JPS6054254A - Automatic spraying device for powder in continuous casting - Google Patents

Abstract

PURPOSE:To provide a titled device which can feed powder at a constant rate and spray uniformly the powder in a mold with a small amt. of a carrier gas with the device for spraying the powder pneumatically by providing successively a means for feeding the powder, a means for transporting the powder in suspension and a spraying nozzle. CONSTITUTION:The inside of a tank 1 is pressurized and a stop valve 3 is repeatedly opened and closed at set timings. Powder is filled approximately in a storage tank 43 by one time of such opening. The powder is discharged through a discharge port 47 and is dispersed by a conical-shaped projecting part 45, by which the powder is dropped in a dispersed state through plural holes 46. The powder in the mid-way of falling is forcibly fed in a feed pipe 5 by the pressure gas injected from an injector 7A and is fed in a suspended state. If the pipe 5 is long and the pressure drop in the pipe 5 is large, the powder is additionally fed by an injector 7B. The powder transported in suspension in the above-mentioned way is sprayed uniformly in a casting mold 10 from a spray nozzle 8 provided with plural holes or slits in the longitudinal direction of the tubular body which is provided successively to the terminal of the pipe 5 and is closed at one end.

Description

[Detailed description of the invention] [Industrial application field] The present invention is applied in a mold in continuous casting equipment.

This invention relates to an automatic powder dispersion device for supplying a fixed amount of powder using gas and automatically distributing it uniformly.

[Conventional technique pdoj]

Continuous casting machines are currently being introduced worldwide in the steel industry. In continuous casting, on the surface of molten steel in the mold that forms slabs such as slabs and blooms.

In addition to oscillation, lubrication between slab and molded copper plate,
It is also essential to supply and spray powder for the purpose of removing impurities, keeping heat, etc. In the conventional method, lubricant was manually supplied and sprinkled onto the surface of the hot water inside the mold, and the amount of spraying was based on human intuition, which resulted in individual differences, and it was not always possible to provide adequate lubrication. Also high fever and a
There was a problem that the working environment was poor due to the generation of powder dust. On the other hand, attempts have recently been made to automatically spread the powder without requiring manual intervention, and a known method is a mechanical transportation/dispersion method using a slurry feeder or the like, which has become the mainstream. However, this method requires the dispersion feeder to be installed in a narrow space between the tundish and mold, making it particularly unsuitable for small cross-sectional sizes due to the limited installation space determined by the required size of the feeder and lack of flexibility. There were problems such as poor workability around the reeds and the mold, and low reliability of the equipment due to thermal problems. A pneumatic method was also tried, but with this method,
In order to reduce the amount of pneumatic gas from the viewpoint of dust generation and cost, a plug transportation method is used, but since the powder is in the form of powder particles, the contact resistance in the feeding route is large, and if the piping becomes clogged, the compressed gas will intermittently flow through the nozzle. Yo,! 7 squirts.

This method has not been used for dispersing powder inside the mold because it stirs up the powder inside the mold and generates dust, but it is currently being used to transport powder to the next side by taking advantage of the flexibility of pneumatic conveyance. They are only fed by a spring feeder.

[Purpose of the invention]

In order to solve these issues, the present invention utilizes a pneumatic conveyance system that uses a floating transport system to enable fixed-quantity feeding and uniform dispersion of granular powder into the mold using a small amount of carrier gas, making it simple and easy to use. The purpose of the present invention is to provide a device that can perform automatic, accurate, and highly reliable powder dispersion without generating dust, and with a flexible and compact device configuration.

[Structure of the Invention] The present invention provides a powder feeding means for delivering a predetermined amount of stored powder, a powder floating transport means for transporting the delivered powder to a mold, and a powder floating transport means for transporting the delivered powder to a mold. It consists of a spray nozzle for spraying onto the surface of the mold.

〔Example〕

First, the powder feeding means will be explained.

FIG. 1 shows an overall view of the apparatus according to the present invention [(A) is for blooms and billets, (B) is for slabs], and 1 is for N2
It is a tank that is sealed to the extent that moisture absorption is prevented by blowing, and a powder 12 is stored inside, and an N2 conduit 2 is connected to the top, and N2 gas from which water has been removed is flowed from above into the powder of 1 yen in the tank. , In order to prevent the amount of powder from becoming sticky, it is also ejected from the bottom of the tank. Additionally, a load cell 6 is installed in the tank 1, making it possible to grasp the amount of powder used. Connected to the lower part of the tank 1 are an opening/closing knob 3 and an ejector 4 for continuously discharging and feeding a required amount of powder.

FIG. 2 shows a detailed sectional view of the opening/closing knob 3 and the ejector 4, and the opening/closing knob 3 is formed by a powder passage 31 and a valve 33 disposed between the passage and the frame 32. It is equipped with a conduit 35 for sending pressurized gas to the airtight chamber 34 and one nuclear airtight chamber, and a three-way solenoid valve 37 and a three-way solenoid valve 38 that open and close in response to a signal from a timer 36 shown in FIG.

The opening/closing knob 3 is operated by opening the three-way solenoid valve 37 in the incoming direction.
When the three-way solenoid valve 38 is closed, pressurized gas is introduced into each airtight chamber 34, and each valve 33 is pressed against the passage 31 as shown by the broken line in the figure.
will be closed. When the three-way solenoid valve 37 is opened in eight directions and the three-way solenoid valve 38 is opened, the pressure gas in the airtight chamber 34 is sucked outward and the valve 33 is opened. The ejector 4 includes a powder dispersion member 42 attached to a holder 41, a powder reservoir 43 screwed to the upper part of the holder 41, and a powder reservoir 43 attached to the upper part of the holder 41.
It is equipped with an injector inner tube 71 attached to the lower part of the injector. The dispersion member 42 is 'W, Figure 3 [(A) is an enlarged sectional view,
(B) is a plan view], a conical protrusion 45 is protruded from the center, and a plurality of through holes 46 are provided around the conical protrusion. The top 45a of the conical projection 45 is located at or below the lower end of the discharge port 47. 48 is a tightening nut for fixing the storage tank 43 to the holding body 41, and 49 is an OIJ for preventing outside air from entering inside the holding body 41.
There's a song.

Next, the powder floating transportation means will be explained.

In FIG. 1, 5 is a powder feeding pipe connected to the ejector 4, and 7A and 7B are injectors for feeding powder that is passing through the feeding pipe 5 or has passed through the ejector 4.

FIG. 4 shows a detailed diagram of the injectors 7A and 7B.
1 is an inner pipe, 72 is an outer pipe, and 73 is a pressure gas introduction pipe provided in the outer pipe 72. 71 is inserted,
A pressure gas passage 74 is formed surrounding the inner tube 71;
A ring-shaped nozzle 75 is formed at the tip of the passage 74 as a pressurized gas outlet. Note that the inner diameters of the inner tube 71 and the outer tube 72 are approximately the same.

Pressure gas supplied from the introduction pipe 73 passes through the ring-shaped nozzle 7
The powder 1 in the inner tube 71 is
2 is further sent to the outer tube 72. The pressurized gas ejected from the ring-shaped nozzle 75 is forced into an airflow along the inner surface of the outer tube 7゛2, so the powder sent inside the outer tube 72 is sent while being surrounded by the airflow, and is almost completely connected to the inner surface of the outer tube. There is no contact with the inward direction, and the contact resistance with the inward direction is very small. Therefore, the powder can be fed while minimizing a decrease in the powder feeding speed, and wear of the outer tube 72 and the feeding tube 5 can be prevented.

Next, the spray nozzle will be explained.

Reference numeral 81 denotes a nozzle main body, and reference numeral 82 indicates a number of discharge ports opening in the longitudinal direction of the main body.As mentioned above, such a dispersion nozzle 8 surrounds the through hole and injection nozzle 11 shown in FIG. It is located in the center.

The powder is evenly discharged from the discharge port 82 in the longitudinal direction,
It falls to the center of the hot water surface and gradually melts while moving evenly toward the inner surface of the mold 10, and by the time it reaches the mold edge, it is completely melted and supplied to the surface of the slab.

In this way, the powder is dispersed continuously at the center of the mold surface, so there is no fluctuation in powder dissolution at the mold edge.
Completely dissolved powder can be supplied at all times.

With multi-hole nozzles, if the discharge flow rate is within 1/3 bay, the same amount of powder will be sprayed directly below from each nozzle, as shown in Figure 7 (-), and will be uniformly spread over the mold surface.

Therefore, it can be said that this nozzle is suitable not only for slab slabs but also for small cross-sectional sizes or irregularly shaped slabs.

FIG. 6 is an enlarged detailed view showing another example of a dispersion nozzle (slit nozzle) [(A) is a plan view, (B) is a side view], and 8
1 is a nozzle main body, and 82 is a slit-shaped discharge port. With the slit nozzle of this example, as shown in Fig. 7 @)K, the nozzle is ejected at an angle in the nozzle feed direction, which is inconvenient for molds with small cross-section sizes, but It can be applied to molds such as Lb, and the powder can be sprayed in front of the nozzle, so it is convenient when spraying mainly around the injection nozzle where it is difficult to install the nozzle close to it.

In FIG. 1, 9 is a pressure regulator, 10 is a mold, and 11 is an injection nozzle, which are arranged at the center above the hot water surface.

In this example, the apparatus shown in FIG. 1 is provided so as to surround the injection nozzle 11.

Next, a series of operations will be explained. First, the timer 36 determines the opening/closing timing of the opening/closing valve 3 based on the amount of powder to be supplied into the mold 10 per unit time, that is, the three-way solenoid valve 37. Set the opening and closing timing of the three-way solenoid valve 3B,
In addition, the reservoir (!!i3) is equipped with a discharge port 47 having a diameter capable of discharging the desired amount of powder.Next, open the pressure gas valve 13 and switch the timer 36 (not shown). ), the pressure inside the tank 1 is increased to 11, and the opening/closing valve 3 repeats opening and closing at the set timing. By opening the on-off valve once, the storage tank 43 is almost filled with powder. The powder in the storage tank 43 is discharged from the discharge port 47, dispersed by the conical protrusion 45, and falls from the plurality of through holes 46 in a dispersed state. This falling powder is completely pumped into the feed pipe 5 by the pressure gas jetting out from the injector 7A. The powder is sent in a floating state inside the feeding pipe, but if the pipe length is long and the pressure loss inside the pipe is large, the powder inside the feeding pipe 5 is driven in by the injector 7B. In the injector 7B, the powder is drawn into the airflow that flows along the entire inner circumference of the tube along the direction of the inner surface of the tube and is transported floatingly. Therefore, ξ powder can be sent at a low speed and is evenly sprayed from the spray nozzle 8 into the mold lO. Storage tank 43
At the same time as the inside is emptied, the opening/closing valve 3 opens for a predetermined period of time and the storage tank 43 is filled with powder in the same manner as described above. (4"!'I43 is filled with powder by assembling tank 1, opening/closing] and luzo 3, but in order to prevent the reservoir tank 43 from emptying, a means that can be inserted or nailed is used. If necessary, other known means can be used.

In addition, the pressure gas can be ejected into the feed pipe by providing a pressure gas ejection port 6-1 in the feed pipe 5 as shown in FIG. But that's fine. In order to improve the flow of powder in the dispersing member 42, see FIG.
There are methods such as forming the angle θ shown in A) to be in the range of about 200 to 60 degrees, or forming the through hole 46 in the lower floor.

9 and 10 show other embodiments of the powder feeding means, in which the tank 1 is directly connected above the storage tank 43 and the opening/closing knob 3 is omitted.

The opening and closing of the disk 3 has the effect of applying a shock to the cylinder and preventing jamming due to its operation, but the disk 1 shown in Fig. 1
4. This can be omitted by increasing the action of the pressure gas ejection pipe 15 to prevent clogging of powder.

In FIG. 10, the ejector 4 is omitted and the on-off valve 3 and the injector 70 are directly connected.

In this case, the amount of powder fed is adjusted by the timing of operation of the opening/closing pulp 3.

〔Effect of the invention〕

Conventionally, powder, especially granular powder, could not be completely fed and dispersed, so most of the feeding during casting was done manually, and it was not possible to feed the appropriate amount, resulting in poor lubrication between the inside of the mold and the slab. However, the present invention can solve the above problems, suppress the wear of the feed pipe, and relieve the harsh casting work that involves high temperatures and dust. This will have a significant effect on improving the quality of slabs and the working environment.

In addition, since the configuration is simple, there is no need to worry about breakdowns, and maintenance is easy.Furthermore, it is compact and does not interfere with folding work, so it can be used not only for slab slabs but also for small cross-section or irregular shaped slabs. In addition to being more effective in some cases, it can also become a powerful means of automation and mechanization in recent years.

[Brief explanation of drawings]

Figures 1 (A) and (B) are overall cross-sectional views showing an example of rotation for carrying out the present invention, Figure 2 is a partial detailed cross-sectional view of Figure 1, and Figure 3 is a cross-sectional view of Figure 2. 4 is a partial detailed sectional view of FIG. 1; FIG. 5 is an example of a dispersion nozzle; (A) is a plan view;
(B) is a cross-sectional view of (~), FIG. Figure 10 is a sectional view showing another embodiment of the powder feeding means. 43 is a storage tank, 45 is a conical protrusion, 46 is a through hole, 47 is a discharge port, 5 is a powder feeding pipe, 6 is a nobbler 17N, 7B is an injector, 8 is a powder dispersion nozzle, 10
1 is a mold, 11 is an injection nozzle, and 12 is a chisel rag. 61 is a spout, and 75 is a ring-shaped nozzle. Agent Patent attorney Masamitsu Akizawa and 2 others Figure 3 (A) Figure 3 (B) Figure 84 Haku 50 (A) /8 Figure 7 (A) Figure 7 (B) Figure 8

Claims (1)

[Claims] (1) Powder feeding means and floating transportation means, and a dispersion nozzle equipped with a plurality of holes or slits in the longitudinal direction of the tube with the pipe closed at the end of the feeding pipe connected to the floating transportation means. An automatic powder dispersion device for continuous casting, which is characterized by being installed in series.