JPH063268Y2 - Sealing device for piping - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a pipe seal device used for shutting down a downcomer pipe of a blast furnace.

[Problems to be solved by the prior art and this device]

As shown in FIG. 6, the blast furnace A includes a dust remover (dust catcher) B, a gas cleaning device (ring slit washer) C, etc., and blast furnace exhaust gas containing CO gas is passed through an ascending pipe D and a descending pipe E. After introducing the gas to the gas cleaning equipment to remove dust and clean it, it is put in a hot air stove and burned, and this hot air is blown into the blast furnace from the tuyere F. The CO gas generated from the heat coke of the balance is burned by the in-furnace igniter G to make it harmless to CO ₂ gas, and then is diffused to the atmosphere from the bleeder valve H,
In this state, repair work such as gas cleaning equipment is being performed.

However, in such a state, CO ₂ and C
O gas may come down through the downcomer E, and in such a case, it is necessary to stop the construction or use an air mask or the like, which is a dangerous work in any case. I don't get.

In small blast furnaces, there is a case in which a sluice valve called a goggle valve is installed at the entrance of the dust remover and this sluice valve is closed on a closed day, but it is difficult to maintain, especially in the recent large blast furnaces. Is more than 3m,
Almost not installed.

On the other hand, in repair work for gas pipes, water pipes, etc., a device for inflating an air bag to shut off the pipe has been proposed (Japanese Utility Model Publication No. 55-9925, Japanese Utility Model Publication No. 59-45394, Japanese Patent Laid-Open No. Sho 59-45394). 6
3-130991 publication).

However, in the downcomer pipe of the blast furnace, high temperature CO ₂ gas generated in the furnace (for example, at the top of the furnace due to abnormal combustion)
(150-300 ℃) may also come down to the downcomer pipe, and a normal air bag may be deteriorated or damaged by high temperature gas.

This invention was made in view of such circumstances,
The purpose of the present invention is to provide a pipe sealing device capable of preventing deterioration and damage of a bag due to high-temperature gas, and reliably shutting off the pipe while purging the inside of the downcomer pipe of the blast furnace with stable gas (air etc.). To do.

[Means for Solving the Problems]

As shown in FIG. 1, the present invention is a sealing device in which a bag 1 made of an airtight material is inserted into a pipe and gas is blown into the bag to shut off the pipe. A large number of gas jet valves 2 that open at a certain pressure or higher are installed.

The bag 1 may be a spherical ball bag 1A or a second ball bag 1A.
As shown in the figure, it is possible to use a partition plate 1C provided with a ring-shaped bag 1B on the outer periphery thereof. The ball bag 1A or the bag 1B preferably has an outer diameter larger than the inner diameter of the tube, and an elastic member such as rubber or elastic synthetic resin or another flexible member can be used.

As the gas ejection valve 2, for example, a ball valve as shown in FIG. 3 can be used.

In addition, when there is a high temperature gas or the like on both sides of the shutoff portion, it is natural to provide the gas injection valve 2 on both sides, and the gas replacement at the time of working in the pipe is also performed by the shutoff body (ball bag 1A). It can be done smoothly by ejecting air.

[Action]

A small diameter manhole 3 is provided in the pipe, the bag 1 is contracted, and the gas ejection valve 2 is positioned on the hot gas side. The manhole 3 is inserted into the pipe, and then the introduction pipe 4 is inserted. Then, a gas such as air is blown into the bag 1 to inflate it. Until the bag 1 is completely inflated, no gas is blown out from the gas ejection valve 2, and the bag is inflated early to shut off the piping.

After that, when the pressure becomes equal to or higher than a certain pressure, the gas gradually blows out from the gas ejection port 2 to cool the bag body and prevent the hot gas from reaching, thereby preventing the bag 1 from being deteriorated or damaged.

〔Example〕

As shown in FIG. 4, this is an example in which the downcomer pipe E having a diameter of 4600 mm just above the dust remover B of the large blast furnace A is sealed using a rubber air ball bag 1A having a diameter of 4800 mm. A manhole 3 having an inner diameter of 600 mm is provided on the side wall of the, and an opening 5 having an inner diameter of 200 mm is provided at a position facing the manhole 3.

At the time of loading, as shown in FIG. 5, the tow rod 6 is inserted through the opening 5 and the hook 7 for fixing the bag 1A is attached to the hook thereof.
And pull the bag 1A in the contracted state into the tube. Next, portable electric blower 8 (2.3 m ³ / min ×
450 mm Aq) is used to supply low pressure air having a pressure of 400 mm Aq into the bag through the introduction pipe 4. Under such conditions, the air can be filled in the bag in about 15 minutes. When fully inflated, the fixing cord 7 is fixed to the floor. When the bag is filled, the pressure is further increased and the gas ejection valve 2
The air is gradually discharged from. When the air is no longer released, the air is replenished and the pressure is increased.

As shown in FIG. 3, the gas injection valve 2 has a cylindrical valve body 9 having an external thread, a valve seat 10 provided at the center of the valve body, and a ball capable of closing the valve seat 10. 11, a spring 12 for urging the ball 11 toward the valve seat, a spring retainer 13 attached to the valve body 9 and a mounting bracket 14, and a hole is formed in the bag 1A. It is fixed to the bag 1A by sandwiching a part of it with the mounting bracket 14.

When the ball 11 urged by the spring 12 blocks the opening of the valve seat 10 to prevent the air from being blown out and the internal pressure exceeds a certain pressure, the ball 11 resists the urging force of the spring 12 and the ball 11 moves toward the valve seat 10. Away from the inside, the air inside is jet 1
Blow out from 3A. The spring retainer is a screw type and the valve body 9
The spring pressure, that is, the set pressure can be arbitrarily adjusted by changing the mounting position on the valve body 9.

When sealing was performed using such an air ball bag, in the conventional case, the CO gas concentration becomes 0 ppm with respect to the CO gas concentration of 100 to 500 ppm, and the dust catcher,
The internal work such as the ring slit washer or the furnace top pressure recovery turbine could be carried out safely. In addition, the bag can be reliably sealed without deterioration or damage of the bag due to high temperature gas.

Although the downcomer pipe of the blast furnace has been described above, it is needless to say that the present invention can be applied to not only the downcomer pipe but also a pipe seal that may be deteriorated or damaged by temperature.

[Effect of device]

As described above, in the pipe sealing device according to the present invention, a large number of gas injection valves that open at a certain pressure or more are installed on the side surface of the bag to gradually release air, so that the bag is deteriorated by high temperature gas. Also, damage can be prevented, the pipes can be reliably cut off, and safe repair work can be performed.

[Brief description of drawings]

FIGS. 1 (i) and (ii) are schematic cross-sectional views showing the implementation of the present invention in order, FIG. 2 is a schematic cross-sectional view showing a modification of the sealing device of FIG. 1, and FIG. FIG. 4 is a cross-sectional view showing an example of a valve, FIG. 4 is a schematic view showing an embodiment of the present invention, FIGS. 5 (i) to (iii) are schematic cross-sectional views showing the order of implementation thereof, and FIG. It is a schematic diagram showing a blast furnace at the time of repair. 1 ... Bag, 1A ... Ball bag 1B ... Ring-shaped bag, 1C ... Partition plate 2 ... Gas ejection valve, 3 ... Manhole, 4 ... Introduction pipe, 5 ... Opening, 6 ... Truck rod, 7 ... Fixing cord 8 ... Portable blower, 9 ... Valve body 10 ... Valve seat, 11 ... Ball 12 ... Spring 13 ... Spring retainer 14 ... Mounting bracket

Claims (1)

[Scope of utility model registration request] 1. A sealing device in which a bag made of an airtight material is inserted into a pipe, and gas is blown into the bag to shut off the pipe. A pipe sealing device with a large number of injection valves installed.