JPS60197809A - Sealing device between converter port and skirt of converter waste gas treating device - Google Patents

Abstract

PURPOSE:To seal thoroughly the port and skirt of a converter by pressing the port into the skirt by a water-cooled sealing ring provided in the lower part of the skirt and breaking the slag sticking to the port by the press-contact force and the thermal impact by cooling. CONSTITUTION:A sealing ring 17 having a hollow part 18 is provided to an annular frame 19 holding a skirt 2 and a sealing jacket 22 is provided to the frame 19 and is connected to a cylinder 21 via a bracket 20. The ring 17 is constituted of a heat-resisting cast iron into a circular sectional shape and cooling water is passed in the hollow part 18 thereof. The ring 17 is pressed to the port 12 of a converter by the cylinder 21 in the stage of hermetic sealing during refining. The slag sticking to the port 12 is cracked by the pressing force developed in this stage and by the thermal impact resulting from cooling of the ring 17, by which the port 12 and the skirt 2 are brought into tight contact with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a sealing device that can more completely seal between the furnace mouth and the skirt of a converter exhaust gas treatment device.

[Background of the invention]

First, the outline of the converter exhaust gas treatment apparatus will be explained using FIG. 1. In the figure, pure oxygen is blown into hot metal in a converter 1 through an oxygen injection lance 11 to refine it (hereinafter referred to as blowing). During this blowing, a large plate of CO gas is generated.

This CO gas is removed by induced air 1rfA7.
After being cooled by the hood 3 and the cooler 4, the gas is removed by the dust collectors 5 and 6, and collected as valuable gas in the gas holder 9.

Also, the exhaust gas with low CO concentration at the beginning and end of the blowing is radiated through the chimney 8 by switching the damper 10.

In the above series of processes, the skirt 2 is important in performing the following functions.

In other words, converter operation consists of a receiving process in which hot metal produced in a blast furnace is received by tilting the converter, and a converter exhaust gas treatment equipment in which a skirt seals the space between the converter mouth and the hood. The skirt 3 seals between the converter mouth and the hood during the refining process and prevents CO gas from leaking to the outside.
The skirt is moved upward to enable tilting of the converter, and at the time of refining, the skirt 2 is lowered to seal the space between the converter mouth and the hood 3.

Recently, in order to limit the intrusion of outside air as much as possible and obtain high-purity CO gas, there has been a trend to increase the pressure inside the equipment to a level higher than atmospheric pressure. Therefore, more and more perfect seals are now required.

A conventional seal between the converter mouth and the skirt is shown in FIG. In the figure, 1 is a converter, 2 is a skirt, and the lower end of the skirt 2 is formed to match the shape of the converter mouth.
I tried to seal it by surface contact. Note that 17 in the figure
When the skirt 2 is moved up and down by the skirt cylinder 19 suspended from the floor 20, the lower end of the seal cylinder 18 is immersed in the water filling the seal part 17. By this, the space between the skirt 2 and the hood 3 is sealed with water.

In this conventional sealing device, the slag that adheres to the furnace mouth of the converter 1 is not uniform, but is irregularly adhered with a formable uneven surface. The target strength was low, and it was not possible to crimp with a strong enough force.

As a result, a large gap was created between the furnace mouth and the skirt 2, and a complete seal could not be achieved.

As an improved version of this, Fig.
No. 1) is disclosed.

This sealing device has a water-cooled partition wall 13 on the outer periphery of the skirt 2.
A seal ring 15 is further provided on the outside thereof, and a flexible member 14 provides a seal between these rings. This sealing device uses a water-cooled partition wall 13 to block slag 16 that accumulates at the furnace mouth 12 during refining, and a seal ring 15 to completely seal between the furnace mouth and the skirt 2.

However, in the conventional sealing device described above, since the seal ring 15 is ring-shaped, the formation of heat at the furnace port 12 is caused by manufacturing errors in the furnace port 12 and the seal ring 15, so that both of them are completely separated. It is extremely difficult to get them in close contact, resulting in gaps.

Furthermore, even if an elastic body is used for the seal ring 15 to prevent sealing between the two due to thermal deformation of the furnace mouth or manufacturing errors, the furnace mouth 12 is at a high temperature, so the seal ring 15 deteriorates.
The disadvantage is that it has a short lifespan.

In addition, this conventional sealing device does not actively seal the water-cooled partition wall 13 and the skirt 2, but only seals the seal ring 15.
Since the above-mentioned gap between the furnace opening 12 and the seal ring 15 and the life of the seal ring 15 ultimately depend on the function and life of the entire sealing device, the function of the skirt currently required The reality is that this is not always satisfactory.

[Purpose of the invention]

The present invention has been made in view of the above circumstances.

[Summary of the invention]

That is, the present invention is designed to actively crush the slag and seal it, instead of avoiding sealing at the part where the slag is attached or sealing with an elastic body as in the past. A seal ring with a circular cross section made of heat-resistant cast iron is provided at the bottom, and this seal ring is made hollow. Cooling water is circulated through this hollow part to cool the seal ring, and this cooling causes thermal shock and crimping of the skirt cylinder. The feature is that the slag is crushed by force and the space between the skirt and the furnace mouth is sealed.

The second invention provides a seal ring molded from heat-resistant cast iron at the bottom of the skirt, and forms the contact surface between the seal ring and the outer circumferential surface of the furnace mouth into a sawtooth shape, and cools it with water, and the thermal shock of this water cooling. It is characterized in that the seal is destroyed by the compression force of the skirt cylinder and the sealing between the furnace mouth and the skirt is actively performed.

[Embodiments of the invention]

An embodiment of the present invention will be described in detail below. &'
! In FIG. 4, a seal ring 17 is attached to an annular frame 19 holding the skirt 2, and is attached to the lower part of the skirt 2 so as to be in contact with the furnace opening 12. This seal ring 17 is made of heat-resistant cast iron and has a circular cross-section, and has a hollow part 18 formed in the center thereof to allow cooling water to flow therethrough. 20 is a bracket fixed to the annular seven frame 19, and this bracket 20 has a skirt cylinder 2 for raising and lowering the skirt 2.
1 are connected. In addition, 22 is a seal jacket,
3 is a hood.

Regarding the operation of this embodiment configured as described above, the skirt 2
At the same time, the seal ring 17 moves up and down. At the time of sealing during refining, the pressing force of the skirt cylinder 21 is directly transmitted to the seal ring 17 via the bracket 20 and the annular frame 19. On the other hand, since the seal ring 17 is being cooled, the high-temperature slag adhering to the furnace mouth of the converter 12 is rapidly cooled, and the slag generates cracks and is thermally destroyed by the thermal shock caused by this rapid cooling. Also seal ring 1
7 has a circular cross section, so the contact between the unevenly adhered slag and the seal ring 11 is close to point contact, and the pressing force of the skirt cylinder 21 is a large force. Crush the slag.

In this way, when the skirt cylinder 21 is pressed, the slag is crushed due to the interaction of force, thermal shock, and point contact between the seal ring 17 and the slag, and the unevenness of the slag is removed from the seal ring 1.
7, and is sealed between the seal ring 17 and the slag while applying pressure.

Alternatively, depending on the state of the slag adhesion, the slag may be peeled off from the furnace mouth of the converter 12 due to the mutual effect of thermal shock and compression force, and the furnace mouth and the seal ring 17 may be sealed.

Next, a second embodiment will be described in detail.

In FIG. 5, 3 is a hood and 2 is a skirt. A seal ring 25 made of heat-resistant cast iron is provided at the bottom of the skirt 2.

The contact surface 23 of this seal ring 25 with the outer peripheral surface 27 of the furnace mouth
is serrated. 24 is a cooling water channel.

This seal ring 25 is attached to the bottom of a support ring 19 that supports the skirt 2, and is moved up and down together with the skirt 2 by a skirt cylinder 21 connected to a bracket 20 provided on the support ring 19. Note that 22 is a seal jacket and 23 is a seal cylinder.

Regarding the operation of this embodiment configured as described above, the seal ring 25 moves up and down together with the skirt 2.

At the time of sealing in the refining process, the seal ring 25 is crimped onto the outer periphery 27 of the furnace mouth by the skirt cylinder 21.

Due to this pressure bonding, the high temperature slag deposited on the outer periphery 2T of the furnace mouth is rapidly cooled by the contact surface 23 of the seal ring 25, and the thermal shock caused by this rapid cooling causes two cracks.

When this crack occurs, the pressing of the skirt cylinder 21 is further crushed by force.

After crushing the slag in this manner, the surface 23 of the seal ring 25 and the outer periphery of the furnace mouth 21 are brought into contact with each other.

The saw-toothed contact surface 23 facilitates slag crushing, and when pressed against the outer periphery 27 of the furnace mouth, it acts as a kind of labyrinth seal, which strengthens the seal.

In addition, even if the slag is not crushed by the temporary slag and the surface of the furnace mouth outer periphery 27 is not exposed, the convex portions of the slag forming an uneven surface are crushed,
According to the sealing device of the present invention, which is crimped and sealed by one of the sawtooth-shaped contact surfaces 23, as described in detail above, a sealing ring having a circular cross section made of heat-resistant cast iron is attached to the lower part of the skirt. Since the seal ring is cooled, pressing the skirt cylinder destroys the slag due to the combined effects of force, thermal shock, and point contact between the seal ring and the slag, and prevents contact between the seal ring and the slag. It was possible to achieve close contact and complete sealing. In addition, a seal ring made of heat-resistant cast iron is installed at the bottom of the skirt to provide mechanical strength and is water-cooled, and the sealing surface is serrated to prevent thermal shock and pressing force from accumulating on the outer periphery of the furnace mouth. Due to the mutual action, it was crushed and the seal ring and the outer periphery of the furnace mouth were able to be crimped and sealed.

In addition, since the surface is serrated, it is easy to crush the slag, and it also has a labyrinth seal effect.
We were able to create a perfect seal between the furnace mouth and the skirt.

Furthermore, since the seal ring is made of heat-resistant cast iron, it has sufficient durability and mechanical strength against high temperatures, and can provide a long-life sealing device.

In addition, this complete sealing and long service life not only allow high purity CO gas to be recovered, but also have excellent effects such as fewer repairs and improved operating efficiency.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing the entire converter exhaust gas treatment equipment;
- ゛Figure 2 is a conventional sealing device, which is a vertical cross-sectional view of a sealing device that seals directly with a skirt, and Figure 3 is a sealing device that seals with a separately provided seal ring. FIG. 3 is a partial vertical cross-sectional view showing only a portion of the sealing device in an enlarged manner. 2...Scar) 17...Seal ring 18...
Hollow part 21... Cylinder for suso j-) 23... Contact surface (serrated contact surface) 24... Cooling water channel 25.
...Seal ring 27...Outer circumferential surface of furnace mouth Applicant: Nippon Steel Corporation Applicant: Kawasaki Heavy Industries, Ltd. Figure 2 Figure 4

Claims (2)

[Claims] (1) A seal ring with a circular cross section made of heat-resistant cast iron is provided at the bottom of the skirt, the seal ring is made hollow, and cooling water is passed through the hollow part to cool the seal ring, thereby reducing thermal shock caused by this cooling. A sealing device between the furnace port and the skirt of a converter exhaust gas treatment equipment, characterized in that the sealing force of the skirt silling is used to destroy the seal, thereby sealing the space between the skirt and the furnace port. (2) A seal ring molded from heat-resistant cast iron is provided at the bottom of the skirt, and the contact surface between the seal ring and the outer circumferential surface of the furnace mouth is formed into a serrated shape, and water-cooled to prevent thermal shock and damage to the skirt cylinder. Destroys the slag with the pressure force of
A sealing device between the furnace mouth and the skirt of a converter exhaust gas treatment equipment, characterized in that the space between the skirt and the furnace mouth is sealed.