JPH0635045B2 - Ingot drawing device in electroslag remelting furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is an ingot extraction method for extracting ingots ingot in an electroslag remelting furnace, which is one of high-grade steel manufacturing apparatuses, at a constant speed for extraction. It relates to the device.

BACKGROUND OF THE INVENTION An electroslag remelting furnace (ESR furnace) is a well-known method in which a consumable electrode is immersed in molten slag in a water-cooled mold.
The consumable electrode is melted by electric resistance heating generated in the molten slag, and the consumable electrode melts its tip sequentially by the heat and is dropped as molten droplets into the molten slag, and the dropped melt The droplets form a molten steel pool in a water-cooled mold, which is surrounded by a thin layer of solidified slag formed on the inner surface of the mold and solidified to sequentially form an ingot. Then, as the ingot grows, the water-cooled mold a is raised as shown in FIG. 4, and the ingot b is lowered while the water-cooled mold a is fixed as shown in FIG. The method of getting there has always been the method. In addition, in FIG. 4 and FIG. 5, c
Is a consumable electrode, d is a support for the ingot b, e is molten slag accumulated in the water-cooled mold a, and f is a molten steel pool.

However, ingot b that can be ingot in any case
Was restricted to a certain length or less by the movable stroke of the water-cooled mold a or the movable stroke of the support base d.
For this reason, every time an ingot of a certain length is ingot, dissolution must be stopped, the ingot should be removed, and then ingot ingot of a certain length must be started again, which leads to good productivity and yield. It was not there.

In order to solve such a problem, the inventors of the present invention provided two grippers for gripping the ingot sequentially extracted from the lower opening of the water-cooled mold so as to move up and down by respective motors, and extracted from the water-cooled mold. While holding the ingot held by one of the grippers, the gripper is lowered in accordance with the extraction speed of the ingot, and the other gripper grips the ingot before the gripper reaches the lower limit of its lifting stroke. The gripper is subsequently lowered in accordance with the extraction speed of the ingot, and the gripper releases the grip and rises to re-grip the upper part of the ingot, and thereafter, both grippers are alternately pulled out. The electroslag remelting furnace was developed to enable continuous formation of desired long ingots, and the invention was filed separately from this case. It is intended to provide a device for pulling the Ingotsuto for extraction from the water-cooled mold in electroslag remelting furnace as a.

[Problems of Prior Art] The following points are problems in such a drawing device. That is,
Since the ingot is pulled out while being alternately supported by both grippers, the pulling speed, that is, the descending speed of both grippers must be exactly the same in a strict sense. If there is a difference in the speeds, a slip may occur between the ingot and the gripping surface of the gripper at the moment when the supporting is changed, and there is a concern that the gripping device may be subjected to an excessive force and the device may malfunction.

[Means for Solving Problems] The ingot gripping device of the present invention is intended to solve the above-mentioned problems. A consumable electrode is immersed in molten slag accumulated in a cylindrical water-cooled mold from above to melt the melted slag. An electroslag remelting furnace in which the consumable electrode is melted by electric resistance heating generated in the slag, and ingots formed by solidifying the droplets are sequentially extracted from the lower opening of the water-cooled mold. In the above, a pair of grippers for gripping the ingot are arranged so as to move up and down while being guided by a pair of vertically supported screw shafts, respectively, and the power of one extraction motor that rotates at a constant speed is controlled by a gear box. Via two transmission shafts, each transmission shaft is connected to the screw shaft with an electromagnetic clutch interposed, and the screw shaft is reversed to the driven side of the electromagnetic clutch of the transmission shaft to raise the gripper. The restoration motors are connected to each other via gear boxes.

[Operation] Since both grippers descend by the operation of one pulling motor that rotates at a constant speed, the descending speed is always the same for both grippers.

[Embodiment] Next, an embodiment of the present invention will be described with reference to FIGS. In the figure, 1 is a cylindrical water-cooled mold supported on a pedestal 2, 3 is a consumable electrode suspended therein, and 4 is a mold 1.
It is an ingot that was made in the inside. Support 2a of the gantry 2,
Linear bearings 5a, 5a, 5 inside 2a, 2b, 2b
b and 5b are provided, and the grippers 6a and 6b are provided so as to be vertically movable along the column. Both grippers 6a, 6b are pivotally supported by supporting shafts 8a, 8a, 8b, 8b so that a pair of fingers 7a, 7a, 7b, 7b can be opened and closed respectively, and the tips of the fingers are attached to both side surfaces of the ingot 4. The cylinders 9a and 9b are interposed between the other ends of the fingers so as to face each other, and when the cylinders 9a and 9b are extended, the fingers are moved so that the tips thereof grip the ingot 4. LS1a and LS1b are limit switches provided to detect the gripped state.
On the other hand, 10a and 10b have bearings 11a, 12a and 11 at the upper and lower ends, respectively.
screw shafts vertically supported by b and 12b so that female screw bodies 13a and 13b provided on the backs of the grippers 6a and 6b are screwed to the screw shafts 10a and 10b. There is.
Therefore, when the screw shafts 10a, 10b rotate, the grippers 6a, 6
b is moved up and down. LS2a, LS
2b is a limit switch attached to the columns 2a and 2b for detecting the rising end of the grippers 6a and 6b, LS3a,
The LS3b is a limit switch provided on the columns 2a and 2b for detecting the descending end of the grippers 6a and 6b, and LS4.
a, LS4b is this limit switch, LS3a, LS
The limit switches are provided a little above 3b. A melting current is constantly applied to the ingot 4 through the grippers 6a or 6b.

Reference numeral 14 is a single extraction motor provided on the pedestal 2, and the extraction motor is preferably a direct-current motor for obtaining a variable speed. A three-axis orthogonal type gear box 16 is connected to a rotary shaft 15 of the pull-out motor 14, and its power is branched to two-direction transmission shafts 17a and 17b orthogonal to the rotary shaft 15. 18a and 18b are bearings that support the transmission shafts 17a and 17b. Reference numerals 19a and 19b denote electromagnetic clutches interposed between the respective transmission shafts 17a and 17b, and triaxial orthogonal type gear boxes 20a and 20b are further connected to the driven side of the respective electromagnetic clutches.
Reference numerals 21a and 21b denote restoration motors, which are rotary shafts 22a,
22b is connected to each of the gear boxes 20a and 20b.
Further transmission shafts 23a, 23 of the gear boxes 20a, 20b
b is connected to worm speed reducers 24a and 24b provided at the upper ends of the screw shafts 10a and 10b.

However, in the electroslag remelting furnace configured as described above, the extraction motor 14 is constantly rotated to maintain a constant speed. Then, the gripper 6a, which is now at the highest end, is lowered at the same speed as the ingot 4 extracted from the lower opening of the water-cooled mold 1 by connecting the electromagnetic clutch 19a. Then, the fingers 7a, 7a of the gripper 6a are closed, the ingot 4 is gripped, and the ingot 4 is pulled out. At the time of this withdrawal, the other gripping device 6b releases the gripping of the ingot 4 by the fingers 7b, 7b, disconnects the electromagnetic clutch 19b, and reverses the screw shaft 10b by the operation of the restoring motor 21b to return to the highest end. Put on hold. Eventually, when the gripper 6a approaches the descending end and the limit switch LS4a is operated, the electromagnetic clutch 19b is connected by the signal and the other waiting gripper 6b starts to descend, and after the set time by the timer, the fingers 7b and 7b Hold the ingot 4. Then, after the grip confirmation signal of the limit switch LS1b is obtained, the grip of the gripper 6a is released and the gripper 6a is released.
Further operates the limit switch LS3a to open the electromagnetic clutch 19a and at the same time restore motor 21
a is rotated and the gripper 6a is moved upward to return to the original end of the upward movement, and the waiting period is waited here. Meanwhile, the other gripper 6b is lowered by the pulling motor 14 in synchronism with the extraction speed of the ingot 4 to pull out the ingot 4. Similarly, the grippers 6a and 6b alternately grip the ingot 4 and continuously pull out the ingot 4. Note that the consumable electrode 3 is replaced in a timely and necessary manner. The ingot 4 is formed as long as necessary and can be cut into pieces with an appropriate length for use.

[Effects of the Invention] As described in the above embodiments, in the ingot extracting device of the present invention, one pulling motor that rotates at a constant speed is commonly used for lowering the pair of grippers. There is no difference in the descending speed of the device, and the gripping change by both gripping devices can be performed smoothly.
Since it is easy to synchronize with the ingot ingot speed, it brings about a beneficial effect on the quality of the ingot.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an electroslag remelting furnace showing an embodiment of the present invention, FIG. 2 is a plan view thereof, and FIG.
A sectional view taken along the line AA of FIG. 4, FIG. 4 and FIG. 5 are schematic diagrams for explaining the operating method of the conventional electroslag remelting furnace. 1 ... Water-cooled mold, 3 ... Consumable electrode, 4 ... Ingot,
6a, 6b ... Gripping device, 10a, 10b ... Screw shaft, 14 ...
Extraction motor, 16 ... Gear box, 17a, 17b ... Transmission shaft, 19a, 19b ... Electromagnetic clutch, 20a, 20b ... Gear box, 21a, 21b ... Restoration motor.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takeomi Taniyama 335-4 Irizawa, Shibukawa City, Gunma Prefecture (72) Inventor Tomio Inukai 269-1 Ishihara, Shibukawa City, Gunma Prefecture

Claims (1)

[Claims] 1. A consumable electrode is immersed from above in a molten slag accumulated in a cylindrical water-cooled mold, and the consumable electrode is melted by electric resistance heating generated in the molten slag, and the droplet size thereof is In an electroslag remelting furnace in which the solidified ingot is sequentially extracted from the lower opening of the water-cooled mold, a pair of grippers for holding the ingot are guided by a pair of vertically supported screw shafts. The power of a single extraction motor that rotates at a constant speed is split into two transmission shafts via a gear box, and the transmission shafts are interleaved with an electromagnetic clutch to form the screw shaft. And a restoring motor for reversing the screw shaft and ascending the gripper on the driven side of the electromagnetic clutch of the transmission shaft are connected to each other through gear boxes. Ingotsuto withdrawing apparatus according remelting furnace.