• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    method for cooling a hot rolled steel strip. The invention relates to a method for cooling a hot rolled steel strip after a finish roll in which a conveyor speed varies, the method including: adjusting a conveyor speed change schedule based on a temperature of a steel strip before the finish roll and a finish roll condition; performing a first cooling in which the hot rolled steel strip is cooled under a film boiling state in a first cooling section; performing a first cooling in which hot-rolled steel strip is cooled under a film boiling state in a first cooling section; perform a second cooling in which the hot rolled steel strip is cooled to a water quantity density not less than 2m3/min/m3 in a second cooling section; and winding the hot-rolled steel strip wherein a cool-down condition is controlled on the first cool-down so as to satisfy 0.8 (less equal) (t2a' - t2a)/(delta)tx (less equal) 1.2.
    公开号:BR112012004729B1
    申请号:R112012004729-9
    申请日:2010-12-16
    公开日:2021-07-20
    发明作者:Isao Yoshii；Noriyuki Hishinuma；Yoshiyuki Furukawa；Satoru Ishihara
    申请人:Nippon Steel Corporation；
    IPC主号:
    专利说明:

    FIELD OF TECHNIQUE
    [0001] The present invention relates to a method for cooling a hot rolled steel strip.
    [0002] The present application claims priority based on Japanese Patent Application Number 2009-285121 filed in Japan on December 16, 2009, the contents of which are incorporated herein by reference. FUNDAMENTALS OF THE TECHNIQUE
    [0003] In a hot rolling process, a hot rolled steel strip which has passed through a finishing rolling process (hereinafter, also referred to as "steel strip") is transported from a rolling mill finish lamination to a lower winder. During this transport the steel strip is cooled to a predetermined temperature by means of a cooling device formed by plural cooling units and then, it is wound by the lower winder. At the time of hot rolling the steel strip, the cooling mode of the steel strip after passing through the finish rolling process to winding is an important factor in determining the mechanical properties of the steel strip. In general, the steel strip is cooled, for example, using water as a cooling medium (hereafter also referred to as "cooling water"). In recent years, cooling is performed in a high temperature range at a high cooling speed (hereinafter, also referred to as "quick cooling"), for the purpose of maintaining workability and strength more than or equal to those of conventional steel strip while reducing additional elements such as manganese in the steel strip. Also, from the standpoint of maintaining cooling uniformity, a cooling method is known which avoids cooling in a transitional boiling state, which is a primary factor of non-uniformity in cooling as much as possible, and employs a cooling in a nucleate boiling state, under which a stable cooling capacity can be obtained. In general, cooling in the boiling nucleate state is rapid cooling.
    [0004] In the finish lamination process, an accelerated lamination and a decelerated lamination are widely employed. A transport speed of the steel strip on the output side of the finishing rolling mill is equal to a transport speed to the lower winder, and the steel strip is cooled to a state where the transport speed changes. Therefore, in general, when the hot rolled steel strip is cooled using blast chilling, the cooling length and water quantity density of the cooling water are changed according to an increase or a decrease in the transport speed of the steel strip so as to achieve a target coiling temperature of the steel strip. For example, Patent Document 1 describes a method for cooling in which, after rolling a final finish roll, the length of the cooling zone is adjusted according to an increase or a decrease in the rolling speed of a steel plate hot rolled so that the amount of decrease in temperature of the steel plate is constant within the steel plate. This method includes: a rapid cooling step of rapidly cooling the steel plate under a condition of a water quantity density of 1000 L/min/m2 or more; and a sluggish cooling step of slowly cooling the hot rolled steel plate after the blast chilling step so that the steel plate is wound to a predetermined steel plate winding temperature.
    [0005] Further, Patent Document 2 describes a technique in which a cooling water with a water quantity density of 2.0 m3/m2min or more is supplied, and the length of a cooling zone is adjusted by switching ON - OFF independently each cooling head of a first group of cooling heads and a second group of cooling heads according to an increase in transport speed. DOCUMENT OF THE TECHNIQUE RELATING TO PATENT DOCUMENTS
    [0006] Patent Document 1: Unexamined Japanese Patent Application, First Publication Number 2008-290156
    [0007] Patent Document 2: Japanese Patent Publication Number 4449991 DESCRIPTION OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION
    [0008] However, with the invention described in Patent Document 1, it was found that in the case where the length of cooling performed by the cooling device was changed in accordance with a change in the transport speed of the rolled steel strip hot, for example, by controlling the opening and closing of valves provided in the cooling device, the amount of cooling of the steel strip changed greatly according to an increase or a decrease in the cooling length, causing the temperature of the strip to steel after rapid cooling changed significantly. Therefore, even if the water supply is controlled in the post-cooling process, the deviations in steel strip temperatures that occur in the blast-cooling process cannot be prevented, whereby it is extremely difficult to control the strip winding temperature. steel within the target temperature range of the steel strip.
    [0009] Furthermore, it was also found that in the case where part of the blast chilling process was performed with air cooling at the time when the water supply was controlled in the blast chilling process, for example by closing some of the valves for the supply of the cooling water, the cooling water entered the air-cooled area of another water supply area, which is a major factor in causing a cooling non-uniformity. It may be possible to solve the problem described above, for example, by increasing the number of drain units in the cooling device to prevent cooling water from entering the area to be air-cooled. However, in the case of rapid cooling that requires a large amount of cooling water, a drainage water installation is required to have a high capacity, and with this, this method is not desirable due to limitations and installation cost.
    [00010] In the case where the technique described in Patent Document 2 was employed in a state where the transport speed of the hot rolled steel strip changes under the transition boiling state status where the ability to cool the steel strip changes greatly, it was found that the deviation of the steel strip winding temperature increased for the above-described reason.
    [00011] The present invention was made in view of the reasons described above, and an object of the present invention is to provide a method for cooling a hot rolled steel strip capable of, in cooling the hot rolled steel strip after the rolling of finishing in the hot rolling process, precisely and uniformly cool the hot rolled steel strip transported from the finish rolling mill at a conveying speed with acceleration and deceleration to a predetermined coiling temperature of the steel strip. MEANS TO SOLVE PROBLEMS
    [00012] The present invention employs the following methods to solve the problems described above.
    [00013] A first aspect of the present invention provides a method for cooling a hot rolled steel strip after a finish rolling in which the conveyor speed varies, the method including: adjusting a conveyor speed change schedule with basis on a temperature of a steel strip before finishing rolling and a condition of finishing rolling; performing a first cooling in which the hot rolled steel strip is cooled under a film boiling state in a first cooling section; perform a second cooling in which the hot rolled steel strip is cooled to a water quantity density not less than 2 m3/min/m2 in a second cooling section; and coil the hot rolled steel strip. In this method, a cool-down condition is controlled in the first cool-down such that a target temperature T2a of the steel strip at an inlet side in the second cooling section before a change in a transport speed, a target temperature T2a' of the strip of steel on an inlet side of the second cooling section after a change in transport speed and an amount of change ΔTx of a cooling amount of the hot rolled steel strip in the second cooling section, the amount of change being caused by change in transport speed, satisfies 0.8 < (T2a' - T2a)/ΔTx < 1.2 (Equation 1).
    [00014] According to the method for cooling a hot rolled steel strip of (1) above, a variation range in a cooling length in the second cooling section can be in the range of 90% to 110% regardless of a change in transport speed.
    [00015] According to the method for cooling a hot rolled steel strip of (1) or (2) above, a range of variation in the density of water quantity in the second cooling section can be in the range of 80% to 120% regardless of a change in transport speed.
    [00016] According to the method for cooling a hot rolled steel strip of any one of (1) to (3) above, the cooling under a nucleate boiling state accounts for not less than 80% of the duration in the second cooling section.
    [00017] According to the method for cooling a hot rolled steel strip of any one of (1) to (4) above, the method may further include: performing a third cooling in a third cooling section disposed after the second cooling section, the third cooling being performed by cooling with a cooling water of a water quantity density not less than 0.05 m3/min/m2 and not greater than 0.15 m3/min/m2 and cooling with outside air.
    [00018] According to the method for cooling a hot rolled steel strip of any one of (1) to (5) above, the method may further include: adjusting a cooling length in the second cooling section based on a maximum transport speed value in the transport speed change schedule; and adjust the target steel strip temperature T2a on the inlet side in the second cooling section based on a minimum conveyor speed value in the conveyor speed change schedule.
    [00019] According to the method for cooling a hot rolled steel strip of any one of (1) to (6), the method may further include: measuring an inlet side temperature of the steel strip on the side entry into the second cooling section; and changing the cooling condition in the first cooling section based on the measured inlet side temperature of the steel strip, and controlling the inlet side temperature of the steel strip so as to fall within a predetermined range.
    [00020] According to the method for cooling a hot rolled steel strip of any one of (1) to (7) above, the method may further include: measuring an exit side temperature of the steel strip on the side outlet in the second cooling section; and changing a cooling condition in a third cooling section disposed after the second cooling section based on the measured output side temperature of the steel strip, and controlling a steel strip winding temperature to fall within a predetermined range .
    [00021] According to the method for cooling a hot rolled steel strip of any one of (1) to (8) above, the second cooling section may include a front cooling section, a medium cooling section, and a rear cooling section, and the method may further include: measuring an outlet side temperature of the steel strip on an outlet side of the front cooling section; and changing a cooling condition in the average cooling section based on the measured output side temperature of the steel strip in the front cooling section, and controlling temperature of the steel strip in an inlet side of the rear cooling section to fall in. of a predetermined range. EFFECTS OF THE INVENTION
    [00022] According to the method described in (1) above, it is possible to suppress the variation in cooling caused by an increase/decrease in the cooling length and cooling water flow of the steel strip. Specifically, it is possible to suppress the variation in cooling in the temperature range of the steel strip (from 300°C to 700°C) which corresponds to the transition boiling state and the nucleate boiling state where the cooling capacity ( cooling speed) changes abruptly controlling the cooling condition in the first cooling step so as to satisfy Equation 1 above according to the change in the transport speed, and adjusting the cooling condition in the second cooling step to be approximately constant.
    [00023] According to the method described in (2) above, it is possible to suppress the variation in cooling caused by the flow of cooling water over the steel strip and to suppress the deviation of the cooling temperature of the steel strip, limiting the range of variation in cooling length in the second cooling section.
    [00024] According to the method described in (3) above, it is possible to suppress the variation in the cooling capacity (cooling speed) in the second cooling section and suppress the deviation of the steel strip winding temperature, limiting the range of variation of the cooling quantity density.
    [00025] According to the method described in (4) above, how is it possible to minimize the variation in cooling caused by cooling under the transition boiling state and suppress the temperature deviation of the steel strip on the outlet side in the second section of cooling, it is possible to suppress the deviation of the cooling temperature of the steel strip
    [00026] According to the method described in (5) above, it is possible to suppress the deviation of the steel strip winding temperature, reducing the cooling water quantity density in an outlet side section of the second cooling section for winding.
    [00027] According to the method described in (6) above, as the temperature of the steel strip on the inlet side in the second cooling section is appropriately adjusted based on the conveyor speed change schedule, it is possible to favorably suppress the deviation of the steel strip winding temperature.
    [00028] According to the method described in any one of (7) to (9) above, it is possible to additionally favorably suppress the steel strip winding temperature by performing the direct feed control and the return control based on the actually measured steel strip temperatures. BRIEF DESCRIPTION OF THE DRAWINGS
    [00029] Figure 1 is a diagram schematically illustrating a configuration of a finishing lamination mill and subsequently a hot rolling installation that has a cooling device according to a modality.
    [00030] Figure 2 is a diagram schematically illustrating a flow to determine cooling conditions. Where (1) means “TARGET TEMPERATURE ON THE INLET SIDE OF COOLING SECTION 20”; where (2) means “OUTLET SIDE TARGET TEMPERATURE IN COOLING SECTION 20”; where (3) means “TARGET WINDING TEMPERATURE”; where (A) means “FINISH ROLL CONDITION (STEEL STRIP THICKNESS, TARGET TEMPERATURE ON OUTLET SIDE OF FINISH ROLL LAMINATOR, AND SIMILARS)”; where (B) means in the “STEEL STRIP PROPERTY VALUE”; where (C) means “COOLING PROPERTIES OF STEEL STRIP (THERMAL CONDUCTIVITY).
    [00031] Figure 3 is a schematic view illustrating an example of a transport speed change schedule.
    [00032] Figure 4 is a schematic view of a temperature history during a cooling process.
    [00033] Figure 5 is a schematic view of a temperature history during the cooling process.
    [00034] Figure 6 is a schematic view illustrating a mode of cooling a steel strip.
    [00035] Figure 7 is a diagram illustrating a transport speed change schedule used in an example. MODALITIES OF THE INVENTION
    [00036] The present inventors have found that, at the time when a hot rolled steel strip that has passed through a finishing roll is cooled through a first cooling step and a second cooling step, which is one step of a rapid cooling, in a hot rolling process in which a transport speed varies, it is possible to suppress the deviation of steel strip winding temperatures by controlling the water supply in the first cooling step so as to make the cooling conditions such as the cooling length and density amount of water unchanged as much as possible in the second cooling step regardless of changes in conveying speed, even when the conveying speed of the hot rolled steel strip varies. More specifically, the present inventors have found that it is possible to suppress the steel strip winding temperature drift by controlling the cooling conditions in the first step so as to satisfy: 0.8 < (T2a' - T2a)/ΔTx < 1.2 (Equation 1),
    [00037] where T2a is a target temperature of the hot rolled steel strip on the inlet side in a second cooling section before the conveying speed varies; T2a' is a target temperature of the hot rolled steel strip on the inlet side of the second cooling section after the conveying speed varies; and ΔTx is the amount of change in the amount of hot rolled steel strip cooling in the second cooling section, the change being due to the occurrence of the change in rolling speed.
    [00038] Here below, with reference to the drawings, a description will be made of a cooling device 1 and a method for cooling a steel strip S according to an embodiment of the present invention based on the above-described findings.
    [00039] Figure 1 schematically illustrates a configuration of a finishing lamination laminator 2 and later a hot rolling installation that has the cooling device 1 according to this modality.
    [00040] As illustrated in figure 1, the hot rolling installation includes the finishing rolling mill 2, a cooling device 1, and a winder 3, which are arranged in this order in the direction of transport of the steel strip S The finish rolling mill 2 continuously rolls steel strip S that has been discharged from a heating furnace (not shown) and has been rolled by a rough rolling mill (not shown) with the continuous rolling being accelerated or decelerated according to the transport speed change schedule. The cooling device 1 cools the steel strip S after a finish rolling to a predetermined steel strip winding temperature of, for example, 300°C. Winder 3 reels the cooled S steel strip. A thermometer 51 for measuring a finishing rolling temperature T0 of the steel strip is provided on the upstream side of the finishing rolling mill 2, and an output table 4 formed by table rollers 4a is provided between the finishing mill. finish rolling mill 2 and winder 3. The steel strip S which has been rolled by finish rolling mill 2 is cooled by cooling device 1 while being transported over output table 4, and then being wound by winder 3.
    [00041] A first cooling unit 10a which cools, in a first cooling section 10, the steel strip S immediately after passing through the finishing rolling mill 2 is provided on the upstream side in the cooling device 1, in others words, in a position immediately downstream of the finish lamination laminator 2. As illustrated in figure 1, the first cooling unit 10a is provided with plural laminar nozzles 11 which spray the cooling water, for example, onto a surface of the steel strip S, the laminar nozzles being arranged in the width direction and transport direction of the steel strip S. The water quantity density of the cooling water sprayed from the laminar nozzles 11 over the surface of the steel strip S is adjusted, for example, to 0.3 m3/m2/min. The first cooling section 10 refers to a section in which the steel strip S is cooled under a boiling film state by the first cooling unit 10a. In addition to spraying the cooling water through the laminar nozzles, the cooling in the first cooling section 10 can be carried out, for example, by spraying the cooling water through a spray nozzle, by gas cooling using an air nozzle, by a combination of gas and water using a gas-water nozzle (mist cooling), or by air cooling in which no cooling medium is supplied. Note that "cooled under a film boil state" includes a cool state where cooling in the film boil range is performed on a part of the first cooling section while air cooling is performed on the remainder of the section in addition of a state where cooling under the film boil state is performed on the entire first cooling section.
    [00042] As illustrated in figure 1, on the downstream side of the first cooling unit 10a, a second cooling unit 20a is provided which rapidly cools, in the second cooling section 20 (fast cooling section), the steel strip S which was cooled in the first cooling section 10. The second cooling section 20 refers to a section in which the second cooling unit 20a cools the steel strip S. The term "quickly cools" as used in this modality refers to a process of cooling in which the cooling water quantity density is adjusted to at least 2 m3/min/m2 or more, desirably to 3 m3/min/m2 or more. The term "cooling water quantity density" means the quantity of cooling water supplied per 1 m2 unit on the target surface of the steel strip, and in the case of cooling only the upper surface of the steel strip, it means the quantity of cooling water supplied per 1 m2 unit on the upper surface of the steel strip. The second cooling unit 20a is provided, for example, with spray nozzles 21 which spray the cooling water over the upper surface of the steel strip S while being arranged in the transport direction and in the width direction of the steel strip, and has an ability to provide the cooling water quantity density, for example, of 2 m3/min/m2, desirably 3 m3/m2/min or more for steel strip S. With respect to the entire cooling mode in this second cooling section, second cooling unit 20a has a capacity to cool 80% or more of the cooling duration in the second cooling section under nucleate boiling.
    [00043] As illustrated in figure 3, a third cooling unit 30a that cools a third cooling section 30 can be provided on the downstream side of the second cooling unit 20a. Similar to the first cooling unit 10a, the third cooling unit 30a is provided with plural laminar nozzles 11 which spray the cooling water over the surface of the steel strip S while being arranged in the width direction and in the strip transport direction. of steel S. The water quantity density of the cooling water sprayed from the laminar nozzles 11 over the surface of the steel strip S is adjusted, for example, to 0.3 m3/m2/min. In addition to spraying the cooling water through the laminar nozzles, the cooling in the third cooling section 30 can be carried out, for example, by spraying the cooling water through a spray nozzle, by gas cooling using an air nozzle, by a combination of gas and water using a gas-water nozzle (mist cooling), or by air cooling in which no cooling medium is provided.
    [00044] Thermometers 52, 53 for measuring a steel strip temperature on the inlet side and a steel strip temperature on the outlet side are provided on the inlet side and on the outlet side of the first cooling section 10, respectively . Furthermore, a thermometer 54 for measuring a steel strip temperature of the output side is provided on the output side of the second cooling section 20. A thermometer 55 for measuring a steel strip winding temperature is provided on the upstream side of the winder 3. Steel strip temperatures at the time of steel strip cooling are measured on an as-needed basis, a direct feed control and a return control are performed on the first cooling section 10 and the third cooling section 30 based on the measured values of the thermometers.
    [00045] In the following, with reference to figure 2 to figure 6, a description will be made of a method for cooling the hot rolled steel strip S according to this modality, the method at least including a first cooling step, a second cooling step, and a winding step. Note that the description will be made on the assumption that the third cooling unit 30a is provided.
    [00046] Figure 2 illustrates a flow to determine the cooling conditions in the second cooling section 20 at the time of starting the hot rolled steel strip cooling.
    [00047] The steel strip after completion of rough rolling is transported to the finishing rolling mill 2, and its finishing rolling steel strip temperatures are measured by thermometer 51. The measured temperatures data are entered in a computing unit 101 based on the temperatures of the steel strip and a predetermined finish rolling condition such as thickness, which has been entered in advance, the computing unit 101 obtains a conveyor speed change schedule (the speed in the output side of the finish rolling mill) at positions in the longitudinal direction of the steel strip in such a way that the conveyor speed change schedule satisfies the predetermined finish rolling condition, as illustrated in figure 3. The change schedule of transport speed can be obtained so as to be associated with the positions in the longitudinal direction of the steel strip, in addition to with time. from the start of the finish lamination.
    [00048] The transport speed change schedule obtained by the computing unit 101 is sent to a computing unit 102. The computing unit 102 adjusts, for example, cooling conditions such as the density of cooling water quantity and the length of the cooling in the second cooling section 20, and an initial cooling condition in the first cooling section 10, which are necessary to adjust the respective temperatures of the steel strip so as to fall within the target range, based on the conveyor speed change schedule, a target steel strip winding temperature T4, which was entered in advance, the input side target steel strip temperature T2a, and the output side target steel strip temperature T2b in the second cooling section 20 and the like. As the cooling capacity (cooling speed) can be expressed as a function of water quantity density, it is possible to adjust the density it is possible to adjust the required water quantity density and the cooling length by obtaining the time required to pass through of the cooling section based on the transport speed change schedule. Certain types of steel are desirable to be cooled at a predetermined cooling rate for the purpose of improving the properties of the steel. For such steels, the required cooling length can be obtained based on the required water quantity density for the required cooling speed and the conveyor speed change schedule. In a similar way, it is possible to adjust the initial cooling conditions in the first cooling section 10 and the third cooling section 30 based on the target steel strip winding temperature T4, the target steel strip temperature T2b on the side. output of the second cooling section, the target steel temperature T2a on the inlet side of the second cooling section, and the target steel strip temperature T0a on the output side of the finishing mill.
    [00049] In the continuous cooling process in the first cooling section 10 and the third cooling section 30, the cooling conditions such as the water quantity density and the cooling length are changed by controlling the water supply so as to be associated with the change in transport speed. More specifically, by adjusting the target steel strip temperature T2a' on the inlet side in the second cooling section in time when the transport speed reaches the second transport speed in a mode that satisfies Equation 1 described above, the supply of water is controlled in the first cooling section so as to be able to achieve this target steel strip temperature setting value during the process that transitions from the first conveyor speed to the second conveyor speed. For example, in Figure 3, it is assumed that the transport speed at time B is set to the first transport speed, and the transport speed at time C is set to the second transport speed. For example, in the case where the target winding temperature T4 of the steel strip is 450°C, the target temperature T2b of the steel strip on the output side in the second cooling section 20 is set to 480°C, and the temperature target T2a of the steel strip on the inlet side in the second cooling section 20 is set to 600°C as the cooling conditions in the first transport speed. At the time of setting T2a and T2b, the cooling capacities in the first cooling section 10, the second cooling section 20 and the third cooling section 30, the starting temperature of the transition boiling range of the steel strip and similar ones are taken into account. From the above setting values, the amount of steel strip cooling in the second cooling section 20 at the first transport speed is T2a - T2b = 120°C, and the cooling conditions such as the cooling length and the density of amounts of water in the second cooling section are determined so as to be able to achieve the equation.
    [00050] During a continuous cooling process in which the transport speed transitions to the second transport speed, the transport speed changes with the advancement of the finishing mill, as illustrated in figure 3. On the other hand, the quantity Cooling Tx in the second cooling section 20 (in other words T2ax - T2bx) varies as illustrated in figure 5 in the case where T2ax and the cooling conditions in the second cooling section (cooling length and water quantity density of cooling) remain unchanged, and a difference in the amount of cooling can be expressed as ΔTx (in other words, Tx2 - Tx1) during the transition to the second transport speed. Therefore, when transitioning from the first transport speed to the second transport speed, it is necessary to adjust the target temperature of the steel strip on the inlet side in the second cooling section and perform an adjustment controlling the water supplied in the first cooling section , taking into account the amount of change in Tx. The adjustment described above is made in consideration of the control accuracy in cooling section 1 in the range that falls within 0.8 < (T2a' - T2a)/ΔTx < 1.2, desirably 0.9 < (T2a' - T2a)/ΔTx < 1.1, where T2a is the target temperature of the steel strip on the inlet side of the second cooling section at the first transport speed, and T2a' is the target temperature of the steel strip on the inlet side of the second cooling section after the transport speed become the second transport speed. The target temperature T2a" of the steel strip on the inlet side in the second cooling section during the transition from the first transport speed to the second transport speed can be expressed as a function of time based on T2a and T2a'. By For example, the function can be given as values associated with time, using the time required to transition from the first transport speed to the second transport speed, and the average amount of change in temperatures per unit time ((T2a' - T2a) /t). Also, in Figure 3, in the case where the first transport speed is a transport speed at time A and the second transport speed is a transport speed at time B, the transport speed is constant during the transition from time A to time B, and with this, ΔTx is zero in this transition. Therefore, T2a = T2a' is established during the transition from time A to time B. The water supply is controlled by the cooling section o 1 so as to be setting T2a', and the steel strip is cooled in the second cooling section in a state where the cooling conditions such as the cooling length and/or the water quantity density are substantially constant. Note that the phrase "substantially constant" means that the amount of change in cooling length falls within the range of 90% to 110%, and the amount of change in water quantity density falls within the range of 80% to 120% . Still, in a similar way, in the case where the transport speed programming is obtained with respect to the longitudinal direction of the steel strip, it is possible to set a new target steel strip temperature T2a' so as to be associated with the positions in the longitudinal direction of the steel strip.
    [00051] As cooling in the film boiling range is performed in the first cooling section 10, it is possible to precisely achieve the temperature of the steel strip on the outlet side in the second cooling section by controlling the water supply according to the change in the transport speed, and make the cooling length and cooling water quantity density of the second cooling unit 20a almost unchanged in the second cooling section 20. This makes it possible to: remove the external cooling disturbance caused by water ingress that exists over the steel strip resulting from the ON/OFF of the water supply valve; suppressing the temperature deviation of the steel strip on the outlet side in the second cooling section; and precisely reach the coiling temperature of the steel strip.
    [00052] The temperature range in which the cooling conditions are constant in the second cooling section can be set in the range of 300°C to 700°C, and more desirably, in the range of 400°C to 600°C . This is because it is possible to further reduce the steel strip winding temperature drift by reducing the time required to cool under transition boiling in the second cooling section. As illustrated in figure 6, in the case where the water quantity density in the second cooling section 20 is 3 m3/min/m2 and the water quantity density in the first cooling section 10 is 0.3 m3/m2/min , cooling under transition boil (B) starts at steel strip temperatures of approximately 700°C and approximately 600°C, respectively, and cooling under film boil (A) is performed in the strip temperature range higher than these temperatures. With film boiling cooling, it is possible to achieve a stable cooling capacity (heat transfer coefficient) irrespective of steel strip temperatures. On the other hand, with cooling under transition boiling, the deviation of steel strip temperatures increases, because the cooling capacity abruptly increases due to a decrease in the steel strip temperature, which further accelerates the cooling in the portions of lower temperature.
    [00053] Therefore, by cooling, in the first cooling section 10, the steel strip to the lowest temperature (600°C) at which the cooling is performed under film boiling and then performing blast cooling in the second section of cooling 20, it is possible to reduce the time required for cooling under transition boiling in the second cooling section, whereby it is possible to reduce the variation in cooling caused by performing the cooling under transition boiling state. With this process, it is possible to stably obtain the steel strip temperature on the outlet side in the second cooling section, whereby it is possible to further reduce the deviation of the steel strip cooling temperature.
    [00054] The steel strip cooling mode illustrated in figure 6 will be described in more detail. In the case where the temperature of the steel strip is higher than 700°C and the blast chilling is performed with the water quantity density of 3 m3/min/m2, the cooling of the steel strip is performed under the boiling of film (A) under which the cooling capacity of the steel strip (heat transfer coefficient) is small. Therefore, the flow of cooling water over the steel strip and the change in the cooling length, which does not follow the change in transport speed, has a small impact on the deviation of the steel strip winding temperature. Furthermore, rapid cooling in the temperature range lower than 300°C does not provide sufficient effects if the amount of investment in the facility is compared with the effect thus obtained in terms of material properties. In general, the rapid cooling of the steel strip in the temperature range of 300°C to 700°C provides an advantage in obtaining predetermined material properties. However, in this temperature range, the steel strip is cooled under transition boiling (B) and nucleate boiling (C). In transition boiling, the cooling capacity of the steel strip increases abruptly with decreasing steel strip temperature, while cooling under the nucleate boiling state provides a cooling capacity five to almost 10 times greater than that. obtained in the boiling state of film when run by the same amount of water. More specifically, the flow of cooling water over the steel strip, and the change in cooling length, which does not follow the change in transport speed, has a great impact on the uniformity of steel strip winding temperatures, and with this, it is important to prevent the cooling water flow from occurring over the steel strip and the change in the cooling length in this temperature range in order to improve the uniformity of the steel strip winding temperatures.
    [00055] At the time when the cooling conditions in the second cooling section 20 are determined, it is possible to determine the cooling length based on the maximum value of the transport speed in the transport speed change schedule, and adjust the initial value of the target temperature T2a of the steel strip on the inlet side in the second cooling section based on the minimum transport speed value in the transport speed change schedule. An example thereof includes a case where the steel strip temperature on the inlet side in the second cooling section 20 in continuous cooling is desired to be a certain value or more.
    [00056] In the following, a description will be made of a method to adjust the initial cooling conditions in the second cooling section 20 by determining the cooling length based on the maximum transport speed value in the transport speed schedule, and setting a initial value of the target temperature T2a of the steel strip on the inlet side in the second cooling section based on the minimum value of the transport speed. In Figure 3, the transport speed increases and decreases in an approximately straight line accelerating and decelerating from the front end to the rear end of the steel strip. In Figure 3, the minimum value of the transport speed is denoted by V(min), the maximum value is denoted by V(max), and the speed at the end of the finishing roll is denoted by V(fin).
    [00057] As described above, for example, the amount of cooling in the second cooling section 20 is T2a - T2b = 120°C in the case where the target cooling temperature T4 of the steel strip is set to 450°C, the target temperature T2b of the steel strip on the outlet side of the second cooling section 20 is set to 480°C, and the target temperature T2a of the steel strip on the inlet side of the second cooling section 20 is set to 600°C . For steel strip transport speed, V(min) is 400 m/min, V(max) is 600 m/min and V(fin) is 520 m/min, for example. As the initial settings of the cooling conditions in the second cooling section 20 under which the 120°C cooling can be achieved in time when the steel strip is conveyed at 600 m/min, the amount of cooling water is adjusted, for example, to 3 m3/min/m2, and the cooling length is set to 3 m.
    [00058] In the case where the cooling is performed under the cooling conditions described above, the time required for cooling is 1.5 times longer than the transport speed time being 400 m/min, which is the value Minimum. Therefore, the amount of cooling increases by approximately 60°C, so the amount of cooling in the second cooling section 20 is approximately 180°C. As it is desirable to set the output side steel strip temperature T2b at the second cooling section 20 to be constant, the initial setting of the target steel strip temperature T2a at the inlet side at the second cooling section 20 is set to 660 °C, which is 60°C higher than 600°C.
    [00059] In the acceleration section, the amount of cooling T2a - T2b in the second cooling section 20 decreases, and with it, in response to the acceleration, the target temperature T2a' of the steel strip on the inlet side in the second cooling section it is made lowered from the temperature of 600°C according to the change in transport speed. Then, at the moment when the conveying speed reaches the maximum speed, the target temperature T2a' of the steel strip on the inlet side in the second cooling section 20 is 600°C.
    [00060] When the finishing mill advances further and enters the deceleration section, the amount of quench T2a - T2b in the second quench section 20 increases, and thus the target temperature T2a of the steel strip on the inlet side in the second section cooling temperature is increased again by 600°C. As the velocity V(fin) at the end of the rolling is V(min) < V(fin) < V(max), the ratio on the inlet side of the second cooling section 20 between the target steel strip temperature T2a(Vmax ) at maximum speed, target steel strip temperature T2a(Vmin) at minimum speed and target steel strip temperature T2a(Vfin) at the end of rolling is T2a(Vmax) < T2a(Vfin) < T2a( Vmin).
    [00061] As described above, the cooling conditions in the second cooling section 20 are adjusted so that the cooling length is determined based on the maximum value of the transport speed, and the initial value of the target temperature T2a of the steel strip on the inlet side in the second cooling section is adjusted based on the minimum value of the transport speed. With this setting, the target temperature T2a of the steel strip on the inlet side in the second cooling section can always be made higher than the T2a(ini), which is the initial setting value, in the continuous cooling process in the which transport speed varies. In the case where the cooling of the second cooling section is started from a temperature in the vicinity of the temperature at which the cooling under transitional boiling in the first cooling section 10 is started, it is possible to avoid the cooling under transitional boiling in the first section cooling 10.
    [00062] In the second cooling section 20, cooling is performed with the cooling length and/or water quantity density being constant regardless of the transport speed; in the first cooling section 10 and in the third cooling section 30, the water supply is controlled based on the transport speed by opening and closing the valve, to cool the steel strip to a predetermined winding temperature of the steel strip. steel; and then, the steel strip is wound by the winder.
    [00063] To control the water supply in the first cooling section 10 and the third cooling section 30, it is desirable that thermometers be provided on the inlet side and on the outlet side of the second cooling section 20, and that the control return and direct feed control are performed using the values of the thermometers. Using the actually measured steel strip temperatures in the control, it is possible to precisely achieve the target steel strip temperature T2a on the inlet side in the second cooling section, and the steel strip winding temperature.
    [00064] When determining the cooling conditions in the second cooling section, it may be possible to determine the cooling water quantity density in advance, and then obtain the cooling length so that the required amount of cooling T2a - T2b can be achieved. For example, it may be possible to designate in advance certain types of steels as steels to be cooled with the cooling water quantity density of 3 m3/min/m2, and then determine the cooling length.
    [00065] In the second cooling section, it is possible to perform the cooling with the amount of cooling water and the cooling length with which cooling under the nucleate boiling range accounts for 80% or more. This makes it possible to suppress the variation in temperatures caused by cooling under transition boiling, and to cool the target in a uniform way.
    [00066] The second cooling section can be divided into a front cooling section, a middle cooling section, and a rear cooling section. In this case, the steel strip temperatures on the outlet side are measured on the outlet side of the front cooling section. Based on the output side steel strip temperature measured in the front cooling section, the cooling conditions in the middle cooling section are changed, and the steel temperature in the inlet side of the rear cooling section is controlled so as to falls within a predetermined range, whereby it is possible to favorably suppress the deviation of the coiling temperature of the steel strip.
    [00067] In the third cooling section 30, it may be possible to perform cooling with the water quantity density of the cooling water in the range of 0.05 m3/min/m2 to 0.15 m3/min/m2. The cooling in the third cooling section 30 can be carried out by supplying the cooling water as the cooling medium, a gas or a mixture thereof, as well as by air-cooling in which no cooling medium is supplied. This is because, by reducing the water quantity density, it is possible to improve the controllability in cooling, whereby it is possible to precisely reach the coiling temperature of the steel strip. EXAMPLES
    [00068] In the following, a description will be made of Examples A1 to A7, Examples B1 to B7, Examples C1 to C7, and Examples D1 to D7, each of which employs the finish laminating laminator, the first cooling unit, the second cooling unit, and the winder.
    [00069] In each of the Examples, a hot rolled steel strip was subjected to finish rolling according to the conveyor speed change schedule illustrated in figure 7, and then subjected to the first quench and the second quench. Table 1 shows the cooling conditions and evaluation results of the Examples. In figure 7, t = 0 indicates a moment when the upper end portion of the hot rolled steel strip reaches the first cooling section, t = 90 indicates a moment when the rear end portion of the hot rolled steel strip reaches the winder. In the present Examples, the evaluation was done by setting the first transport speed to be a transport speed at t = 20, and setting the second transport speed to be a transport speed at t = 50. It should be noted that the temperature steel strip target on the output side in the second cooling section is set to 400°C. TABLE 1

    [00070] In Table 1, the "steel strip temperature offset at the inlet side in the second cooling section" and the "steel strip winding temperature offset" each refer to the temperature offset obtained by continuously measuring the temperatures from the center of the steel strip width in the direction in which the steel strip moves.
    [00071] In the present Examples, as the steel strip was air cooled from the outlet of the second cooling section to the winding, the deviation of the steel strip temperature on the outlet side of the second cooling section is considered to be almost equal to deviation of the steel strip winding temperature.
    [00072] The results of these examples confirm that the effect of suppressing the deviation of the steel strip winding temperature can be obtained by setting the target temperature t2a' of the steel strip on the inlet side in the second cooling section so that the value of (T2a'-T2a)/ΔTx falls within the range of 0.8 to 1.2.
    [00073] Furthermore, the results of Examples C1 to C7, which are comparative examples, confirm that even setting the target temperature T2a' of the steel strip on the inlet side of the second cooling section so that the value of ( T2a'-T2a)/ΔTx falls within the range of 0.8 to 1.2, the effect of suppressing the steel strip winding temperature deviation cannot be obtained in the case where the water quantity density in the second cooling section is less than 2.0 m3/min/m2.
    [00074] As described above, the preferred embodiment of the present invention has been described with reference to the accompanying drawings. However, the present invention is not limited to examples. Apparently, the person skilled in the art can achieve several examples of change or examples of modification within the scope of the Claimed technical principle. It is understood that these examples of changes or examples of modifications are naturally included within the scope of the present invention. INDUSTRIAL APPLICABILITY
    [00075] According to the present invention, it is possible to precisely and uniformly cool a hot rolled steel strip transported from a finishing rolling mill at a transport speed with deceleration acceleration, to reach a predetermined strip coiling temperature of steel. REFERENCE LISTING 1 Cooling device 2 Finish laminating laminator 3 Winder 4 Output table 4a Table roller 10 First cooling section 10a First cooling unit 11 Laminar nozzle 20 Second cooling section (fast cooling section) 20a Second unit cooling unit (fast cooling unit) 21 Spray nozzle (over top surface side) 30 Third cooling section 30a Third cooling unit 40 Control unit 51, 52, 53, 54, 55 Thermometer S Steel strip V( min) Minimum transport speed V(max) Maximum transport speed V(fin) Transport speed at the end of the finishing roll T2a(Vmin) Target temperature of the steel strip on the inlet side of the second cooling section in the Minimum transport speed T2a(Vmax) Target steel strip temperature at inlet side of second cooling section at maximum transport speed T2a(Vfin) Target strip temperature of steel on the inlet side of the second cooling section with respect to a transport speed at the end of the finishing roll (A) Cooling under film boil (B) Cooling under transition boiling (C) Cooling under nucleate boil
    权利要求:
    Claims (9)
    [0001]
    1. Method for cooling a hot rolled steel strip (5) after a finish rolling in which a conveyor speed varies, the method characterized by the fact that it includes: adjusting a conveyor speed change schedule based on a temperature of a steel strip before finishing rolling and a condition of finishing rolling; performing a first cooling in which the hot-rolled steel strip (5) is cooled under a film boiling state in a first cooling section (10); performing a second cooling in which the hot-rolled steel strip (5) is cooled to a water quantity density not less than 2 m3/min/m2 in a second cooling section (20); and winding the hot rolled steel strip (5) in which a cooling condition is controlled in the first cooling so that a target temperature T2a of the steel strip (5) at an inlet side in the second cooling section ( 20) before a change in a transport speed, a target temperature T2a' of the steel strip on an inlet side of the second cooling section (20) after a change in rolling speed, and a change amount ΔTx of one cooling amount of the hot rolled steel strip (5) in the second cooling section (20), the amount of change being caused by the change in rolling speed, satisfies 0.8 < (T2a' - T2a)/ΔTx < 1 ,2 (Equation 1).
    [0002]
    2. Method according to claim 1, characterized in that a range of variation in a cooling length in the second cooling section (20) may be in the range of 90% to 110% regardless of a change in transport speed.
    [0003]
    3. Method according to claim 1 or 2, characterized in that a range of variation in the density of water quantity in the second cooling section (20) can be in the range of 80% to 120% regardless of a change in transport speed.
    [0004]
    4. Method according to any one of claims 1 to 3, characterized in that the cooling under a nucleate boiling state is responsible for not less than 80% of the cooling duration in the second cooling section (20).
    [0005]
    5. Method according to any one of claims 1 to 4, the method characterized in that it further includes: performing a third cooling in a third cooling section (30) arranged after the second cooling section (20), the third cooling being formed by cooling with a cooling water of a water quantity density not less than 0.05 m3/min/m2 and not greater than 0.15 m3/min/m2 and cooling with outside air.
    [0006]
    6. Method according to any one of claims 1 to 5, the method characterized in that it further includes: adjusting a cooling length in the second cooling section (20) based on a maximum value of the transport speed in the schedule of transport speed change; and adjust the target temperature T2a of the steel strip (5) on the inlet side in the second cooling section (20) based on a minimum transport speed value in the transport speed change schedule.
    [0007]
    7. Method according to any one of claims 1 to 6, the method characterized in that it further includes: measuring an inlet side temperature of the steel strip (5) on the inlet side in the second cooling section (20 ); and change the cooling condition in the first cooling section (10) based on the measured inlet side temperature of the steel strip (5), and control the inlet side temperature of the steel strip (5) to fall within a predetermined range.
    [0008]
    8. Method according to any one of claims 1 to 7, the method characterized in that it further includes: measuring an outlet side temperature of the steel strip (5) on the outlet side in the second cooling section (20 ); and changing a cooling condition in a third cooling section (30) disposed after the second cooling section (20) based on the measured exit side temperature of the steel strip (5), and controlling a strip winding temperature of steel (5) to fall within a predetermined range.
    [0009]
    9. Method according to any one of claims 1 to 8, characterized in that the second cooling section (20) includes a front cooling section, a middle cooling section, and a rear cooling section, and the method further includes: measuring an outlet side temperature of the steel strip (5) on an outlet side of the front cooling section; and changing a cooling condition in the average cooling section based on the measured exit side temperature of the steel strip (5) in the front cooling section, and controlling temperature of the steel strip (5) in an inlet side of the rear cooling section to fall within a predetermined range.
    类似技术:
    公开号 | 公开日 | 专利标题
    BR112012004729B1|2021-07-20|METHOD FOR COOLING A HOT ROLLED STEEL STRIP
    US20140096578A1|2014-04-10|Method and apparatus for preparing steel stock before hot rolling
    JP5964449B2|2016-08-03|Method and apparatus for controlling strip temperature in quench zone in continuous annealing line
    EP3156512B1|2022-01-12|Method for cooling steel strip and cooling installation
    KR101149210B1|2012-05-29|Cooling control apparatus for hot rolled steel sheets and method thereof
    JP5217509B2|2013-06-19|Manufacturing method and equipment for thick steel plate
    JP4208505B2|2009-01-14|Winding temperature controller
    JP2018144062A|2018-09-20|Winding cooling control device and winding cooling control method
    WO2014087524A1|2014-06-12|Method for cooling hot-rolled steel sheet
    JP4894686B2|2012-03-14|Manufacturing method and manufacturing apparatus for hot-rolled steel sheet
    JP2005169453A|2005-06-30|Method for manufacturing hot-rolled steel strip
    JP5310966B1|2013-10-09|Hot-rolled steel sheet cooling device
    CN103586294B|2016-07-27|The section cooling method of slab, hot continuous rolling production line and laminar cooling system thereof
    CN108472718B|2020-11-20|Secondary cooling method and secondary cooling device for continuous casting blank
    JPH0910812A|1997-01-14|Method for controlling coiling temperature of hot rolled steel sheet
    JP2002172411A|2002-06-18|Method and apparatus for heat-treating thick steel plate
    JP5239887B2|2013-07-17|Hot rolled steel sheet manufacturing apparatus and manufacturing method
    JP5741634B2|2015-07-01|Method and apparatus for cooling control of hot-rolled steel sheet
    KR101089330B1|2011-12-02|Method for Cooling of Hot Steel Strip in Run Out Table and Method for Controlling Cooling the same
    RU2686504C1|2019-04-29|Method for production of rolled strip on wide-band rolling mill
    JP2004042081A|2004-02-12|Method for manufacturing metallic sheet and device for controlling temperature
    TW202146343A|2021-12-16|Methods for manufacturing low liquidus viscosity sheet glass
    JP2019010676A|2019-01-24|Method of manufacturing hot rolled steel sheet
    JP4380183B2|2009-12-09|Steel strip cooling method
    KR20130022863A|2013-03-07|Apparatus for cooling wire-rod coil
    同族专利:
    公开号 | 公开日
    IN2012DN00945A|2015-04-10|
    US20120151981A1|2012-06-21|
    CN102481610B|2014-08-06|
    EP2465620B1|2013-07-03|
    EP2465620A1|2012-06-20|
    US8359894B2|2013-01-29|
    TW201130990A|2011-09-16|
    KR20120038545A|2012-04-23|
    KR101211273B1|2012-12-11|
    EP2465620A4|2012-10-03|
    JPWO2011074632A1|2013-04-25|
    WO2011074632A1|2011-06-23|
    BR112012004729A2|2016-03-15|
    CN102481610A|2012-05-30|
    TWI379010B|2012-12-11|
    JP4938159B2|2012-05-23|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US3604234A|1969-05-16|1971-09-14|Gen Electric|Temperature control system for mill runout table|
    DE2507641A1|1975-02-21|1976-09-02|Sp K Bjuro Uraltschermetwtomat|Hot rolled strip cooling control - varies coolant nozzle group numbers as function of strip velocity and set cooling time|
    JPH01312031A|1988-06-13|1989-12-15|Kawasaki Steel Corp|Manufacture of hot rolled steel stock|
    JPH03198905A|1989-12-26|1991-08-30|Sumitomo Metal Ind Ltd|Control method for cooling rolled stock|
    JPH03277721A|1990-03-28|1991-12-09|Sumitomo Metal Ind Ltd|Method for controlling cooling of hot rolled steel strip|
    JP2744399B2|1993-06-18|1998-04-28|三菱電機株式会社|Rolled material cooling control device|
    JPH08252625A|1995-03-16|1996-10-01|Kawasaki Steel Corp|Method for controlling coiling temperature in hot rolling|
    JP3423500B2|1995-09-19|2003-07-07|三菱電機株式会社|Hot rolled steel sheet winding temperature control apparatus and method|
    JP3058403B2|1996-02-08|2000-07-04|住友金属工業株式会社|Cooling control method for hot rolled steel sheet|
    JP3514914B2|1996-06-20|2004-04-05|三菱電機株式会社|Temperature control method of hot rolled steel sheet|
    JP4164982B2|2000-03-01|2008-10-15|Ｊｆｅスチール株式会社|Hot-rolled steel strip cooling device and cooling method thereof|
    JP3815410B2|2001-08-31|2006-08-30|Ｊｆｅスチール株式会社|Cooling control method for hot-rolled steel strip|
    US7310981B2|2003-02-25|2007-12-25|Siemens Aktiengesellschaft|Method for regulating the temperature of strip metal|
    JP4529517B2|2003-06-27|2010-08-25|Ｊｆｅスチール株式会社|High carbon steel plate manufacturing method and manufacturing equipment|
    JP4525133B2|2004-03-30|2010-08-18|Ｊｆｅスチール株式会社|Manufacturing method of hot-rolled steel strip|
    CN1706568A|2004-06-08|2005-12-14|三菱日立制铁机械株式会社|High strong hot-rolling steel plate producing equipment|
    JP4119928B2|2006-08-18|2008-07-16|新日本製鐵株式会社|Steel plate cooling method|
    JP4238260B2|2006-09-19|2009-03-18|新日本製鐵株式会社|Steel plate cooling method|
    JP4449991B2|2007-02-26|2010-04-14|Ｊｆｅスチール株式会社|Apparatus and method for cooling hot-rolled steel strip|
    JP4894686B2|2007-09-03|2012-03-14|住友金属工業株式会社|Manufacturing method and manufacturing apparatus for hot-rolled steel sheet|
    JP4924579B2|2008-09-08|2012-04-25|Ｊｆｅスチール株式会社|Hot-rolled steel strip cooling device and cooling method thereof|
    US8414716B2|2009-05-13|2013-04-09|Nippon Steel & Sumitomo Metal Corporation|Cooling method of hot-rolled steel strip|FI20070622A|2007-08-17|2009-04-15|Outokumpu Oy|Method and apparatus for controlling uniformity in cooling of a stainless steel strip|
    US9186710B2|2011-06-07|2015-11-17|Nippon Steel & Sumitomo Metal Corporation|Method for cooling hot-rolled steel sheet|
    US9566625B2|2011-06-07|2017-02-14|Nippon Steel & Sumitomo Metal Corporation|Apparatus for cooling hot-rolled steel sheet|
    US9211574B2|2011-07-27|2015-12-15|Nippon Steel & Sumitomo Metal Corporation|Method for manufacturing steel sheet|
    KR101376565B1|2011-12-15|2014-04-02|포스코|Method and apparatus for controlling the temperature of strip in the rapid cooling section of continuous annealing line|
    EP2929949B1|2012-12-06|2018-04-25|Nippon Steel & Sumitomo Metal Corporation|Device for cooling hot-rolled steel sheet|
    JP5741634B2|2013-04-03|2015-07-01|Ｊｆｅスチール株式会社|Method and apparatus for cooling control of hot-rolled steel sheet|
    CN104043660B|2013-09-26|2015-09-30|北大方正集团有限公司|A kind of production technology of non-hardened and tempered steel|
    CN104001742A|2014-05-21|2014-08-27|中冶南方工程技术有限公司|Method for achieving controlled cooling on rolled pieces between and after bar finishing mill units|
    CN106661710B|2014-07-24|2019-04-09|新日铁住金株式会社|The cooling means of steel band and cooling equipment|
    CN104438356B|2014-09-23|2017-04-05|北京首钢股份有限公司|A kind of method for improving Thin container plate edge shape wave|
    CN104668295B|2015-02-13|2017-04-12|中冶南方工程技术有限公司|Control method and control device of rod and wire production line temperature control rolling process|
    EP3061535B1|2015-02-27|2019-02-27|Primetals Technologies Austria GmbH|Reel device with asymmetric cooling of the reeled strip|
    JP6245766B2|2015-05-26|2017-12-13|Ｐｒｉｍｅｔａｌｓ Ｔｅｃｈｎｏｌｏｇｉｅｓ Ｊａｐａｎ株式会社|Hot-rolled steel plate cooling apparatus and mask member position adjusting method|
    WO2021034851A1|2019-08-19|2021-02-25|United States Steel Corporation|High strength steel products and annealing processes for making the same|
    AU2017263399A1|2016-05-10|2019-01-03|United States Steel Corporation|High strength steel products and annealing processes for making the same|
    WO2018029768A1|2016-08-09|2018-02-15|東芝三菱電機産業システム株式会社|Rolling mill exit side temperature control system|
    JP6477919B2|2016-08-22|2019-03-06|Ｊｆｅスチール株式会社|Method for cooling high-temperature metal and method for producing hot-dip galvanized steel strip|
    WO2020227438A1|2019-05-07|2020-11-12|United States Steel Corporation|Methods of producing continuously cast hot rolled high strength steel sheet products|
    WO2021026437A1|2019-08-07|2021-02-11|United States Steel Corporation|High ductility zinc-coated steel sheet products|
    CN110624960B|2019-09-24|2021-02-09|张家港宏昌钢板有限公司|Strip steel cooling control method combining ultra-fast cooling and conventional laminar cooling|
    法律状态:
    2016-11-01| B25D| Requested change of name of applicant approved|Owner name: NIPPON STEEL AND SUMITOMO METAL CORPORATION (JP) |
    2019-01-08| B06F| Objections, documents and/or translations needed after an examination request according [chapter 6.6 patent gazette]|
    2019-08-27| B25D| Requested change of name of applicant approved|Owner name: NIPPON STEEL CORPORATION (JP) |
    2019-10-08| B06U| Preliminary requirement: requests with searches performed by other patent offices: procedure suspended [chapter 6.21 patent gazette]|
    2020-05-12| B06A| Notification to applicant to reply to the report for non-patentability or inadequacy of the application [chapter 6.1 patent gazette]|
    2020-10-13| B06A| Notification to applicant to reply to the report for non-patentability or inadequacy of the application [chapter 6.1 patent gazette]|
    2021-05-18| B09A| Decision: intention to grant [chapter 9.1 patent gazette]|
    2021-07-20| B16A| Patent or certificate of addition of invention granted|Free format text: PRAZO DE VALIDADE: 20 (VINTE) ANOS CONTADOS A PARTIR DE 16/12/2010, OBSERVADAS AS CONDICOES LEGAIS. PATENTE CONCEDIDA CONFORME ADI 5.529/DF, QUE DETERMINA A ALTERACAO DO PRAZO DE CONCESSAO. |
    优先权:
    申请号 | 申请日 | 专利标题
    JP2009-285121|2009-12-16|
    JP2009285121|2009-12-16|
    PCT/JP2010/072639|WO2011074632A1|2009-12-16|2010-12-16|Method for cooling hot-rolled steel plate|
    [返回顶部]