JPH06306424A - Method for controlling filling pressure and holding pressure of mud with mud gun - Google Patents

Abstract

PURPOSE:To smoothly fill a mud into a tap hole to plug the tap hole without breaking the tap hole by making holding pressure at the cylinder of a mud gun the strength or lower of the refractory for forming the tap hole and controlling the holding pressure according to the ascent of the filling pressure of the mud, at the of filling the mud into the tap hole in a blast furnace. CONSTITUTION:At the time of plugging by filling the mud 12 into the tap hole 11 with the mud gun 10 after tapping molten iron from the blast furnace, the contacting pressure (holding pressure) at the cylinder tip of the mud gun 10 is preset to the strength or lower of the refractory for forming the tap hole 11 and also, held to the pressure near the compressive strength of the mud 12. Successively, after holding the mud gun 10 incliningly toward the tap hole 11, the mud 12 is pressed and filled into the tap hole 11 by working the cylinder 13 of the mud gun 10. In this case, as the filling pressure of the mud is risen, the filling pressure of the mud and the holding pressure are controlled to be raised so as to keep the holding pressure higher than the filling pressure of the mud. Without leakage of the mud from the tap hole 11 and damage to the refractory for tap hole 11, the mud 12 is smoothly filled into the tap hole 11 and the tap hole is plugged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of filling a filler (mud) used for closing the taphole of a blast furnace with the filler.

[0002]

2. Description of the Related Art For example, as shown in FIG. 4, a mud gun 10 has a mud barrel tip made of a refractory so that a mud barrel tip is adhered to a mud barrel to close the taphole of a blast furnace with a filler. The filling material 12 for closing the taphole that has been filled is extruded by the cylinder 13 and the filling material 12 is filled into the taphole and closed.

In this case, the filling reaction force generated when the filling material is filled into the taphole is held by pressing the mud gun barrel tip against the taphole surface at a set pressure which is 1.1 times or more the filling reaction force. Prevents leakage to the outside of the taphole and fills the filler material smoothly into the taphole. By the way, the mud filling pressure of the mud gun at the time of filling such a conventional filling material is 120-
It was 180 kg / cm ² .

[0004]

However, in the above-described method, when the mud filling pressure becomes high, the mud gun barrel tip adhesion pressure (hereinafter referred to as the holding pressure) for holding the mud filling reaction force becomes the filling pressure. In some cases, the pressure increased proportionally and the pressure became 2-3 times that of the conventional mud gun. When the holding pressure increases, the taphole surface made of refractory will
When a holding pressure exceeding the strength of the refractory material is received, it eventually breaks down, which may make it impossible to fill the filler in the taphole.

An object of the present invention is to hold the mud gun cylinder tip holding pressure within a range not exceeding the refractory strength, control the holding pressure as the mud filling pressure rises, and smoothly fill the filler into the taphole.

[0006]

DISCLOSURE OF THE INVENTION The present invention relates to a mud filling method for closing the taphole of a blast furnace with a filling material, in which the mud gun holding pressure is controlled to a predetermined mud filling pressure or more, and then the filling is performed. It is characterized in that the mud is filled while the holding hydraulic pressure is increased until the extrusion pressure reaches a preset maximum extrusion pressure.

[0007]

Function: The holding pressure of the mud gun when closing the taphole of the blast furnace is set in advance to a level not higher than the strength of the taphole refractory. Thus when the compression strength 200 kg / cm ² mud, is set to a highest possible filling pressure for example 180 kg / cm ² or more 200 kg / cm of less than ² in order to densely fill the mud. After that, the mud gun is tilted and held on the taphole surface to protect the refractory, and then the filling material is pushed into the taphole by the filling cylinder. As the mud filling pressure rises as it is extruded, the holding pressure is approximately 10% lower than the mud filling pressure.
Both the mud filling pressure and the holding pressure are controlled so as to increase so as to maintain a high level. According to the experiments by the present inventors, the final mud filling pressure is 300 for the densification of the mud.
It is good if it is at least kg / cm ^2, preferably 330 to 380.
If it is kg / cm ^2, a dense layer of sufficient mud can be obtained. According to the present invention, it is possible to prevent the mud from leaking from the taphole surface and the damage to the taphole refractory, and yet to smoothly close the taphole.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The features of the present invention will be specifically described below with reference to the drawings with reference to the embodiments. FIG. 2 shows a hydraulic control circuit for filling (a system) and holding (b system) the mud gun 10 used in the present invention. FIG. 2 (a system) shows a hydraulic circuit for mud filling operation of the mud gun, and (b system) shows a hydraulic circuit for holding operation of the mud gun. In the case of filling the taphole with the filling material (b system). The operation after the operation (system a) is performed, and the filling material is filled into the taphole 11. In FIG. 2, P
Is a hydraulic line supplied from a pump (not shown), T is a hydraulic line returning to a tank (not shown), and DR is a drain (not shown) line. Solenoid valves 1 and 3 are holding devices 9
The solenoid valve 2 is used for raising, the solenoid valve 4 is used for holding pressure, the solenoid valve 5 is used for moving the mud gun 10 forward, and the solenoid valve 6 is used for moving backward. The pressure switch 7 is used to detect the initial set pressure, and the pressure switch 8 is used to detect the maximum pressure set pressure.

In the case of closing the taphole with a mud gun, the control of the (b system) circuit will be described first. Solenoid valve 1
By operating 3 and 3, the tip of the mud gun is tilted to the tap hole surface and the tip of the mud gun is bonded to the tap hole surface, and the pressure preset by the pressure switch 7 (for example, holding pressure 198 kg / c
hydraulic pressure is set to 200 kg / cm ² when m ² ),
It is crimped and held by the solenoid valve 4. Next, the control of the (a system) circuit will be described. By operating the solenoid valve 5, the filling material starts filling into the taphole. Then, the filling progresses while increasing the filling extrusion pressure, and the preset maximum filling pressure (for example, 300 to 350 kg / cm ² is arbitrarily set) is detected by the pressure switch 8.

FIG. 3 shows the operation sequence of the holding device 9 and the mud gun 10. It is operation | movement explanatory drawing of solenoid valve 1-6 and pressure switch 7,8. In this way, the holding pressure on the tap hole surface of the mud gun barrel tip is held so that it is softly pressed against the exit mouth refractory, and at the same time as the start of filling, 1.1 times the filling pressure is secured while filling It becomes possible to sufficiently fill the refractory material at the tapping surface of the taphole.

FIG. 1 shows an example of a method for controlling a mud filling pressure and a holding pressure of a mud gun according to the method of the present invention. In the figure, for example, when the filling start pressure is 180 kg / cm ² , the holding pressure is about 1.1 times the filling pressure. As the filling pressure increases, the holding pressure increases while maintaining 1.1 times the filling pressure, and the mud filling is completed when the pressure reaches a preset pressure, for example, 350 kg / cm ² .

[0012]

As described above, according to the present invention, since it can be controlled by the pressure switch for initial setting and the pressure switch at the maximum holding pressure, damage to the refractory on the taphole surface can be prevented. . Further, according to the present invention, a high strength and high corrosion resistance taphole filler can be used.

[Brief description of drawings]

FIG. 1 is a diagram showing the relationship between filling time, holding pressure, and filling pressure.

FIG. 2 is a diagram showing a mud gun hydraulic control circuit according to an embodiment of the present invention.

FIG. 3 is a diagram showing an operation sequence of the mud gun of the present invention.

[Fig. 4] Conceptual diagram of filling of taphole and mud gun

[Explanation of symbols]

 1, 2, 3, 4, 5, 6 Solenoid valve 7, 8 Pressure switch 9 Holding device 10 Mud gun 11 Tap hole 12 Filling material 13 Cylinder

Claims (1)

[Claims] 1. A mud filling method in which a blast furnace tap hole is closed with a filling material, the mud gun holding pressure is controlled to be equal to or higher than a preset mud filling pressure, and then the filling extrusion pressure is set to a preset maximum value. A method of controlling a filling pressure and a holding pressure of a mud gun, which comprises filling a mud while pressurizing a holding hydraulic pressure until reaching an extrusion pressure.