JPS5874258A - Method and device for charging of moltem metal in continuous casting - Google Patents

Abstract

PURPOSE:To maintain the discharge flow from a charging nozzle uniformly at a low velocity and to obtain a good thin-walled ingot by forming the sections of a charging nozzle and upper, middle and lower nozzle plates for charging molten metal into a mold where the molten metal passes into rectangular shapes. CONSTITUTION:Upper, lower nozzle plates 4, 6 having charging holes 3 of a rectangular section are provided in the lower part of a tundish 1. A middle nozzle plate 5 having a charging hole of the same shape as that of the plates 4, 6 is provided between the plates 4 and 6 freely slidably in the direction perpendicular to the down flow direction of molten metal. The molten metal is admitted into a charging nozzle 8 having the outflow hole of the rectangular section same as or similar to that of the plates 4, 5, 6 of such sliding mechanism 7. Thus the discharge flow from the nozzle 8 is maintained uniformly at a low velocity and a good thin-walled ingot is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pouring method and apparatus for thin-walled high-speed continuous casting of lK, which maintains a uniform downward flow of Sm metal in a mold during continuous casting of molten metal.

Conventionally, when continuously casting II metals, injection work was generally performed using a combination of an upper nozzle provided at the bottom of the tundish and an injection nozzle having a circular cross section.

The amount of molten metal injected is controlled by a stopper head or sliding nozzle mechanism.

The tip shape of the injection nozzle is either a straight type or a type with multiple discharge holes, but in both cases, the solidified shell is melted and eroded by the rapid discharge flow from the discharge hole (referred to as shell washing). , once the coagulation has started,
The powder on the surface of the molten metal inside the caster is engulfed by the rapid discharge flow, causing the grain to repopulate.
II Floating of impurities such as non-metallic inclusions in molten metal -
It has disadvantages such as being sluggish.

Moreover, in the case of thin-wall continuous casting, high-speed casting is essential for rounding to ensure precision, but it is impossible to increase the inner diameter because it is necessary to increase the amount of molten metal supplied into the mold. It is. What is a question?

The injection nozzle of the conventional type with a circular cross section m has a defect that makes it unusable.Th,9. There is a need for a new injection method and apparatus for thin-wall, high-speed continuous casting.

The present invention solves the problems in the prior art, and 1-
1. For thin-walled metal high-speed continuous casting. This was done for the purpose of casting while maintaining the discharge flow from the injection nozzle at a -41 low speed downward flow.

That is, the 1# image of the present invention is that an apparatus for continuously casting molten metal has an injection hole with a rectangular cross section, and
It has a V-nozzle plate and injection holes having the same shape as the injection holes of the upper and lower nozzle plates. A sliding nozzle mechanism constituted by a middle nozzle plate sandwiched between the plates and an injection nozzle having a rectangular cross section similar to the plate and fwl--* are combined to inject the liquid into the mold. The present invention relates to a molten gold injection method and apparatus.

The method and apparatus for injecting molten metal in continuous casting by explosion will now be described in detail with reference to the drawings.

In FIG. 1, an upper nozzle 2 installed in the lower part of a tundish has an injection hole 3 with a rectangular cross section.

Soil, upper nozzle plate 4 for nozzle 2. + Nozzle pre-
-G5. Lower nozzle plate 60 A sliding nozzle mechanism 7 composed of three nozzle plates is attached, and an injection nozzle 8 is connected to the lower part of the sliding nozzle mechanism 7. The injection nozzle 8 has a shape having a rectangular cross section identical to or similar to the plate.

Cast! II9 has a small cross-sectional shape, and is equipped with a sliding nozzle machine &7 [*], and casting is performed with the injection nozzle 8 immersed in the molten metal 10 in the mold 9. The middle nozzle plate 5 is caused to reciprocate in a direction perpendicular to the direction in which the molten metal flows down by two drive mechanisms (not shown), such as a hydraulic cylinder rC. Between the casting speeds UFi is carried out by the plate 5 in the sliding nozzle. Casting 1. Soil nozzle plate and lower nozzle plate 2.
It is also conceivable that this could be done by sliding the lower nozzle plate of a sliding nozzle mechanism consisting of two plates.

The injection nozzle connected to the lower nozzle plate slides at the same time as the lower nozzle plate, allowing thin-walled high-speed #Ik
In the case of steel casting, the slab thickness direction Fi in the cast iron is narrower.

The excitation width is too small (not practical). Therefore, it is necessary to carry out the taut with the middle nozzle plate of the sliding nozzle, which is composed of three plates in which the madman nozzle is fixed. In addition, in the case of thin-wall, high-speed casting, if the cross section of the injection nozzle is the circular cross section of a conventional lid, the cross section of the nozzle for injecting molten metal must become smaller and smaller due to restrictions on the cross-sectional shape of the mold. The amount of offerings is insufficient. Therefore, it is necessary to make the cross section of the injection nozzle oriented in a rectangular llr direction in the longitudinal direction of the casting mold, and to increase the shear area so as to increase the amount of molten metal supplied.

Secondly, is the molten metal injection device for continuous casting according to the present invention configured as described above?

The effect will be explained below.

Continuous casting begins at K, and metal is supplied to the mold K11ll from the tandish through the upper nozzle, the sliding nozzle mechanism, and the large nozzle a. When the tip of the injection nozzle is immersed in sm*i4 in the mold, the inside of the injection nozzle is filled with molten metal jII&, and a low-speed downward flow flows uniformly across the inside of the injection nozzle, causing r( In addition, when the drawing of the slab is started, the injection nozzle is immersed in the molten metal bath in the mold - lower 1/C, and the molten metal bath surface in the mold is maintained constant). The supply amount is controlled by adjusting the opening FIL of the middle nozzle plate.

Next, two embodiments of a continuous casting method for molten metal according to the present invention will be described.

Medium carbon ordinary steel melted in an electric furnace is tapped into a ladle.

Transfer it to a stand so that it can be installed on the tundish for continuous casting. The upper nozzle is pre-installed at the bottom of the tandy for ≧ 15mm IJ
A sliding nozzle mechanism consisting of three plates each having an injection hole with a rectangular cross section of 300 mm is combined with an injection nozzle having the same cross section ifO as the injection hole in the -u distribution plate. Next, lower and secure the tundish until the injection nozzle is inserted into the predetermined position within the #N mold. The mold used was ′igoξIJ
This is the cross-sectional shape of MIIJ for producing thin slabs. In the pouring process, the H1 nozzle grate of the sliding nozzle is opened and molten copper is injected into the mold through the tundish injection nozzle, and is injected until the specified position in the M mold, the so-called injection nozzle, is immersed in the mold self-melting. Next, powder was introduced and drawing of the cast slab was started while oscillating the mold, and the injection speed was adjusted by adjusting the middle nozzle plate once to set the drawing speed to tia/min. The inside of the injection nozzle is filled with molten steel, and a uniform low-speed downward flow is obtained within the rectangular section (3) of the injection nozzle and reaches the mold, and the inside of the mold is quiet with no violent downward flow or stirring flow. ) Casting was carried out in rII# flow. The obtained slab was uniformly solidified without any melt erosion of the solidified shell due to the arc in the discharge, had good wood quality, and had few nonmetallic inclusions.The present invention is constructed as described above, In order to supply a large amount of molten metal during continuous casting of molten metal, especially during high-speed continuous casting in the stomach, the molten metal passing lr surface of the injection nozzle and sliding nozzle plate is made rectangular. By using VC on the wI surface, it is possible to cast, and the discharge flow from the injection nozzle can be maintained in a uniform downward flow, resulting in good slabs and industrially significant young fruit production. It's falling apart.

[Brief explanation of the drawing]

Navy blue Figure 1 Fi, section 111 showing a conventional S* gold metal injection device
Figure 11. FIG. 2 is a longitudinal sectional view showing a molten metal injection device according to the present invention. Copper Figure 3 is the cross section LK shown in Figure 2 & longitudinal section i*1 in the straight direction.
It is a diagram. 1: Lower tundish, 2: Upper nozzle, 3: Soil nozzle sweat inlet 1.4: Upper nozzle plate, 5: Middle nozzle plate, 6: Lower nozzle plate, 7: Sliding nozzle mechanism, 8: Injection nozzle, 9: mold, lO: molten metal in mold. (Embedded) Patent Attorney Masaaki Akizawa Mitsunobu 2 people Left 1 Figure 7? 2 Figure 6 3 Figure

Claims (1)

[Scope of Claims] (υ When continuously casting molten metal, an upper nozzle plate is provided at the bottom of the tundish and has an injection hole of the same shape as the lower nozzle plate. At the same time, the upper nozzle is slidably in a direction perpendicular to the downward direction of the K11M metal.The S-
While controlling the amount of metal to be injected, the molten metal is uniformly introduced into the mold by flowing into an injection nozzle having an outflow hole with a rectangular cross section that is the same as that of the plate connected to the sliding nozzle mechanism marked #, or having a rectangular cross section. 1lI in continuous casting characterized by supplying a downward flow of molten metal at a flow rate
Method of implanting Wa metal. (2) Upper and lower nozzle plates with a rectangular injection hole in the lower part 11, and an injection hole with the same shape as the injection hole in the upper and lower nozzle plates, and substantially #1m metal. Towards the blade! A sliding nozzle mechanism is provided between the upper and lower nozzle plates so as to be slidable in the direction of ii&, and a sliding nozzle mechanism constituted by a middle nozzle plate is provided. A molten metal injection device for continuous casting, comprising an injection nozzle having a cross-sectional pouring hole connected to the sliding nozzle mechanism.