JPS649558B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to vertical or inclined furnaces, such as blast furnaces, electric furnaces, special smelting furnaces, ladle or lime shaft furnaces, which are tall and have an approximately cylindrical cross-section of the furnace inner wall, and which are used in the steel industry. The present invention relates to a device for repairing a refractory-lined inner wall by spraying, and particularly to a device for repairing a furnace in a hot state without completely shutting down or cooling the furnace.

As is well known, the lining refractories of the above-mentioned various types of furnaces are locally worn out or fallen off during the later stages of operation or after multiple uses.In order to extend the service life of the furnace, parts of the inner wall of the furnace are repaired (also called intermediate repairs). ) is being carried out.

Traditionally, repairs to the inner wall of a furnace can be broadly divided into two types: those that involve a worker entering the furnace after the furnace has completely stopped operating or being used, and waiting for it to cool down, and those that involve repairing the furnace while it is in operation or temporarily suspended. There are two methods: one done from outside.

In the former case, after discharging the charges inside the furnace and waiting for the furnace body to cool, a worker enters the furnace and picks up the repair materials.
Equipment, etc. are brought in, the furnace is constructed and refractories are sprayed, and the refractory is dried and the temperature inside the furnace is raised before restarting operations, which takes a long time from shutdown to normal operation. Not only that, but the heat loss during this process is also large, and the poor working environment poses problems for maintaining the health and safety of workers.

On the other hand, the latter repair method, which is performed hot from outside the furnace, has the advantage of being able to perform repairs without completely stopping the operation and use of the furnace, but on the other hand, it is difficult to repair the furnace when the height is 10 m or more, especially when the height of the shaft alone is 20 m, such as in a blast furnace. If the diameter is more than 10 meters, when repairing the furnace, cut out the shell of the furnace body and the furnace wall, install a large manhole for the work, insert the spray nozzle of the repair material through these openings, and spray it manually. Repair work is being carried out. In this case, since the area that can be sprayed from one opening is limited, it is not preferable to maintain the strength of the furnace body, which requires providing a large number of manholes in order to carry out the entire required repair area.

In addition, there is a lot of rebound loss of the sprayed repair material due to construction constraints, and there is also a lack of accuracy in determining the repair location and construction details, resulting in a lack of spraying accuracy and construction reliability, so much can not be expected to extend the life of the furnace wall. In addition, since a large number of workers are required, the productivity of spraying work is low at around 2 to 4 tons per man-hour.Furthermore, it is necessary to install work decks around the furnace body, open and close large manholes, and carry out long spraying operations. It has many drawbacks, such as requiring complicated work such as inserting and removing the attached nozzle into the furnace, and in addition, it involves high-temperature, heavy-duty work that poses health and safety problems for workers.

Further, if the spraying machine is tall or vertical, there is a problem that it cannot be inserted into the furnace through a manhole provided in the furnace wall.

Another method is to make a small opening from the outside of the furnace at the part of the furnace wall that is believed to be damaged, insert a press-in nozzle through this narrow opening, press-fit the monolithic refractory press-in material with a predetermined viscosity, and dry and solidify it. Although repairs are being carried out, the problem is that the work cannot be done effectively because it is difficult to accurately assess the location and status of damage to the furnace wall from outside the furnace.

On the other hand, as a device for spraying refractories onto the inner wall of a furnace, for example, Japanese Patent Publication No. 53-2602 ``Refractory Material Spraying Device'' is well known. That is, a blowing device 10 is suspended above the opening of the furnace from a trolley hoist 12 on which an operator rides, and a refractory supply conduit 34 is connected to the device 10.
and a water supply conduit 30 are connected, and the spraying material mixed in a mixing head 58 inside the device is ejected from a nozzle 26 provided at the tip of the jet conduit 22. The nozzle rotation mechanism allows the nozzle to oscillate at a horizontal angle of approximately 45 degrees relative to the furnace inner wall, and the nozzle 26 itself can also rotate an additional 45 degrees around the furnace axis, so it is possible to eliminate roughness on the furnace wall. Although it is possible to control the directional spraying of repair material to the area where the repair material is to be sprayed, it is difficult to spray the repair material over a wide area and continuously around the entire circumference of the furnace wall. Since there are limits to monitoring and understanding, it is difficult to ensure the accuracy of construction, and since the spraying machine is vertically long, there are problems in that it cannot be charged into the furnace through a manhole installed in the blast furnace wall or the like.

Furthermore, in recent years, a refractory spraying device has been introduced into the furnace to carry out hot spraying repair, for example, Japanese Patent Publication No. 14728/1983, ``Blast Furnace Wall Hot Repairing Device''
describes a mechanism for spraying monolithic refractories by directing the spray nozzle 7 to a desired position and direction and rotating it along the inner wall of the furnace;
Publication No. 57-14729 “Hot repair device for blast furnace walls”
Regarding the pantograph mechanism 5 and associated mechanisms, a hot spraying repair device that is different from, but almost the same as, the previous issue is explained, but in both cases it is difficult to grasp the location of the damage and its situation, and the spraying It is difficult to perform precision control or automatic control to accurately carry out the work according to a predetermined pattern, and this has the disadvantage that not only is repair material used in vain, but also that it is difficult to ensure the reliability of the repaired wall. .

As mentioned above, although there are many drawbacks to repairing the inner walls of tall furnaces such as blast furnaces, at present no effective repair method or repair device has been developed to solve these problems.

This invention solves the various drawbacks of the conventional method, and
This system allows a small number of people to accurately and automatically repair the inner walls of tall furnaces, especially in hot conditions, without having to open new manholes, while accurately understanding the location and condition of damage and the status of the repair work. The purpose of the present invention is to provide a hanging type spray repair device that can be used. The present invention provides an apparatus for repairing the vertical or inclined refractory-lined furnace inner wall of a tall furnace with a substantially cylindrical cross section by spraying monolithic refractory in a hot state. It houses a spray nozzle with a water ring attached to the base end of the nozzle, a horizontal rotation device for the spray nozzle that can freely rotate 360 degrees, and detection equipment such as a television camera, thermometer, and furnace wall residual thickness measuring device. A spraying machine with a flat shape and a heat-resistant structure equipped with a cooling box is suspended from a traveling lifting device above the furnace using four wires via a drive device outside the furnace and a wire sheave, and each is also insulated. Covered repair material pressure hose, additive water hose, cooling water hose,
Connects cooling air hoses, power, and control cables, raises and lowers the spray machine, rotates the spray nozzle, rotates pattern and speed, pumps repair material and water, measures temperature inside and on the furnace wall, and monitors television. This is a hot spraying repair device for refractories characterized by being equipped with a control mechanism incorporating a detector and a display that operate outside the furnace.

In other words, this repair device is a type that is suspended inside the furnace, and the spray machine moves vertically up and down inside the furnace, and the spray nozzle rotates horizontally. The spray repair method maintains a constant distance between the furnace wall and the furnace wall, and the work is precisely controlled using various detectors.

The following description will be given based on the embodiment shown in the drawings. First, FIGS. 1 to 3 are a plan view, a side view, and a front view showing an example of the spraying machine of the repair apparatus of the present invention. In the figure, 1 is a horizontally long stand, 2 is the installation part of the spray nozzle, and 3 is the spray nozzle horizontally.
360 degree rotation device, 4 is a TV camera,
A cooling box houses detection equipment such as a radiation thermometer and a laser beam residual thickness measuring device, and 5 is a floodlight that illuminates the inner wall of the furnace, which is oriented in the direction of spraying from the spray nozzle like the detector and is installed on the pedestal 1. Since it is attached to the spray nozzle, it can rotate 360 degrees.

As shown in the figure, the main body of the spraying machine has a horizontally elongated flat shape as the various devices and equipment are arranged side by side to reduce the height, and its height is 730 mm.
mm, length 1800mm, width 850mm. Therefore, it can also be inserted into the blast furnace through the movable armor opening. In addition, the horizontal rotation device 3 and the cooling box 4 are coated with heat insulating material, water-cooled, air-cooled, etc., as will be described later.
It has a heat-resistant structure that allows it to operate normally even when the furnace temperature is as high as 600℃.

Next, the above-mentioned spraying machine has four hanging fittings 6a, 6.
b, 6c, and 6d, and are suspended horizontally by four wire cables, and are moved and lowered by being connected to a traveling lifting device, such as a trolley hoist, installed at the upper part of the furnace. Note that in order to adjust the extension of the hanging wire cable, it is desirable to attach a turnbuckle to the connection part with the mounting bracket 6.

Next, 7 is a repair material pressure supply hose connected to the spray nozzle through the spray nozzle attachment part 2 at the lower part of the spray machine. Reference numeral 8 denotes a hose for pressure-feeding water added to the repair material, and is connected to a water ring 9 (a mixing part of material and water) provided near the base end of the spray pipe attachment part 2. 10 and 10a are cooling water hoses that are connected to the cooling box 4 and circulated around its outer circumference for cooling.
is going, and 10a is returning. Reference numeral 11 denotes a cooling air hose, which serves to feed cooling air into the inside of the turning device 3 and the cooling box 4 to lower the temperature. The outside of the rolling device 3 is insulated with four layers of asbestos material. 12 is a power cable, 13 is a control cable, and both cables are connected to the horizontal winding device 3, the floodlight 5, and the television camera and thermometer in the cooling box 4.
The cables that operate and control the laser residual thickness measuring device are placed inside an insulated steam hose, and the inside is cooled by air pressure.

As described above, both the spraying machine and the cables connected thereto have a heat-resistant structure, so that work can be performed in the heat of the furnace.

In addition, the spraying machine is balanced in a hanging position by a balance weight 14, and is further suspended by four wire cables, so the suspension stability is good and the spraying machine does not tilt or twist. There is extremely little reaction from the material pressure of the nozzle or lateral vibration due to its rotation, and the directivity of the tip of the spray nozzle and the accuracy of the spray distance can be maintained.

In addition, the location where the repair material and added water were traditionally mixed was not at the spray nozzle section, but at the repair material pressure-feeding hose section in front of it, but the mixing location has a high correlation with the adhesion rate to the sprayed wall. However, if the mixing position is too far from the nozzle tip, the viscosity of the water and spray material mixture will increase excessively, causing instability in the flow of the spray material within the system and, in turn, unstable discharge conditions. Sometimes they become occluded and the adhesion rate decreases. In addition, it was found that if the nozzle is too close to the tip, mixing is insufficient, rebound loss increases, and the adhesion rate decreases, so in this invention, the water ring (mixture)
By attaching No. 9 to the base end of the spray nozzle, the adhesion rate of the repair material could be improved.

Next, FIG. 4 is a longitudinal sectional view showing the internal structure of the rotating device 3 for the spray nozzle. In the figure, 15 is an outer frame of the rotating device, and 16 is a heat insulating material surrounding the side of the device to protect the device from radiant heat from the furnace wall. 17 is a geared motor whose deceleration rotation is sprocket 18
→ Chain → The speed is further reduced by the sprocket 19, and the final speed is reduced by the reducer 20 and reduction gears 21 and 22, so the rotation of the reduction gear 22 is 0.15 ~
It becomes 0.46rpm. This rotation is transmitted to a hollow rotating shaft 24 provided on the spray nozzle support plate 23.
On the other hand, a wear-resistant tube 25 connected to the lower end of the material hose 7 and having an inner surface coated with ceramic, a seal pusher 26, a bearing 27, and a gland packing 28 constitute a seal joint.
The cheese 29, which freely rotates coaxially with the tube 25 and is fixed to the spray nozzle support plate, is connected to the tube 2.
5, the spray nozzle connected to its tip can freely rotate 360 degrees regardless of the outer frame 15 and material pressure hose 7. Note that the spraying speed of the spray nozzle can be converted to a predetermined speed using a frequency converter.

Next, FIG. 5 is a vertical cross-sectional view showing an example of the internal structure of the cooling box 4 shown in FIGS. Radiation thermometer, 34
is a laser beam receiver. The laser beam emitting/receiving devices 31 and 34 are furnace wall remaining thickness measuring detectors for measuring the degree of damage to the furnace inner wall.

Reference numeral 35 denotes a cooling water hose introduction connection, and the cooling water circulates around the entire outer surface of the cooling box except for the front opening, and is recovered to the outside from the cooling water discharge hole 35a. Reference numeral 36 denotes a connection part of a cooling air hose, and the cooling air circulates inside the box, cools the entire outer surface of each detection device installed inside, and is discharged outside the box. This discharge also serves as an air purge for dust prevention. Further, numeral 37 is a small window made of dust-proof glass provided on the front side.

Since the cooling box 4 has such a structure,
The internal detectors operate normally without being affected by temperature up to 600℃. Note that a thermocouple thermometer can be installed near the cooling box to measure the atmospheric temperature inside the furnace.

Next, the spraying repair work when the repair device of the present invention is installed in a blast furnace will be explained. Fig. 6 is a side view showing an example of installation; in the figure, 38 is the shell of the blast furnace; 39 is the inner wall of the furnace lined with refractory material;
40 is a damaged part of the inner wall, 41 is a movable armor manhole, and 42 is a work deck. Regarding the charges inside the blast furnace, the upper row shows the raw material level during operation, the middle row shows the reduced-scale operation raw material level during shaft upper spray repair, and the lower row shows the reduced-scale operation raw material level during shaft lower spray repair.

In order to charge the spraying machine 43 into the furnace where the blast furnace materials have been reduced to a predetermined level, the boom traveling device 44 retracted outside the furnace is moved in front of the movable armor manhole 41 using a crane or the like. After moving and fixing it onto a nearby work deck 42, the traveling motor 45 is activated to extend the moving boom 46 into the furnace. At this time, by inserting the spraying machine 43 into the furnace in close contact with the lower surface of the movable boom 46, the flat-shaped spraying machine can pass through the manhole.

Extension of the boom is stopped by a limit switch attached to the boom, and the spray machine can be accurately positioned at the center of the furnace axis as shown in the figure. There are also four wires 4 hanging the spraying machine 43.
7a, 47b, 47c, and 47d are connected to the lifting drum 49 via the wire sheep 48, so by operating and adjusting the lifting motor 50, the spraying machine is lowered to the level of the inner wall of the predetermined repair position. It can be stopped and, if necessary, the horizontal position of the spray machine can be detected and corrected.

Since the spray nozzle 51 attached to the spray machine 43 can freely rotate 360 degrees around the reactor core, it can be connected to any part of the entire circumference of the reactor wall while keeping the distance between the tip of the spray nozzle and the inner wall constant. Can be swiveled at an angle to perform spray repairs.

The material and water pressure feeding hose 52 connected to the spraying machine is connected to a hose guide 53 and a hose winding device 54.
The compressor 57 is connected to a repair material supply device 55 and an additive water pump 56 through the compressor 57, and a hose of a compressor 57 is connected to the material supply device, and its drive provides the necessary pressure for spraying. , the repair material is ejected from the spray nozzle 51. Note that 58 is an information processing and control device.

When the tip of the spray nozzle is fixed at a predetermined spraying position, a monolithic refractory (repair material) of a predetermined composition is put into the hopper of the repair material supply device 55 and spraying starts. For spraying construction, the atmospheric temperature inside the blast furnace
It can be carried out at a hot temperature of 300 to 600℃ and a furnace wall temperature of 200 to 400℃, and usually repairs a large number of areas that require repair, which are determined based on the damage to the inner wall measured in advance using a laser residual thickness measuring device. The method is divided into sections, and construction is carried out in each section using a spraying pattern that sets the rotation span, lifting pitch, and lifting span of the spray nozzle. Also, at this time, the amount of water to be added is set in accordance with the surface temperature of the furnace wall, based on data on the relationship between the furnace wall temperature and the water added to the repair material obtained in advance, and construction is started.

On the other hand, by storing the laser residual thickness measurement results in a computer, spraying can be performed automatically by operating each mechanism according to commands from the computer.

Therefore, the spray nozzle sprays the repair material by ascending or descending at a predetermined position while oscillating at a predetermined angle, then moves to the adjacent construction area, continues to oscillate, and moves sequentially. During this time, the degree of damage to the repaired wall and the spraying status of the repair material can be monitored using a television camera, and the swing speed and spray pressure of the spray nozzle can be finely adjusted.

This repair device simultaneously and accurately detects the vertical position of the spray machine, that is, the vertical position of the spray nozzle, and controls its vertical speed, as well as detects the horizontal rotation position of the spray nozzle and controls its rotation speed. Importantly, these are detected and actuated by encoders for detecting the lifting and swivel positions (installed on the lifting and swivel equipment, respectively) and the VVVF motor for adjusting the speed, and automatically controlled by the computer. It has a controlled structure. FIG. 7 schematically shows an example of the mechanism and control method for elevating and turning.

The drive motor uses a VVVF motor to raise and lower the spray nozzle, so the spray pattern can be selected depending on the situation, such as vertical swing up and down movement or vertical swing left and right movement. can.

When the upper part of the shaft is turned in this manner, the level of the raw material to be introduced into the furnace is further lowered and the lower part of the shaft is constructed. In this case, the spraying machine 43 is lowered to the position shown in the diagram, so the hanging length reaches approximately 18 to 19 m, but as mentioned above, the hanging wire cables are suspended in a well-balanced manner using four wires. Therefore, the spraying machine does not tilt or sway during movement or during construction, and there is no possibility of it backing up due to the reaction of the spraying pressure of the repair material. Therefore, the direction of the spray nozzle and the vertical position of the tip can always be stabilized at a predetermined operating position.

Extending the boom, raising and lowering the spray machine as explained above,
Spray nozzle rotation, rotation pattern and rotation speed,
All operations such as pumping of repair materials and water, temperature measurement inside the furnace and furnace walls, and television monitoring are performed outside the furnace, and various detectors,
By providing a control mechanism with a built-in display, all operations can be performed from the operation panel. Furthermore, by setting all operation patterns in advance and inputting them into the computer, repair work can be carried out fully automatically.

Please note that the spray nozzle will wear out with use.
Replace with a new one every 20 to 30 tons sprayed. The nozzle can be easily replaced at a position where the spraying machine 43 is pulled up and stored in the movable boom 46, the movable boom is retracted, and the spraying machine is moved to the manhole 41.

When the spraying repair of the furnace inner wall is completed in this way, the spraying machine is lifted up and brought into close contact with the boom, and the boom traveling device is driven to retreat the boom outside the furnace.
If necessary, move the boom drive away from the manhole with a chain block to complete the entire operation. It should be noted that various other types of devices may be used for the installation of the spraying machine into the furnace and for moving the spraying machine up and down.

Since the repair device of the present invention has the structure as described above, it has the following effects in repair work.

1. Since repairs can be carried out hot without shutting down the furnace, normal operation can be resumed in a short period of time after repairs, which improves the furnace operating rate and energy savings.

2 Since it can be charged into the furnace through the existing opening, there is no need to change the structure of the furnace.

3 Equipment can be set up in a short time.

4. Since the damage situation can be accurately grasped and the position and operation of the spray nozzle can be precisely controlled, spraying can be carried out under optimal conditions and the service life of the repaired wall can be extended.

5. A wide range of areas from the upper part to the lower part of a large furnace can be constructed continuously in a short time.

6. The construction pattern can be set in advance and spraying construction can be performed automatically.

7. Can be constructed by two workers, dramatically improving work productivity.

8. Optimal construction can be carried out by accurately responding to the slope profile of the inner wall.

9. The working environment is good and safe.

Although the above explanation mainly concerned construction work in a blast furnace, this repair device can be applied to spraying work on the inner walls of tall circular furnaces and containers other than blast furnaces, and similar effects can be obtained. I can give it to you.

[Brief explanation of drawings]

1 to 3 are a plan view, a side view, and a front view showing an example of a spraying machine used in the present invention, and FIG. 4 is a vertical sectional side view showing an example of a rotating device of the spraying machine.
FIG. 5 is a vertical cross-sectional view showing the inside of a cooling box provided in a spraying machine, and FIG. 6 is a side view of an embodiment showing how the spraying repair device according to the present invention is used in a blast furnace.
FIG. 7 is a schematic diagram of the mechanism and control for raising and lowering the spray machine and rotating the spray nozzle. 2... Spray nozzle attachment part, 3... Swivel device, 4... Cooling box, 5... Floodlight, 6a, 6b,
6c, 6d...Hanging fittings, 7...Repair material pressure feeding hose, 8...Additional water pressure feeding hose, 9...Water ring, 10, 10a...Cooling water hose, 11...
...Cooling air hose, 12...Power cable, 1
3...Control cable, 16...Insulation material, 17...
Geared motor, 20...Reducer, 24...Hollow rotating shaft, 25, 26, 27, 28...Siebel joint, 31...Laser beam transmitter, 32
...TV camera, 33...Radiation thermometer, 34...
... Laser beam receiving device, 39 ... Refractory lining inner wall, 40 ... Damaged part of inner wall, 43 ... Spraying machine,
47a, 47b, 47c, 47d...4 hanging wires, 50...lifting motor, 51...
spray nozzle.

Claims (1)

[Scope of Claims] 1. A device for repairing the vertical or inclined refractory-lined furnace inner wall of a tall furnace with a substantially cylindrical cross section by spraying monolithic refractory in a hot state. A spray nozzle with a water ring attached to the base end of the spray nozzle, a horizontal rotation device for the spray nozzle that can freely rotate 360 degrees, and detection equipment such as a television camera, a thermometer, and a furnace wall residual thickness measuring device. A spraying machine with a flat shape and a heat-resistant structure, equipped with a cooling box containing a cooling box, is suspended from a traveling lifting device above the furnace, so that it can be raised and lowered by four wires via a drive device outside the furnace and a wire sheave. In addition, there is a repair material pressure hose, an additive water hose, a cooling water hose, each with a heat insulation coating.
Connects cooling air hoses, power, and control cables, raises and lowers the spray machine, rotates the spray nozzle, rotates pattern and speed, pumps repair material and water, measures temperature inside and on the furnace wall, and monitors television. A hot spraying repair device for refractories characterized by having a control mechanism incorporating a detector and an indicator that are operated outside the furnace.