WO1992002645A1

WO1992002645A1 - System for continuously cooling metal strip

Info

Publication number: WO1992002645A1
Application number: PCT/JP1991/001009
Authority: WO
Inventors: Osami Yoshioka; Hiroaki Sato; Kouji Omori; Masayuki Yamazaki; Masafumi Suzuki; Hitoshi Oishi; Naoto Kitagawa; Takaya Seike; Yasuhiro Araki
Original assignee: Nkk Corporation
Priority date: 1990-07-31
Filing date: 1991-07-26
Publication date: 1992-02-20
Also published as: BR9105852A; DE69123038T2; JPH0488128A; JP2592175B2; ATE145012T1; EP0495115B1; KR920702428A; EP0495115A4; ZA915774B; ES2096656T3; EP0495115A1; DE69123038D1; KR950004711B1

Abstract

A system for continuously cooling a metal strip which comprises at least one cooling roll rotatable and in contact with the metal strip, for cooling the metal strip continuously moving in the lengthwise direction thereof, said cooling roll allowing a cooling liquid to flow therethrough for continuously cooling said cooling roll, and a contact area between the surface of said cooling roll and the surface of the metal strip being controllable; a gas cooling machine disposed at the outlet of said cooling roll, for continuously cooling the metal strip by blowing the cooling gas onto the metal strip in such a manner that the distribution of temperature in the direction of a plate width of the metal strip is kept uniform after the final cooling, said gas cooling machine including a plurality of nozzle headers being independent of one another, for blowing the cooling gas onto the metal strip, and said plurality of nozzle headers controlling at least one of the flowrate and the flow velocity of the cooling gas in the direction of the plate width of the metal strip; a first tension adjusting machine disposed at the inlet of the said cooling roll; and a second tension adjusting machine disposed at the outlet of the gas cooling machine.

Description

Description Name of Invention

Continuous cooling system for metal strip

The present invention relates to an apparatus for continuously cooling a metal strip that is continuously moving in its length direction so that the temperature distribution in the sheet width direction is uniform. It is. Background art

For example, continuous annealing of metal strips, such as steel strips, tabs, etc., is performed as follows: a metal strip moving continuously along its length. The tip is heated to a predetermined temperature and then soaked. Next, the metal strip, which has been heated and soaked in this manner and is continuously moving in its length direction, is immediately or gradually cooled to a predetermined temperature and then cooled to a predetermined temperature. At the cooling rate, the gun is cooled down to the specified temperature. Next, the metal strip thus cooled is continuously subjected to an overaging treatment or a tempering treatment.

Water cooling, gas cooling, and roll cooling are known as methods for cooling metal strips in the above-described continuous annealing treatment. Of these cooling methods, the roll cooling method has the advantage that the metal strip can be rapidly cooled to a desired temperature. ing. Therefore, in this respect, the roll cooling method is superior to the water cooling method and the gas cooling method.

As a device for continuously cooling a metal strip by a roll cooling method, for example, Japanese Patent Publication No. 57—14 dated March 24, 1998 , 414 disclose a continuous cooling system for metal strips consisting of:

A plurality of free-rotating cooling rolls that contact the metal strip for continuously cooling the metal strip moving continuously in its length direction; Each of the plurality of cooling rolls has at least the same length as the width of the metal strip, and each of the plurality of cooling rolls has the same length. The axes are parallel to each other, and a coolant flows inside each of the plurality of cooling rolls to continuously cool each of the plurality of cooling rolls. And at least one of the plurality of cooling rolls is provided for controlling a contact area between a surface thereof and a surface of the metal strip. It can be displaced toward the metal strip (hereinafter referred to as "prior art 1").

FIG. 35 is an explanatory view showing an example of a continuous cooling device for a metal strip, for example, a steel strip, according to the above-mentioned prior art 1. As shown in Fig. 35, the free-rotating free-rolling steel strip 1 contacts the steel strip 1 to continuously cool the steel strip 1 moving continuously in its length direction. For example, a plurality of cooling rolls 2 composed of five rolls 2a to 2e are arranged at predetermined intervals with their axes parallel to each other. Each of the cooling rolls 2 has at least the same length as the width of the steel strip 1, and the coolant flows through the inside of the cooling roll 2. The cooling roll 2 is continuously cooled. In order to control the contact area between each surface of the cooling roll 2 and the surface of the steel strip 1, each of the cooling rolls 2 is driven by a drive mechanism (not shown). Displaceable towards net strip 1

0

The strip 1 continuously moves in the direction indicated by the arrow in FIG. 35 while contacting each of the plurality of cooling rolls 2 described above. In the meantime, a portion of the surface of the steel strip 1 that contacts each surface of the cooling roll 2 is cooled. The contact area between the surface of the sales strip 1 and the surface of each of the cooling rolls 2 is such that each of the cooling rolls 2 is displaced toward the net strip 1. Is controlled by Thus, the mesh strip 1 is continuously cooled to a predetermined temperature by the plurality of cooling rolls 2.

The above-mentioned prior art 1 has the following problems: immediately, the net strip 1 moving in a gun-like manner in the length direction is subjected to the temperature distribution in the width direction of the plate. In order to cool the steel strip 1 continuously so that the temperature is uniform, the surface of the steel strip 1 and the surface of each of the plurality of cooling rolls 2 must be It is necessary to make uniform contact in the width direction of the board.

However, the surface of the strip 1 and the surface of each of the plurality of cooling rolls 2 are evenly arranged in the width direction of the steel strip 1. Adhering to — is difficult for the following reasons:

(1) When the strip 1 comes into contact with each of the plurality of cooling rolls 2, the strip 1 applies the respective cooling rolls 2 to each of the plurality of cooling rolls 2. As a result, a saddle-like deformation occurs in the width direction of the strip 1 as a result of being bent into an arc shape.

(2) In steel strip 1, there are variations in the thickness in the width direction, poor shape, and uneven tension in the width direction.

(3) Due to the contact with the high-temperature steel strip 1, each of the plurality of cooling rolls 2 generates a roll crown due to thermal deformation.

(4) The surface roughness of each of the plurality of cooling rolls 2 is uneven

Therefore, particularly, the surfaces of the steel strip 1 at both ends in the sheet width direction are hardly in contact with the surfaces of the plurality of cooling rolls 2.

FIG. 36 shows an example of a case where the strip 1 is continuously cooled using the cooling device according to the prior art 1 shown in FIG. 35 under the following conditions. This is a graph showing the temperature distribution of Strip 1 in the width direction.

(1) Thickness of steel slip 1: 1.2mm,

(2) Strip 1 width: 1,200mm,

(3) Cooling start temperature of steel strip 1: About 600,

(4) Target cooling temperature of steel slip 1: 350

(5) Chemical composition of steel strip 1: As shown in Table 1, Table 1

(wt. ¾)

In FIG. 36, the horizontal axis represents the distance from one end of steel strip 1 to the center in the width direction of the steel strip 1, and the vertical axis represents the steel strip. 1 shows the temperature in the sheet width direction.

As shown in Fig. 36, the temperature in the width direction of the steel strip 1 at the exit side of the cooling roll 2e is from one end of the steel strip 1 to about lODraiD. In this part, the target cooling temperature is exceeded, for example, about 570 at a position 20HHD from one end of steel strip 1 and lOOfflm from one end of the steel strip 1. In the position, it is about 350. As described above, the temperature distribution in the width direction of the steel strip 1 on the exit side of the cooling roll 2e is higher at the both end portions than at the central portion, and is uneven. And the temperature difference between its center and one end is about 220. As a result, shape defects such as ear waves and apertures occur in steel strip 1 after roll cooling. As described above, when the ear wave is present at the side end of the steel strip 1, the next processing step performed on the steel strip 1 after the roll cooling, for example, overaging is performed. In the treatment process, abnormal movement such as meandering occurs in the steel strip 1 that moves continuously in the length direction. As a result, in extreme cases, steel strip 1 breaks, making operation impossible. Therefore, in the next processing step, the moving speed of the steel strip 1 after the roll cooling has to be slowed down, and the operating efficiency is greatly reduced. Furthermore, if there is a restriction in strip 1, the steel strip becomes defective. Therefore, the product yield decreases.

Fig. 37 shows that the above-mentioned strip 1 was overaged at 350 ° C for 2 minutes, then temper rolled at 1.5% reduction, and then 100%. This is a graph showing the aging index (AI) in the width direction of Strip 1 when aging treatment is performed at all temperatures for 60 minutes. In FIG. 37, the horizontal axis represents the distance from one end of the steel strip 1 to the center in the sheet width direction, and the vertical axis represents the steel strip. 1 shows the aging index (AI) in the sheet width direction.

Due to the increase of the yield point of steel strip 1 due to aging, 1 strip 1 has poor shape during press working, spring back, and yield Point elongation and deterioration of buckling resistance occur. The extent of these occurrences differs in the width direction of steel strip 1.

Therefore, a paste having the dimensions and the chemical composition described above is used. Assuming that the upper limit of the aging index (Ι される) at which the yield point elongation does not occur during blessing in Lip 1 is, for example, 4 kgf / dragon ² , it can be seen from FIG. 37. , the aging措数portion to one edge or found about 90 IDID steel be sampled Clip 1 is higher than the 4 Kg f / rara ²

. Therefore, the mechanical properties of the net strip 1 in the width direction become uneven.

As a device for continuously cooling a steel strip by a roll cooling method to solve the above-mentioned problem, Japanese Patent Publication No. Ha 2-274, 822 discloses a steel strip gun cooling system comprising:

A plurality of cooling rolls that are free to rotate and that contact the mesh strip for continuously cooling a steel strip moving in a continuous manner in its length direction; Each of the cooling rolls has at least the same length as the plate width of the steel strip, and the axes of the plurality of cooling rolls are mutually aligned. Parallel, and a cooling fluid flows inside each of the plurality of cooling rolls to continuously cool each of the plurality of cooling rolls; and

Cooling gas is blown onto the surface of the mesh strip so that the temperature distribution in the width direction of the steel strip after the final cooling is uniform. A gas cooler disposed on the outlet side of the plurality of cooling rolls for continuously cooling the mesh strip; and At a predetermined distance from each of both surfaces, the plate of the strip The gas cooler is arranged in a width direction, and is provided with a plurality of mutually independent nozzle headers for spraying the cooling gas onto the surface of the strip. In addition, the plurality of nozzle headers are configured to reduce at least one of the flow rate and the flow rate of the cooling gas to a width of the strip. Direction (hereinafter referred to as “prior art 2”).

FIG. 38 is an explanatory diagram showing an example of a continuous cooling device for a steel strip according to Prior Art 2 described above. As shown in FIG. 38, a plurality of strips having the same structure as described in the prior art 1 for continuously cooling the strip 1 moving continuously in its length direction are provided. The cooling rolls 2 are arranged at predetermined intervals with their axes parallel to each other. On the exit side of the plurality of cooling rolls 2, a gas cooler 3 is provided at a predetermined distance from each of both surfaces of the steel strip 1 which moves continuously in the length direction. In addition, they are arranged in the width direction of steel strip 1.

FIG. 39 is a schematic perspective view showing an example of a gas cooler 3 used in the cooling device according to Prior Art 2. As shown in Fig. 39, the gas cooler 3 has a plurality of nozzle headers 4 independent of each other for blowing cooling gas onto the surface of the steel strip 1. In addition, the plurality of nozzle headers 4 are provided with at least one of the cooling gas flow rate and flow rate and the strip width of the strip 1. Control in the direction. Each of the plurality of nozzle headers 4 has a plurality of nozzles 5 provided at predetermined intervals in the length direction. In FIG. 39, reference numeral 6 denotes a conduit for supplying a cooling gas from a cooling gas storage tank (not shown) to each of the nozzle headers 4, and a plurality of branch pipes 7 branched from the conduit 6. Each is connected to each of the plurality of nozzle headers 4. In the middle of the conduit 6, a blower 8 and a cooler 9 for cooling the cooling gas passing through the conduit 6 are provided, and in the middle of each branch 7 Valve 10 is provided.

The steel strip 1 moves continuously in the direction indicated by the arrow in FIG. 38 while contacting each of the plurality of cooling rolls 2 described above. In the meantime, the surfaces of the steel strings and the jib 1 in contact with the respective surfaces of the cooling rolls 2 are cooled.

The steel strip 1 continuously cooled to a predetermined temperature by each of the plurality of cooling rolls 2 is then led to a gas cooler 3, where: Cooling gas is blown from each of the plurality of nozzle headers 4 so that the temperature distribution in the width direction of the net strip 1 after the final cooling is uniform. At least one of the flow rate and the flow rate of the cooling gas is controlled by a control valve 10 provided in the middle of each of the plurality of branch pipes 7. Fig. 40 shows the use of the cooling system according to Prior Art 2 shown in Fig. 38 to start cooling a steel strip 1 similar to that described in Prior Art 1 at about 600. This graph shows the temperature distribution in the strip width direction of steel strip 1 when cooling continuously from the temperature to the target cooling temperature of 350. In FIG. 40, the horizontal axis represents the distance from one end of steel strip 1 to the center in the sheet width direction. The vertical axis indicates the temperature in the width direction of the strip 1. In FIG. 40, the solid line indicates the temperature of the steel strip 1 at the outlet side of each of the five cooling rolls 2a to 2e, and the dotted line indicates The temperature of the steel strip 1 at the outlet of the gas cooler 3 is shown.

As shown by the solid line in FIG. 40, the temperature in the width direction of the strip 1 at the outlet side of the cooling roll 2e is approximately from one end of the steel strip 1. l Within the O OmiD, the target cooling temperature is over 350, for example, about 570 at 20rara from one end of steel strip 1. However, at the outlet side of the gas chiller 3, as shown by the dotted line in FIG. 40, the strip 1 is approximately over the entire length from one side end to the center. It shows 350 uniform temperatures.

FIG. 41 is a graph showing the number of aging measures (AI) in the strip width direction of the steel strip 1 described above. In FIG. 41, the horizontal axis indicates the distance from one end of steel strip 1 to the center in the sheet width direction, and the vertical axis indicates 鐧 strip. The aging index (AI) in the sheet width direction of 1 is shown. As is clear from FIG. 41, the portion where the aging index exceeds 4 kgf / mm ² extends from one end of the strip 1 to about 80 ram.

The above-mentioned prior art 2 has the following problems: (1) The tension of the steel strip 1 moving continuously through the plurality of cooling rolls 2 is small. . Therefore, both ends of the strip 1 in the sheet width direction are provided on the surface of each of the plurality of cooling rolls 2. Warps up. And the width and length of such a rise is large. Therefore, the temperature at both ends of the steel strip 1 in the width direction at the exit side of the plurality of cooling rolls 2 is higher than the temperature at the center.

As a result, the time and time of blowing the cooling gas onto the surface of the steel strip 1 by the gas cooler 3 to make the temperature distribution in the sheet width direction uniform after the final cooling The amount must be large. Therefore, a large-scale gas cooler 3 is required, and the equipment cost and operation cost become large.

(2) Moving continuously through the gas cooler 3. Strip 1 has low tension. As a result, run-out and meandering occur in the steel strip 1 that moves continuously through the gas cooler 3. As a result, due to the contact of the steel strip 1 with the gas cooler 3, the steel strip 1 is scratched. In order to prevent the steel strip 1 from coming into contact with the gas cooler 3. If the distance between the mesh strip 1 and the gas cooler 3 is increased, the steel strip 1 The cooling efficiency of Strip 1 decreases.

(3) The uniformity of the number of aging measures (AI) in the width direction of the net strip 1 is insufficient.

As such, the metal strip, which moves continuously along its length, is continuously cooled using at least one cooling roll and a gas cooler. During the cooling, the temperature distribution of the metal strip after the final cooling in the width direction of the metal strip is made uniform, so that the metal strip does not have ear waves, squeezing and scratches. No defects, no abnormal movement such as meandering in the next process will occur, and the equipment and operating costs of the gas cooler will be reduced, and There is a strong demand for the development of a continuous cooling system for metal strips, which can provide high quality metal strips with uniform mechanical properties in the sheet width direction. The device has not yet been proposed.

Therefore, the purpose of this invention is to use a metal strip that moves continuously along its length by using at least one cooling roll and a gas cooler. During continuous cooling, the temperature distribution in the width direction of the metal strip after the final cooling is made uniform, so that the metal strip has an ear wave, an aperture and a diaphragm. No defects such as abrasions, and abnormal movements such as running in the next process do not occur, and the equipment and operating costs of the gas cooler are reduced. Also, to provide a continuous cooling apparatus for a metal strip capable of obtaining a high-quality metal strip having uniform mechanical properties in the width direction of the sheet. It is in

Disclosure of the invention

According to one of the features of the invention, in a 'continuous cooling device for a metal strip, comprising:

At least one cooling roll, free of rotation, contacting said metal strip for continuously cooling the metal strip moving continuously in its length direction; The cooling roll, It has at least the same length as the width of the metal strip, and a cooling fluid flows through the inside of the cooling roll, so that the cooling roll is connected with a gun. Cooling, and the contact area between the surface of the cooling roll and the surface of the metal strip is controllable; and

By blowing a cooling gas onto the surface of the metal strip so that the temperature distribution in the width direction of the metal strip after the final cooling becomes uniform. A gas cooler disposed on an outlet side of the at least one cooling port for continuously cooling the metal strip; and The metal strip is arranged in the width direction of the metal strip at a predetermined interval from each of both surfaces of the lip, and the gas cooler sends the cooling gas to the metal strip. A plurality of nozzle headers independent of each other for spraying onto the surface of the nozzle, and the plurality of nozzle headers are adapted to control the flow rate and flow rate of the cooling gas. At least one of the metal strips must have the width of the metal strip To control in;

Improvements are provided that feature the following:

A first tension adjuster consisting of at least two rolls is arranged on the inlet side of the at least one cooling roll, and a first tension regulator of at least two rolls is provided. On the outlet side, a second tension regulator consisting of at least two rolls is arranged. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is an explanatory view showing a first embodiment of the device of the present invention;

FIG. 2 is a process flow diagram showing an example of a cooling system using the device of the first embodiment of the present invention;

FIG. 3 is a schematic perspective view showing an example of a gas cooler used in the device of the present invention;

Fig. 4 shows the tension of the steel strip moving through the cooling roll and the cooling roll of the における strip at the widthwise side end of the steel strip. 5 is a graph showing the relationship between the height of the rise from the surface of the gas pipe;-FIG. 5 shows the tension of the gas strip moving through the gas cooler and the gas pipe; A graph showing the relationship between trip abrasion rates;

FIG. 6 is a graph showing the relationship between each of a plurality of cooling ports when the steel strip is continuously cooled using the apparatus of the first embodiment of the present invention. A graph showing the temperature drop of the strip;

FIG. 7 shows the temperature distribution in the strip width direction of the 鐧 strip when the 鐧 strip is continuously cooled using the apparatus according to the first embodiment of the present invention. The graph shows:

FIG. 8 shows the aging index (in the width direction of the steel strip) of the steel strip when the strip was continuously cooled using the apparatus of the first embodiment of the present invention. AI));

FIG. 9 'is a schematic diagram showing an example of the device according to the first embodiment of the present invention. Schematic side view;

FIG. 10 is a graph showing the relationship between the content of hydrogen gas in the cooling gas used in the device of the present invention and the amount of heat transfer per unit time of the cooling gas. ;

FIG. 11 is an explanatory view showing a second embodiment of the device of the present invention;

FIG. 12 shows the temperature distribution in the width direction of the steel strip when the steel strip is continuously cooled using the apparatus according to the second embodiment of the present invention. The graph shows:

FIG. 13 'shows a net strip and a tab in the width direction of the steel strip when the steel strip is continuously cooled by using the apparatus according to the second embodiment of the present invention. A graph showing the aging index (AI);

FIG. 14 is an explanatory view showing a third embodiment of the device of the present invention;

FIG. 15 shows the temperature distribution in the width direction of the net strip when the net strip is continuously cooled using the apparatus of the third embodiment of the present invention. The graph shows:

FIG. 16 shows the aging index (AI) in the width direction of the net strip when the pot strip was continuously cooled using the apparatus of the third embodiment of the present invention. );

FIG. 17 is an explanatory view showing a fourth embodiment of the device of the present invention;

FIG. 18 shows the width of the steel strip when the steel strip is continuously cooled using the apparatus according to the fourth embodiment of the present invention. FIG. 19 is a graph showing the temperature distribution in the direction; FIG. 19 shows the gas stream when the steel strip was continuously cooled using the apparatus of the fourth embodiment of the present invention. A graph showing the number of aging measures (AI) in the width direction of the tip;

FIG. 20 is an explanatory view showing a fifth embodiment of the device of the present invention;

FIG. 21 is a schematic front view showing an example of a cooling roll used in the device according to the fifth embodiment of the present invention;

FIG. 22 shows the temperature distribution in the width direction of the strip when the steel strip is continuously cooled using the apparatus according to the fifth embodiment of the present invention. The graph shows:

FIG. 23 shows the aging index (in the width direction of the steel strip) of the steel strip when the strip was continuously cooled using the apparatus of the fifth embodiment of the present invention. AI).

FIG. 24 is an explanatory view showing a sixth embodiment of the device of the present invention;

FIG. 25 is a schematic side view showing an example of the device according to the sixth embodiment of the present invention;

FIG. 26 is an explanatory diagram showing the function of a thermometer used in the device according to the sixth embodiment of the present invention;

FIG. 27 shows a temperature distribution in the strip width direction of the リ strip when the して strip is continuously cooled using the apparatus according to the sixth embodiment of the present invention. Is a graph;

FIG. 28 shows an example of the apparatus according to the sixth embodiment of the present invention. A graph showing the aging index (AI) in the width direction of the steel strip when the strip is continuously cooled;

FIG. 29 is an explanatory view showing a seventh embodiment of the device of the present invention;

FIG. 30 is an explanatory view showing an eighth embodiment of the device of the present invention;

FIG. 31 shows the temperature distribution in the width direction of the steel strip when the pot strip is continuously cooled using the apparatus according to the eighth embodiment of the present invention. Is a graph;

FIG. 32 shows the steel strip in the width direction of the steel strip when the steel strip is cooled in a continuous manner using the apparatus according to the eighth embodiment of the present invention. A graph showing the aging index (AI);

FIG. 33 (A) and FIG. 33 (B) are process flow diagrams showing an example of a continuous annealing facility incorporating the apparatus according to the first embodiment of the present invention;

FIGS. 34 (A), 34 (B) and 34 (C) are schematic schematic diagrams each showing an example of a pretreatment zone for a chemical conversion treatment in a gun-annealing facility;

FIG. 35 is an explanatory view showing an example of a gun cooling device for a metal strip, for example, a steel strip, according to Prior Art 1; A graph showing the temperature distribution in the width direction of the pot strip when the steel strip is continuously cooled using the cooling device according to the present invention;

FIG. 37 shows a steel store using a cooling device according to Prior Art 1. A graph showing the aging index (AI) in the width direction of the strip when the lip is cooled;

Fig. 38 is an explanatory diagram showing an example of a continuous strip cooling device according to Prior Art 2;

Fig. 39 is a schematic perspective view showing an example of a gas cooler used in the cooling device according to Prior Art 2;

FIG. 40 is a graph showing the temperature distribution in the width direction of the steel strip when the steel strip was continuously cooled using the cooling device according to Prior Art 2. , And

Figure 41 shows the aging index (AI) in the width direction of the strip when the steel strip was continuously cooled using the cooling device according to Prior Art 2. ). BEST MODE FOR CARRYING OUT THE INVENTION

From the point of view described above, we use a continuous movement of the metal strip along its length, using at least one cooling roll and a gas cooler. When cooling, the temperature distribution in the width direction of the metal strip after the final cooling is made uniform, so that the metal strip has a shape such as ear waves and a diaphragm. No abnormal movement such as defects and scratches, and meandering in the next process will occur, and the equipment and operation costs of the gas cooler will be reduced, and It is possible to obtain a high quality metal strip with uniform mechanical properties in the width direction of the strip, and is keen to develop a continuous cooling system for metal strip. , Repeated research.

As a result, we have the following findings: at least one cooling row as described above for continuously cooling the metal strip moving along its length. A first tension regulator consisting of at least two rolls is arranged on the inlet side of the roll, and the metal strip is connected by blowing cooling gas. If a second tension regulator consisting of at least two rolls is arranged on the outlet side of the gas cooler mentioned above for gun cooling, the metal strip will have It does not cause irregular shapes such as waves and squeezes, abrasions, and abnormal movements such as running in the next process, and equipment and operating costs of the gas cooler. To obtain a high quality metal strip with uniform mechanical properties in the width direction of the board. Can Ru.

The present invention has been made based on the above findings. Hereinafter, the case of continuously cooling steel strip of the apparatus of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory view showing a first embodiment of the apparatus of the present invention. As shown in FIG. 1, the apparatus of the first embodiment is a steel strip for continuously cooling a steel strip 1 moving in a continuous manner in its length direction. Cooling gas so that the temperature distribution in the width direction of the strip 1 after the final cooling and the plurality of cooling rolls 2 that are freely rotatable and contacting the strip 1 are uniform after the final cooling. Spraying a plurality of cooling rolls 2 for continuously cooling the steel strip 1 by spraying the steel strip 1 onto the surface of the mesh strip 1. A gas cooler 3 arranged on the side of the cooling roll 2 and a first tension regulator 17 comprising at least two bridle rolls arranged on the inlet side of the plurality of cooling rolls 2; It comprises a second tension regulator 18 comprising at least two bridle rolls arranged on the outlet side of the gas cooler 3. In FIG. 1, reference numeral 19 denotes an inlet and an outlet of the gas cooler 3 for maintaining a distance between the steel strip 1 moving through the gas cooler 3 and the gas cooler 3. It is a deflector roll provided in each of the above.

The plurality of cooling rolls 2 are arranged at predetermined intervals with their axes parallel to each other. Each of the plurality of cooling rolls 2 has at least the same length as the width of the steel strip 1. The cooling liquid flows inside each of the cooling rolls 2 and cools each of the cooling rolls 2 in a continuous manner. Each of the plurality of cooling rolls 2 is driven by a drive mechanism (not shown) to control the contact area between the surface of the cooling roll 2 and the surface of the strip 1. It can be displaced toward.

The gas cooler 3 is arranged in the width direction of the steel strip 1 at a predetermined distance from each of both surfaces of the strip 1 moving continuously in the length direction. ing. The gas cooler 3 according to the device of the prior art 2 shown in FIG. 39 may be used in the present invention. That is, as shown in FIG. 39, the gas cooler 3 is provided with a plurality of mutually independent nozzle headers 4 for blowing cooling gas onto the surface of the steel strip 1. In addition, the plurality of nozzle headers 4 are used for controlling the flow rate and the flow rate of the cooling gas. At least one of them is controlled in the width direction of steel strip 1.

Each of the plurality of nozzle headers 4 has a plurality of nozzles 5 provided at predetermined intervals in the length direction. Although the nozzle 5 has a circular hole shape in the illustrated example, it may have a slit shape. In FIG. 39, reference numeral 6 denotes a conduit for supplying a cooling gas from a cooling gas storage tank (not shown) to each of the nozzle headers 4, and each of a plurality of branch pipes 7 branched from the conduit 6. Is connected to each of the plurality of nozzle headers 4. In the middle of the conduit 6, a blower 8 and a cooler 9 for cooling the gas passing through the conduit 6 are provided, and in each of the branch pipes 7, a control valve 1 is provided. 0 is provided.

FIG. 2 is a process system diagram showing an example of a cooling system using the device of the first embodiment of the present invention. As shown in Fig. 2, a thermometer 11 for continuously measuring the temperature distribution in the sheet width direction of the steel strip 1 after the final cooling is provided at the outlet of the gas cooler 3. It is provided in. The computer 12 previously stores a target temperature in the sheet width direction of the steel strip 1 after the final cooling.

The thermometer 11 measures the temperature distribution in the strip width direction of the steel strip 1 after the final cooling in a continuous manner, and sends the measurement result to the first judgment device 13 . The first judgment unit 13 compares the measurement result sent from the thermometer 11 with the target temperature in the width direction of the steel strip 1 after the final cooling sent from the computer 12. , Between the two 0 Find the difference.

The first determiner 13 determines at least one of the flow rate and the flow velocity of the cooling gas so that the value of the difference between the two determined in this way becomes zero. A signal for controlling the strip 1 in the plate width direction is sent to a control valve 10 provided in each of the plurality of branch pipes 7. In this way, each of the plurality of nozzle headers 4 of the gas cooler 3 is set so that the temperature distribution in the strip width direction of the strip 1 after the final cooling is uniform. Therefore, at least one of the flow rate and flow velocity of the cooling gas blown on the surface of the strip 1 is controlled in the width direction of the steel strip 1. Controlled o

The calculator 12 also provides a gas cooler 3 for each strip 1 thickness, heat treatment cycle (including cooling start temperature, cooling rate and target cooling temperature), and moving speed. The cooling conditions are stored.何れ When any one of the strip thickness, heat treatment cycle, and moving speed of strip 1 is changed, the change command unit 14 sends the second judgment unit based on the signal from the computer 12. Send cooling condition change signal to 15. On the other hand, the seam position detector 16 detects the seam position of the steel strip 1 whose thickness and moving speed have been changed, and sends a detection signal to the second determiner 15. The second determiner 15 sends a signal to the blower 8 and the cooler 9 based on the detection signal from the seam position detector 16, and the flow rate and flow rate of the cooling gas blown by the blower 8. At least one of them and the cooling condition of the cooling gas by the cooler 9 are controlled. to this Therefore, the cooling amount of steel strip 1 by gas cooler 3 is adjusted.

FIG. 3 is a schematic perspective view showing another example of the gas cooler used in the device of the present invention. As shown in FIG. 3, the gas cooler 3 is selectively movable in the width direction of the steel strip 1, for example, three nozzle headers 4a, 4b, 4c may be used. If the gas cooler 3 is configured as described above, it is possible to cope with a change in the width of the steel strip 1, a meandering of the steel strip 1, and the like.

As described above, in the apparatus of the first embodiment, the first tension adjuster 17 is disposed on the inlet side of the plurality of cooling doors 2, and the outlet side of the gas cooler 3. In addition, a second tension adjuster 18 is disposed. Therefore, a desired tension is applied to the steel strip 1 that moves continuously through the plurality of cooling rolls 2 and the gas coolers 3. As a result, poor contact between the surface of the mesh strip 1 and the surface of each of the plurality of cooling rolls 2 and, when passing through the gas cooler 3, the gas cooler 3 Reduces abrasion of steel strip 1 caused by contact with steel.

Fig. 4 shows the tension of steel strip 1 moving in a continuous gun while contacting each of a plurality of cooling rolls 2 and the width direction of 鐧 strip 1 4 is a graph showing the relationship between the height at which the steel strip 1 is raised from the surface of each of the cooling rolls 2 at the side end of the steel strip 1. In FIG. 4, the horizontal axis represents the tension of steel strip 1, and the vertical axis represents the side end of steel strip 1. Indicate the height of the rise from the cooling roll 2. As is clear from FIG. 4, the first tension adjuster 17 and the second tension adjuster 18 continuously contact each of the plurality of cooling rolls 2 while contacting each of them. When the tension of the moving steel strip ¹ is increased to, for example, 3 kg / mra ² or more, the cooling roll of the strip 1 at the side end of the steel strip ¹ is increased. The height of the warp 2 from each surface can be reduced to l Omra or less.

As a result, the difference between the temperature at both ends in the width direction of the steel strip 1 at the exit side of the plurality of cooling rolls 2 and the temperature at the center thereof is reduced. Therefore, in order to make the temperature distribution in the sheet width direction of the steel strip 1 after the final cooling uniform, the cooling gas is applied by the gas cooler 3 onto the surface of the strip 1. Spray time and volume are reduced. Therefore, the equipment cost and the operating cost of the gas cooler 3 are significantly reduced as compared with the device of the prior art 2. -Fig. 5 shows that the tension of the steel strip 1 moving continuously through the gas cooler 3 and the contact of the steel strip 1 with the gas cooler 3 3 is a graph showing the relationship between the occurrence rate of abrasion of steel strip 1; In FIG. 5, the abscissa indicates the tension of the strip 1, and the ordinate indicates the occurrence rate of abrasion of the steel strip 1. In FIG. 5, curve "a" indicates the rate of occurrence of abrasion when the gap between steel strip 1 and gas cooler 3 is 75 mm, and curve "b" Is abrasion when the gap between steel strip 1 and gas cooler 3 is 150πιπι Shows the incidence.

As is evident from Fig. 5, the scratching rate of steel strip 1 decreases as the tension of continuously moving pot strip 1 is increased. For example, if the tension of the strip 1 is increased to 3 Kg / ram ^{2 or more} , the mesh between the steel strip 1 and the gas cooler 3 is reduced to 75 mra, There is almost no abrasion on Trip 1. In this way, by increasing the tension of the mesh strip 1 that moves the gas cooler 3 continuously, the steel strip 1 is not scratched. In addition, the gap between the steel strip 1 and the gas cooler 3 can be reduced, so that the cooling effect of the gas cooler-3 is enhanced.

As shown in FIG. 1, the surface of the mesh strip 1 and the surfaces of the cooling rolls 2a, 2b and 2c in the first half of the plurality of cooling rolls 2 are connected to each other. The contact area between the surface of the steel strip 1 and the surface of each of the cooling rolls 2d and 2e in the latter half of the plurality of cooling rolls 2 ' It is also preferable to increase the size. The contact area between the surface of the steel strip 1 and the surface of each of the plurality of cooling rolls 2 is such that each of the plurality of cooling rolls 2 faces the steel strip 1. By controlling the displacement, it can be controlled.

FIG. 6 shows a plurality of cooling units when the steel strip 1 is cooled in a continuous manner using the apparatus of the first embodiment of the present invention shown in FIG. 5 is a graph showing the temperature drop of steel strip 1 for each of rolls 2a, 2b, 2c, 2d, and 2e. Fig. 6 As shown in Fig. 5, the contact area between the surface of steel strip 1 and the surfaces of cooling rolls 2a, 2b and 2c in the first half is increased. Accordingly, the amount of temperature drop (ΔT) of the strip 1 in each of the cooling rolls 2a, 2b and 2c in the first half becomes large. As a result, unevenness of the temperature distribution in the width direction of the strip 1 on the exit side of the cooling roll 2e is reduced.

The reason is as follows: When the strip 1 comes into contact with each of the plurality of cooling rolls 2, as described above, the strip 1 Saddle-like deformation occurs in the sheet width direction. Such saddle-shaped deformation occurs in the first cooling roll 2a in an extremely narrow portion on both end portions of the strip 1. However, as the steel strip 1 comes into contact with the cooling rolls 2b to 2e sequentially, the range of occurrence of the saddle-like deformation gradually increases. In the width direction. Therefore, both sides in the width direction of the steel strip 1 at the exit side of the final cooling roll 2e, and the ends thereof are greatly bent from the surface of the final cooling roll 2e. However, the temperature at both ends of the steel strip 1 is higher than the temperature at the center. .

Therefore, the contact area between the surface of the strip 1 and the surfaces of the cooling rolls 2a, 2b and 2c in the first half, in which the range of occurrence of saddle-like deformation is relatively small, is increased. Therefore, if the temperature drop of the steel strip 1 in the cooling rolls 2a, 2 and 2c in the first half is increased, the deformation of the steel strip 1 in the sheet width direction is increased. The steel strip 1 is restrained at both ends in the sheet width direction. The above-mentioned warping is prevented from reaching the central part. As a result, the temperature distribution in the width direction of the strip 1 at the exit side of the cooling roll 2 e is obtained. Is reduced. The contact area between the surface of the steel strip 1 and each surface of the plurality of cooling rolls 2a, 2b, 2c, 2d, and 2e is determined by comparing the contact area between the downstream cooling roll 2e and the downstream cooling roll 2e. The size of the cooling roll 2a may be gradually increased toward the cooling roll 2a.

FIG. 7 shows the use of the device of the first embodiment of the present invention shown in FIG. 1 to form steel strip 1 under the same conditions as in prior art 2. This is a graph showing the temperature distribution in the strip width direction of steel strip 1 when continuously cooled. In FIG. 7, the horizontal axis indicates the distance from one end of steel strip 1 toward the center in the sheet width direction, and the vertical axis indicates the steel strip. Shows the temperature in the sheet width direction of step 1. As shown by the solid line in FIG. 7, the temperature of the strip 1 at the outlet side of the cooling roll 2 e in the width direction of the strip 1 was measured from one end of the steel strip 1. in portions of approximately 50mm以內greater than 350 ^e C target cooling temperature, for example, the temperature of the position of one end or et 20mra of Amis preparative Clip 1 is about 480. However, at the outlet side of the gas cooler 3, as shown by the dotted line in FIG. 7, the steel strip 1 extends over the entire length from one side end to the center. It shows a uniform temperature at about 350.

Note that the dashed line in FIG. 7 indicates the above-described prior art 1, that is, the network street and tab 1 are connected only by the plurality of cooling rolls 2. This figure shows the temperature distribution in the strip width direction of steel strip 1 when continuously cooled. In addition, the two-dot chain line in FIG. 7 indicates that the strip is formed only by a plurality of cooling rolls 2 provided with a tension adjuster on each of the inlet side and the outlet side. Figure 1 shows the temperature distribution in the strip width direction of steel strip 1 when 1 was cooled. As is clear from FIG. 7, when the steel strip 1 is cooled using the apparatus of the first embodiment of the present invention, the steel strip is compared with the prior art 1. A uniform temperature distribution in the width direction of the plate 1 can be obtained.

0

FIG. 8 is a graph showing the aging index (AI) of the above-described steel strip 1 in the sheet width direction. In FIG. 8, the horizontal axis represents the distance from one end of the strip 1 to the center in the width direction of the strip 1, and the vertical axis represents the steel strip. Shows the aging index (AI) in the width direction of the plate 1 As can be seen from Fig. 8, the portion where the aging index exceeds 4 gf / ram ² extends from one end of the strip 1 to about 30 and the aging index is 4 Kgf The portion exceeding / mm ² is significantly reduced as compared with prior arts 1 and 2.

Note that the dashed line in FIG. 8 indicates that the strip 1 is continuously cooled by only the above-described prior art 1, that is, only a plurality of cooling rolls 2. The aging index of strip 1 in the width direction is shown. In addition, the two-dot chain line in FIG. 8 indicates that the steel strip 1 is formed only by a plurality of cooling rolls 2 provided with tension adjusters on each of the entrance side and the exit side. Shows the number of aging treatments in the width direction of steel strip 1 when cooled. As is clear from FIG. 8, when the steel strip 1 is cooled using the apparatus of the first embodiment of the present invention, the steel strip 1 is compared with the prior art 1. A uniform aging index in the strip width direction of Trip 1 can be obtained. Further, as apparent from comparison with the graph shown in FIG. 41, when the steel strip 1 is cooled by using the apparatus of the first embodiment of the present invention, the prior art 2 is cooled. Compared with, a uniform aging index in the strip width direction of steel strip 1 can be obtained. FIG. 9 is a schematic side view showing an example of the device according to the first embodiment of the present invention. As shown in FIG. 9, a first tension adjuster 17 composed of at least two bridle rolls is arranged on the inlet side of the plurality of cooling rolls 2. On the outlet side of the gas cooler 3, a second tension adjuster 18 composed of at least two bridle rolls is arranged. A thermometer 11 for continuously measuring the temperature distribution in the width direction of the steel strip 1 after the final cooling is provided on the outlet side of the gas cooler 3. A deflector roll 19 is provided on each of the inlet and outlet sides of the gas cooler 3.

In FIG. 9, reference numeral 20 denotes a blower driven by a motor 21 for blowing a cooling gas into the gas cooler 3 through a conduit 23, and reference numeral 22 denotes a cooling gas. It is a cooler to perform. In order to prevent the danger of gas explosion when using a mixed gas containing a large amount of hydrogen gas as a cooling gas as described below, blower 20, cooler 22, conduit 23, and gas cooling Machine 3 is located in a gas cooling chamber 24 shielded from the atmosphere . Slots 26 and 26 ′ for passing the steel strip 1 are provided at each of the inlet and outlet of the gas cooling chamber 24. A damper (not shown) is provided in the middle of the conduit 23 to control at least one of the flow rate and the flow velocity of the cooling gas in the width direction of the strip 1. ing.

As shown in FIG. 9, the steel strip 1 which is gradually cooled to a predetermined temperature in the pre-cooling zone 25 and continuously moves in its length direction is provided with the first tension adjuster 17. After that, it is led to a plurality of cooling rolls 2. The strip 1 is cooled by contact with each of the plurality of cooling holes 2. Next, the steel strip 1 is led into the gas cooling chamber 24 through the slot 26. Then, the gas is cooled in the gas cooler 3 in the gas cooling chamber 24 so that the temperature distribution in the strip width direction of the strip 1 after the final cooling is uniform. The steel strip 1 cooled by the gas cooler 3 passes through another slot 26 ′ to cover the gas cooling chamber 24, and then passes through the second tension adjuster 18. Based on the temperature distribution in the strip width direction of the steel strip 1 after the final cooling measured by the thermometer 11 guided to the next processing step, the gas cooler 3 At least one of the flow rate and the flow rate of the cooling gas blown on the surface of the trip 1 is controlled by a damper (not shown) provided in the conduit 23. .

As a cooling gas, 40 to 90 vol.% Of hydrogen gas and 10 to 60 vol.% Of nitrogen gas have large heat transfer per unit time. It is preferable to use a mixed gas. Fig. 10 shows the relationship between the content of hydrogen gas in the cooling gas consisting of a mixture gas of hydrogen gas and nitrogen gas, and the amount of heat transfer per unit time of the cooling gas. This is the graph shown. As is clear from Fig. 10, when the content of hydrogen gas in the cooling gas described above is less than 40 vol. または or more than 90 vol.¾, the heat per unit time of the cooling gas The amount of transmission decreases. The most preferred content of hydrogen gas in the cooling gas is about 70 vol.%.

The content of hydrogen gas in the cooling gas is adjusted when the steel strip 1 thickness, heat treatment cycle and moving speed are changed. If necessary, the content of hydrogen gas in the cooling gas is changed in the width direction of the mesh strip 1, thereby cooling the steel strip 1 in the width direction. The condition may be controlled. Helium gas may be used instead of hydrogen gas.

FIG. 11 is an explanatory view showing a second embodiment of the device of the present invention. As shown in FIG. 11, in the apparatus of the second embodiment, the cooling gas is supplied so that the temperature distribution in the width direction of the steel strip 1 after the final cooling is uniform. Another gas cooler 27 for continuous cooling of the steel strip 1 by spraying it onto the surface of the strip 1 is connected to the first tension adjuster 17. However, it is the same as the apparatus of the first embodiment shown in FIG. 1 except that it is arranged between a plurality of cooling rolls 2.

FIG. 12 is a cross-sectional view of the apparatus of the second embodiment of the present invention shown in FIG. 11 under the same conditions as in the first embodiment. This is a graph showing the temperature distribution in the strip width direction of steel strip 1 when strip 1 is continuously cooled. In FIG. 12, the horizontal axis indicates the distance from one end of the prison strip 1 to the center in the width direction of the strip, and the vertical axis indicates the steel strip. Shows the temperature in the width direction of the plate 1. As shown by the solid line in Fig. 12, the temperature of the steel strip 1 in the width direction at the exit side of the cooling roll 2e is within about 50 ram from one end of the steel strip 1. Above the target cooling temperature of 350. However, at the outlet side of the gas cooler 3, as shown by the dotted line in FIG. 12, the steel strip 1 extends from one side end to the center, It shows a uniform temperature at about 350.

FIG. 13 is a graph showing the aging index (AI) in the width direction of steel strip 1 described above. In FIG. 13, the horizontal axis represents the distance from one end of the strip 1 to the center in the sheet width direction, and the vertical axis represents the steel strip. Shows the aging index (AI) in the width direction of the plate 1 The Cormorant I clearly FIG. 13 or, et al., Parts aging index exceeds 4 gf / MID ² is state, and are from one side edge of the steel be sampled Clip 1 to about 30 dragon, even up to aging index 4. 8 Kg f / mm ² der one, the portion where the aging index exceeds 4 Kg f / mra ^2, compared to the prior art 1 and 2, has declined markedly.

FIG. 14 is an explanatory view showing a third embodiment of the device of the present invention. As shown in FIG. 14, the apparatus of the third embodiment supplies a cooling gas so that the temperature distribution in the strip width direction of the strip 1 after the final cooling becomes uniform. Spray on the surface of Trip 1 In this way, another gas cooler 28 for continuously cooling the steel strip 1 is provided in the middle of the plurality of cooling rolls 2, that is, in the first half. 1 except that it is arranged between the cooling rolls 2a, 2b, 2c and the cooling rolls 2d, 2e in the latter half. It is.

FIG. 15 shows a continuous strip 1 under the same conditions as in the first embodiment using the apparatus of the third embodiment of the present invention shown in FIG. This is a graph showing the temperature distribution in the strip width direction of pot strip 1 when it is cooled down. In FIG. 15, the horizontal axis represents the distance from one end of steel strip 1 to the center in the width direction of the steel strip 1, and the vertical axis represents the steel strip. Shows the temperature of Lip 1 in the sheet width direction. As shown by the solid line in FIG. 15, the temperature of the strip 1 at the outlet side of the cooling roll 2e in the width direction of the strip 1 is measured from one end of the mesh strip 1. Exceeds target cooling temperature of 350- within about 50 parts. However, at the outlet side of the gas cooler 3, as shown by the dotted line in FIG. 15, the net strip 1 has a width of approximately one end from one end to the center. It shows a uniform temperature at 350. The dashed line in FIG. 15 indicates the temperature of the strip 1 at the outlet side of another gas cooler 28.

FIG. 16 is a graph showing the aging index (AI) in the width direction of the above-mentioned net strip 1. In FIG. 16, the horizontal axis indicates the distance from one end of the steel strip 1 to the center in the width direction of the steel strip 1, and the vertical axis indicates the steel strip. In the width direction of Aging index (AI). The power sale by kana Figure 16 or RaAkira et al, portions aging index exceeds 4 gf / mm ² is state, and are from one side edge of the steel be sampled Clip 1 to about 40Mra, even up to aging index 4. At 8 gf / ram ^2, the portion where the aging index exceeds 4 Kg f / ram ² is significantly reduced as compared with prior arts 1 and 2.

FIG. 17 is an explanatory view showing a fourth embodiment of the device of the present invention. As shown in FIG. 17, the apparatus of the fourth embodiment supplies cooling gas so that the temperature distribution in the sheet width direction of the steel strip 1 after the final cooling becomes uniform. Another gas cooler 27 for continuously cooling the steel strip 1 by spraying it onto the surface of the strip 1 is connected with the first tension adjuster 17. The steel strip 1 is arranged between the plurality of cooling rolls 2 so that the temperature distribution in the width direction of the steel strip 1 after the final cooling is uniform. By blowing the cooling gas onto the surface of the strip 1, an additional gas cooler 28 for continuously cooling the strip 1 is provided. The middle part of the plurality of cooling rolls 2, that is, the point arranged between the first half cooling rolls 2a, 2b, 2c and the second half cooling rolls 2d, 2e. Except for this, it is the same as the device of the first embodiment shown in FIG.

FIG. 18 shows that the strip 1 is continuously applied under the same conditions as in the first embodiment, using the device of the fourth embodiment of the present invention shown in FIG. This is a graph showing the temperature distribution in the width direction of strip 1 when cooled. In Fig. 18, the horizontal axis is from one end of steel strip 1 to the center in the sheet width direction. The vertical axis indicates the temperature of steel strip 1 in the width direction. As shown by the solid line in FIG. 18, the temperature in the width direction of the steel strip 1 at the exit side of the cooling roll 2e is approximately one end from one end of the steel strip 1. Exceeds the target cooling temperature of 350 ^e C within 50rora. However, at the outlet side of the gas cooler 3, as shown by the dotted line in FIG. 18, the strip 1 is approximately over the entire length from one end to the center. It shows a uniform temperature at 350. The dashed line in FIG. 18 indicates the temperature of the steel strip 1 on the outlet side of the still another gas cooler 28.

FIG. 19 is a graph showing the aging index (AI) of the above-described steel strip 1 in the sheet width direction. In FIG. 19, the horizontal axis indicates the distance from one end of the steel strip 1 to the center in the sheet width direction, and the vertical axis indicates the steel strip. It shows the aging index (AI) in the width direction of step 1. As can be seen from Fig. 19, the portion where the aging index exceeds 4 Kgf / relevance ² extends from one end of the strip 1 to about 35, and the highest aging index is 4.8. The portion where the aging index exceeds 4 Kgf / mra ^2, which is Kgf / mm ² , is significantly reduced as compared with prior arts 1 and 2.

FIG. 20 is an explanatory view showing a fifth embodiment of the device of the present invention. As shown in FIG. 20, the device of the fifth embodiment is directed to a contact surface between each surface of the plurality of cooling rolls 2 and the surface of the steel strip 1. As shown in Fig. 1, except that a plurality of gas blowing nozzles 29 are provided on the cooling roll 2 side. This is the same as the device of the first embodiment described above.

The plurality of gas blowing nozzles 29 are displaced immovably or in the length direction of the cooling roll 2 at predetermined intervals in the length direction of each of the cooling rolls 2. It is provided as possible. Each of the plurality of gas blowing nozzles 29 is provided with a cooling gas so that the temperature distribution in the width direction of the steel strip 1 after the final cooling is uniform. 1Continuously cool Strip 1 by spraying it onto the surface of Strip 1. As shown in the schematic front view of FIG. 21, the surface of each of the plurality of cooling rolls 2 used in the apparatus of the fifth embodiment is provided with a blown cooling gas. It is preferable to provide a shallow groove 30 through which the water passes.

FIG. 22 shows the continuous use of the steel strip 1 under the same conditions as in the first embodiment, using the apparatus of the fifth embodiment of the invention shown in FIG. This is a graph showing the temperature distribution of steel strip 1 in the sheet width direction when it was cooled down. In FIG. 22, the horizontal axis indicates the distance from one end of the strip 1 to the center in the width direction of the strip 1, and the vertical axis indicates the steel strip. The temperature in the width direction of the top 1 is shown. As shown by the solid line in FIG. 22, the temperature in the width direction of the steel strip 1 at the exit side of the cooling roll 2e is measured from one end of the steel strip 1 Within the range of about 55rara, it exceeded the target cooling temperature of 350. However, at the outlet side of the gas cooler 3, as shown by the dotted line in FIG. 22, the steel strip 1 extends from one side end to the center. , Showing a uniform temperature at about 350. FIG. 23 is a graph showing the aging index (AI) of the above-mentioned strip 1 in the width direction of the strip. In FIG. 23, the horizontal axis indicates the distance from one end of the steel strip 1 to the center in the sheet width direction, and the vertical axis indicates the steel strip. Shows the aging index (AI) in the width direction of step 1. The power sale by kana Figure 23 or RaAkira et al, portions aging index exceeds 4 gf / ram ² is state, and are from one side edge of the steel be sampled Clip 1 to about 35Rara, maximum aging index also 5.0 Kgf / Jour ² der one, the portion where the aging index exceeds 4 Kgf / mra ^2, compared to the prior art 1 and 2, has decreased rather by remarkable.

FIG. 24 is an explanatory diagram showing a sixth embodiment of the device of the present invention. As shown in FIG. 24, the apparatus according to the sixth embodiment has a structure in which a steel sheet 1 The apparatus is the same as the apparatus of the first embodiment shown in FIG. 1, except that a plurality of gas blowing nozzles 31 are provided on the strip 1 side.

FIG. 25 is a schematic side view showing an example of the device according to the sixth embodiment of the present invention. As shown in FIG. 25, each of the plurality of gas blowing nozzles 31 is provided between the surface of each of the plurality of cooling rolls 2 and the surface of the steel strip 1. An arc-shaped nozzle header 32 provided on the side of the net strip 1 toward the contact surface, and a plurality of nozzles 33 provided at predetermined intervals on the arc-shaped nozzle header 32. It consists of.

Each of the arc-shaped nozzle headers 32 is displaceable towards the steel strip 1 by, for example, an air cylinder 34. Thus, the gap between the strip 1 and the gas blowing nozzle 31 can be adjusted. Each of the gas blowing nozzles 31 having such a structure is fixedly or longitudinally spaced from each other in the longitudinal direction of each of the cooling rolls 2. It is provided so that it can be displaced.

In the apparatus according to the sixth embodiment of the present invention, a gas cooler 3 is arranged on the outlet side of a plurality of cooling rolls 2, and a first tension adjustment is provided on an inlet side of a plurality of cooling ports 2. 1 in that a second tension adjuster 18 is disposed on the outlet side of the gas cooler 3 in the same manner as the apparatus of the first embodiment shown in FIG. It is. As shown in FIG. 25, a radiation thermometer 11a and a multiple reflection are provided as thermometers 11 at the inlet of the first tension adjuster 17 and at the outlet of the second tension adjuster 18, respectively. A thermometer lib is provided. The temperature in the strip width direction of the steel strip 1 after the final cooling is measured by the radiation thermometer 11a and the multiple reflection thermometer l ib provided on the outlet side of the second tension adjuster 18. The distribution is measured continuously. A deflector roll 19 is provided on each of the inlet and outlet sides of the gas cooler 3. In FIG. 25, reference numeral 58 denotes a sealing roll provided at each of the inlet and the outlet of the gas cooler 3, and reference numeral 59 denotes a movable partition plate.

FIG. 26 is an explanatory diagram showing functions of the radiation thermometer 11 a and the multiple reflection thermometer l ib as the thermometer 11. The radiation thermometer 11a measures the radiation temperature of the strip 1 in the width direction. The multi-reflection thermometer lib is located on the side that comes into contact with the roll. Measure the true temperature. The true temperature of steel strip 1 measured by the multiple reflection thermometer lib is sent to the computer 60. On the other hand, the radiation temperature of the steel strip 1 measured by the radiation thermometer 11a is sent to the emissivity corrector 61. The emissivity corrector 61 corrects the measured value of the radiation temperature in the width direction of the net strip 1 based on the true temperature of the strip 1 sent from the computer 60. The radiation temperature in the strip width direction of the steel strip 1 captured in this way is sent to, for example, a first judging unit 13 shown in FIG.

FIG. 27 shows the continuous use of the steel strip 1 under the same conditions as in the first embodiment, using the device of the sixth embodiment of the invention shown in FIG. This is a graph showing the temperature distribution in the width direction of strip 1 when cooled. In FIG. 27, the abscissa indicates the distance from one end of the mesh strip 1 to the center in the width direction of the strip, and the ordinate indicates the steel strip. Shows the temperature in the width direction of the plate 1. As shown by the solid line in FIG. 27, the temperature in the width direction of the strip 1 at the outlet side of the cooling roll 2e is about 380 at one end of the steel strip 1. Dedea is, by its, in the position of the steel be sampled Li Tsu one end or we about 1 0 negation of flops 1, approximately a 350 ^e C the target cooling temperature. Then, as indicated by the dotted line in FIG. 27, at the outlet side of the gas cooler 3, the temperature in the width direction of the strip 1 is equal to one side of the strip 1. At about l Omra from the end, it is slightly lower than the target cooling temperature of 350.

Fig. 28 shows the above-mentioned steel strip 1 in the width direction. This is a graph showing the effectiveness index (AI). In Fig. 28, the horizontal axis indicates the distance from one end of the strip 1 to the center in the width direction of the strip 1, and the vertical axis indicates the distance of the strip 1. It shows the aging index (AI) in the width direction of the top plate. The power sale by kana FIG. 28 or RaAkira et al, in the case of using the apparatus of the sixth embodiment to cool the steel be sampled Clip 1, the portion aging index exceeds 4 Kgf / niiB ² is rather than The aging index at both ends of the steel story,), pu 1 is extremely low.

FIG. 29 is an explanatory view showing a seventh embodiment of the device of the present invention. As shown in FIG. 29, the apparatus according to the seventh embodiment includes a third roll comprising at least-two bridle rolls between a plurality of cooling rolls 2 and a gas cooler 3. It is the same as the device of the first embodiment shown in FIG. 1 except that a tension adjuster 35 is further arranged.

When steel strip 1 was continuously cooled using the apparatus of the seventh embodiment, the temperature distribution and aging index (AI) of strip 1 in the sheet width direction were as follows: Since it is almost the same as the case of the device of the first embodiment shown in FIG. 1, detailed description is omitted.

FIG. 30 is an explanatory view showing an eighth embodiment of the device of the present invention. As shown in FIG. 30, the device of the eighth embodiment is a device for continuously cooling a steel strip 1 moving continuously in its longitudinal direction. 1 and a single cooling roll 36 that is free to rotate, so that the temperature distribution in the strip width direction of strip 1 after final cooling is uniform. By blowing gas onto the surface of steel strip 1, steel strip 1 A gas cooler 3 located on the outlet side of a single cooling roll 36 for continuous cooling and a small number of gas coolers 3 located on the inlet side of a single cooling roll 36 A first tension adjuster 17 consisting of at least two bridle rolls and at least two bridle dolls arranged on the outlet side of the gas cooler 3 And a second tension adjuster 18 consisting of:

The single cooling π-rule 36 is immobile with respect to steel strip 1. The single cooling roll 36 has at least the same length as the strip width of the steel strip 1, and the cooling liquid is supplied to the single cooling roll 36. , And continuously cools the single cooling roll 36. Control the contact area between the surface of a single cooling roll 36 and the surface of steel strip 1 on each of the inlet and outlet sides of a single cooling roll 36 A guide roll 37 is provided to guide the user. Each of the guide rolls 37 can be displaced along the outer periphery of a single cooling π-roll 36 by a drive mechanism (not shown). By displacing each of the guide rolls 37 along the outer circumference of the single cooling roll 36, the surface of the single cooling roll 36 and the steel strip The contact area with the surface of the first is controlled.

FIG. 31 shows that the apparatus of the eighth embodiment of the present invention shown in FIG. 30 was used to continuously cool the strip 1 under the same conditions as in the first embodiment. This is a graph showing the temperature distribution in the strip width direction of steel strip 1 at this time. In FIG. 31, the horizontal axis indicates the distance from one end of the steel strip 1 to the center in the width direction of the steel strip 1, and the vertical axis indicates the steel strip. Step 1 board Indicates the temperature in the width direction. As shown by the solid line in FIG. 31, the temperature of the strip 1 at the outlet side of the single cooling roll 36 in the width direction of the strip 1 is one side of the strip 1. Within about l Orani from the end, the target cooling temperature exceeded 350. However, as shown by the dotted line in Fig. 31, at the outlet side of the gas cooler 3, the steel strip 1 extends from one end to the center. It shows a uniform temperature of about 350.

FIG. 32 is a graph showing the aging index (AI) of the above-described steel strip 1 in the sheet width direction. In FIG. 32, the horizontal axis indicates the distance from one end of steel strip 1 to the center in the sheet width direction, and the vertical axis indicates the steel strip. The aging index (AI) in the sheet width direction of 1 is shown. The power sale by kana Figure 32 or RaAkira et al, portions aging index exceeds 4 Kg f / marrow ² state, and are from one end of鐧Su preparative Clip 1 to about 10, even up to the aging index 4 The part where the aging index exceeds 5 gf / ram ^2, which is 5 kgf / square ^{2, is} significantly reduced as compared with prior arts 1 and 2.

FIG. 33 (A) and FIG. 33 (B) are process flow diagrams showing an example of a continuous steel strip annealing facility incorporating the apparatus of the first embodiment of the present invention. As shown in FIGS. 33 (A) and 33 (B), between the plurality of unwinders 38 and the plurality of winders 39, the entrance looper 40, the pre-tropical zone 41, Tropical zone 42, indirect heating zone 43, average tropical zone 44, slow cooling zone 45, first cooling zone 46 including the apparatus of the first embodiment of the present invention, overaged zone (or tempering zone, hereinafter the same) 47, second cooling zone 48, and outlet looper 49 Are arranged in this order. A cutting machine 50, a welding machine 51, a cleaning device 52, and a leveler 53 are arranged in this order between the plurality of unwinders 38 and the entrance loop 40. ing.

A first tension adjuster 17, a plurality of cooling rolls 2, a gas cooler 3, and the like are provided in a first cooling zone 46 including the device of the first embodiment of the present invention. Then, the second tension adjuster 18 and the second tension adjuster 18 are arranged in this order.

Continuously between the second cooling zone 48 on the outlet side of the overaging zone 47 and the outlet looper 49 to improve the chemical conversion property and Z or lubricity of the mesh strip 1 Conversion treatment pre-treatment zone to form a small amount of nickel or nickel alloy coating and a small amount of oxide film on the surface of the annealed steel strip 1 54 Are arranged. Further, between the exit looper 49 and the plurality of winding machines 39, the temper rolling mill 55, the trimer 56 and the oiler 57 are arranged in this order.

It is rewound by any one of the plurality of unwinders 38, and both ends in the longitudinal direction are cut by the cutting machine 50. Then, the end faces are butted by the welding machine 51. The welded and continuously moving mesh strip 1 in its length direction is then passed through a cleaning device 52 where both surfaces are cleaned and then passed through a leveler 53. Guided, where the shape is dwarfed to be flat. As a result, abnormal movement due to meandering of net strip 1 in the entrance looper 40, the pre-tropical zone 41, the direct heating zone 42, the indirect heating zone 43, the isotropical zone 44, etc., and 鐧Strip 1 and furnace wall and burner Contact with one is prevented.

The steel strip 1 whose shape has been corrected by the leveler 53 passes through the entrance looper 40, passes through the pre-tropical zone 41, the direct heating zone 42, the indirect heating zone 43, and It is sequentially led to 44 and slow cooling zone 45. During this time, the 鐧 'strip 1 is preheated, directly heated, indirectly heated, soaked, and then gradually cooled according to a predetermined heat cycle. By the above-described preheating, direct heating, simple heating, and soaking, the strip 1 is uniformly heated to a predetermined temperature with less uneven burning and thermal deformation.

In particular, in the above-mentioned direct heating zone 42, since the steel strip 1 is rapidly heated, it passes through the unstable mature deformation region in a short time. Therefore, the thermal deformation of the strip 1 generated during heating is small, and the meandering of the strip 1 moving directly in the heating zone 42 is prevented.

The steel strip 1 gradually cooled to a predetermined temperature in the slow cooling zone 45 is then led to the first cooling zone 46, where the strip 1 is used for cooling a plurality of pieces. The roll 1 is continuously cooled by the cooling roll 2 and then continuously cooled by the gas cooler 3 so that the temperature distribution in the strip width direction of the strip 1 after the final cooling is uniform. Cooled down. As described above, since the steel strip 1 is straightened by the leveler 53 so that the surface shape is flat, the plurality of cooling rolls 2 are formed. However, poor contact of the strip 1 is prevented.

Steel strip cooled to the specified temperature in the first cooling zone 46 1 is then led to an overage treatment zone 47, where steel strip 1 is overaged. In the first cooling zone 46 described above, the strip 1 is cooled so that the temperature distribution in the sheet width direction of the steel strip 1 after the final cooling is uniform. Therefore, the steel strip 1 does not have any shape defects such as ear waves and iris, and therefore, moves the overage treatment zone 47 as the next process. 工程 The strip 1 has a meandering shape. Abnormal movement such as will not occur. The over-aged zone 47 is subjected to an over-aged process, and in the second cooling zone 48, the strip 1 cooled to a temperature at which it does not oxidize is then led to the pre-chemical conversion zone 54. Here, a cathodic electrolysis process forms a small amount of nickel or nickel alloy coating on the surface of the steel strip 1 and then neutral or alkaline coating. A small amount of oxide film is formed on the nickel or nickel alloy film by the immersion treatment in the immersion bath. Figs. 34 (A), 34 (B) and FIG. 34 (C) is a schematic process flow diagram showing an example of the pre-chemical conversion treatment zone 54, respectively. In the example shown in FIG. 34 (A), the pre-chemical conversion treatment zone 54 includes a cooling tank 62, an acid pickling tank 63, a water washing tank 64, a nickel / phosphorus alloy plating tank 65, and a separate tank. A washing tank 64, a scrubber 66, a neutralization tank 67, another scrambler 66, a hot water tank 68, and a cold water tank 69. The steel strip 1 passes through a cooling tank 62, an acid pickling tank 63 and a water washing tank 64 and is led to a nickel-phosphorus alloy plating tank 65, where it is subjected to cathodic electrolytic treatment. Traces of steel on the surface of steel strip 1 Nickel-phosphorus alloy plating film is formed. In this way, the steel strip 1 having the nickel-phosphorus alloy plating film formed on its surface is then separated into another washing tank 64, a scrubber 66, and a After passing through a sump tank 67 and another scrubber 66, it is led to a hot water tank 68 and a cold water tank 69, where a trace oxide film is formed on the nickel-phosphorus alloy plating film.

The example shown in FIG. 34 (B) is the same as that shown in FIG. 34 (A) except that a nickel plating tank 70 is provided in place of the nickel / metal alloy plating tank 65 described above. This is the same as the example shown in). The example shown in FIG. 34 (C) is similar to that of FIG. 34 (B) except that a water spray tank 71 is provided instead of the above-described scrubber 66 and neutralization tank 67. This is the same as the example shown.

Direct heat reduction heating in the direct heating zone 42, indirect heating zone 43 and isotropy heating in a weak reducing atmosphere, and non-oxidative cooling in the first cooling zone 46 As a result, the surface of the continuously annealed steel strip 1 is beautiful. However, the chemical conversion property and / or lubricity of Strip 1 is not always good. Therefore, as described above, in the chemical conversion treatment pretreatment zone 54, a small amount of nickel or nickel alloy film and a minute amount of oxide film are formed on the surface of the steel strip 1. Thereby, the above-mentioned problem is solved, and the chemical conversion treatment property and the Z or lubricity of the strip 1 are improved.

Steel subjected to the pretreatment described above in the chemical conversion pretreatment zone 54 Next, the strip 1 is guided to the temper rolling mill 55 through the outlet looper 49, where the steel strip 1 is temper-rolled. Next, the steel strip 1 is trimmed by trimmers 56, its ears are trimmed, and after the oil-proof oil is applied by the oiler 57, a plurality of windings are formed. It is wound into a coil by any of the take-up machines 39.

Since the temperature distribution in the strip width direction of the steel strip 1 after the final cooling in the above-described process is uniform, the aging index in the strip width direction is also substantially uniform. Therefore, it is possible to produce high-quality steel strips with uniform mechanical properties.

In the above, the apparatus of the present invention has been described mainly regarding the cooling applied when continuous annealing of a steel strip made of a normal aluminum mesh is performed. However, the apparatus of the present invention provides, for example, cooling for quenching and tempering a steel strip made of high-strength steel in a continuous gun, carbon and nitrogen contained in the steel. A net strip consisting of aluminum containing a trace amount of at least one of titanium, niobium, zirconium, nonadium, and boron to fix Cooling during annealing, cooling applied to the strip after continuous annealing on the inlet side of the melting plating tank in the continuous melting plating equipment, and exit of the melting plating tank On the side, it can also be used for cooling, etc., which is applied to the steel strip after the molten plating.

As described in detail above, according to the present invention, the metal strip moving continuously in the length direction is provided with at least one cooling strip. In the continuous cooling using a π-roll and gas cooler, the temperature distribution in the width direction of the metal strip after final cooling is made uniform. Therefore, the metal strip is free from irregular shapes such as ear waves and iris, scratches, and abnormal movement such as meandering in the next process. Equipment and operation costs are low, and a metal strip that can provide a high-quality metal strip with uniform mechanical properties in the width direction of the board. Can provide a continuous cooling system for the pump, and thus have an industrially useful effect.

-3 ο "

Claims

The scope of the claims

1. A metal strip continuous cooling device, comprising: a metal strip for continuously cooling a metal strip moving in a longitudinal direction of the metal strip; At least one cooling roll that is free to rotate and that contacts the strip, the cooling roll having at least the same length as the width of the metal strip. The cooling liquid flows through the inside of the cooling roll to continuously cool the cooling roll, and the surface of the cooling roll and the metal plate are cooled. The contact area with the surface of the trip is controllable; and

By blowing a cooling gas onto the surface of the metal strip so that the temperature distribution in the width direction of the metal strip after the final cooling becomes uniform. A gas cooler disposed on an outlet side of the at least one cooling roll for continuously cooling the metal strip, wherein the gas cooler comprises: The metal strip is disposed in the width direction of the metal strip at a predetermined distance from each of both surfaces of the metal strip, and the gas cooler sends the cooling gas to the metal strip. A plurality of mutually independent nozzle headers for spraying on the surface of the nozzle, and the plurality of nozzle headers are provided for the cooling gas. At least one of the flow rate and flow rate shall be in the width direction of the metal strip. Control ;

Improvements featuring:

A first tension adjuster consisting of at least two rolls is arranged on an inlet side of the at least one cooling roll, and a first tension adjuster composed of at least two rolls is provided. On the outlet side, a second tension adjuster consisting of at least two portals is arranged.

2. Apparatus that is claimed in claim 1 and that has the following features: The thermometer for continuously measuring the temperature distribution in the sheet width direction of the metal strip after the final cooling is as described above. It is provided on the outlet side of the gas cooler.Based on the temperature distribution measured by the thermometer, the plurality of nozzle headers of the gas cooler can At least one of the flow rate and the flow rate of the cooling gas blown onto the surface of the metal strip is controlled in the width direction of the metal strip.

3. Apparatus framed in claim 1 which features: the cooling gas is hydrogen gas in an amount in the range of 40 to 90 vol.% And in the range of 10 to 60 vol.%. The amount of nitrogen gas contained in the gas.

4. Apparatus in claim 1 characterized by the following: the at least one cooling port has an axis that is mutually -5 units-/ 02645 Consists of a plurality of cooling rolls parallel to PCT / JP91 / 01009, each of the plurality of cooling rolls being a metal stud. Moveable toward the metal strip to control the contact area between the metal strip and the metal strip.

5. Apparatus in claim 4 characterized by the following features: of the plurality of cooling rolls, the surface of each of the first half of the cooling rolls and the metal strip. The contact area with the surface is larger than the contact area between the surface of each of the cooling rolls in the second half and the surface of the metal strip.

6. Apparatus combed to claim 4 or 5, characterized by:

A cooling gas is blown onto the surface of the metal strip so that the temperature distribution in the width direction of the metal strip after the final cooling becomes uniform. Another gas cooler for continuously cooling the metal strip is disposed between the first tension adjuster and the plurality of cooling rolls.

7. Apparatus claimed in claim 4 or 5, characterized by:

Cooling gas is supplied to the metal strip so that the temperature distribution in the width direction of the metal strip after the final cooling is uniform. Another gas cooler for successively cooling the metal strip by spraying on the surface of the strip is provided in the middle of the plurality of cooling rolls. Located in the department.

8. Apparatus claimed in claim 4 or 5, characterized by:

By blowing a cooling gas onto the surface of the metal strip so that the temperature distribution in the width direction of the metal strip after the final cooling becomes uniform. Another gas cooler for continuously cooling the metal strip is disposed between the first tension adjuster and the plurality of cooling rolls. Then, a cooling gas is blown onto the surface of the metal strip so that the temperature distribution in the width direction of the metal strip after the final cooling is uniform. Therefore, still another gas cooler for continuously cooling the metal strip is arranged at an intermediate portion between the plurality of cooling rolls.

9. Apparatus claimed in claim 4 or 5, characterized by:

A plurality of gas blowing nozzles are provided on the cooling roll side toward a contact surface between a surface of each of the plurality of cooling rolls and a surface of the metal strip. A nozzle is provided, and each of the plurality of gas blowing nozzles is Cooling gas is blown onto the surface of the metal strip so that the temperature distribution in the width direction of the metal strip after the final cooling is uniform. Thus, the metal strip is continuously cooled. 0. Equipment claimed in claim 4 or 5, characterized by:

A plurality of gas blows toward the metal strip side toward a contact surface between a surface of each of the plurality of cooling rolls and a surface of the metal strip. Nozzles are provided, and each of the plurality of gas blowing nozzles has a uniform temperature distribution in the width direction of the metal strip after the final cooling. Thus, the metal strip is continuously cooled by spraying the cooling gas on the surface of the metal strip. 1. A device claimed in claim 4 or 5, characterized by:

A third tension adjuster including at least two rolls is disposed between the plurality of cooling rolls and the gas cooler. 2. Combine to claim 1 characterized by:

The at least one cooling roll has a single cooling port The single cooling roll is immovable with respect to the metal strip, and is located at the entrance of the single cooling hole. And a guide roll for controlling the contact area between the surface of the single cooling roll and the surface of the metal strip on each of the outlet side and the outlet side. In addition, each of the guide rolls is movable along the outer circumference of the single cooling roll, and at least on the entrance side of the single cooling roll, Both--a first tension regulator consisting of two rolls is arranged, and at the outlet side of said gas cooler at least two rolls; A second tension adjuster is arranged.