SU1271892A1 - Device for electric heating of vacuum chamber - Google Patents

Abstract

The invention relates to metallurgy, and more specifically to equipment for out-of-furnace vacuuming of liquid steel. The purpose of the invention is to simplify the construction, reduce the size, increase the reliability and improve the service conditions by installing a current insert,. hermetically installed between the adapter and the conductive rod. Electrode 1 is inserted inside the vacuum chamber 2 through hole 3 in its body 4, and between the current-carrying rod 5 I and adapter 6 is mounted water (L is cooled insert 8, electrically insulated from them. 2 Cpf-ly, 2 ill.

Description

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The invention relates to metallurgy, and more specifically to equipment for out-of-furnace vacuuming of liquid steel.

A device for electric arc heating of a metal in a vacuum chamber is known, which contains three electrodes inserted inside the vacuum chamber through openings in its cover 11.

Its disadvantage is the limited scope, due to the fact that the arc stably burns only when the pressure in the vacuum chamber is not lower than 200 mm Hg, as well as in the presence of metal in the chamber. These factors have a negative effect on the duration of the vacuuming process and on the capacity of the vacuumizer.

The closest to the invention to the technical essence and the achieved results is a device for electric heating of a vacuum chamber: an electrode containing an electrode inserted inside the vacuum chamber through an opening

in its case, the current-carrying water-cooled rod J the adapter is hermetically mounted on the case, the mechanisms for moving the electrode C 2.

The drawbacks of the devices are the complexity of its structures and the increased dimensions in length due to the presence of two different mechanisms for moving the electrode and the spacer. Other disadvantages are the reliability and unsatisfactory service conditions caused by the fact that the design is known in order to ensure close contact between the electrode and the electrical contact requires time-consuming manual adjustment of the electrode position to the open hole in the vacuum chamber from which The flame tongues are knocked out at the same time. In this case, satisfactory contact cannot be achieved in practice, since the abutting surfaces are located outside My visibility on parts mounted on various mechanisms mounted with inevitable distortions and deviations. As a result of the loose contact at the junction between the electrode and the spacer, the transitional resistance sharply increases, which means that

Local overheating of the electrode and premature termination of it. The purpose of the invention is to simplify the design, reduce the size, increase the reliability and improve the service conditions.

This goal is achieved by the fact that a known device for electrically heating a vacuum chamber, containing an electrode inserted inside a vacuum chamber through an opening in its housing, a current-carrying water-cooled rod, an adapter sealed to the housing, and

5, the mechanism for moving the electrode is provided with a current-carrying insert, which is hermetically mounted between the adapter and the bolster and is electrically insulated from them;

0 the electrode is made in the form of a hollow glass and is fixed on the current-carrying insert, and a part of the stefjn is passed inside the electrode with a gap and is in contact with its bottom,

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The gap between the rod and the wall

the electrode is filled with electrically insulating refractory material, for example, kaolin wool.

The current-carrying rod between the current-carrying insert and the electrode is provided with a stop.

Fig, 1 shows the device, a general view; in fig. 2 — node I in FIG. one.

5 The device soda} spits the electrode 1, inserted inside the vacuum chamber 2 through the hole 3 in its body 4, the current-carrying water-cooled rod 5, adapter 6, hermetically sealed, I1

 hinged on the case h, and the mechanism 7 for moving the electrode 1. Between the adapter 6 and the current-conducting core 5 a current-carrying water cooling insert 8 is installed, isolated from them

electrically by sleeves 9 and 10 and gland seals 11 and 12. Insert 8 is fixed relative to adapter 6 by tightening gland packing.

 The electrode 1 is made in the form of a hollow cup and is fixed to the insert 8 by means of a threaded connection. Between the insert 8 and the electrode 1, a bayonet5 of a type can also be made. Part of the current-carrying rod 5 is missed inside the electrode 1 with a gap of 13 and in contact with its bottom

14. The gap 13 between the rod 5 and the electrode 1 can be filled with an electrically insulating refractory material such as kaolin wool (not shown). On the current-carrying rod 5 between the electrode 1 and the insert 8, perform the stop 15.

The rod 5 is installed with the possibility of axial movement in the supports 16 of the mechanism 7 for moving the electrode and is isolated from them by bushings 17. The power supply is connected to terminals 18 and 19 located respectively on the insert 8 and the rod 5. On the rod 5 there is also a bar 20 made of an electrical insulating material and associated with the support 16 by means of two tension springs 21.

The device works as follows.

With the passage of current, the electrode 1 is heated to a temperature of about 2000 ° C and, due to radiation, heats the lining of the vacuum chamber 2 to an operating temperature of 1DOO-1500 ° C. If it is necessary to replace the worn electrode, adapter 6 disconnects the vacuum chamber 2, then by moving the mechanism 7 the rod 5 is retracted until the stop-15 touches the insert 8. When the rod 5 is further moved, the insert 8 moves together with the adapter 6 and electrode 1 to replace electrode. A new electrode is inserted in reverse order. After the flanges of the vacuum chamber 2 and adapter 6 are in contact, the mechanism 7 for moving the electrode 1 is stopped and the adapter 6 is fixed on the vacuum chamber 2. Then, the current-carrying rod 5 is pulled out by an additional stroke of the mechanism 7 until it touches the bottom 14 of the electrode 1 and is subsequently created by stretching the springs 21 working effort preload, equal to 700 kgf.

Compared with the known, the proposed device has a simpler design, smaller dimensions and reduced metal consumption due to the exclusion of the spacer movement mechanism, increased reliability of the Taccount of eliminating mutual displacements and distortions of the contacting parts, as well as simpler maintenance conditions due to the elimination of the need for out. areas of direct visibility of close contact of parts mounted on various mechanisms.

Claims (3)

1. A device for electrically heating the vacuum chamber, comprising an electrode inserted into the inside of the vacuum chamber through an opening in its housing, a current-carrying water-cooled rod adapter, hermetically mounted on the housing, and an electrode movement mechanism, characterized in that, in order to simplify the design, reduce the size, , increasing reliability and improving service conditions, it is equipped with an insert, hermetically installed between the adapter and the current-carrying rod and isolated from them electrically, while the electrode you filled in the form of a hollow glass and fixed to the currents of the driving insert, and a part of the rod is passed inside the electrode with a gap and contacts his bottom. 2. The device according to claim 1, wherein the gap between the rod and the electrode wall is filled with electrically insulating refractory material, for example, kaolin wool. 3. The device according to paragraphs. 1 and 2, differently in that the current-carrying rod between the current-carrying insert and the electrode is provided with a stop