JPH065372Y2 - Anomaly detector for graphitization furnace - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to an abnormality detection device for a graphitization furnace used for the production of various graphite products.

[Conventional technology]

In the graphitization furnace, as shown in FIG. 2, a box-shaped furnace body 2 made of refractory bricks having terminal electrodes 1 fixed at both ends is filled with a firing material (graphitized product) 3, and the periphery thereof is packed with coke 4
Also, it has a structure in which it is encapsulated by a heat shield lining layer 5 such as silica sand and a mixture of coke. The terminal electrode 1 is usually composed of a graphite cylinder, and is fixed through a hole formed in the furnace wall with a refractory mortar so that the head projects into the furnace, and the outer end of the furnace is connected to the bus bar 6. ing. During operation, electricity is supplied from the terminal electrode 1 through the bus bar 6 in the longitudinal direction of the furnace, and resistance heating causes 2500
Keep in the high temperature range of ~ 3000 ℃.

[Problems to be solved by the invention]

In the above graphitization furnace, the terminal electrode may be damaged by severe thermal stress, or may be cracked in the joint layer of the refractory mortar so that the outside air may enter and the terminal electrode may be locally oxidized and consumed.

When such a situation occurs, abnormal heat is generated around the terminal electrode to melt and damage the furnace material, and in some cases, a large accident such as red hot packing coke jetting out of the furnace is induced.

[Means for solving problems]

This invention provides an apparatus for detecting an abnormal phenomenon of the above-mentioned graphitization furnace in advance to prevent an operational accident.

That is, the graphitization furnace abnormality detection device according to the present invention is
A structural feature is that a thermocouple is embedded along the axial direction of the terminal electrode in a joint layer of a refractory mortar material that fixes the outer peripheral surface of the terminal electrode to the hole in the furnace wall.

[Action]

As a refractory brick for constructing a furnace body of a graphitization furnace, one having a fire resistance of around JIS-SK No. 32 is usually used.
It does not melt at temperatures below 00 ° C. The temperature on the inner surface of the furnace wall during operation does not exceed 1000 ° C.

Therefore, when the joint layer portion of the refractory mortar material for fixing the terminal electrode is heated to 1000 ° C. or higher, it is a precursor of abnormal heat generation in the furnace.

In this invention, the thermocouple buried in the refractory mortar joint layer is 1
By using a wire made of a combination of wires having a melting point of 000 ° C or higher, it can be detected that the temperature rises abnormally when the lateral temperature exceeds 1000 ° C, and the melting point of the thermocouple-constituting wires. When the strands are blown by the heat over the temperature, the side temperature becomes impossible due to the interruption of the thermoelectromotive force, and it is possible to know the occurrence of an abnormal phenomenon in the terminal electrode or in the furnace.

〔Example〕

 The present invention will be described below based on the illustrated embodiment.

FIG. 1 is an enlarged plan sectional view showing a furnace wall portion to which a terminal electrode is fixed. In the drawing, 1 is a terminal electrode, 7 is a furnace wall, 8 is a thermocouple, and 4 is coke packing filled in the furnace. , 6 are bus bars connected to the outer end of the furnace of the terminal electrode 1. The terminal electrode 1 has its outer peripheral surface penetratingly fixed to the furnace wall hole through a refractory mortar material so that both end portions project into and out of the furnace, and an insulating mesh is provided between the outer peripheral surface of the terminal electrode and the inner surface of the furnace wall hole. Formation 9 is formed.

The usable temperature of the thermocouple 8 is determined according to the type of constituent wire. Platinum rhodium-platinum (PR) is 1600 ° C, chromel-alumel (CA) is 1200 ° C, iron-constantan (IC).
Is 800 ° C, and copper-constantan (CC) is 350 ° C.

Therefore, for the purpose of the present invention, platinum rhodium-platinum and / or chromel-alumel is preferable among the thermocouples.

The thermocouple 8 has a temperature measuring contact 10 to which one end of two kinds of metal wires are connected as a tip, and is inserted into a protective tube 12 preferably through an insulating tube 11 so as to fix the terminal electrode 1 to the base end portion 1.
In a state where 3 and 14 are drawn out of the furnace, they are embedded in the joint layer 9 of the refractory mortar material along the axial direction of the terminal electrode 1. The embedding shape of the thermocouple 8 can be appropriately designed such that one or a plurality of thermocouples can be laid around the terminal electrode 1 as shown in FIG.

The base end portions 13 and 14 of the thermocouple 8 drawn out of the furnace are connected to a measuring instrument directly through a conductor (not shown) to detect an abnormality by temperature measurement, and / or to control energization in conjunction with a power transmission device. Systemize.

[Effect of device]

Since the graphitization furnace abnormality detection apparatus according to the present invention has the above-described structure and mechanism, when abnormal heat is generated around the terminal electrode and the joint layer temperature rises above 1000 ° C., an abnormal situation is caused by the measured temperature. It can be detected and appropriate action can be taken. Therefore, major accidents such as melting damage of the furnace material and jetting of red-hot packing outside the furnace are prevented in advance, and a safe and smooth graphitization operation is always guaranteed.

[Brief description of drawings]

FIG. 1 is a plan sectional view showing an embodiment of the present invention. FIG. 2 is a perspective explanatory view showing an overall image of the graphitization furnace. 1 ... Terminal electrode, 2 ... Furnace body, 3 ... Baking material (graphitized product), 4 ... Packing coke, 5 ... Heat shield lining layer, 6 ... Bus bar, 7 ... Furnace wall, 8 …
… Thermocouple, 9… Joint layer, 10… Temperature measuring contact, 11…
Insulation pipe, 12 ... Protection pipe, 13,14 ... Thermocouple base end.

Claims (1)

[Scope of utility model registration request] 1. An abnormality detecting device for a graphitization furnace in which a thermocouple is embedded along the axial direction of the terminal electrode in a joint layer of a refractory mortar material for fixing the outer peripheral surface of the terminal electrode to a furnace wall hole.