JPH0351917Y2 - - Google Patents

Description

[Detailed explanation of the invention] <Purpose of the invention> Industrial application field The present invention relates to a device for enclosing the socket portion of a graphite electrode, and more specifically, the invention relates to a device for enclosing a socket portion of a graphite electrode, and more specifically, a device for enclosing a socket portion of a graphite electrode that heats metal, etc. by arc discharge in an electric furnace. In order to prevent the socket from being oxidized by flames and to prevent accidents such as breakage that may occur due to oxidation of the socket,
This invention relates to a device for enclosing a socket portion of a graphite electrode that covers an upper socket portion.

Conventional technology Electric furnaces have traditionally been used for refining iron, pig iron, etc., as well as non-ferrous metals and other metals in general. In particular, electric furnaces are used. Various types of electric furnaces are used depending on the purpose, and various types of electrodes for heating the metal are also used depending on the purpose, but the most common type is a graphite electrode. This type heats iron and other metals by arc discharge to melt and refine them. In this type of electric furnace, when a graphite electrode is consumed by refining, a new graphite electrode is connected one after another, and this connection is usually made by screwing a part of a graphite nipple into the upper socket of the electrode holder. This is done by threading the other part of the nipple into the lower socket part of the new graphite electrode.

In addition, recent electric furnace operation has become a high load, and the melting time has been shortened by using a combination of electrical heating and injection of heavy oil, etc. For this reason, flame is generated during refining, and this flame oxidizes and wears out the side surfaces of the electrode, and since it reaches the upper socket, the upper socket is also oxidized, and nipples etc. are inserted into this socket. When a new graphite electrode is connected through the wire, accidents at the connection point, such as nipple breakage, occur, which is a major operational hindrance.

That is, FIG. 2 is a cross-sectional view of a part of a conventional electric furnace, in which reference numeral 1 indicates a graphite electrode, 2 an electrode holder, 3 the ceiling of the electric furnace, and 4 a socket above the graphite electrode. At the time of connection, a nipple (not shown) is screwed into the socket part 4 as described above, and a new graphite electrode is connected via this nipple, but the upper socket part 4 is open during operation.
Therefore, when oxygen, heavy oil, etc. are blown into the electric furnace during high-load operation, and a large amount of flame is generated during operation, the flame 5 rises in the direction of the arrow, causing the electrode holder to The upper socket part 4 of the connector 2 is oxidized, which causes the strength of the connection part to deteriorate and accidents such as breakage to occur. For this reason, there is a need for a method and device for preventing oxidation of the socket part, which will prevent the upper socket part from being oxidized by flames even during high-load operations as described above. Currently, no technology has been proposed, and breakage accidents are occurring frequently.

Problems to be solved by the invention This invention aims to solve the above-mentioned drawbacks. Specifically, even in high-load electric furnace operation in which oxygen, heavy oil, etc. are injected, the flame generated during the operation It is an object of the present invention to propose an enclosing device that can protect a graphite electrode socket located at the upper part of a holder from being oxidized.

<Structure of the invention> Means for solving the problem and its operation That is, the device for enclosing the socket portion of a graphite electrode according to the present invention is provided with an enclosing cover that covers and surrounds the socket portion of the graphite electrode. This cover protects the socket from oxidation. In addition, an inert gas or non-oxidizing gas storage chamber is installed on the inner surface of the surrounding cover, and at least one through hole is formed in the wall surface of this storage chamber, and the inert gas or non-oxidizing gas is Since the gas is used to form a layer of inert gas or non-oxidizing gas between the surrounding cover and the housing chamber and the socket, the upper socket is always sealed with a non-oxidizing atmosphere. Since it is also cooled, it is completely protected from oxidation.

Therefore, the structure of these means and their operation will be explained in more detail with reference to FIG. 1 as follows.

First, FIG. 1 is a cross-sectional view of an enclosing device according to one embodiment of the present invention, and in particular, FIG. Indicates the condition. That is, the enclosing device 6 according to the present invention includes an enclosing cover 7, which covers and surrounds the upper socket portion 4 of the graphite electrode 1. The surrounding cover 7 is intended to protect the socket part 4 from oxidation caused by flames, and is designed to suit this purpose.
Any configuration is possible as long as the socket part 4 is covered and enclosed. The inner surface of the surrounding cover 7 is provided with a storage chamber 8 . This storage chamber 8 temporarily stores an inert gas and sprays the inert gas onto the threaded surface 4a of the socket portion 4 as described later.
protrude to the side. Further, in order to introduce an inert gas into the storage chamber 8, an introduction hole 9 is provided in the surrounding cover 7, and at least one through hole 10 is further formed in the wall surface of the surrounding cover 7. With this structure, the inert gas in the accommodation chamber 8 introduced from the introduction hole 9 is supplied between the accommodation chamber 8 and the threaded surface 4a of the socket portion 4 through the through hole 10, and there is a small amount of gas in between. A gap is formed, and an inert gas layer 11 is formed in this gap. More specifically, inert gas is introduced into the storage chamber 8 from the introduction hole 9 of the surrounding cover 7, and is temporarily stored in the storage chamber 8.

This inert gas flows from the through hole 10 into the socket portion 4.
An inert gas layer 1 is provided between the threaded surface 4a and the accommodation chamber 8.
1 and surrounds the socket part 4 with this layer 11. The inert gas in this layer 11 is dissipated in the direction of the arrow.

<Effects of the invention> As explained in detail above, the present invention includes an enveloping cover that surrounds the socket portion, a housing chamber for an inert gas or a non-oxidizing gas is provided on the inner surface of the enclosing cover, and air from this housing chamber is provided. Since it is made by injecting an inert gas or non-oxidizing gas onto the threaded surface of the socket, the socket above the graphite electrode is completely protected, and a large amount of flame cannot be generated by, for example, blowing oxygen. Even if a fire were to occur, the upper socket part would be completely protected from oxidation.

In other words, recent electric furnace operations are as described above.
In addition to simple electrical heating using graphite electrodes, oxygen injection or injection of heavy oil gas, etc., is often used in combination to shorten melting time. For this reason, a large amount of flame is generated during operation, and the upper socket section is damaged and oxidized by this flame, resulting in many accidents such as nipple breakage at the connection section, as described above. On this point, in the present invention, the upper socket part is surrounded by a surrounding cover and sealed by a flow of inert gas or non-oxidizing gas, so oxidation by flame can be completely prevented and non-oxidizing The upper socket is cooled by the flow of active gas or non-oxidizing gas.
Oxidation can be more completely prevented.

Note that nitrogen gas is usually preferred as the inert gas or non-oxidizing gas, but any inert gas that does not react with the graphite electrode, for example,
Argon and other gases can also be used.Furthermore, any non-oxidizing gas other than an inert gas can be used as long as it does not oxidize the graphite electrode, and non-oxidizing gases such as carbon dioxide can also be used. etc. can also be used.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an enclosure device according to an embodiment of the present invention, and FIG. 2 is a sectional view of a part of a conventional electric furnace. Code, 1...graphite electrode, 2...electrode holder, 3
...Ceiling of electric furnace, 4...Socket part, 4a...
Screw surface, 5...Flame, 6...Encircling device, 7...Encircling cover, 8...Accommodating chamber, 9...Introduction hole, 10...
Through hole, 11...Inert gas layer.

Claims (1)

[Scope of utility model registration request] A storage chamber for an inert gas or non-oxidizing gas is installed on the inner surface of the surrounding cover that covers and surrounds the socket portion of the graphite electrode so as to penetrate into the socket portion, and at least one gas is inserted through the wall surface of the storage chamber. two through holes are formed, and an inert gas or non-oxidizing gas from these through holes forms a layer of inert gas or non-oxidizing gas between the surrounding cover, the accommodation chamber, and the socket portion. 1. A device for enclosing a socket portion of a graphite electrode, characterized in that: