JPH07308740A - Pressure reduction apparatus for tundish for continuous casting and method of holding pressure thereof - Google Patents

Abstract

PURPOSE:To provide a pressure reduction apparatus of a tundish for continuous casting and a method for holding the pressure thereof, by which the operation can be executed while always holding the pressure reducing value in a pressure reducing circuit at the tundish side to a prescribed value or lower even at the executing step of the continuous casting, in which the tundish is laid in the high temp. atmosphere for a long time. CONSTITUTION:In the pressure reduction apparatus 10 and the method for holding the pressure in the tundish having the pressure reducing circuit 14 at the tundish side containing an actuator 18 and a evacuating unit 11 connected to the pressure reducing circuit through high pressure hoses 12, 13 so as to be freely touched/detached, the pressure reducing circuit 14 on the tundish side is provided with an relief valve 19 connected with at least one side of the reduced pressure side of the pressure reducing circuit 14 on the tundish side, and a drain pot connected to the exhaust side of the reduced pressure of the relief valve 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic device for a tundish for continuous casting, which is used for continuous casting of molten steel, and a pressure holding method for the same. The present invention relates to an apparatus and method for avoiding abnormal pressure rise in a hydraulic circuit due to a high temperature atmosphere around a dish.

[0002]

2. Description of the Related Art A tundish is a process in which molten steel is continuously cast into a slab, for example, in which molten steel from a ladle that has been subjected to molten steel refined in a converter is stored and impurities such as non-metallic inclusions are accumulated. It functions to float and to distribute molten steel for each strand. Therefore, the tundish is normally divided into 3 chambers by a refractory weir,
A molten steel flow hole is formed in the lower part of the weir. Thus, the molten steel from the ladle is supplied to the center chamber, where the non-metallic inclusions are floated, and the clean molten steel is supplied to the chambers on both sides from the molten steel flow holes at the bottom of the weir, and the stopper or By operating the sliding nozzle, molten steel is supplied to a continuous casting mold to perform continuous casting. The tundish is placed on a trolley, and during continuous casting it is preheated for several hours with the combustion flame of combustible gas such as coke oven gas,
Travel from the preheat position to the casting position on the mold.
The tundish is equipped with a hydraulic device, for example, a hydraulic device, so that handling such as preheating or elevating the tundish at the standby position can be performed.

[0003]

However, when performing continuous casting by moving the tundish from the preheat or standby position to the casting position, at least the actuator side of the hydraulic device is accompanied by the tundish, and the continuous casting is performed. A problem arises that the liquid pressure of the hydraulic device rises due to the high temperature atmosphere around the tundish in the stage. The hydraulic pressure in the hydraulic device used for handling such as raising and lowering the tundish is, for example, 14 MPa (142 k).
gf / cm ² ), but in the process of performing continuous casting, due to the high temperature atmosphere around the tundish, the pressure is 2-2.5 times (28-35 mPa (284
355) kgf / cm ² )), and there is a risk of destroying the components of the hydraulic circuit such as pipelines and valves, which is a problem from the viewpoint of work safety and equipment maintenance. No prior art is found as a means for solving such a problem. INDUSTRIAL APPLICABILITY The present invention is for continuous casting in which the tundish can be operated while maintaining the hydraulic pressure value of the hydraulic circuit on the tundish side at a predetermined value or less at all times even in the continuous casting execution stage where the tundish is placed in a high temperature atmosphere for a long time. An object of the present invention is to provide a tundish hydraulic device and a pressure holding method thereof.

[0004]

A method according to the above-mentioned object.
The hydraulic device for continuous casting tundish described is a liquid for a continuous casting tundish having a tundish side hydraulic circuit including an actuator and a hydraulic pressure generation unit detachably connected to the tundish side hydraulic circuit via a high pressure hose. A pressure device, wherein the tundish-side hydraulic circuit includes a relief valve connected to at least one hydraulic side of the tundish-side hydraulic circuit, and a drain pot connected to a hydraulic pressure relief side of the relief valve. And is configured. The pressure maintaining method for a hydraulic device for a continuous casting tundish according to claim 2 is a pressure maintaining method for a hydraulic device for a tundish for continuous casting of molten metal, wherein the tundish is in a standby state of the tundish. A liquid pressure generating unit for operating the tundish side hydraulic circuit provided at the standby position, and the tundish side liquid by releasably connecting the hydraulic pressure generating unit and the tundish side hydraulic circuit. When a continuous operation of the tundish is used by operating an actuator of a pressure circuit, a relief valve having a set pressure higher than the operating pressure provided in the tundish-side hydraulic circuit section is operated to operate one of the thermally expanded operating liquids. The part is configured to be discharged to the drain pot.

[0005]

In the hydraulic device for a continuous casting tundish according to claim 1 and the pressure holding method for the hydraulic device for a continuous casting tundish according to claim 2, when the tundish is in the standby position, , Forming a circuit in which the hydraulic pressure generation unit and the tundish-side hydraulic circuit are connected to operate the actuator of the tundish-side hydraulic circuit,
When the tundish is transported from the standby position, the tundish-side hydraulic circuit and the hydraulic pressure generating unit are separated. And, when using the tundish for continuous casting, operate the relief valve on at least one of the tundish hydraulic circuit to prevent the liquid expansion when the tundish hydraulic circuit is exposed to high temperature. The resulting pressure is
When the set pressure of the relief valve is exceeded, it is released by the relief valve and the working liquid is caused to flow into the drain pot, thereby absorbing the abnormal pressure of the tundish side hydraulic circuit.

[0006]

EXAMPLES Next, examples embodying the present invention will be described to provide an understanding of the present invention. 1 is an overall circuit diagram of a hydraulic device for a tundish for continuous casting according to an embodiment of the present invention, and FIG. 2 is a circuit diagram of the hydraulic circuit for the tundish side.

As shown in FIGS. 1 and 2, a hydraulic device 10 for a continuous casting tundish according to an embodiment of the present invention includes a hydraulic pressure generating unit 11 and a high pressure hose 12 connected to the hydraulic pressure generating unit 11. And a tundish-side hydraulic circuit 14 connected via 13. These will be described in detail below.

The hydraulic pressure generating unit 11 uses a water / glycol solution as a working liquid, a hydraulic tank (not shown), a hydraulic pump, a relief valve for determining the working pressure,
And a switching valve, and high pressure hoses 12, 1 on the outlet side
3 is provided.

The tundish hydraulic circuit 14 includes
Couplers 15 and 16 with a stop valve connected to the high-pressure hoses 12 and 13, eight hydraulic cylinders 18 connected to the couplers 15 and 16 via a stop valve 17, and the addition of the hydraulic cylinder 18 A relief valve 19 connected to the pressure side, and a drain pot 21 connected to the relief valve 19 via a stop valve 20.
And a bypass valve 22 of the hydraulic cylinder 18.

The drain pot 21 is opened to the atmosphere through an air filter 23 provided at the upper part, and a drain valve 24 is provided at the bottom so that the accumulated liquid can be extracted. There is. The hydraulic pressure of the hydraulic device of this continuous casting tundish is approximately 14
The pressure of the relief valve is about 20 MPa at about 20 MPa.
It is about Pa (204 kgf / cm ² ).

Therefore, when using the hydraulic device 10 for the continuous casting tundish, first, the hydraulic pressure generating unit 11 and the tundish-side hydraulic circuit 14 are connected by the high pressure hoses 12, 13 in a standby state. , The stop valve 17 is opened, and the bypass valve 22 and the stop valve 20 are closed, and the switching valve in the hydraulic pressure generation unit 11 is operated to feed the liquid from the coupler 16 side, and the coupler 1
Hydraulic cylinder 1 with liquid returned from side 5 and connected in parallel
Move 8 to position. And the stop valve 17
Close and disconnect the high pressure hose from the couplers 15 and 16.

In this state, with the stop valve 20 opened and the relief valve 19 operable, the tundish is moved to the continuous casting position to perform a predetermined work.
Here, when the liquid trapped in the tundish side hydraulic circuit 14 expands due to the high temperature gas around the tundish and the pressure rises and exceeds the critical pressure (20 MPa), the relief valve 19 is activated. When opened, the working liquid moves to the drain pot 21 side, the pressure rise is limited to the critical pressure or less, and it is possible to prevent a worker from being injured or damaging an actuator such as a pipeline, a valve or a cylinder. When the liquid collects in the drain pot, the stop valve 24 is opened and the liquid is discharged.

In the above embodiment, the stop valves 17 and 2 are used.
0, the bypass valve 22 and the discharge valve 24 are manual valves, but electromagnetic valves may be used in some cases.

[0014]

As is apparent from the above description, the hydraulic device for a continuous casting tundish according to claim 1 and the pressure maintaining method according to claim 2 are used for continuous casting of molten metal. It is possible to prevent the hydraulic circuit attached to the tundish from being damaged by the expansion of the liquid caused by the high temperature atmosphere or to cause a human injury, and to perform safe continuous casting.

[Brief description of drawings]

FIG. 1 is an overall circuit diagram of a hydraulic device for a tundish for continuous casting according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of the tundish-side hydraulic circuit.

[Explanation of symbols]

 10 Tundish hydraulic device for continuous casting 11 Liquid pressure generating unit 12 High pressure hose 13 High pressure hose 14 Tundish hydraulic circuit 15 Coupler 16 Coupler 17 Stop valve 18 Hydraulic cylinder 19 Relief valve 20 Stop valve 21 Drain pot 22 Bypass Valve 23 Air filter 24 Discharge valve

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kenzo Adachi 1-3-1 Makiyama, Tobata-ku, Kitakyushu, Fukuoka Prefecture In Hamada Heavy Industries Co., Ltd.

Claims (2)

[Claims] 1. A tundish hydraulic device for continuous casting, comprising: a tundish-side hydraulic circuit including an actuator; and a hydraulic pressure generating unit removably connected to the tundish-side hydraulic circuit, the tundish-side hydraulic circuit comprising: The dish side hydraulic circuit has a relief valve connected to at least one hydraulic side of the tundish side hydraulic circuit, and a drain pot connected to the hydraulic pressure relief side of the relief valve. A unique tundish hydraulic device for continuous casting. 2. A pressure holding method for a hydraulic device for a tundish for continuous casting of molten metal, wherein a hydraulic pressure for operating a tundish side hydraulic circuit provided in the tundish in a standby state of the tundish. The generation unit is placed in the standby position, the hydraulic pressure generation unit and the tundish side hydraulic circuit are detachably connected to operate the actuator of the tundish side hydraulic circuit, and continuous casting of the tundish is used. Occasionally, a relief valve having a set pressure higher than the working pressure provided in the tundish side hydraulic circuit section is operated to discharge a part of the thermally expanded working liquid to a drain pot for continuous casting. How to maintain pressure in a tundish hydraulic system.