JPH05200427A - Apparatus and method for immersion cooling of wire rods and steel bars - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent the outflow of cooling water from the end opening of the immersion type cooling pipe and to stabilize the water flow in the cooling device. [Structure] Cooling water is supplied into a cylindrical body 2 from a water supply port 10, and excess cooling water is discharged to the outside from a drainage port 7 provided in the middle of the cylindrical body 2 to fill the inside of the cylindrical body 2 with the cooling water. At the same time, when cooling the wire rods and steel bars running in the tubular body 2 in the cooling water-immersed state, the pressure air jet port 12 is formed at the end of the tubular body for injecting pressurized air toward the inside of the tubular body. A water film forming injection nozzle 11 that directly adjoins the pressure air injection port 12 and injects cooling water along a cross section substantially orthogonal to the cylindrical body 2 is formed between the pressure air injection port 12 and the filling water supply port 10. did.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cooling wire rods and steel bars, and more particularly to an immersion type cooling device.

[0002]

2. Description of the Related Art Wire rods and steel bars produced by hot rolling are cooled from a high temperature immediately after rolling to a predetermined temperature in order to improve mechanical quality and suppress scale formation. A cooling device using cold water as a medium is mainly used for this cooling, and it is required that the cooling device has a high cooling capacity and can be uniformly cooled in the outer peripheral direction, the cross-sectional direction, and the longitudinal direction.

Conventionally, as a cooling device, a spray system has been used in which cooling water is sprayed and cooled to spray.
Although there is a high cooling capacity in the vicinity of the rolled material to which high-pressure water is directly projected, other parts have insufficient cooling capacity, and there are many drawbacks such as low cooling efficiency compared to the amount of cooling water and pump power. For this reason, in recent years, cooling water is jetted toward the inside of the pipe from annular nozzles provided at both ends of the cooling pipe to form a water film that seals the opening of the cooling pipe and cools from the central portion in the longitudinal direction of the cooling pipe. Immersion cooling pipes have been used in which cooling water is filled in the pipes by partially discharging water and the rolled material is immersed in the cooling water for cooling.

According to this immersion type cooling pipe, the hot-rolled material comes into direct contact with the cooling water in the immersion state, and a sufficient contact time can be obtained. Therefore, the hot-rolled material has a higher cooling capacity than the spray type.

Therefore, various improvements have been made to improve the cooling capacity of the immersion type cooling pipe. For example,
JP-B-63-58207 and JP-B-63-58
In JP-A-208, a cooling pipe is proposed in which the cooling water flow in the pipe is improved by specifying the specifications of the annular nozzle based on the fact that the cooling capacity is greatly affected by the cooling water flow in the pipe. Also, the Japanese Patent Publication Sho 63-58
Japanese Patent Publication No. 209 proposes a cooling pipe having a high cooling capacity by specifying the specifications of the discharge port at the longitudinal center of the cooling pipe.

However, although these cooling pipes have a high cooling capacity, a large amount of cooling water flows out from both ends of the cooling pipe, and the effective replacement ratio (the drainage provided in the middle portion of the cylinder relative to the cooling water supply amount). There is also a drawback that the material to be cooled cannot be uniformly cooled because the ratio of the amount discharged from the outlet) is low. In order to improve this, the present inventor previously applied Japanese Patent Application No. 3-77485 to blow out the pressure air toward the inside of the cylinder at both ends of the cooling pipe, so that the cooling water flows out from both ends. We have proposed a cooling pipe that can suppress and evenly cool the material to be cooled.

[0007]

In the above prior art, in order to prevent the cooling water from flowing out from both ends of the cylindrical body, the cooling water has a high cooling capacity and the material to be cooled can be uniformly cooled. However, if the amount of cooling water is changed, the balance between the pressure of the enclosed air and the forming pressure of the water film flow is disturbed, and stable water film flow cannot be formed.

Therefore, an object of the present invention is to provide excellent balance between the enclosed air pressure and the forming pressure of the water film flow even when the amount of cooling water is changed, and thus has a high cooling capacity to cool the material to be cooled. It is to be able to do it uniformly.

[0009]

In order to solve the above-mentioned problems, cooling water is supplied into the cylinder through a water supply port provided in the cylinder, and excess cooling water is drained in the middle of the cylinder or further. In an immersion cooling device that fills the inside of the cylinder with cooling water by discharging it from the opening at the end of the cylinder to form a stable water flow, and cools the wire rods and steel bars running in the cylinder in the cooling water immersion state. , The filling water inlet,
A pressure air injection port for injecting pressure air toward the inside of the cylinder at the end of the cylinder and at least the cylinder directly adjacent to the pressure air injection port and between the filling water inlet and the cylinder. The problem can be solved by having a water film forming nozzle that injects cooling water along a cross section orthogonal to each other.

As a method, cooling water is supplied into the cylinder through a water supply port provided in the cylinder, and excess cooling water is discharged from a drain port provided in the middle of the cylinder or further through an opening at the end of the cylinder. In the immersion cooling method in which the cylinder is filled with cooling water by discharging to form a stable water flow, and the wire rods and steel bars running in the cylinder are cooled in a cooling water immersion state, from the filling water supply port. While filling the inside of the cylinder with the cooling water, the pressure air is injected from the pressure air injection port formed at the end of the cylinder toward the inside of the cylinder to substantially prevent the cooling water from flowing out from the end opening of the cylinder. Suppressing and injecting cooling water from a water film forming nozzle substantially along a cross section orthogonal to the cylinder between the pressure air injection port and the filling water supply port to form a water film on an orthogonal cross section. The discharge pressure of the pressure air Discharge pressure from the filling water supply port <can be solved by that the relation between the discharge pressure from the nozzle for water film formation.

[0011]

By supplying cooling water into the cylinder through the water supply port provided in the cylinder and discharging excess cooling water to the outside through the drain port provided in the middle of the cylinder or further through the opening at the end of the cylinder. By filling the inside of the body with cooling water to form a stable water flow, it is possible to cool the wire rods and steel bars running in the cylinder in the cooling water immersed state.

Further, in the present invention, particularly in this type of immersion cooling device, pressure air is jetted toward the inside of the cylinder from the filling water supply port at the end of the cylinder. Therefore, the cooling air that fills the inside of the cylinder flows out from the end opening of the cylinder, as if the pressure air forms a curtain,
As a result, the outflow of cooling water is prevented or suppressed, and the water is exclusively drained from the drain port. As a result, the effective replacement ratio of the cooling water in the cylindrical body is increased, the cooling capacity is improved, and uniform cooling is performed in the outer periphery, cross section, and longitudinal direction of the rolled material as the material to be cooled.

Further, as described above, if the amount of cooling water is changed, the balance between the pressure of the enclosed air and the pressure for forming the water film flow may be lost, and a stable water flow may not be formed.
On the other hand, in the present invention, a water film is formed which directly adjoins the pressure air injection port and injects the cooling water between the filling water supply port and a cross section substantially orthogonal to the tubular body. Since the water nozzle is provided, the water jetted from this water film forming nozzle forms a water curtain, and the water film curtain disturbs the flow of cooling water flowing from the water supply port under the influence of the flow of pressure air. Can be prevented.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to specific examples shown in the drawings. FIG. 1 is a view showing an immersion type cooling pipe according to the present invention,
The submerged cooling pipe 1 includes a cylindrical body 2 arranged horizontally, a cooling water discharge port 7 communicating with the inside of the cylindrical body 2 in the middle of the cylindrical body 2, and the cylindrical body 2.
A plurality of sets of cooling water supply jackets 3, water film forming jackets 4, running water pipes 5 and 6 connected thereto, and ends further than the water film forming jackets 4 arranged alternately on the outer peripheral portion in the longitudinal direction. Jacket 8 for pressure air provided on the part side
And a pressure air supply pipe 9 connected to the pressure air jacket 8.

Further, a spray-like cooling water supply port 10 is formed on the wall surface of the cylindrical body 2 in a portion surrounded by the cooling water supply jacket 3 so as to be inclined in the axial direction of the cylindrical body 2 and toward the center side.
Are formed in a plurality of rows at predetermined intervals in the circumferential direction, and moreover, a plurality of slits (circumferentially) are formed in the outer peripheral direction of the tubular body 2 on the wall surface of the tubular body 2 surrounded by the water film forming jacket 4. A water film forming injection nozzle 11 (long in the direction) is formed orthogonal to the axis.

Moreover, the cylindrical body 2 portion surrounded by the pressure air jacket 8 has a cut-off cylindrical shape with the end portion narrowed, and the cylindrical body 2 portion is inclined to the central side of the cylindrical body and is properly placed. Shaped, preferably slit-shaped pressure air ejection nozzle 1
A plurality of 2 are formed in the circumferential direction.

The pressure of the jacket 3 for supplying the cooling water is the cylindrical body 2.
Determined by the inner diameter and length of the
A pressure of ~ 2.0 kg / cm ² is sufficient.

The cooling water supplied to the inside of the cylindrical body 2 is stored inside the cylindrical body 2, and the amount of cooling water corresponding to the excessively supplied cooling water is mainly discharged from the cooling water drain port 7. While being drained, the inside of the tubular body 2 is maintained in a filled state.

On the other hand, excess cooling water is discharged from the drainage port 7 and also flows out through the opening of the cylindrical body 2 to the outside so that the effective replacement ratio of the cooling water becomes low. It is prevented by the pressure air from the jet nozzle 12, preferably 3 kg / cm ² or more, more preferably 4 kg / cm ² or more.

That is, when pressure air is ejected from the pressure air ejection nozzle 12, an air curtain is formed inside the end portion of the cylindrical body 2, and this air curtain causes
The filled cooling water is prevented from flowing out from the end opening of the cylindrical body 2. As described above, the end portion of the tubular body 2 is preferably tapered, and in this case, the opening area of the tubular body 2 is 2/3 or less, preferably 1/2 or less of the cross-sectional area of the central portion. Is.

If the balance between the enclosed air pressure and the water flow forming pressure is lost inside the cylindrical body 2, a stable water flow cannot be formed and effective cooling cannot be performed. In particular, pressurized air cannot completely eliminate pressure fluctuations due to mechanical elements of the compressor. Therefore, in the present invention, the water film forming jacket 4 is provided on the end side of the cooling water supply jacket 3 so that the film-like water flow is generated from the water film forming injection nozzle 11. This allows
The influence of the pressure air from the pressure air jet nozzle 12
The curtain effect due to the film-like water flow from the water film forming injection nozzle 11 prevents the water flow from the cooling water supply port 10 to the drain port 7 from reaching.

In the above embodiment, the water film forming injection nozzle 11 and the cooling water supply port 10 are alternately arranged in this order from the end.
Although a set is formed, the number of sets can be appropriately selected depending on the desired length of the tubular body 2. Further, as the amount of cooling water increases, the length of the cylindrical body 2 surrounded by the cooling water supply jacket 3 is made longer, and the water film forming jacket 4 is only the outermost end, which is more effective. A water film is formed.

Further, the discharge pressure of the pressure air P1≈
It is preferable that the discharge pressure P2 from the filling water supply port <the discharge pressure P3 from the water film forming nozzle. in this case,
[P3- (P1 or P2)] ≦ ± 1.0 kgf / cm
² is preferred. Further, as θ in the figure, 90 degrees to 80 degrees
Degree is preferred. The slit width of the jet nozzle is preferably 2.5 to 5 mm for forming a water film.

(Examples) The effects of the present invention will be described below with reference to examples. As shown in FIG. 2, in the process of cooling the wire rod 13 continuously running at 100 m / min in the heating furnace 14 and then cooling it with the cooling pipe 1, the immersion side cooling pipe 1 has an inlet side and an outlet side not The temperature of the uppermost point (measurement point A) and the lowermost point (measurement point B) of the wire rod 13 was measured by the contact thermometer 15 to investigate the variation in the temperature of the wire rod. Immersion type cooling pipe 1
The inner diameter is 32 mmφ and the length is 1000 mm, and the pressure of the cooling water from the cooling water supply port 10 in FIG. 1 and the pressure of the cooling water of the water film forming injection nozzle 11 are set to 1.5 kg / cm ² . The pressure of air from 12 was set to 3 kg / cm ² . In addition, as a comparative example, the test was conducted also in the case of using the immersion type cooling pipe without the water film forming injection nozzle. The test results are shown in Table 1.

[0025]

[Table 1]

From Table 1, it can be seen that in the case of the present invention example, the distribution range of the outlet temperature at both measuring points A and B is narrower than that of the comparative example, and the cooling is performed uniformly in the outer peripheral direction, the cross sectional direction and the longitudinal direction. ..

[0027]

As is clear from the above description, according to the present invention, even if the amount of cooling water is changed, the balance between the enclosed air pressure and the water film flow forming pressure is excellent and a high cooling capacity is achieved. Therefore, the material to be cooled can be uniformly cooled.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an immersion cooling pipe according to the present invention.

FIG. 2 is a schematic diagram of test equipment in an example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Immersion type cooling pipe, 2 ... Cylindrical body, 3 ... Cooling water supply jacket, 4 ... Water film forming jacket, 5, 6 ... Flowing pipe, 7
... Drainage port, 8 ... Air jacket, 9 ... Air supply pipe, 10 ... Cooling water supply port, 11 ... Water film forming jet nozzle, 12 ... Pressure air jet nozzle, 13 ... Wire rod.

Claims (2)

[Claims] 1. Cooling water is supplied into the cylinder through a water supply port provided in the cylinder, and excess cooling water is discharged to the outside through a drain port provided in the middle of the cylinder or further through an opening at the end of the cylinder. By filling the cylinder with cooling water by forming a stable water flow, the wire rod running in the cylinder, in the immersion cooling device for cooling steel bars in the cooling water immersion state, the filling water inlet, and of the cylinder A cross section that is substantially orthogonal to the cylinder between the pressure air injection port that injects pressure air toward the inside of the cylinder at the end portion, and at least directly adjacent to the pressure air injection port, and the filling water supply port. An immersion cooling device for wire rods and steel bars, comprising: a water film forming nozzle for injecting cooling water along the wire. 2. Cooling water is supplied into the cylinder through a water supply port provided in the cylinder, and excess cooling water is discharged to the outside through a drain port provided in the middle of the cylinder or further through an opening at the end of the cylinder. In the immersion cooling method in which the cylinder is filled with cooling water to form a stable water flow, and the wire rods and steel bars running in the cylinder are cooled in the cooling water immersed state, the cooling water from the filling water inlet is used. While filling the inside of the cylinder, it injects pressure air toward the inside of the cylinder from the pressure air injection port formed at the end of the cylinder, and substantially suppresses the outflow of cooling water from the end opening of the cylinder. Forming a water film on an orthogonal cross section by injecting cooling water from a water film forming nozzle along a cross section substantially orthogonal to the tubular body between the pressure air injection port and the filling water supply port, Air discharge pressure ≒ from fill water inlet Wire, wherein the discharge pressure <it has a relationship of the discharge pressure from the nozzles for water film formation, immersion cooling method of steel bar such.