JPH0251706B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a molten metal flow rate control device used when pouring molten metal from a molten metal container such as a ladle or a tundish.

[Conventional technology]

When pouring molten metal from a molten metal container, a nozzle stopper system and a slide valve (sliding nozzle) system are well known as mechanisms for controlling the flow rate of molten metal.

[Problem that the invention seeks to solve]

It is known that the drawbacks of the conventional method are as follows: Nozzle stopper method (1) Since the nozzle stopper 1 is required to have a length that is approximately the same as the height of the molten metal container, it is difficult to use refractory material. (2) As shown in Figure 15 (relationship diagram between the stroke and opening area of the slide valve and nozzle stopper), a slight movement of the nozzle stopper 1 causes a large change in flow rate, resulting in poor flow rate controllability. (3) Since the nozzle stopper 1 is immersed in the molten metal, trouble may occur where the nozzle stopper 1 is cut vertically due to melting damage or thermal spalling, making it impossible to control the flow rate.

Slide valve method (1) In the case of a ladle, from the time the molten metal is received into the ladle until the molten metal is poured out (hereinafter referred to as casting), it takes several tens of minutes to several minutes depending on the composition adjustment and temperature adjustment of the molten metal. It took hours.

Therefore, it is necessary to fill the nozzle 2 with a filler such as sand to prevent the molten steel from solidifying within the nozzle 2, resulting in poor work efficiency. The filling material is
When the slide valve is opened, the filling material flows out first, and then the molten metal flows out, opening the valve naturally. Therefore, it is necessary to forcibly open the opening using an oxygen lance, which is a dangerous task.

(2) In the case of a tundish, it is not possible to use fillers etc. due to the quality of the molten metal, and a refractory material or iron pipe, etc. is installed around the top of the nozzle so that the hole opens after the molten metal has accumulated in a specified amount. It is necessary, the workability is poor, and the cost is high.

(3) In the case of a tundish, a fixing plate 3 as shown in Fig. 16 is used instead of a refractory or iron pipe, etc.
Alternatively, there is a method of blowing inert gas through the slide plate 4 to prevent the molten metal in the nozzle from solidifying, but in this case, the structure for introducing the inert gas is complicated and the cost is high.

Furthermore, even with the above method, the success rate is not 100%, and there are cases where the molten metal in the nozzle solidifies and the casting does not start.

Even when replacing the immersion nozzle during casting,
Same as above to close the nozzle.

(4) The nozzle may be fully closed due to errors or necessity during casting, but if it is fully closed for a long time, the molten metal will solidify inside the nozzle, making it necessary to forcibly open the hole.

(5) Since there are many joints and there is a high risk of air being drawn in from outside the refractory, there is a high possibility that product quality will be adversely affected.

Also, as a recent technology, there is a rotary valve shown in FIG. 17, and the feature of this system is that it is composed of a rotor 20, a dome nozzle 21, and a drive mechanism 20a. The flow rate of molten metal is controlled by rotating the molten metal, but this type of system also has the following drawbacks.

(1) Since the rotor 20 is immersed in the molten metal, the middle part of the rotor 20 may be cut vertically due to melting damage or thermal spalling, which may make it impossible to control the flow rate.

(2) The length of the rotor 20 is
The cost is high because the length is longer than the height of the

(3) In the initial stage of casting, the nozzle 22 is fully closed and the molten metal is injected into the tundish 23. After the molten metal reaches a certain amount, the nozzle 22 is opened and the casting operation begins. For some reason, it cannot be made too large, and the temperature of the molten metal inside the nozzle 22 may drop, causing the molten metal to solidify, making it impossible to start casting.

That is, in order to increase the size of the nozzle 22, the rotor 20, dome nozzle 21, and other related components must also be increased in size, which causes problems such as increased cost and ease of handling, and there is a limit to the size increase.

In addition, in the case of an emergency situation such as an operational error during casting work or an overflow of molten metal in the mold, the nozzle 22 may be fully opened, but as described above, the molten metal in the nozzle 22 will solidify and it will be impossible to restart casting. It may happen.

(4) Since the rotor 20 is large and heavy, handling of the rotor 20 and workability during setting are poor.

[Means for solving problems]

The present inventors have successfully developed the present invention as a result of various studies and experiments in order to solve the various deficiencies of the conventional system, and the technical configuration of the present invention is as specified in each claim of the above claims. However, the present invention will be explained in more detail based on the accompanying drawings showing several specific examples of the present invention.

As shown in FIG. 1, a nozzle receiving brick 6 is fixed with mortar to the bottom or side of the molten metal container 5.
Fix the sleeve 7 with mortar, and
It consists of a rotating nozzle 8 that is in close contact with the inner taper part or the straight part of the molten metal and is rotatably supported by a rotation control case 10 (hereinafter simply referred to as the case).By rotating the rotating nozzle 8, the molten metal is It controls the flow rate.

Next, the present invention will be specifically explained based on FIGS. 1 to 5. As shown in FIGS. 1 and 5, the rotating nozzle 8 has a truncated conical shape, and the lower part has one or more driving holes parallel to the axis of rotation of the rotating nozzle 8, as shown in FIG. A flat surface is provided, and an L-shaped nozzle hole 9 is provided below the tapered portion of the side surface, and a sleeve 7 and a nozzle receiving brick 6 are provided so that molten metal flows into the nozzle hole 9 of the tapered portion.
A concave cutout 25 is provided in the holder.

The concave notch is a notch provided in at least one place from the top surface to the side surface of the nozzle receiving brick 6 and sleeve 7, as shown in FIGS. 3 and 4, and it may be a straight cut or a curved cut. Zumata refers to the cutout part regardless of the shape.
The sleeve 7 is fixed to the nozzle receiving brick 6 with mortar so as not to rotate. The rotary nozzle 8 and the sleeve 7 are supported by a case 10 in order to bring them into close contact with each other to prevent molten metal from entering the contact surfaces thereof, and to hold the rotary nozzle 8 rotatably. Case 1
A transmission means (not shown) such as a gear or a link is provided on the outer circumference of 0 to transmit rotational force.
It is driven and controlled by a driving device (shown in FIG. 11) such as an electric motor, a hydraulic motor, or a hydraulic cylinder.

Next, a method of using the control mechanism of the present invention configured as described above will be explained. First, the rotary nozzle 8 is rotated, and the nozzle hole 9 is moved to a location other than the concave notch 25 of the sleeve 7 and the nozzle receiving brick 6.
The nozzle hole 9 is closed, and the molten metal is received into the molten metal container.

In casting, the rotary nozzle 8 is rotated to align the nozzle hole 9 with the concave notch 25 of the sleeve 7 and the nozzle receiving brick 6, thereby causing the molten metal to flow out.

The outflow control is performed by rotating the rotary nozzle 8 and closing (squeezing) the nozzle hole 9 with the edge of the concave notch 25 of the sleeve 7, as shown in FIG. Further, such flow rate control is possible at two locations, A part and B part in FIG.

Although the above description has been made based on one embodiment of the present invention, the size of the concave notch of the sleeve 7 and the nozzle receiving brick 6 may be large enough to prevent the nozzle hole 9 of the rotating nozzle 8 from being blocked.

Further, the number of the nozzle hole 9 and the recess 25 is not limited to one, but may be provided at several locations.

As shown in FIGS. 6 and 7, the rotating nozzle 8 has a straight outer circumference (cylindrical shape) 8.
a, it may be an inverted tapered shape (inverted truncated conical shape) 8b.

Further, the shape of the nozzle hole 9 may be a straight through hole 9a diagonally from the tapered surface as shown in FIGS. 8 and 9 a and b, or the cross-sectional shape thereof may be an ellipse 9b.

The combination of the rotating nozzle 8, the sleeve 7, and the nozzle receiving brick 6 is the first combination in addition to the above-mentioned combination of the rotating nozzle 8, the sleeve 7, and the nozzle receiving brick 6.
As shown in FIG. 0, it can also be combined with a rotating nozzle 8 and a nozzle receiving brick 6c.

An embodiment of a support device for the rotating nozzle 8 is shown in FIG. A case 10 held by the lower flat surface of the rotating nozzle is rotatably held by an outer case 11 so that rotation is imparted to the rotating nozzle 8, and bolts and
It is fixed by a nut 12 to a fixed base 15 which is welded or bolted to the molten metal container 5. A gear is cut on the outer periphery of the case 10, and the outer case 1
A deceleration gear 13 is provided between the rotary nozzle 8 and the worm gear 14, and a worm gear 14 is provided on the outside thereof, and a drive source (not shown) such as an electric motor or a hydraulic motor is provided in the worm gear.
The rotation control is performed.

Next, a 13th embodiment in which an intermediate nozzle 16 is incorporated is shown.
This will be explained based on the diagram.

The rotating nozzle 8, the sleeve 7, and the nozzle receiving brick 6 are similar to those shown in FIG.

The intermediate nozzle 16 is brought into close contact with the rotating nozzle 8 by a case 17 and is fixed so as not to move even if the rotating nozzle 8 rotates.

The interface between the intermediate nozzle 16 and the rotary nozzle 8 is a flat surface or a spherical surface 8 as shown in FIGS. 13 and 14.
e, 16a or one or more projections and recesses 8f, 16b may be fitted.

Note that this mechanism is effective when using a lower nozzle such as a submerged nozzle or a long nozzle.

〔Effect of the invention〕

According to the flow control mechanism of the present invention, as described above,
All the problems of the prior art have been solved, and the present invention is especially excellent in the following points.

(1) At the start of casting, no molten metal enters the nozzle hole 9, so not only is there no need for a filler, but there is no need to blow inert gas.
Therefore, costs are low and stable operation is possible.

(2) Even when replacing the immersion nozzle etc. during casting,
Since molten metal does not enter the nozzle hole 9 when the nozzle is closed, the same effect as in the previous item (1) is obtained.

(3) Compared to slide valves, there are fewer joints, which reduces air entrainment from the outside and improves product quality.

(4) It is compact and requires less refractory material, resulting in lower costs. Also, the work of replacing the refractory members is easy.

(5) Since the flow rate can be controlled at two locations, A and B, as shown in Fig. 2, the flow rate control performance is better than in the prior art, and the service life is longer.

[Brief explanation of the drawing]

Figures 1 to 14 are schematic diagrams showing specific examples of the device of the present invention, Figure 15 is a graph showing the relationship between the stroke and opening area of the slide valve and nozzle stopper system, and Figures 16 and 17 are known It is a schematic diagram of an example, and in the figure, 5... Molten metal container, 6... Nozzle receiving brick, 7... Sleeve, 8... Rotating nozzle, 9... Nozzle hole, 10, 17... Case, 1
1... Outer case, 12... Bolt/Nut, 13
... Reduction gear, 14 ... Worm gear, 15
... Fixed base, 16 ... Intermediate nozzle, 20 ...
Rotor, 21... Dome nozzle, 22... Opening hole, 23... Tundish, 25... Concave notch.

Claims (1)

[Scope of Claims] 1. A molten metal flow rate control device that can be disposed at the bottom or side of a molten metal container, comprising a rotating nozzle, a nozzle receiving brick, and a sleeve, or a rotating nozzle, a nozzle receiving brick, and the nozzle receiving brick and the sleeve. One or more concave notches are provided in at least one side of the sleeve, and the nozzle opening surface of the rotary nozzle passing through at least one nozzle hole is rotatably brought into close contact with the inner peripheral surface of the nozzle receiving brick or sleeve. A molten metal flow rate control device, characterized in that a rotating mechanism is provided on the rotating nozzle supported by the rotating nozzle and mounted so that the upper part of the rotating nozzle is in contact with the molten metal. 2. The molten metal flow rate control device according to claim 1, wherein the rotating nozzle has a shape of a truncated cone, an inverted truncated cone, or a cylinder. 3. The molten metal flow rate control device according to claim 1, wherein the nozzle hole cross section of the rotating nozzle is circular or elliptical. 4 Place the intermediate nozzle closely on the lower end surface of the rotating nozzle,
The molten metal flow rate control device according to any one of claims 1 to 3, wherein the molten metal flow rate control device is fixed. 5. The molten metal flow rate control device according to any one of claims 1 to 4, wherein the fitting surfaces of the rotating nozzle and the intermediate nozzle have a flat surface, a spherical surface, or an uneven surface. 6. The molten metal flow rate control device according to claim 1, wherein the rotary nozzle is supported by a rotation control case. 7. A molten metal flow rate control device that can be disposed at the bottom or side of a molten metal container, comprising a truncated conical rotating nozzle, a nozzle receiving brick, and a sleeve, or the rotating nozzle and the nozzle receiving brick, wherein the nozzle receiving brick and sleeve have a The nozzle opening surface of the rotary nozzle is provided with at least one concave notch, and the nozzle opening surface of the rotary nozzle passing through at least one nozzle hole is closely and rotatably supported on the inner circumferential surface of the nozzle receiving brick or sleeve. A molten metal flow rate control device characterized in that a rotating nozzle is equipped with a rotating mechanism.