JP2764848B2 - Tuyere care equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tuyere inner surface care apparatus for replacing a dipping nozzle (hereinafter abbreviated as IN) of a steelmaking tundish.

[0002]

2. Description of the Related Art In general, molten steel carried by a pot from a converter in a continuous casting facility is once stored in a tundish and then injected into a mold through a submerged nozzle attached to the bottom tuyere. The service life of the tundish is 100 charges or more, while the service life of the immersion nozzle is as short as 5 to 10 charges. Therefore, the replacement of the immersion nozzle is indispensable in the continuous casting operation.

When the types of immersion nozzles are broadly classified, there are an integrated type in which the flow rate of molten steel is adjusted by raising and lowering a stopper, and a divided type in which the flow rate is adjusted by a horizontal sliding nozzle.

[0004] The former integrated type immersion nozzle is usually an interior type that is mounted from the inside of the tundish. When replacing the tundish, after the temperature of the tundish brick drops, the brick corresponding to the tuyere portion is broken and removed. It is common to insert and install a new immersion nozzle by replacing with a new one. However, since tuyere bricks are constructed after the temperature drops, continuous use of tundishes becomes impossible, and there is a disadvantage that material costs and labor costs for replacing bricks increase.

On the other hand, in the latter split type immersion nozzle, although the immersion nozzle can be easily replaced, a drift is likely to occur in the immersion nozzle portion when the molten steel is injected into the mold, and the molten steel flow state in the mold is compared with that of the integrated type. It has the disadvantage of being easily changed. For this reason, in the hot rotation of the tundish, it is desirable to use an integrated immersion nozzle that is advantageous in terms of quality as an exterior type that is mounted from the outside of the tundish.

Conventionally, when exchanging this type of exterior-integrated immersion nozzle, when cleaning the tuyere surface while hot, a tool such as a breaker or a bur is used by hand from the tuyere opening on the lower surface of the tundish. Therefore, foreign matter such as mortar remaining on the tuyere surface is removed, but it is a so-called 3K work that is dangerous under high temperature and extremely bad environment by manual work,
Work efficiency is low and it takes a long time.

[0007] On the other hand, conventionally, it has been attempted to easily replace the immersion nozzle while hot, and a pulling device that pulls out the old immersion nozzle from the outside of the tundish and a cleaning device that cleans the mounting hole after the immersion nozzle is pulled out. There has been proposed an exchange device in which a mounting device for mounting a new immersion nozzle from the outside of a tundish is mounted on a bogie (Japanese Utility Model Application Laid-Open No. 56-1).
22553).

[0008] Of these, the cleaning device is particularly one in which a cleaning tool rotated by a motor is attached to the tip of a shaft that is raised and lowered by a lifting cylinder, and the cleaning tool is rotated to clean and shape the inside of the nozzle mounting hole. There is a statement that it is sufficient to use a cleaning tool such as a wire brush or a cutter. Therefore, when a grinding bite or a grinding wheel is applied to cut or polish and remove foreign matter adhering to the tuyere surface, it is presumed that these will be fixed and attached to the turning base.

[0009]

However, as in the case of the above-described cleaning device, only a structure in which a cleaning tool is attached to the tip of a rotating shaft that is lifted and lowered by a lifting and lowering cylinder, the thermal deformation of the tundish, the stopping accuracy of the shaft, and the mechanical accuracy. Due to the backlash and the like, it is difficult to set the cleaning tool precisely at the center of the nozzle insertion hole, and damage to the tuyere cannot be avoided.

In a configuration in which the grinding tool or the polishing grindstone is simply fixed to the turning base, the cutting load becomes large unless the feed speed of the cutting tool is delicately controlled, so that the turning of the cutting tool is stopped or the tuyere brick is cut. Troubles such as damage occur. In grinding and polishing, since the grinding speed is low, it takes a long time to clean. SUMMARY OF THE INVENTION An object of the present invention is to provide a tuyere care device which can solve the above-mentioned drawbacks and can efficiently care for the inner surface of the tuyere without stopping the cutting tool or damaging the tuyere.

[0011]

In order to achieve the above object, a tuyere care device according to the present invention comprises a plurality of swivel bases, each having a single stage, extending around a rotary shaft in multiple stages in the vertical direction of the rotary shaft. The base of the tool holder is pivotally supported on each of the tops of the revolving bases so as to be swingable. The blade is swingably pivoted by a shaft, and the cutting tool can be expanded and contracted by the turning centrifugal force. A saw blade and a flat blade which are out of phase as the cutting tool are provided on the top of the turning base which constitutes the above-mentioned one stage and is located in the circumferential direction. Are provided in combination in the circumferential direction (claim 1).

Further, the tuyere care device according to the first aspect is characterized in that:
A dresser for finishing is provided as a cutting tool on the top of the revolving base which is located in the circumferential direction and constitutes the lowermost step (claim 2). The material of these cutting tools is made of a material slightly less strong than the tuyere strength. (Claim 3) is preferable.

[0013] In the tuyere maintenance device of the present invention, a turning drive means for turning the rotary shaft to turn the cutting tool, a control device for controlling a turning speed by the turning drive means and controlling a maintenance ability by a turning centrifugal force. It is good to use while controlling the care ability by turning speed adjustment. At this time, if the control device has a function of intermittently operating the turning drive means and inching the turning of the cutting tool (claim 4), the care ability can be amplified by the inching turning.

Further, in the tuyere care device according to claim 4,
The control device includes a turning load measuring means, and has a function of entering a low-speed turning motion for avoiding damage to the tuyere surface when the turning load monitored by the turning measuring means falls below a predetermined value. In this case, damage to the tuyere surface can be avoided.

[0015]

When inserted into the tuyere and the rotating shaft is rotated, the whole blade arranged in a frustoconical shape always expands and contracts according to the shape of the inner surface of the tuyere due to the rotating centrifugal force. That is, each blade tool is rotationally displaced about the base pivot point of the blade holder and the pivot axis of the blade tool, and is constantly pressed against the inner surface of the tuyere as shown in FIG. Adhered foreign substances (such as mortar) are pulverized.

Therefore, under the configuration in which the cutting tool is expanded and contracted by the turning centrifugal force, fine adjustment of the cutting of the cutting tool becomes unnecessary, and unstable phenomena such as stop of turning during maintenance can be avoided. Also, since the centrifugal force is used, the turning power can be set small,
Strength and the like can be simplified.

Under a configuration in which a saw blade having a phase difference and a flat blade are combined as a cutting tool (Claim 1), the blade is first pulverized into a groove shape by a saw blade tool having a phase difference, and then the remaining portion other than the groove is formed. Since the powder is pulverized by the flat blade, the maintenance ability is amplified, the foreign matter adhering to the tuyere surface can be removed in a short time with a light load, and the tuyere surface can be efficiently cleaned. Mao,
A dresser for finishing is not essential for such a function, and is provided as needed.

The construction in which a material having a slightly lower strength than the tuyere strength is used as the material of the cutting tool (claim 3) is effective in preventing damage to the tuyere surface due to excessive care.

Also, a swing driving means and a control device therefor are provided to adjust the swing speed so as to control the maintenance ability by the swing centrifugal force. Scale according to the shape. Then, a configuration in which the control device jogs the turning of the cutting tool (Claim 4)
Below, the blade is strongly pressed against the tuyere surface due to the inertia at the time of turning stop, and the care ability is greatly amplified.
In particular, in the combination of the first aspect in which a saw blade and a flat blade are used as the cutting tools, the maintenance ability is dramatically improved, and the maintenance can be performed with a light load and in a short time.

Further, in a configuration in which the tuyere enters a low-speed turning motion for avoiding damage to the tuyere when the turning load falls below a predetermined value, the finishing is performed while avoiding damage due to excessive maintenance of the tuyere. It can shift to a care process.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to one embodiment shown in the drawings. 1 to 3, an IN (immersion nozzle) exchange truck 3 for a tuyere 2 of a tundish 1 is provided so as to be able to travel on a truck traveling rail 5 by wheels 4, and the IN exchange truck 3 has an IN recovery device A , Tuyere care device B, IN
The insertion device C is mounted in this order.
A portion of the IN / mortar switching trolley 3b connected to the frame 3a of the N exchange trolley 3 has an IN adjacent to the IN insertion device C.
Preheating furnace D, mortar table E, IN-mortar transfer device F
Is installed. The IN replacement work is performed according to a procedure of IN collection → maintenance of tuyere → IN transfer → mortar transfer → IN insertion.

At this time, the carriage 3 moves on the rail 5 (1) first, the collection device A advances to the collection position facing the tuyere 2,
(2) After the collecting operation, the care device B advances to the cleaning position facing the tuyere 2, and (3) after the cleaning operation of the tuyere inner surface, the IN insertion device is prepared by the IN-mortar transfer device F by the time. In order to insert the IN set in C into tuyere 2,
The insertion device C moves forward to the collection position facing the tuyere 2,
(4) After the IN insertion (supply) work, the rail 5 is retracted to the standby position. In these operations, the recovery device A, the care device B, and the IN insertion device C advance from the standby position indicated by the solid line in FIG. 1 to the operation position indicated by the dotted line.

The present invention is particularly directed to the maintenance device B for the inner surface of the tuyere. FIG. 4 shows the appearance of the main body 6 of the tuyere maintenance device, and FIG. In the illustrated example, the tuyere care device main body 6 is provided with a combustion,
It has a metal push-up head 7 made of a sublimable material (for example, wooden), but is not essential.

In FIGS. 4 and 5, the rotary cylinder 13 fitted over the rotary shaft 11 and fixed to the rotary shaft 11 with screws 12 is moved from the same height position around the rotary cylinder 13 as shown in FIG. Three turning bases 14 are extended so as to form a substantially triangular shape. And this turning base 1
At the top of the triangle of FIG.
Is pivotally mounted by a shaft 15 and the holder 16
A cutting tool 17 is pivotally mounted on a shaft 18 so as to be freely swingable. That is, when the rotating shafts 11 and 13 rotate, the rotating centrifugal force causes the rotation of the holder 16 around the shaft 15 and the rotation of the cutting tool 17 around the shaft 18, and the length up to the tip of the tip expands / contracts. Link mechanism.

The three turning bases 14 are provided in a plurality of stages in the vertical direction of the rotating shaft, and the tops of the adjacent upper and lower turning bases 14 are, as shown in FIG. The positions of the upper and lower steps are shifted in the circumferential direction so as to protrude from the center between the open legs. Therefore, when viewed from above, the blades 17 are arranged in six rows in the circumferential direction.

Cutting tools 1 attached to each cutting tool holder 16
7, three types of cutting tools 17a, 17b, 17c shown in FIG.
And a dresser 17d shown in the lower part of FIG. FIG.
The cutting tool 17a shown in FIG. 8A is composed of a saw blade having two straight blades a protruding radially outward in a mountain-shaped cross section at positions spaced apart in the axial direction. The cutting tool 17b shown in FIG. 17a comprises a saw blade having two straight blades b out of phase with each other.

The cutting tool 17c shown in FIG. 8C is composed of a flat blade c having an axial width and covering the area of the saw blades 17a and 17b. The dresser 17d is formed by forming a thin metal wire into a cylindrical brush shape. These cutting tools 17
For the material of, a material having a slightly lower strength than the tuyere surface is selected in order to prevent damage due to excessive maintenance of the tuyere surface.

These cutting tools 17 are provided in the order of the cutting tools 17a, 17b, 17c in the circumferential direction on the top of the revolving base 14 which forms the above-mentioned one stage and is located in the circumferential direction. In this embodiment, the same type of cutting tool is positioned in each of the six rows, and dressers 17d are provided for the lowermost row and the turning base in the preceding row. However, these are not essential. That is, each of the blades 17 can be configured by combining a plurality of saw blades, phase-shift saw blades, and flat blades for each stage including two stages from the lower side.

The shaft 15 pivotally supporting the base 16a of the blade holder 16 is parallel to the rotary shaft 11, while the shaft 18 pivotally supporting the blade 17 to the holder 16 is flared with respect to the rotary shaft 11. The angle of inclination is set so as to substantially coincide with the inner surface of the tuyere to be maintained, that is, the angle of inclination of the top of the immersion nozzle. That is, the blades 17 are arranged so that the envelope of the whole blades forms a frustoconical shape following the inner surface of the tuyere, and the shaft 18 restricts each blade 17 from falling in the turning direction with respect to the inner surface of the tuyere 2. ing.

Since the main body 6 is inserted into the tuyere 2 by the elevating mechanism and the rotary shaft 11 is rotated by the turning drive mechanism, the main body 6 is arranged in a conical shape as described above. The entire cutting tool 17 expands and contracts in accordance with the shape of the inner surface of the tuyere due to the turning centrifugal force. That is, each cutting tool 17 rotates while pressing against the inner surface of the tuyere 2 as shown in FIG. Due to this swiveling pressure, foreign matter (such as mortar) adhered to the tuyere surface is first crushed into grooves by two kinds of saw blade-shaped cutting tools 17a and 17b having different phases, and the remaining portion other than the grooves is flat blade-shaped. It is pulverized by the cutting tool 17c and finally finished by a dresser 17d. Therefore, the tuyere surface is efficiently cleaned.

The above-mentioned turning drive mechanism and elevating mechanism can have any structures, but in this embodiment, they have the structure shown in FIG. In FIG. 9, the right side from the center axis indicates the case where the care device main body 6 is at the lowered position, and the left side indicates the case where the care device main body 6 is at the raised position. The lower portion of the rotary shaft 11 is disposed in a bottomed cylindrical movable frame 19, and is supported by a seat frame member 20, a double row conical roller bearing 21 and a cylindrical roller bearing 22 at the opening edge of the movable frame 19. Have been. In the movable frame 19, a hydraulic motor 23 as a turning drive means is coaxially attached to the lower end of the rotating shaft 11, and the rotating shaft 11 is rotated by the hydraulic motor 23.

The movable frame 19 is disposed in a cylindrical fixed frame 26, and the bottom lower surface of the movable frame 19 is fixed to the fixed frame 26.
And is supported by a hydraulic cylinder 25 for raising and lowering provided between the bottom and the bottom surface of the hydraulic cylinder. Reference numeral 27 denotes a guide mechanism 27 provided between the movable frame 19 and the fixed frame 26 to guide the movable frame 19 in the vertical direction during the elevating operation.

As described above, the entire cutting tool 17 arranged in a frusto-conical shape always expands and contracts according to the shape of the inner surface of the tuyere as shown in FIG. Therefore, by controlling the turning speed, the maintenance ability by the centrifugal force can be controlled.

At this time, (1) the maintenance ability can be amplified by swaying the turning instead of turning at a uniform rotation speed. (2) Further, by adjusting the turning speed, it is possible to prevent the stop of the cutting tool and the damage to the tuyere, and it is possible to realize safe and stable hot maintenance. In addition, as the turning drive means, a known power source capable of performing a rotary motion such as an electric motor, a hydraulic motor, and an air motor can be used.

FIG. 10 shows an example of control in the tuyere maintenance work. Here, it is assumed that the control device that controls the turning speed of the turning drive unit has a turning speed motion load measuring unit and has a function of monitoring the turning load by the measuring unit. In addition, as a measuring means, an ammeter is provided in the case of turning drive by an electric motor, and a pressure gauge is provided in the case of turning drive by a hydraulic motor, an air motor, or the like.

(1) First, the care device main body 6 is raised by the lifting hydraulic cylinder 25, and the care device main body 6 is inserted into the tuyere 2.

(2) Next, a high-speed jogging turning motion by the turning driving means is started. In this high-speed jogging movement, the blade 17 contracts due to the inertia at the time of starting rotation, collides with the tuyere surface due to the centrifugal force generated by the rotation, and the blade 17 is pressed against the tuyere surface due to the inertia at the time of stopping rotation. Therefore, the foreign matter adhering to the tuyere surface such as mortar can be crushed by the force obtained by amplifying the centrifugal force due to the continuous turning motion at a uniform speed. This high-speed jogging and revolving step can be omitted when the deposit is small.

(3) Following the high-speed inching turning motion, the high-speed continuous turning motion is started. In the continuous swirling motion, the crushed foreign matter is finely pulverized and dropped by the pressing force of the blade tool 17 against the tuyere surface by the swirling centrifugal force. This pulverization is performed by a groove-shaped pulverizing step using saw blade-shaped blades 17a and 17b having different phases, and a flat blade-shaped blade 1
The process is efficiently performed by repeating the step of pulverizing in step 7c.

(4) When the turning load monitored by the exercise load measuring means falls below a predetermined value, the vehicle shifts from the high-speed continuous turning motion to the low-speed continuous turning motion. This means that the turning speed is reduced to avoid damage to the tuyere surface, and the process proceeds to the finishing care process. At this stage, dresser 17
d is located on the outside of the tuyere and the surface finish is executed.

(5) When the load further decreases, the maintenance work is terminated. That is, the maintenance device main body 6 is lowered by the hydraulic cylinder 25, and the turning by the hydraulic motor 23 is stopped. With the above control, the tuyere surface can be maintained with a light load and in a short time.

4 and 5, a metal lifting head 7 attached to the top of the tuyere maintenance device main body 6 is shown.
Is for pushing up and peeling and removing the metal layer 27 remaining on the upper surface of the tuyere 2 after the IN has been detached, without using a manual operation or an offline exclusive metal lifting device.
In this example, it is wooden.

The metal lifting head 7 is formed in a columnar shape.
The attachment is performed by inserting the attachment leg 7a provided at the center of the lower surface into the center hole at the top of the tuyere maintenance device main body 6, that is, the hole 13a provided at the head of the rotary cylinder 13. Then, the set metal push-up head 7 is used in the tuyere maintenance work immediately after the IN is removed and collected by the IN collection device A.
It is inserted into the tuyere 2 at the same time as the tuyere care device body 6.
The metal push-up head 7 is a consumable that is burned and sublimated in the tundish.

The driving nails 7b provided at appropriate places in the circumferential direction on the outer peripheral surface of the head 7 cause cracks or grooves in the adhered foreign matter 28 such as mortar remaining on the inner surface of the tuyere upper end when the head 7 is raised. Of the tuyere maintenance device 6
It works to facilitate removal by.

[0044]

As described above, according to the present invention, the following excellent effects can be obtained. (1) By expanding and contracting the cutting tool by rotating centrifugal force,
Fine adjustment of the cutting depth of the cutting tool is not required, and unstable phenomena such as turning stop during maintenance can be avoided. Further, since the centrifugal force is used, the turning power can be set small, and the structure, strength, and the like can be simplified. (2) The jogging of the turning and the combination of the saw blade and the flat blade having different phases can dramatically improve the maintenance ability, and the light load can be performed in a short time. (3) The maintenance ability can be controlled by adjusting the turning speed, and by monitoring the turning load, damage due to excessive care of the tuyere surface can be avoided. In addition, damage to the tuyere can be reduced by selecting the material.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an IN exchange bogie equipped with a tuyere care device according to one embodiment of the present invention.

FIG. 2 is a plan view of the IN exchange bogie of FIG. 1;

FIG. 3 is a side view showing the IN exchange bogie of FIG. 1 in a partial cross section.

FIG. 4 is an external view showing a tuyere care device according to an embodiment of the present invention.

5 is a side view showing the tuyere care device of FIG. 4 in a partial cross section.

FIG. 6 is a plan view showing the tuyere care device of FIG. 5 omitting an upper tuyere upper metal push-up head.

FIG. 7 is a diagram for explaining the operation of the blade of the tuyere care device of FIG. 4;

FIG. 8 is a view showing types of cutting tools of the tuyere care device of FIG. 4;

FIG. 9 is a view showing a lifting / lowering mechanism of the tuyere care device of FIG. 4, in which the right side shows a lowering position and the left side shows a raising position.

FIG. 10 is a flowchart showing a control example of the tuyere care device of FIG. 4;

FIG. 11 is an explanatory view of the operation of a metal lifting head provided on the head of the tuyere maintenance device of FIG. 4;

[Explanation of symbols]

 2 Tuyere 6 Tuyere maintenance device main body 7 Metal lifting head 11 Rotating shaft 13 Rotating cylinder 14 Revolving base 13a Head hole 16 Blade holder 16a Base 17 Blade 17a Saw blade 17b Phase shift saw blade 17c Flat blade 17d Dresser 18 Shaft 25 Hydraulic cylinder

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Norio Haruta 1 in Fujimachi, Hirohata-ku, Himeji-shi, Hyogo Nippon Steel Corporation Hirohata Works (56) References JP-A-64-5660 (JP, A) (58) Fields surveyed (Int.Cl. ⁶ , DB name) B22D 43/00 B22D 11/10 330

Claims (5)

(57) [Claims] A rotating base having a plurality of one-stages is provided around the rotating shaft in multiple stages in the vertical direction of the rotating shaft, and a base of a blade holder is pivotally supported on each of the tops of the rotating bases so as to be swingable. In each holder, the cutting tool is pivotally pivoted by a shaft so that the envelope of the entire cutting tool forms a frustoconical shape following the inner surface of the tuyere, and the cutting tool can be expanded and contracted by rotating centrifugal force. 1
A tuyere care device characterized in that a saw blade and a flat blade having different phases are provided in combination in the circumferential direction as the cutting tools on the top of a revolving base which is formed in a step and is located in a circumferential direction. 2. The tuyere maintenance device according to claim 1, wherein a dresser for finishing is provided as a cutting tool on a top portion of the revolving base which constitutes the lowermost stage and is located in a circumferential direction. 3. The tuyere care device according to claim 1, wherein the material of the blade is slightly lower in strength than the tuyere strength. 4. A turning drive means for turning the rotary shaft to turn the cutting tool, and a control device for controlling a turning speed by the turning drive means to control a maintenance ability by a turning centrifugal force, the control device comprising: 2. The tuyere maintenance device according to claim 1, further comprising a function of intermittently operating the rotation driving means to incline the rotation of the cutting tool. 5. The control device according to claim 1, wherein said control device includes a turning load measuring means, and when the turning load monitored by said turning measuring means falls below a predetermined value, a function for entering into a low-speed turning motion for avoiding damage to the tuyere surface. The tuyere care device according to claim 4, comprising: