KR20140005689A - Accelerated cooling apparatus for thermo-mechanical control process - Google Patents

Abstract

The present invention relates to an accelerated cooling apparatus of a thermo mechanical control process for accelerated cooling a steel plate transferred after the steel plate is rolled comprising: a first cooling spray part, which is located in an upper part of the steel plate in a state of being separated from the steel plate, for spraying a cooling water to an upper part of the steel plate; and a second cooling spray part, which is located in a lower part of the steel plate and the first cooling spray part in a state of being separated from the steel plate, for spraying a cooling water to a lower part of the steel plate. A cooling water is sprayed from more than one between the first cooling spray part and the second cooling spray part. A smaller flux of the cooling water is sprayed to a side part of the steel plate than a center part of the steel plate toward the width direction of the steel plate. Since a different flux is sprayed to a leading end, a rear end, and a center part toward the length direction of the steel plate, a different up and down flux rate is applied. A physical property and a shape of a cooled steel plate are maintained since the accelerated cooling apparatus of a thermo mechanical control process uniformly cools a steel plate transferred after rolling along the length direction and the width direction.

Description

ACCELERATED COOLING APPARATUS FOR THERMO-MECHANICAL CONTROL PROCESS}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an accelerated cooling apparatus of a heat processing control process, and more particularly, to an accelerated cooling apparatus of a heat processing control process for improving physical properties of a steel sheet and maintaining the shape of the steel sheet.

The thermo-mechanical control process (TMCP) controls the heating temperature, rolling temperature, and rolling amount of the steel sheet in the general rolling process to refine the crystal structure of the steel sheet to improve mechanical properties, and to accelerate the subsequent cooling process. The process is further applied. As a result, the steel sheet has physical properties to be finally obtained.

TMCP steel, a steel sheet to which a heat treatment control process is applied, has improved tensile strength and workability. This TMCP steel is used as a deep plate for shipbuilding and building structures. For example, when a ship is built using TMCP steel, the weight of the ship is reduced and fuel economy is reduced, there is an advantage that the operating cost is reduced. In addition, since the yield ratio of TMCP steel can be lowered by accelerated cooling, in the case of a building structure using TMCP steel, even if an earthquake occurs, deformation of the structure occurs but does not reach breakage.

On the other hand, in the heat treatment control process, the accelerated cooling process is generally made by the injection of cooling water toward the steel sheet. At this time, the spray pattern of cooling water is uniform over the whole steel plate with the same up-down flow ratio from the front-end | tip of a steel plate to a rear-end part. For this reason, the steel sheet has a temperature deviation along the longitudinal direction and the width direction through an accelerated cooling process. Therefore, since the steel sheet is not uniformly cooled as a whole in the process of being made of TMCP steel, it is difficult to have uniform physical properties and shapes.

The present invention is to provide an accelerated cooling apparatus of a heat processing control process that can cool the steel sheet to be transported after rolling to have a uniform temperature distribution.

In addition, the present invention is to provide an accelerated cooling apparatus of the heat processing control process to maintain the uniform physical properties and shape of the cooled steel sheet.

The present invention is an accelerated cooling apparatus of a heat processing control process for accelerating cooling a steel sheet conveyed after being rolled, the first cooling device being positioned above the steel sheet in a state spaced apart from the steel sheet, and spraying cooling water on the upper surface of the steel sheet. Cooling jet; And a second cooling spraying unit positioned below the first cooling spraying unit and the steel sheet in a state spaced apart from the steel sheet, and spraying cooling water onto a lower surface of the steel sheet, wherein the first cooling spraying unit and the second cooling spraying unit are provided. Cooling water injected from at least one of the cooling jet parts is injected at a flow rate less than the center part of the steel sheet in the flow direction of the steel sheet at a lower flow rate, and the front end, the rear end and the middle part with respect to the longitudinal direction of the steel sheet. Disclosed is an accelerated cooling apparatus of a heat processing control process characterized by spraying at different flow rates at different flow rates.

The accelerated cooling device may further include masking portions positioned to correspond to side portions of the steel sheet between at least one of the steel sheet and the first cooling spray unit, and between the steel sheet and the second cooling spray unit. An accelerated cooling apparatus of a heat processing control process is disclosed.

In addition, the width of the side portion of the steel sheet discloses an accelerated cooling apparatus of the heat processing control process, characterized in that calculated by the following equation.

[Mathematical Expression]

Width of side part of steel sheet = {(-0.92 × thickness of steel sheet) + (0.036 × width of steel sheet) + (0.15 × spray flow coefficient ÷ 1000)} × 1000

In addition, any one of the first cooling injection unit and the second cooling injection unit injects the cooling water at a flow rate according to the length, thickness and width of the conveyed steel sheet, the first cooling injection unit and the second cooling powder. The other one of the four parts is sprayed with the cooling water in the middle portion at a flow rate corresponding to the up and down flow rate ratio according to the length, thickness and width of the conveyed steel sheet, and based on the flow rate injected to the front end portion and the rear end portion in the middle portion Disclosed is an accelerated cooling apparatus of a thermal processing control process, characterized by spraying cooling water at an increased or decreased flow rate.

In addition, the vertical flow rate ratio applied to the steel sheet by the first cooling injection unit and the second cooling injection unit is 0.7 to 1.2 in the middle portion, characterized in that the front end and the rear end is 0.6 to 1.4, respectively. An accelerated cooling device of a heat processing control process is disclosed.

In addition, the accelerated cooling device is located adjacent to the first cooling sprayed portion and the accelerated cooled steel plate and adjacent to the second cooling sprayed portion and the accelerated cooled steel sheet to measure the surface temperature of the accelerated cooled steel sheet. And measuring unit for calculating the temperature difference in the vertical direction and the width direction of the steel sheet; And connecting the measuring unit with the first cooling spray unit, the measuring unit, and the second cooling spray unit, and the temperature is based on the temperature difference along the up and down temperature difference and the width direction calculated by the measuring unit. And a control unit for adjusting a flow rate of the cooling water sprayed from at least one of the first cooling spray unit and the second cooling spray unit with respect to the steel sheet having the same length, thickness, and width as the measured steel sheet. The accelerated cooling device of a process control process is disclosed.

The control unit may further include at least one of the first cooling spray unit and the second cooling spray unit to maintain a predetermined range between the vertical temperature difference and the temperature difference along the width direction of the accelerated cooled steel sheet calculated by the measuring unit. Disclosed is an accelerated cooling apparatus of a thermal processing control process, characterized by adjusting a flow rate of injected cooling water.

The accelerated cooling apparatus of the heat processing control process according to the present invention has the following effects.

(1) The accelerated cooling apparatus of the heat processing control process according to the present invention includes a first and a second cooling spraying unit and a masking unit to cool the steel sheet conveyed after being rolled. In this case, the first and second cooling jets receive the steel sheet information (for example, overall length, width, thickness, temperature, and the like), and divide the steel sheet into a front end portion, a rear end portion, and an intermediate portion along the conveying direction, respectively. Cooling water is injected at the flow rate ratio up and down. In addition, the masking portion is positioned so as to correspond to the side portion of the steel sheet to be conveyed in consideration of the size of the steel sheet, in particular the thickness and width, to prevent the temperature drop of the side portion of the steel sheet. Therefore, the accelerated cooling apparatus of the thermal processing control process according to the present invention has the effect of cooling the steel sheet to have a uniform temperature distribution along the longitudinal direction and the width direction.

(2) The accelerated cooling apparatus of the heat processing control process according to the present invention produces a cooled steel plate with a uniform temperature distribution. In general, the steel sheet is cooled to have a non-uniform temperature distribution, so that the quality may be degraded or the shape may be deformed. Therefore, the accelerated cooling apparatus of the heat processing control process according to the present invention provides the uniform temperature distribution of the cooled steel sheet, and has the effect of preventing the deterioration of the quality of the steel sheet and deformation of the shape.

1 is a side view illustrating an accelerated cooling apparatus of a heat processing control process according to a preferred embodiment of the present invention.
FIG. 2 is a cross-sectional view showing an accelerated cooling device of the thermal processing control process shown in FIG. 1.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

FIG. 1 is a side view showing an accelerated cooling apparatus 100 of a heat processing control process according to a preferred embodiment of the present invention, and FIG. 2 shows an accelerated cooling apparatus 100 of a heat processing control process shown in FIG. It is a cross section.

As shown in Figure 1 and 2, the accelerated cooling apparatus 100 of the heat processing control process according to a preferred embodiment of the present invention, the first cooling injection unit 101, the second cooling injection unit 102 and masking It is used to accelerate the cooling of the steel sheet S, which is conveyed in the conveying direction A by the conveying rolls 10 after rolling, to be finally made of TMCP steel.

The 1st cooling spray part 101 is located in the state spaced apart from the upper surface of the steel plate S with respect to the conveyance direction A, and is located above the steel plate S. FIG. The first cooling spray unit 101 cools the steel sheet S by spraying cooling water on the upper surface of the steel sheet S.

The 2nd cooling spray part 102 is located in the state spaced apart from the lower surface of the steel plate S with respect to the conveyance direction A, and is located under the 1st cooling spray part 101 and the steel plate S. FIG. The second cooling spray unit 102 cools the steel sheet S by spraying cooling water on the lower surface of the steel sheet S.

Further, the steel sheet S is divided into a front end S1, a rear end S2, and an intermediate part S3, as shown in FIG. 1, and the middle part S3 is a front end S1 and a rear end S2. ). The first cooling jetting unit 101 and the second cooling jetting unit 102 in combination inject the cooling water to the front end portion S1, the rear end portion S2 and the middle portion S3 at different up and down flow ratios, respectively. Here, the up-and-down flow rate ratio is a ratio of the flow volume of the cooling water sprayed on the upper surface of the steel plate S with respect to the flow volume of the cooling water sprayed on the lower surface of the steel plate S.

Here, the length L, the thickness t, the width W, and the like of the steel sheet S are considered when the steel sheet S is divided into the front end portion S1, the rear end portion S2, and the middle portion S3. . Preferably, when the length L of the steel sheet S is 20 m or less, the length of the middle portion S3 is 10 m to 19 m, and the length of each of the front end portion S1 and the rear end S2 is 0.5 m to 5 m. to be. Further, when the length of the steel sheet S exceeds 20 m and is 40 m or less, the length of the intermediate portion S3 is 10 m to 39 m, and the length of each of the front end portion S1 and the rear end S2 is 0.5 m to 15 m. . When the length of the steel sheet S exceeds 40 m, the length of the intermediate portion S3 is 25 m to 64 m, and the length of each of the front end portion S1 and the rear end portion S2 is 0.5 m to 20 m. In addition, the thickness t of the steel sheet S is preferably 100 mm or less while exceeding 0 mm, and the width W of the steel sheet S is preferably 1500 mm to 4500 mm.

As the steel sheet S is partitioned into the leading end portion S1, the rear end portion S2, and the intermediate portion S3 according to the above range, the steel sheet S has different vertical flow rate ratios applied along the longitudinal direction, Thus cooled to have a uniform temperature distribution.

In addition, the cooling injection by the 1st cooling injection part 101 and the 2nd cooling injection part 102 is preferably according to the length L, the thickness t, and the width W of the steel plate S to be cooled. The first cooling jetting unit 101 sprays the cooling water at a uniform flow rate with respect to the front end S1, the rear end S2 and the middle portion S3, and is different from the second cooling jetting unit 102. This can be done by injecting cooling water at a flow rate. For this reason, a different vertical flow rate ratio may be applied to the steel sheet S along the longitudinal direction. The present invention is not limited thereto, and the cooling spraying by the first cooling spraying unit 101 and the second cooling spraying unit 102 may be performed in reverse with respect to the above. Different flow rates of coolant injection may be achieved by both the first cooling jet 101 and the second cooling jet 102.

In addition, an up-down flow rate ratio is set according to the flow volume of the cooling water sprayed by the 1st cooling injection part 101 and the 2nd cooling injection part 102 as mentioned above. Here, the up-down flow rate ratio with respect to the front-end | tip part S1, the rear-end | tip part S2, and the intermediate part S3 is set by the length L of the steel plate S, width W, and thickness t. The vertical flow rate ratio with respect to the middle part S3 is set by the length L, width W, and thickness t of the steel plate S, and exists in the range of 0.7-1.2. On the other hand, the up and down flow rate ratio for each of the front end portion (S1) and the rear end (S2) can be adjusted by increasing or decreasing the flow rate of the cooling water based on the up and down flow rate ratio for the middle portion (S3), the middle portion (S3) It exists in the range of 0.6-1.4, different from the up-down flow ratio with respect to.

When the vertical flow rate ratio by the first cooling spray unit 101 and the second cooling spray unit 102 is in the above range, the steel sheet S may be cooled to have physical properties to be obtained.

For example, when a steel plate S having a thickness t of 23 mm, a width W of 4200 mm, and an overall length L of 28 m is applied, the steel plates S each have a tip portion having a length of 8 m. It is divided into S1, the rear end S2, and the intermediate portion S3 having a length of 12 m. At this time, the cooling water is sprayed on the steel sheet S at the top and bottom flow ratios of 0.94, 0.92, and 0.86 with respect to the front end S1, the rear end S2, and the middle S3, respectively.

The masking portions 103 are positioned between the steel sheet S and the first cooling spraying portion 101 and between the steel sheet S and the second cooling spraying portion 102 along the feed direction A of the steel sheet S, respectively. do. At this time, the masking portions 103 are positioned to correspond to the side portions SS of the steel sheet S. At this time, the side part SS of the steel plate S is located along the width direction of the steel plate S (that is, the direction orthogonal to the conveyance direction A of the steel plate S) from the side end surface of the steel plate S ( It is a part facing the center part SC of S). The masking portions 103 prevent the coolant injected from the first and second cooling injection units 101 and 102 from reaching the side portion SS of the steel sheet S directly.

In addition, the width Wm of the side part SS is obtained by the following equation.

[Mathematical Expression]

Width (Wm) of side portion (SS) = ((-0.92 × thickness (t) of steel sheet (S)) + (0.036 × width (W) of steel sheet (S)) + (0.15 × injection flow rate coefficient ÷ 1000) } × 1000

Here, the unit of the width Wm of the side part SS, the unit of the thickness t of the steel plate S, and the unit of the width W of the steel plate S are mm. Further, the injection flow rate coefficient is a constant according to the flow rate of the cooling water by the first cooling injection unit 101 and the second cooling injection unit 102.

Based on the above equation, the width Wm of the side portion SS has a value as follows. For example, when the thickness t of the steel sheet S is 20 mm and the width W of the steel sheet S is 3000 mm, the width Wm of the side portion SS is 200 mm.

In addition, as the masking part 103 has a size corresponding to the width Wm of the side part SS as described above, a center part (3) is provided in each of the side parts SS with respect to the width direction of the steel sheet S. As shown in FIG. About 20% less coolant flow is injected compared to SC). For this reason, the masking parts 103 compensate for the cooling of the side part SS along the width direction of the steel plate S, so that the steel plate S has a uniform temperature distribution along the width direction.

On the other hand, the masking portion 103 according to the present embodiment is shown to be located between both the steel sheet (S) and the first cooling spraying unit 101 and between the steel sheet (S) and the second cooling spraying unit (102) However, the present invention is not limited thereto, and may be positioned only between any one of the steel sheet S and the first cooling spray unit 101 and between the steel sheet S and the second cooling spray unit 102. In addition, the masking portions 103 according to the present embodiment are not used, and at least one of the first cooling spraying portion 101 and the second cooling spraying portion 102 is provided with respect to the side portion SS of the steel sheet S. Cooling water may be injected at a reduced flow rate (for example, 20%) compared to the center portion SC, thereby compensating cooling of the side portion SS along the width direction of the steel sheet S. Referring to FIG.

The accelerated cooling apparatus 100 of the thermal processing control process according to the present invention cools the steel sheet S to have a uniform temperature distribution along the longitudinal direction and the width direction as described above. To this end, before the accelerated cooling apparatus 100 accelerates the cooling of the steel sheet (S), information about the steel sheet (S) (for example, the total length (L), width (W), thickness (t), temperature, etc.) ), The steel plate (S) according to this is divided into a front end (S1), a rear end (S2) and the middle (S3) and set the flow rate ratio for each, and the width (Wm) of the side (SS) Set.

Further, as described above, since the steel sheet S is cooled to have a uniform temperature distribution along the longitudinal direction and the width direction, the physical properties of the steel sheet S are lowered due to the nonuniform temperature distribution in the past, and the steel sheet S is The deformation can be prevented. In addition, even if the external environment changes with the season, the cooling of the steel sheet (S) is appropriately made accordingly.

In addition, the accelerated cooling apparatus 100 of the thermal processing control process according to the present invention may further include a measuring unit 104 and the control unit 105.

The measuring unit 104 is positioned adjacent to the first cooling spray unit 101 and the accelerated cooled steel sheet S, respectively, and is located adjacent to the second cooling spray unit 102 and the accelerated cooled steel sheet S, The surface temperature of the accelerated cooled steel plate S is measured. At this time, the measurement part 104 calculates the temperature difference along the up-down temperature difference of the steel plate S, and the width direction. Here, the vertical temperature difference is the temperature difference between the upper surface and the lower surface of the steel sheet S in the same partitioned region of the steel sheet S, and the temperature difference along the width direction is the steel sheet S in the same partitioned region of the steel sheet S. Is the temperature difference between the highest and lowest temperature points along the width direction.

On the other hand, the measurement unit 104 may be located adjacent to the steel sheet S before the accelerated cooling to measure the surface temperature of the steel sheet S before cooling. At this time, the measured surface temperature of the steel sheet S is compared with the surface temperature of the accelerated-cooled steel sheet S to cool the steel sheet S by the first cooling spray unit 101 and the second cooling spray unit 102. It can be used to check the status.

The control unit 105 connects the measurement unit 104 and the first cooling injection unit 101, and the measurement unit 104 and the second cooling injection unit 102, respectively. At this time, the control unit 105 measures the same length, thickness, and width as the steel plate S, the temperature of which is measured based on the temperature difference along the up and down temperature difference and the width direction of the steel plate S calculated by the measuring units 104. The flow rate of the cooling water injected from at least one of the 1st cooling injection part 101 and the 2nd cooling injection part 102 with respect to the steel plate which it has is adjusted. That is, the up-down flow rate ratio with respect to the steel plate S is adjusted. At this time, it is preferable that the control unit 105 adjusts the flow rate of the cooling water when the temperature difference along the vertical direction or the width direction of the steel sheet S is out of a predetermined range. That is, the control unit 105 can be used to maintain the temperature difference along the vertical direction or the width direction of the steel sheet (S) does not lower the physical properties of the steel sheet (S).

For example, when the up and down temperature difference of the steel sheet S, the temperature of which is accelerated and cooled, is 10 ° C. or more, the controller 105 may correct the temperature difference. Adjust the flow rate of the cooling water injected from at least one of the). At this time, the flow rate of the cooling water may be increased for a point where the temperature of the steel sheet S is relatively high, and the flow rate of the cooling water may be reduced for a point where the temperature of the steel sheet S is relatively low. For this reason, the vertical flow rate ratio may be adjusted so that the steel sheet S is cooled to have a more uniform temperature distribution.

On the other hand, the control unit 105 may be operated by an operator. For this reason, the flow rate of the cooling water by at least one of the 1st cooling injection part 101 and the 2nd cooling injection part 102 may be adjusted by an operator based on said temperature difference.

While the present invention has been described in connection with certain exemplary embodiments, it will be understood by those skilled in the art that various changes may be made without departing from the scope of the present invention. In addition, the description in parentheses in the description of the claims is intended to prevent obscuration of the description, and the scope of the claims of the claims should be construed to include all the items in parentheses.

100: accelerated cooling unit of the thermal processing control process
101: first cooling jet
102: second cooling jet
103: masking part
104: measuring unit
105:

Claims (7)

In the accelerated cooling apparatus of the heat processing control step of accelerated cooling the steel sheet conveyed after rolling,
A first cooling spray unit positioned above the steel sheet in a state spaced apart from the steel sheet to spray cooling water onto the upper surface of the steel sheet; And
Includes the first cooling spraying unit and the second cooling spraying unit which is located below the steel sheet in a state spaced apart from the steel sheet, spraying the cooling water on the lower surface of the steel sheet,
Cooling water injected from at least one of the first cooling spray unit and the second cooling spray unit is injected to the side portions of the steel sheet at a lower flow rate than the center portion of the steel sheet with respect to the width direction of the steel sheet, and the length of the steel sheet. An accelerated cooling apparatus of a heat processing control process, characterized by spraying at different flow rates at a front end, a rear end, and an intermediate part with respect to a direction to apply different up and down flow rates.
The method of claim 1, wherein the accelerated cooling device,
And a masking portion positioned to correspond to the side portion of the steel sheet between at least one of the steel sheet and the first cooling spraying portion, and between the steel sheet and the second cooling spraying portion. Accelerated cooling unit.
3. The method according to claim 1 or 2,
Width of the side portion of the steel sheet is an acceleration cooling device of the heat processing control process, characterized in that calculated by the following equation.
[Mathematical Expression]
Width of side part of steel sheet = {(-0.92 × thickness of steel sheet) + (0.036 × width of steel sheet) + (0.15 × spray flow coefficient ÷ 1000)} × 1000
The method of claim 1,
Any one of the first cooling injection unit and the second cooling injection unit injects the cooling water at a flow rate according to the length, thickness and width of the conveyed steel sheet,
The other one of the first cooling injection unit and the second cooling injection unit injects the cooling water to the middle portion at a flow rate corresponding to the vertical flow rate ratio according to the length, thickness and width of the conveyed steel sheet, the front end portion and the after An end portion of the accelerated cooling apparatus of the heat processing control process, characterized in that for spraying the cooling water at an increased or decreased flow rate based on the flow rate injected into the intermediate portion.
The method of claim 1,
The upper and lower flow rate ratios applied to the steel sheet by the first cooling spray unit and the second cooling spray unit are 0.7 to 1.2 in the intermediate portion, and 0.6 to 1.4 in the front and rear ends, respectively. Accelerated cooling unit of control process.
The method of claim 1 or 4, wherein the accelerated cooling device,
A surface temperature of the accelerated cooled steel plate is measured by being located adjacent to the first cooling spray unit and the accelerated cooled steel plate and adjacent to the second cooling spray unit and the accelerated cooled steel plate, A measuring unit calculating a temperature difference along the width direction; And
The temperature is measured on the basis of the temperature difference along the up and down temperature difference and the width direction of the steel sheet calculated by the measuring unit by connecting the measuring unit and the first cooling spray unit and the measuring unit and the second cooling spray unit. And a control unit for adjusting a flow rate of the cooling water sprayed from at least one of the first cooling spray unit and the second cooling spray unit with respect to the steel sheet having the same length, thickness, and width as the steel sheet. Accelerated cooling unit of control process.
The method according to claim 6,
The control unit is sprayed from at least one of the first cooling injection unit and the second cooling injection unit to maintain a predetermined range of the temperature difference in the vertical direction and the width direction of the accelerated-cooled steel sheet calculated by the measuring unit Accelerated cooling device of the thermal processing control process, characterized in that for adjusting the flow rate of the cooling water.

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