JPS5938431Y2 - porous plug - Google Patents

Description

[Detailed explanation of the invention] The invention consists of 1) equalizing the temperature by stirring the hot metal and molten steel;
) Removal of non-metallic inclusions in molten steel; and 3) Degassing of hydrogen, oxygen, etc. in molten steel.

Porous blocks are generally used to manufacture the above-mentioned porous plugs, but they have problems with durability.
Therefore, in recent years, a dense block with through holes has been developed and is now used in actual operations.

However, the conventional through-hole type porous plug has a problem in terms of the accuracy of the hole diameter of the through-hole (the smaller the hole diameter and the longer the length of the plug, the more the problem becomes).

), and those made dense and provided with through holes had poor spalling resistance and also had problems in air permeability.

The present invention was devised in consideration of the current situation, and its purpose is 1) to provide a through-hole type porous plug that can improve the accuracy of the through-hole diameter and improve air permeability and spalling performance. That is.

The present invention relates to a porous plug characterized in that a plurality of porous plug segmented pieces are each provided with a through hole extending in the axial direction, and the porous plug segmented pieces are combined in a stepped layered manner.

In the above structure, the porous plug piece is molded from a dense refractory, but such a dense refractory may be one or two of corundum, mullite, magnesia, macnesia chrome, zircon, zirconia, spinel, carbon, clay, etc. Combinations of more than one species are possible.

Furthermore, an air layer may be provided between each porous plug segment as a heat insulating layer or for breathability.

Next, the porous plug according to the present invention will be specifically explained with reference to embodiments shown in FIGS. 1 and 2.

In the embodiment shown in FIG. 1, the porous plug 1 has an upper and a lower porous plug segment 1 having a truncated conical shape.
It is formed by combining a and 1b in a step-layered manner.

Each porous plug 1a and 1b is provided with a through hole 2ay2b extending in the axial direction.

The through hole may be formed by, for example, firing a buried metal wire and then pulling it out, or kneading an oriented combustible material into a dense refractory and then firing it.

Further, the number of through holes is determined based on the hole diameter and the amount of ventilation.

The porous plug 1 having the above-described configuration is integrated with a protective iron shell using mortar or the like 3 as shown in FIG.

FIG. 2 shows another embodiment of the posisprag according to the present invention, which essentially consists of an inner columnar body 5 and an outer cylinder body 6. As shown in FIG.

The inner columnar body 5 is constructed by combining upper, middle, and lower porous plug segments 5 a +5 b and 5 c in a step-layered manner.

Further, each of the divided pieces 5a, 5b, and 5c is provided with a through hole 6ay6bt6c extending in the axial direction.

The method and number of through holes are the same as in the first embodiment.

In this embodiment, air layers 7a, 7b are further provided between the divided pieces 5a, 5b, 5c.

In the molding of the porous plug according to this embodiment, the outer cylindrical body 6 is molded by pouring, thus eliminating the need for mortar.

However, the first embodiment can also be molded using mortar, or can also be molded by stamping or the like.

Next, the operation of the porous plug according to the present invention will be described (described with particular reference to the first embodiment).

A gas such as argon is blown into the through hole 2b of the porous plug 1 in the same way as a conventional porous plug.

The blown gas first flows through the through hole 2b, and then passes through the divided pieces 1a,
lb comes into contact with the surface.

In this case, the through holes 2b and 2a are in a misaligned state with each other (although this is not the case, it is also possible to have portions of the through holes that are aligned with each other).

) Gas flows from the through holes 2b to 2a along the gaps therebetween or the pores present in the divided pieces 1b, 1a, and then flows into the molten metal through the through holes 2a.

Note that the above gas flow is similar to that of the air layers 7a and 7b of the second embodiment.
This can be further promoted by providing

As described above, the porous flag according to the present invention has the following effects.

(1) Since it is a multi-stage type and has a through-hole type, it is compact, and the through-hole can be formed with high precision, and the parts other than the through-hole can be made denser and more homogeneous (no variation). Corrosion resistance can be improved.

In particular, the corrosion resistance of the upper layer segment can be improved, which is highly effective.

(2) By making the through holes in each stage misaligned in the axial direction, safety against penetration of molten metal can be further increased.

(3) By creating a fault or air layer in the middle,
Temperature gradients are relaxed, and despite being dense, spalling resistance can be improved, leading to improved breathability.

(4) In a multi-stage structure, the number of holes can be varied to accommodate changes in air permeability during the process of erosion.

(5) The material of each stage can be varied.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional front view of a first embodiment of a porous plug according to the present invention, and FIG. 2 is a cross-sectional front view of a second embodiment.

Claims (1)

[Scope of utility model registration request] A porous plug characterized in that a plurality of porous plug segment pieces are each provided with a through hole extending in the axial direction, and the porous plug segment pieces are combined in a stepped layered manner.