JPS5839026B2 - suction head - Google Patents

Description

[Detailed Description of the Invention] The present invention uses a suction head to vacuum scum or slag (hereinafter referred to as scum) on the surface of the molten metal, and during the suction, water is jetted against the scum to cool it and break it into small pieces. The present invention relates to a suction head of a scum removal device, in which the finely divided scum and water are separated and removed from suction air containing a mixture of water vapor and scum, which is conveyed to a separation hopper.

In such a suction head, a cooling jacket is provided on the outside of the inner cylinder that forms the scum suction path, and the water supplied into the cooling jacket is used to cool iron water against the scum sucked up through the suction port pipe. It is being considered that the scum can be injected to promote cooling and fragmentation of the scum.

By the way, if the suction pressure changes abnormally due to a power outage or failure of equipment such as the vacuum pump, separation hopper, scum suction path, etc., conventionally a person would check this and manually operate the cock installed in the middle of the piping system. The water supply had been stopped.

However, even if the cock is shut off, a considerable amount of water within the suction head or between the cock and the suction head flows onto the molten metal, which is very dangerous.

The present invention solves the above-mentioned conventional drawbacks, and aims to provide a suction head that can completely cut off the injection of water into the scum suction path when the suction pressure changes abnormally.

In order to achieve the above object, the suction head of the present invention includes:
The structure includes an injection port that injects water into the scum suction path, and an opening/closing member that opens and closes the injection port.

According to this configuration, since the injection port that injects water into the scum suction path can be opened and closed by the opening/closing member, if the suction pressure changes abnormally, the injection of water into the scum suction path can be completely shut off. This makes it possible to reliably prevent water from flowing onto the molten metal.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In the figure, 1 is a suction head, 2 is a scum suction path, and the suction head main body consists of an inner cylinder 3 that forms this scum suction path 2, an outer cylinder 4 that forms a cooling jacket on the outside thereof, and this suction head. A suction head 1 is constituted by a suction port pipe 6 attached to the lower end of the main body.

A socket (not shown) at the upper end of the suction head body
A vent pipe (not shown) is connected through the suction port pipe 5.
The scum sucked from the scum is sufficiently accelerated through a scum suction path 2 that extends long upward, and is then conveyed to a separation hopper (not shown) via the vent pipe.

Note that the scum suction path 2 is also formed by the suction port pipe 5.

The upper and lower ends of the outer cylinder 4 are fitted between an annular upper plate 6 and a lower plate 7 and connected to the inner cylinder 3 to form a cooling jacket. Although not shown, this cooling jacket has a safety valve and an air vent valve mounting pipe. A seat and a water supply pipe seat are attached.

On the other hand, an outer skirt 9 having a male threaded portion 8 on the outer peripheral surface hangs down from the lower plate 7, and the suction port pipe 5 is screwed and attached to the outer skirt 9, and inside the outer skirt 9, the lower plate 7 has a plurality of communication holes 10 at appropriate intervals in the circumferential direction.
is drilled.

Reference numeral 11 denotes an annular injection port formed between the lower end of the suction head main body and the suction port pipe 5, and the water supplied into the cooling jacket is ejected downward from the communication hole 10 to form the injection port 11. It is configured to eject from the air toward the center of the suction port pipe 5.

An inner skirt 12 is suspended from the center position of the lower surface of the lower plate 7 to form an annular space 13 between the lower end 3a of the inner cylinder 3 and the inner skirt 12, and between the inner skirt 12 and the outer skirt 9. An annular space 14 is formed, and the communication hole 10
is bored in the lower plate 7 on the outside of the inner skirt 12 and opens into the annular space 14.

In the front = 15, the lower end 3a of the inner cylinder 3, and the inner skirt 12 are completely sealed, and a sealed space 17 is formed between the opening/closing member 15 and the lower plate 7.

Further, inside the inner skirt 12, an air supply pipe 18 is passed through the lower plate 7 from above and opened into the sealed space 24, and the air supply pipe 18 passes through the cooling jacket, penetrates the upper plate 6, and is exposed to the outside. It is connected to an air source via an air solenoid valve (not shown).

Further, the lower end surface of the opening/closing member 15 is formed into a tapered surface 15a facing outward so that it is normally pushed upward by the water pressure passing through the injection port 11, and on the other hand, when water is shut off, the shutoff is ensured. To do this, the suction port pipe 5 is provided with a groove 19 into which the lower end of the opening/closing member 15 is fitted when it is lowered, and a gasket 20 is fitted therein.

Furthermore, in order to prevent water leakage from the threaded joint between the suction port pipe 5 and the suction head main body, a gasket groove 21 is recessed in the portion of the suction port tube 5 where the lower end surface of the outer skirt 9 contacts, and a gasket 22 is fitted therein. It is.

Next, to explain the operation, when water is supplied to the cooling jacket with the suction head facing above the molten metal, and the vacuum pump (not shown) is activated to suck air, scum is sucked in from the suction port pipe 5. At the same time, water is injected from the injection port 11, and the scum is rapidly cooled by the action of the water, and the scum is broken into small pieces and sent to the separation hopper.

Here, if the suction pressure changes abnormally, such as when the vacuum pressure becomes atmospheric pressure due to a power outage or a failure of the separation hopper, etc., the pressure sensor detects this pressure change and closes the water supply solenoid valve to the cooling jacket. At the same time, the air solenoid valve to the air supply pipe 18 is opened.

Therefore, air is sent into the closed space 17 and the opening/closing member 1
5 is pushed down against the water pressure of the injection port 11, and its lower end comes into pressure contact with the gasket 20 in the groove 19, so that the injection port 11 is completely closed.

When the pressure becomes normal, the pressure sensor is activated again and air supply to the air supply pipe 18 is stopped, while water supply to the cooling jacket is started and water is injected from the injection port 11.
Scum suction is resumed.

Note that, since the sealed space 1T is completely sealed by the O-ring 16, there is no air leakage when the opening/closing member 15 moves up and down, and water can be shut off reliably.

Furthermore, before the start of water supply, the opening/closing member 15 is fitted into the groove 19 of the suction port pipe 5 due to its own weight, but it remains pushed upward by the water supply, and the water flows toward the center of the suction head along the path shown by the arrow. It is squirted.

The opening/closing member 15 is designed to operate even when the suction port pipe 5 or the scum conveying path is clogged with molten metal or scum and the vacuum pressure is abnormally increased.

In addition, the present invention is applicable to the removal of scum in Nil electric furnaces, scum in steelmaking ladles, scum in low frequency furnaces and reverberatory furnaces, scum in cupola ladles, scum in rimmed steel ingots, etc.
It can also be applied to remove scum during metal melting.

In the present invention, the gasket 28 may be omitted depending on the case, but it is preferable to have the gasket 28 because water can be shut off more reliably.

As described above, according to the present invention, since the opening/closing member for opening and closing the injection port is provided, when the internal pressure of the suction head changes abnormally, the opening/closing member can shut off the water injection to the scum suction path, unlike the conventional method. It is possible to eliminate the danger of water falling into the molten metal without being able to drain it immediately as when operating the water supply cock, and it is also possible to completely drain the water, which has a great effect on safety.

[Brief explanation of the drawing]

The drawing is an enlarged vertical cross-sectional view of a main part of a suction head in an embodiment of the present invention. 2... Scum suction path, 11... Injection port, 15... Opening/closing member.

Claims (1)

[Claims] 1. A suction head characterized by having an injection port that injects water into a scum suction path, and an opening/closing member that opens and closes the injection port.