JPS6191312A - Operating method of ladle refining furnace - Google Patents

Abstract

PURPOSE:To facilitate the repair operation for refractories after the end of refining and to extend the service life of a water cooling cap by spraying thinly castable refractories to the inside of the water cooling cap of a ladle refining furnace without providing studs. CONSTITUTION:The castable refractory layer 13 consisting of 60% Al2O3 and 40% SiO2 is formed by spraying to 5-30mm thickness on the inside surface of a shell 12 of the water cooling cap 11 of the ladle refining furnace for a molten steel. Since the layer 13 is thin, the cooling effect of the water cooling cap is improved. Said layer is easily stripped and removed and the fresh layer 13 is sprayed after the end of one refining. Since there are not studs, the stripping operation of the layer 13 is extremely simple and the water cooling cap which withstands long-term use without cracking of the refractory layer as a result of partial melting or the melting and failure of the shell 12 from the crack is obtd.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention provides a method for operating a ladle refining furnace with an improved water-cooled lid;
Regarding [Prior Art] The water-cooled lid of a ladle smelting furnace usually has a large number of studs 2 protruding from the inner surface of the iron shell 1, as shown in Fig.
A castagle refractory layer of about 0.0 mm is formed.

Further, the outer surface of the iron skin 1 has a water-cooled structure.

[Technical Problem to be Solved by the Invention] However, in the water-cooled lid 4 having this structure, the base metal 5 adheres to the #1 metal pull refractory layer 3 due to melting, cracking, etc. Although the attached base metal 5 is peeled off after completion of refining, the base metal 6 may have penetrated into the inside of the castable refractory layer 3. For this reason, when cutting the bare metal, the steel shell 1 is cut and water leakage accidents occur.In this case, the steel shell 1 must be repaired and welded, and the water cooling cover itself must be replaced, making the repair work time-consuming. There was a drawback that the life of the water cooling lid was short.

The present invention has been made in view of the above circumstances, and its purpose is to provide a method for operating a ladle smelting furnace that allows for easy repair work after the completion of smelting, and that allows the water-cooled lid to be used for a long period of time. That is.

[Structure of the invention]

The present invention constructs a water-cooled lid by spraying a refractory on the inner surface of the steel skin of the water-cooled lid (no studs are protruding) to form a coating layer with a thickness of 5 to 30 m, preferably 5 to 10 m. However, when operating a ladle smelting furnace using this water-cooled lid,
This is a method of operating a ladle refining furnace in which after each refining process, all used coating layers are removed and a new coating layer is sprayed.

〔Example〕

The present invention will be described below with reference to illustrative embodiments.

FIG. 1 shows a water-cooled lid according to the invention. This water-cooled lid 11 is made by spraying a refractory material on the inner surface of the iron shell 12 of the cooling structure (no studs are protruded here) and coating a coating layer 13 with a thickness of 5 to 30 m+, preferably 5 to 10 m. is forming. The material of the large resistant material used here is a refractory material suitable for ordinary spraying, such as At20. Weight 60% and Si
It has a composition of 40% by weight of 02. The reason why the thickness of the coating layer 13 is limited to the above range is that if the thickness is less than 5, the thickness is insufficient and cannot function as a refractory, and if it exceeds 301, the cooling performance will decrease. It is.

In the pot invention, the water-cooled lid 11 is used to operate the ladle refining furnace, but when one refining process is completed, the coating layer 13 is completely peeled off and a new coating layer 13 is formed by spraying. Refining.

According to this method, since the coating layer 13 is relatively thin, cooling performance is good and base metal is less likely to adhere. Even if hazardous gold adheres, the coating layer 13 is unlikely to melt or crack due to its good cooling properties, so when the coating layer 13 is peeled off, it will not affect the iron skin. Furthermore, since there is no "stat", it is easier to peel off the coating layer 13.
Easy to use, improves work efficiency. [Effects of the Invention] As explained above, according to the present invention, there is no risk of cutting the steel skin when cutting the bare metal, the water cooling lid can have a long life, and since there is no stud, peeling of the coating layer is prevented. Extremely easy to work with.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of a water-cooled lid used in the operating method of the present invention, and FIG. 2 is a sectional view of a water-cooled lid used in a conventional operating method. l...9 leather, 2...stat, 3...caster and other person-resistant layers, 4...water cooling lid, 5...base metal, 11...
・Water cooling lid, 12...iron skin, 13...coating layer. Applicant's agent Patent attorney Takehiko Suzue Figure 2 Cause

Claims (1)

[Claims] A water-cooled lid is constructed by spraying refractory on the inner surface of the steel skin without studs to form a coating layer with a thickness of 5 to 30 mm, and when operating a ladle smelting furnace using this water-cooled lid, A method of operating a ladle smelting furnace in which all used coating layers are peeled off and a new coating layer is sprayed after each smelting process.