing the roll length being longer than necessary FIG. 3 is a conceptual diagram of the case where 1...Iron core, 11...Iron core body, 12...Iron core salient pole part, VC...V phase coil, UC...U phase coil, C...auxiliary coil.

Claims (1)

[Claims] 1. In a multi-strand continuous casting equipment equipped with a plurality of strands S ₁ to _{S o} (n is an integer of 2 or more) in which an electromagnetic stirring device is arranged in a mold, an electromagnetic stirring device is formed for each strand. A plurality of strands S ₁ ~
At the same time, the V-phase coils VC ₁ to _{VC 2o} disposed in each strand are integrated in adjacent strands so that the V-phase magnetic flux path is continuous across the plurality of strands S _{1 to S o} . An in-mold electromagnetic stirring device for multi-strand continuous casting equipment, characterized in that the winding direction of the coil is reversed.