JPH0425332B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a vacuum metallurgy device, and more specifically,
Regarding molds with variable width in vacuum metallurgy equipment such as plasma melting furnaces and electron beam (EB) melting furnaces.

(Conventional technology and problems to be solved) Vacuum metallurgy equipment such as plasma melting furnaces and EB melting furnaces are capable of high-purity melting and high-yield addition of alloying elements, so they have become high-quality products in recent years. It is becoming increasingly used. Therefore, high efficiency operation of vacuum melting equipment is required,
In particular, it is desired to develop a technology that enables rapid casting of various sizes.

It is considered advantageous to make the mold variable in order to enable such casting, but in conventional vacuum metallurgy molds, the insert that comes into contact with the molten metal is integrated with the hearth. Due to problems inherent to vacuum metallurgy equipment, such as seals, in reality, there were no variable width molds for slabs. This point will be explained in detail as follows.

Continuous steel casting equipment employs automatic width variable molds, which enable continuous operation and greatly contribute to improved productivity. As is well known, this automatic width-variable mold is equipped with various mechanisms necessary for varying the width, such as a wide-sided opening mechanism, a wide-sided clamping mechanism, and a narrow-sided feeding mechanism. To change the size, first, (1) operate the rotary actuator to move the wide-surface clamp screw shaft backwards to release the clamp, and then (2) operate the wide-surface opening cylinder to open the wide-surface clamp screw shaft. After expanding the gap, (3) the narrow surface feed drive is transmitted to the narrow surface feed drive screw shaft via a worm reducer, and by rotating this, the narrow surface feed screw shaft is moved forward and backward to change the size. I do. and,
(4) Clamp the wide surface again to complete the size change.

However, if the automatic width variable mold for continuous casting of steel as described above is directly adopted as a mold for vacuum metallurgy, the following problems (1) and (2) arise.

(1) In order to change the width of the mold, drive equipment such as a motor, reducer, and cylinder is required.
Generally, these devices on the market do not have seals that can withstand vacuum on the drive shaft, which causes problems such as evaporation of lubricating oil, and the casing material of the reducer is Since cast steel is generally used, there are various problems in terms of vacuum measures, such as being unsuitable for use in a vacuum container.

(2) In order to solve these problems, even if the sealing method and material of the motor, reducer, etc. are changed to those for vacuum use, and the seal on the exit side of the screw shaft for narrow surface feeding is changed to one for vacuum use, Even if it becomes a thing,
A new problem remains that it is no longer possible to absorb (breathing) changes in the volume of the internal space as the mechanism operates.

On the other hand, as another measure, it is possible to prepare a mold according to the size for product size change in vacuum metallurgy and replace the mold every time the size is changed. It is necessary to once open the melting chamber to the atmosphere, and considering the time required for evacuation and mold replacement, there is a problem that the casting cycle time will inevitably become longer. It is impossible to respond to the request.

The present invention has been made to solve the problems of the prior art described above, and it is possible to change the mold size more quickly without opening the vacuum container of the vacuum metallurgy device to the atmosphere, and at the same time The object of the present invention is to provide a variable width mold for vacuum metallurgy that does not contaminate a container with oil leakage.

(Means for Solving the Problems) In order to achieve the above object, the present invention makes the mold itself a vacuum chamber type, and makes the driving equipment required for changing the width of the mold an external type. In a vacuum metallurgy apparatus having a mold with a variable width, the mold itself is configured as a vacuum chamber type, and drive equipment such as a motor, reducer, cylinder, etc. required for changing the width of the mold is connected to the vacuum chamber. An externally mounted drive device for vacuum metallurgy with a variable width, which is disposed on the outside atmosphere side, and the drive shaft of the drive device penetrates the outer wall of the vacuum chamber and is connected to the mold. It's in the mold.

The present invention will be explained in detail below based on illustrated embodiments.

(Example) Figures 1 and 2 show a variable width mold according to an example of the present invention, where Figure 1 is a plan view and Figure 2 is a plan view.
The figure is a side sectional view.

In the figure, 1 is a mold chamber, and a pair of wide surfaces 2
The mold itself, which consists of a pair of narrow surfaces 3 and 3, is configured as a vacuum chamber mold that is airtightly independent from the melting chamber 10. Therefore, a mold chamber 1 is connected to the lower part of the melting chamber 10, and a drawing chamber 1 is connected to the lower part of the mold chamber 1 via a bellows 9.
1 are connected (Figure 2). It goes without saying that the chambers are connected by an appropriate sealing mechanism.

Since the mold chamber 1 has the above configuration, only the drive shaft required for changing the size of the mold is passed through the outer wall of the mold chamber 1, and drive mechanisms such as a wide surface clamp mechanism, a wide surface opening mechanism, and a narrow surface feeding mechanism are placed on the atmosphere side. It can be configured independently of the lysis chamber 10. Of course, the mold and its width variable drive mechanism are connected to the melting chamber 10, i.e.
Since it is not placed inside a vacuum container, it can be designed without being restricted by the space inside the vacuum container, and there is no problem with breathing mechanisms.

The wide surface 2 is slidably provided in the mold chamber 1 via a wide surface support 8, and the distance between the wide surfaces 2 facing each other is variable when changing the size. This wide surface 2
A wide-surface clamp shaft 7 of a wide-surface clamp mechanism 6 disposed on the atmosphere side is connected to the mold chamber 1 by penetrating its outer wall. Further, the wide surface opening mechanism may be connected to the wide surface 2 in the same manner, but in this embodiment, the wide surface clamping mechanism 6 is configured to also serve as the wide surface opening mechanism.

On the other hand, the narrow surface 3 is also provided so as to be slidable, and the narrow surface feeding mechanism 4 is arranged on the atmospheric side of the mold chamber 1.
A narrow face feed shaft 5 passes through the outer wall of the mold chamber 1 and is connected to the narrow face 3.

Note that the driving parts for the wide surface clamp (opening) mechanism, the narrow surface feeding mechanism, etc. may be a motor, a speed reducer, a cylinder, etc., and are not particularly limited, as in the case of continuous casting of steel.

(Operation) In the mold of this embodiment, the width change is performed in the following order.

First, by retracting the wide-surface clamp shaft 7 using the wide-surface clamp mechanism 6, the wide-surface clamp is released and at the same time the interval between the wide surfaces 2 is widened (wide-surface opening). Next, the narrow surface feed mechanism 4 moves the narrow surface 3 forward or backward via the narrow surface feed shaft 5 to change the narrow surface interval to a desired size. Finally, the wide-surface clamping shaft 7 is moved forward to perform wide-surface clamping, and the size change is completed.

It goes without saying that the present invention can be applied to molds for slabs and other slabs of various sizes and shapes, and can also be applied to various vacuum melting furnaces such as plasma melting furnaces and EB melting furnaces.

(Effects of the Invention) As detailed above, according to the present invention, the mold for vacuum metallurgy itself is a vacuum chamber type, and the driving equipment required for changing the width of the mold is an external type that is placed outside the vacuum chamber. The size of the mold can be changed quickly without exposing the vacuum container to the atmosphere each time, and the cycle time can be significantly shortened, thus meeting the demands for high efficiency and high productivity of vacuum metallurgy equipment. It is possible to respond. Furthermore, the possibility of contaminating the vacuum container due to oil leakage from drive equipment required for size changes can be reduced, and since these drive equipment can be breathed, there is no need to change seals, materials, etc. specifically for vacuum use. Since there is no restriction on the space inside the vacuum container, it is expected that the structure will be simplified and the workability will be improved.

[Brief explanation of drawings]

1 and 2 are diagrams showing a variable width mold for vacuum metallurgy according to an embodiment of the present invention, with FIG. 1 being a plan view and FIG. 2 being a side sectional view. 1...mold chamber, 2...wide surface, 2...narrow surface, 4...
Narrow surface feed mechanism, 5... Narrow surface feed shaft, 6... Wide surface clamp mechanism, 7... Wide surface clamp shaft, 8... Wide surface support, 9... Bellows, 10... Melting chamber, 11...
Pull-out chamber.

Claims (1)

[Claims] 1. In a vacuum metallurgy device having a mold with a variable width, the mold itself is configured as a vacuum chamber type, and drive equipment such as a motor, reducer, cylinder, etc. required for changing the width of the mold is placed outside the vacuum chamber on the atmosphere side. 1. A variable width mold for vacuum metallurgy with an external drive device, characterized in that the drive shaft of the drive device penetrates the outer wall of the vacuum chamber and is connected to the mold.