JPS6220436Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas blowing plug for blowing gas into molten metal in a container.

When gas is sent to the gas blowing plug, the gap between the refractory part and the metal case bottom iron plate and outer peripheral iron plate may open due to thermal expansion due to the gas pressure, resulting in a gas leak. As a result, there were problems such as not being able to secure a predetermined amount of gas and metal leakage from leakage parts. Gas blowing plugs are made with various structures, but some have a coating material applied around them as a measure to prevent leaks. However, in order to prevent the coating material from deteriorating, it must be packaged using a desiccant agent, and even if this method is used, it is not a perfect countermeasure.

In addition, the refractory part of the gas injection plug is surrounded by a metal case, and therefore it is unavoidable to prevent leakage between the refractory part and the metal case. The reason is that the bottom plate of the metal case is pushed downward by the gas pressure, which creates a gap between the bottom plate of the metal case and the refractory, which then spreads to the outer periphery of the metal case, causing leakage from the outer periphery.

As described above, currently no effective measures have been taken to prevent leakage between the metal case and the refractory. In addition, Utility Model No. 55-135041, Japanese Unexamined Patent Publication No. 1983-135041
Some models, such as 94182, have an iron plate that protrudes inward from the bottom plate of the metal case, but this is because the gas permeable body in the center of the plug body is surrounded by an outer refractory, and the gas permeable body directly protrudes inward. Since the bottom plate is fitted into the bottom iron plate, there is a risk of leakage occurring between the internally protruding iron plate and the gas permeable body, and the gas pressure in the cavity at the bottom of the gas permeable body acts to push down the bottom plate. At this time, since the internally protruding iron plate is simply fitted into the gas permeable body, the internally protruding iron plate moves downward. Therefore, the gap between the gas permeable body and the internal protruding iron plate is increased, and a gap is created between the lower part of the outer refractory and the bottom plate of the metal case, which leads to the generation of a gap in the outer circumference of the metal case. A leak will occur.

An object of the present invention is to provide a gas blowing plug structure that can solve the problems of the prior art described above.

The present invention consists of: (a) a gas permeable brick formed in the center; b) a gas impermeable brick surrounding the outer periphery of the gas permeable brick; d) an internally protruding iron plate having a proximal end fixed to the bottom iron plate and extending into the gas-impermeable brick; e)
This relates to a gas blowing plug consisting of a peripheral iron plate that surrounds the outer periphery of a gas-impermeable brick and has its base end fixed to a bottom iron plate.

In addition, the gas permeable brick referred to in this invention is
(1) Porous gas-permeable bricks made by adjusting the particle size of refractories, (2) Gas-permeable bricks with few pores, (3) Dense bricks with through holes, (4) A combination of dense bricks. Some use the joint gap as a gas permeation passage.

Further, the gas permeable brick may be divided into a plurality of bricks in the gas passage direction. There may be more than one internal protruding iron plate.

The present invention will be described in detail below with reference to embodiments shown in the accompanying drawings.

In FIG. 1, a gas-permeable brick 1 is shown as a solid truncated cone, and gas-impermeable bricks 2 forming a hollow truncated cone are concentrically surrounding the outer periphery of the gas-permeable brick 1. There is. Gas impermeable brick 2
is preferably formed by casting, but may also be formed by other molding methods. 3 A bottom iron plate attached to the bottom surfaces of the gas-permeable brick 1 and the gas-impermeable brick 2 in a bonded state, and the bottom iron plate 3 has a gas introduction pipe 4 extending downward protruding from approximately the center thereof. There is. The base end of an annular outer iron plate 5 is integrally fixed to the outer peripheral edge of the bottom iron plate 3, and the outer peripheral iron plate 5 covers at least the lower outer peripheral surface of the gas-impermeable brick 2 with its inner peripheral surface. Supports joints. Furthermore, 6 is an annular internally protruding bottom plate, and the internally protruding bottom plate 6 has its base end fixed to the upper surface of the bottom iron plate 3, and extends into the gas-impermeable brick 2 and is strongly connected to the brick 2. There is.

In the above configuration, it is preferable that the internal protruding iron plate 6 is spaced 10 mm or more from both the inner and outer circumferential surfaces of the gas-impermeable brick 2 to prevent cracks. In order to prevent cracks from appearing in the direction perpendicular to the gas passage direction from the upper end portion (near) of the outer peripheral iron plate 5, the extended end of the internally protruding iron plate 6 is made to differ in height by at least 7 mm from the extended end of the outer peripheral iron plate 5. is preferred. In order to further ensure sufficient bonding, the protrusion height of the internal protruding iron plate 6 into the gas-impermeable brick 2 is 10 mm.
It is preferable to set it as above.

Another embodiment is shown in FIG. 2, and this embodiment is characterized in that the gas permeable brick 1 has a required number of through holes 7.

Next, the operation of the gas blowing plug having the above configuration will be described. For example, the gas introduction pipe 4 is attached to the bottom of the molten metal container and supplies gas such as argon.
Assume that the gas flows into the molten metal through the gas-permeable brick 1. In this case, the gas that has flowed into the plug generates a force that tries to separate the bottom iron plate 3 from the gas permeable bricks 1 and the gas impermeable bricks 2 due to its gas pressure, but the internal protruding iron plate 6
extends into the gas-impermeable brick 2 and provides a sufficient bond between the two, so that separation can be completely prevented, thereby blocking gas leakage.

As described above, the gas blowing plug according to the present invention has the following effects.

(1) The internally protruding iron plate ensures a sufficient bond between the bottom of the gas-impermeable and gas-permeable bricks and the bottom iron plate, so gas leakage can be completely prevented.

(2) Since the heights of the extension ends of the internal protruding steel plate and the outer peripheral steel plate are made different, the occurrence of cracks can be completely prevented.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional front view of one embodiment of a gas blowing plug according to the present invention, and FIG. 2 is a cross-sectional front view of another embodiment. In the figure, 1... gas permeable brick, 2... gas impermeable brick, 3... bottom iron plate, 4... gas introduction pipe, 5... outer circumferential iron plate, 6... internal protruding iron plate,
7...Through hole.

Claims (1)

[Scope of Claim for Utility Model Registration] (a) A gas-permeable brick formed in the center; (b) A gas-impermeable brick surrounding the outer periphery of the gas-permeable brick; (c) A gas-impermeable brick that is attached to the bottom of both of the above bricks, a bottom iron plate having an inlet pipe; d) an internal protruding iron plate whose base end is fixed to the bottom iron plate and extends into the gas-impermeable brick; A gas blowing plug consisting of an outer steel plate fixed to a bottom steel plate.