JPS6076259A - Method for opening hole to closed part of outflow hole for molten metal - Google Patents

Abstract

PURPOSE:To open safely and easily a hole in the closed part of an outflow hole by disposing an ejection pipe of an ejection mechanism mounted to the prescribed nozzle of a sliding nozzle device into a flow passage for a molten metal, directing the ejection port of said pipe to the closed part and an injecting gas thereto. CONSTITUTION:An injection mechanism having an ejection pipe 5 disposed in a flow passage A for a molten metal is provided to a lower nozzle 1 fitted to a lower plate 9 of a sliding nozzle device and the ejection port at the top end of the pipe 5 is positioned near the sliding surface of an upper plate 10, then a long nozzle 15 is mounted to a lower nozzle 1 fitted to a lower plate 9 of a sliding nozzle device when the outflow port for the molten metal is closed in the initial period of pouring the molten by a sliding nozzle method. The plate 9 is then slided to open and the packing 14 which is not sintered is dropped. Oxygen, acetylene or the like is ejected from the pipe 5 toward the sintered layer 13 remaining near the bottom 12 of the vessel for the molten metal from a nozzle 11 to inject the flame to the layer 13, thereby melting instantaneously said layer and opening the hole.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a sliding nozzle device (hereinafter referred to as an SN device including a reciprocating type and a rotary set) for a container for molten metal such as a ladle or a kundishu (hereinafter referred to as a molten metal container). The present invention relates to a method for opening a blocked portion of an outflow hole.

[Technical background]

Currently, in steel casting, molten metal vessels equipped with SN devices are commonly used. The plate bricks of this SN device are closed to receive the molten metal, but accidents have occurred in which the molten metal solidifies in the flow holes of the upper plate brick, making it impossible to discharge the molten metal. Therefore, as a means to prevent accidents, a method has been adopted in which various fillers are inserted into the outflow hole from the upper nozzle to the upper plate. However, the part of this filler that comes into contact with the molten metal is sintered to form a shell, and there are many cases where the molten metal cannot flow out even if the plate brick is opened. Therefore, in order to melt the sintered part,
BACKGROUND OF THE INVENTION Outlet hole cleaning methods and devices disclosed in Japanese Utility Model Publication No. 11832, Japanese Utility Model Application Publication No. 55-49819, and the like are known. However, these methods and devices still have some problems. For example, in both cases, the cleaning pipe is inserted from the outlet of the lower nozzle, but the worker must insert and hold the pipe while supporting it with his/her hands, and depending on the conditions of the workplace, the cleaning pipe may not be inserted properly. It can be time consuming. Moreover, it is hard work in hot conditions, and the work is extremely dangerous, as there is a risk of the molten metal flying away when the molten metal is discharged immediately after the hole is opened. Furthermore, it is now common to use a long nozzle (or submerged nozzle) below the lower nozzle to prevent oxidation of the molten metal, so when using a conventional cleaning pipe, it is necessary to wait until the molten metal begins to flow out. However, long nozzles and the like could not be fitted, making the work process complicated and forcing dangerous work under hot conditions, resulting in various problems in terms of the environment, safety, workability, steel quality, etc.

[Purpose of the invention]

The present invention eliminates the need for workers to do hard labor while being exposed to high heat and danger, and even when using a long nozzle, it is possible to eliminate the dangerous and complicated work of fitting the lower nozzle after drilling the hole. It is an object of the present invention to provide a method for opening a closed portion of a molten metal outflow hole.

[Structure of the invention]

In the present invention, the injection pipe of the injection mechanism provided in the lower nozzle or the like is configured to direct the ejection port toward the blockage within the molten metal flow path, and inject gas or flame to open the blockage.

Further, in the present invention, such a hole is formed while preventing the reverse flow of the molten metal.

〔Example〕

The present invention will be specifically explained below using a preferred example of a lower nozzle according to embodiments shown in the accompanying drawings.

FIG. 1 is a sectional view of a lower nozzle (1) having a closed hole opening mechanism according to the present invention, and the lower nozzle is connected to a connecting pipe (3).
), this is an example in which an injection mechanism (4) consisting of an ejection pipe (5) is provided. The lower nozzle (11) has a through hole (2) in its lower part, and a connecting pipe (3) is fitted into the through hole (2).The connecting pipe (3) has its insertion end (3a ) is bored with a slot (6) into which the lower end of a gas jet pipe (5) having a jet port (5a) extending inside the molten metal flow passage (A) of the lower nozzle (1) is fitted. The tip of the connecting tube (3) is closed.The groove (6) and the lower end of the gas ejection tube (5) are fitted together by a hood.Also, the outer end of the connecting tube (3) The part forms a fitting part (7) widened to be threadedly connected to the gas supply connecting pipe (8).
) can prevent the connecting pipe (3) from entering.

The connecting pipe (3) is not limited to a circular cross section, but may have a rectangular cross section or even a polygonal cross section, and fitting into the through hole (2) is performed using mortar,
Fix it tightly with asbestos, etc. Injection mechanism in diagram (4)
Although shown as an assembled type, it may also be a single piece that is integrally molded during molding of the lower nozzle.

A practical example of the present invention is shown in FIG. 2, FIG. 5, and FIG. 3.

In Figure 2, the lower nozzle (1) is connected to the lower plate (9).
), the tip of the gas ejection pipe (5) extends to a position where it reaches the sliding surface of the upper plate α0). When the lower plate (9) slides open, the unsintered filling (
14) falls, leaving a sintered layer (13) from the upper nozzle (11) near the bottom (12) of the molten metal container. This sintered layer (1
3) Oxygen, acetylene and mixtures thereof, etc.
The sintered layer (13) is immediately dissolved and opened by ejecting other combustion-assisting or combustible gases singly or in combination. There are various methods of early melting by igniting the sintered layer (13) or igniting combustible gas, but using nail scrap alone or in a mixture with a combustible material (for example, a solid carbon source such as the product name Carbone Nodo) as the filling. if you did this,
The sintered layer (i3) is hot enough to turn red, and can be easily ignited or ignited to melt and open the pores, and unlike the case of using refractory sand, contamination of the molten metal can be prevented. In addition, a long nozzle (15
) can be drilled with the long nozzle (
15) can be omitted, and oxidation of the molten metal due to air entrainment can be minimized.

Third. FIG. 4 shows a multistage structure of the gas ejection pipe (5) of the lower nozzle (1). As shown in Figure 2, from the position of the lower plate (9), it is necessary to eject gas at a fairly high pressure to the sintered layer (13) to melt it. ) can be solved by constricting the tip outlet (5a). Third. Figure 4 shows an attempt to further increase the ejection effect of the gas ejection pipe (5), and the tip of the upper extension part (5'') of the gas ejection pipe reaches close to the sintered layer (13), making it easy to sinter. The condensation (13) can be melted.In other words, when the lower plate (9) is in the closed state, the upper extension part (5'') of the gas jet pipe is compressed by the spring (16) and stored in the flow hole. cage, lower plate (
When the hole 9) slides open, it extends upward by the restoring force of the spring (16). The elastic force of the spring should be strong enough to push and hold the gas ejection tube upper extension part (5'') up to the upper end of the gas ejection tube base pipe part (5').

The upper extension part (5'') of the gas ejection pipe is the base pipe part (5') of the gas ejection pipe.
is fitted inside it, and the lower end is concentrically connected with a flange part (5') slightly larger than the outer circumference of the gas ejection pipe base pipe part (5').
17). On the other hand, the base pipe part (5') of the gas ejection pipe
The tip of the flange portion (18) protrudes from the outer periphery to the extent that it comes into contact with the inner wall of the gas ejection pipe upper extension (5″).This prevents the gas ejection pipe upper extension (5″) from coming off. . In the case of three-stage expansion/contraction, a flange, a spring, etc. may be provided on the outside of the upper extension part (5'') of the gas ejection pipe, and a second upper extension part may be further provided. Although a single plate type is shown, the present invention is not limited to this, and for example, a three plate type may also be used.

Figures 5a and 5b show an example in which a molten metal backflow prevention mechanism is provided, and Figure 5a shows an example in which the molten metal solidification part (19) is connected to the connecting pipe (3) and runs around the lower nozzle. It is easy to cool and solidify if the material has good thermal conductivity, such as iron or steel pipes, but the backflow prevention effect can be obtained even if the material is made of iron or steel pipe.

FIG. 5b shows an example in which the molten metal solidification part has a spiral shape (19'). Other examples include interposing an iron rod pipe in the connecting pipe (3), and using a mechanism that allows the gas supply to the gas supply connecting pipe (8) to be switched to an inert gas such as argon or nitrogen as soon as the molten metal outlet hole is opened. But it's okay. By doing this, i
It is possible to prevent molten metal from flowing back, or vice versa, to prevent oxidation of the molten metal due to air being drawn in from the connecting pipe (3).

〔Effect of the invention〕

According to the present invention, the following effects can be obtained.

■ Workers do not have to risk getting close to containers filled with molten metal.

■ There is no need to hold a long and heavy cleaning tube and insert it from the lower outlet of the lower nozzle, making hole opening work easier.

■ Since the long nozzle (or immersion nozzle) can be used with it attached to the lower nozzle, there is no need to do the dangerous work of hastily fitting the long nozzle after opening the blockage.

■ Immediate hole opening can be performed easily and reliably.

■ It also has the effect of preventing air from entering and preventing molten metal from oxidizing.
It is also useful for improving the quality of steel products.

■ By using nail scrap alone or in combination with combustible materials as a filling, there is no contamination of the molten metal due to the mixing of fillers such as refractory materials, and clean steel products can be obtained, contributing to the production of high-grade steel.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the lower nozzle according to the present invention, Fig. 2 is an example of the use of the lower nozzle, Fig. 3 is an explanatory diagram of the usage state of an embodiment of the gas ejection pipe of the lower nozzle with another shape, and Fig. 4 is an illustration of the usage state of the lower nozzle. The enlarged view, FIG. 5a, and FIG. 5b are explanatory diagrams of an embodiment having a molten metal backflow prevention mechanism. In the figure, (A) Molten metal flow path (11 lower nozzle (2) through hole (3) connecting pipe (3a) connecting pipe insertion end (4) injection mechanism (5) gas jet pipe (5a) jet port (5') ) Gas ejection pipe base pipe (5″) Gas ejection pipe upper extension pipe (6) Slot (7), outer end (8) Gas supply connecting pipe (9) Lower plate QOI Upper plate (11) Upper nozzle ( 12) Bottom of molten metal container (13) Sintered layer (14) Filler (15) Long nozzle (or immersion nozzle) (16) Spring (17), (18) Stopper flange (19),
(19”) Molten metal solidification section Fig. 1 Fig. 3 Fig. 2 Fig. 4 Fig. 50 Fig. 5b

Claims (1)

[Scope of Claims] 1. In a hole-opening method that is performed when a molten metal outlet blockage occurs during the initial stage of pouring molten metal using a sliding nozzle system, the molten metal is passed through the jetting pipe of the jetting mechanism provided at a predetermined nozzle of the sliding nozzle device. 1. A method for opening a closed part of a molten metal outlet hole, characterized in that a gas or flame is injected into the channel by directing the jet outlet toward the closed part. 2. The method for opening a closed portion of a molten metal outlet hole according to claim 1, wherein the jetting pipe of the jetting mechanism is a multi-stage telescopic pipe. 3. The method for opening a hole in a molten metal flow mountain top blockage portion according to claim 1, wherein the injection mechanism has a molten metal backflow prevention mechanism.