CN111330974A - Hot continuous rolling production method for thick X70 pipeline steel coil - Google Patents
Hot continuous rolling production method for thick X70 pipeline steel coil Download PDFInfo
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- CN111330974A CN111330974A CN202010175751.2A CN202010175751A CN111330974A CN 111330974 A CN111330974 A CN 111330974A CN 202010175751 A CN202010175751 A CN 202010175751A CN 111330974 A CN111330974 A CN 111330974A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B15/00—Arrangements for performing additional metal-working operations specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B15/0007—Cutting or shearing the product
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/004—Heating the product
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0203—Cooling
- B21B45/0209—Cooling devices, e.g. using gaseous coolants
- B21B45/0215—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes
- B21B45/0218—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes for strips, sheets, or plates
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/04—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for de-scaling, e.g. by brushing
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C47/00—Winding-up, coiling or winding-off metal wire, metal band or other flexible metal material characterised by features relevant to metal processing only
- B21C47/34—Feeding or guiding devices not specially adapted to a particular type of apparatus
- B21C47/3433—Feeding or guiding devices not specially adapted to a particular type of apparatus for guiding the leading end of the material, e.g. from or to a coiler
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
- B21B2001/225—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length by hot-rolling
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B15/00—Arrangements for performing additional metal-working operations specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B2015/0057—Coiling the rolled product
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B2261/00—Product parameters
- B21B2261/20—Temperature
Abstract
The invention relates to a hot continuous rolling production method of a thick X70 pipeline steel coil, which comprises a flying shear, 7 finishing mills, a laminar cooling device and a coiling machine, wherein the coiling machine comprises a side guide plate, an upper pinch roll and a lower pinch roll which are arranged closely and a mandrel with a plurality of auxiliary coiling rolls, wherein the side guide plate, the upper pinch roll and the lower pinch roll are arranged in the sequence of the process flow. The rolling quality of the strip steel is improved by adopting a total pressure control and position control mode for a side guide plate of a coiler, adopting a position mode to change the total pressure control mode and then changing the position control mode for a pinch roll, increasing the forward rate of the pinch roll, a core rod and a wrapper roll, establishing the micro-tension at the tail part of the strip steel after steel throwing and the like; the buckle head of the strip steel is prevented from being warped by controlling the finish rolling steel biting rolling force, the height of a rolling line and the difference of the roll diameter; the surface scratch caused by reeling slippage is prevented by rolling the flying shear cutting head and controlling the head not to be cooled. The invention can effectively solve the problem of unstable rolling caused by raised buckle heads, scratches on the surface, poor coil shape and the like of thick pipeline steel, and has good economic and social benefits.
Description
Technical Field
The invention belongs to the technical field of plate rolling and hot rolling, and particularly relates to a hot continuous rolling production method of a thick X70 pipeline steel coil.
Background
The X70 pipeline steel is widely used for the transportation of petroleum and natural gas, and the pipe is generally manufactured by adopting a hot rolled steel coil spiral submerged arc welding mode or a wide and thick plate longitudinal submerged arc welding mode. The X70 pipeline steel coil is big in thickness, high in strength, low in coiling temperature, long in production line and fast in rhythm, has extremely high requirements on the process equipment of a hot rolling production line, and is very difficult to roll efficiently and stably, and the X70 pipeline steel coil is mainly embodied in that:
(1) the thick pipeline steel is continuously and irreversibly rolled by seven finishing mills, so that the problem of warping and buckling is easy to occur, and steel piling is caused when the problem is serious;
(2) laminar cooling adopts rapid cooling to hit a low target coiling temperature, uneven cooling is easy to occur, the shape of the strip steel is not good, and the stability of the side guide plate is affected;
(3) the temperature of the head of the strip steel is too low, so that the head of the strip steel slips in a coiling machine, and the tower shape of the inner ring of the steel coil and the surface of the steel coil are scratched;
(4) the thick pipeline steel is coiled at low temperature, the deformation resistance is large, the pressure of a pinch roll is insufficient, strip steel bows in front of the pinch roll, the roll gap of the pinch roll is lifted, and finally the steel coil is loosened;
(5) after the final finish rolling machine throws steel, the tail part of the strip steel is in a tension losing state, the positions of a coiling side guide plate and a pinch roll and pressure fluctuation are large, and poor coiling problems such as edge staggering, coil loosening and tower shapes are easily caused.
At present, the rolling instability problem caused by the warping buckle head, the surface scratch, the coiling misalignment, the tower shape, the coil loosening and the like of thick pipeline steel seriously affects the rolling efficiency, causes the product quality problem, increases the production cost and needs to be solved urgently.
Disclosure of Invention
The invention provides a hot continuous rolling production method of a thick X70 pipeline steel coil, which is used for solving the problem of unstable rolling caused by thick pipeline steel buckle heads, surface scratches, coiling misalignment, turriform, coil loosening and the like.
The technical scheme adopted by the invention for solving the technical problems is as follows: a hot continuous rolling production method of a thick X70 pipeline steel coil comprises a slab transportation device, a heating furnace, a first phosphorus removal device, an R1 roughing mill, an R2 roughing mill, a flying shear, a second phosphorus removal device, 7 finishing mills, a laminar cooling device and a coiling machine which are arranged according to the process flow sequence of a production line, wherein the coiling machine comprises a side guide plate, an upper pinch roll and a lower pinch roll which are arranged in close proximity and a mandrel with a plurality of coiling-aid rolls, and the method comprises the following steps:
firstly, transporting a starting rolling material transition material into the heating furnace by the casting blank transporting device, and then transporting steel with the temperature lower than 300 ℃ into the heating furnace;
discharging a casting blank, wherein the first phosphorus removal device operates to remove phosphorus from the casting blank for the first time;
step three, feeding the casting blank subjected to primary dephosphorization into the R1 roughing mill, and rolling for one time;
fourthly, the casting blank after being rolled by the R1 roughing mill for one time is fed into the R2 roughing mill for seven times of reciprocating rolling, and the outlet temperature of the R2 roughing mill is controlled to be 980-1020 ℃;
fifthly, cutting the intermediate blank subjected to rough rolling by the flying shear;
sixthly, feeding the cut intermediate blank into the second phosphorus removal device for secondary phosphorus removal;
seventhly, the intermediate blank after secondary dephosphorization is subjected to finish rolling by 7 finish rolling mills in sequence, the first finish rolling mill closes high-pressure water and cooling water and selects to pass through, the second finish rolling mill corrects the rolling force when biting steel, and strip steel is formed at the outlet of the last finish rolling mill after finish rolling by the 3 rd, 4 th, 5 th, 6 th and last finish rolling mills;
step eight, cooling the strip steel by the laminar cooling device;
step nine, the cooled strip steel enters the side guide plate in the coiling machine, passes through the upper pinch roll and the lower pinch roll, and then is coiled on the core rod through a plurality of wrapper rolls;
before the final finish rolling machine throws steel, namely before the final finish rolling machine comes out of the tail end of the strip steel, the side guide plate adopts a total pressure control mode, after the upper pinch roll and the lower pinch roll bite steel and bite the steel, the side guide plate is immediately corrected, the total pressure of the side guide plate is increased by 40% -60%, and after the final finish rolling machine throws the steel, the side guide plate is switched into a position control mode;
before the upper pinch roll and the lower pinch roll bite steel, the upper pinch roll and the lower pinch roll adopt a position control mode, the position control mode is switched to a total pressure control mode after the steel is bitten, and the position control mode is switched to a return position control mode after the last finish rolling machine throws the steel.
Preferably, the heating furnace in the first step is provided with a plurality of heating furnaces, and the number of the initial rolling material transition materials is more than or equal to 10.
Preferably, the temperature difference of the same plate is controlled within 20 ℃ and the temperature difference of different plates is controlled within 10 ℃ when the casting blank is discharged from the furnace in the second step.
Preferably, the first phosphorus removal device in the second step is started when the distance between the casting blank and the phosphorus removal position is more than or equal to 1 second.
Preferably, in the fourth step, when the outlet temperature of the R2 roughing mill is higher than 1020 ℃, phosphorus removal is performed in 1, 3, 5 and 7 passes, and phosphorus removal is performed in 1, 3 and 7 passes when the outlet temperature is lower than 1020 ℃.
Preferably, the length of the flying shear cutting head in the fifth step is more than or equal to 250 mm.
Preferably, the finishing mill in the seventh step comprises an upper working roll and a lower working roll, the height of a rolling line of 7 finishing mills is controlled to be-2-8 mm, and the difference between the roll diameters of the upper working roll and the lower working roll is 0.3-0.5 mm.
Preferably, the laminar flow cooling device in the eighth step adopts an ultra-fast cooling low-pressure mode, the pressure is less than or equal to 0.4MPa, and the non-cooling section of the head of the strip steel is controlled within 3 m.
Preferably, before the steel is coiled and bitten in the ninth step, the advance rate ranges of the upper pinch roll, the lower pinch roll, the mandrel bar and the plurality of wrapper rolls are 13-17%.
Preferably, after the finish rolling machine in the last step throws steel, the total pressure of the pinch rolls is increased to over 100KN, and the torque of the lower pinch roll is reduced to-160% -180%.
Through the technical scheme, compared with the prior art, the invention has the following beneficial effects:
1. the invention can effectively improve the stability of finish rolling and the quality of finish rolling plate shape by controlling the temperature of steel production, increasing the initial rolling transition material, improving the temperature uniformity of the same plate and different plates, ensuring the temperature of the outlet of the rolling and the like.
2. The invention is beneficial to eliminating the buckling head problem of the finish rolling strip steel and improving the finish rolling stability by increasing the steel biting rolling force, controlling the height of the finish rolling line and the diameter difference of the upper working roll and the lower working roll.
3. The flying shear adopts crop rolling and laminar cooling to control the head non-cooling section, and can effectively eliminate the tower shape and surface scratch caused by coiling and slipping due to low head temperature.
4. The laminar cooling of the invention adopts a low-pressure mode, which can effectively improve the plate shape quality after the strip steel is cooled and improve the stability of the coiling side guide plate.
5. According to the side guide plate control mode, the combined mode of total pressure control and position control is adopted, the method can effectively improve the stability of the side guide plate, is beneficial to eliminating misalignment, and improves the coil steel quality of thick pipelines.
6. The method can reduce the left and right play of the tail part of the strip steel, is favorable for eliminating the misalignment and improves the coiling quality of the outer ring of the thick pipeline steel.
7. According to the pinch roll control mode, the position mode is changed into the total pressure control mode and then the position control mode is changed, so that the method can effectively reduce the fluctuation of the pinch roll and is beneficial to eliminating the problem of outer ring unwinding.
Drawings
The invention is further illustrated with reference to the following figures and examples.
FIG. 1 is a diagram of the present invention relating to the location of production equipment;
FIG. 2 is a schematic view of the coiler of the present invention.
In the figure: 10. a slab transport device; 20. heating furnace; 30. a first phosphorus removal device; 40. r1 roughing mill; 50. r2 roughing mill; 60. flying shears; 70. a second phosphorus removal device; 80. a finishing mill; 90. a laminar flow cooling device; 100. a coiler; 110. a side guide plate; 120. an upper pinch roll; 130. a lower pinch roll; 150. a core rod; 160. and (4) a wrapper roller.
Detailed Description
The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic views illustrating only the basic structure of the present invention in a schematic manner, and thus show only the constitution related to the present invention.
At present, the rolling instability problem caused by the warping buckle head, the surface scratch, the coiling misalignment, the tower shape, the coil loosening and the like of thick pipeline steel seriously affects the rolling efficiency, causes the product quality problem, increases the production cost and needs to be solved urgently. In order to solve the problems, the invention provides a hot continuous rolling production method of a thick X70 pipeline steel coil, which is used for solving the problem of unstable rolling caused by buckling, surface scratch, coiling misalignment, turriform, loose coil and the like of the thick pipeline steel coil.
As shown in FIG. 1, the production equipment related to the method comprises a slab conveying device 10, a heating furnace 20, a first phosphorus removal device 30, an R1 roughing mill 40, an R2 roughing mill 50, a flying shear 60, a second phosphorus removal device 70, 7 finishing mills 80, a laminar cooling device 90 and a coiler 100 which are arranged in the process flow sequence of a production line.
As shown in fig. 2, the coiler 100 includes a side guide 110, an upper pinch roll 120 and a lower pinch roll 130, and a mandrel 150 with several wrapper rolls 160. The side guide plate 110 is arranged at the outlet of the laminar cooling device 90, and the strip steel passes through the laminar cooling device 90, is corrected by the side guide plate 110, and then enters the roll gap between the upper pinch roll 120 and the lower pinch roll 130. The strip steel passing through the roll gap between the upper pinch roll 120 and the lower pinch roll 130 passes through a plurality of wrapper rolls 160 and is wound on the mandrel 150.
Example 1
The method comprises the following steps: the slab conveying device 10 conveys initial rolling material transition materials into the heating furnace 20, the heating furnace 20 is provided with a plurality of blocks, the number of the initial rolling material transition materials is more than or equal to 10, and after the initial rolling material transition materials enter the heating furnace 20, slabs (only cooled naturally) with the temperature lower than 300 ℃ are conveyed into the heating furnace 20.
In the first step, the steel charging temperature is controlled below 300 ℃ in order to avoid the generation of hot cracks caused by overhigh thermal stress on the surface of the steel billet. Before the billet steel enters the heating furnace 20, the initial rolling transition materials are loaded, and the number of the initial rolling transition materials is regulated to be more than or equal to 10, so that the purpose is to iron and preheat the rollers, the rollers are in a better state, and the stability of finish rolling during the process of rolling the pipeline steel is improved. And (3) controlling the temperature difference of the same plate within 20 ℃ and the temperature difference of the different plates within 10 ℃ when the casting blank obtained after being heated by the heating furnace 20 is discharged. The same-plate temperature difference refers to the temperature difference of each measuring point on the whole surface of the same steel plate, and the different-plate temperature difference refers to the temperature difference of different steel plates. The temperature difference of the same plate is controlled within 20 ℃, and the temperature difference of the different plate is controlled within 10 ℃ so as to improve the product quality and the rolling stability.
The scheme comprises the following steps: after the casting blank is discharged from the furnace, the first phosphorus removal device 30 operates to remove phosphorus from the casting blank once. The first phosphorus removal device 30 is started when the casting blank reaches the phosphorus removal position for more than or equal to 1 second.
In the second step, if the casting blank reaches the dephosphorization position and then the first dephosphorization device 30 is started, delay occurs, which leads to the dephosphorization leakage at the head of the casting blank. Therefore, the first phosphorus removal device 30 is started when the distance between the casting blank and the phosphorus removal position is more than or equal to 1 second, so as to prevent phosphorus from leaking from the head of the casting blank.
The third step of the scheme is as follows: the casting blank subjected to primary dephosphorization enters the R1 roughing mill 40 and is rolled for one time;
the scheme comprises the following steps: and the steel plate enters the R2 roughing mill 50 for seven times of reciprocating rolling, and the outlet temperature of the R2 roughing mill 50 is controlled to be 980-1020 ℃.
In the third step and the fourth step, the outlet temperature of the R2 roughing mill 50 is controlled to be 980-1020 ℃, because the temperature is in the temperature range, the subsequent finish rolling and final rolling and coiling temperature control are facilitated, and the final performance requirement is met. There may be differences in the R2 roughing mill 50 inlet temperature, and to bring the R2 roughing mill 50 outlet temperature within the target range, the R2 roughing mill 50 outlet temperature may be further fine tuned by a phosphorus removal open pass to reach the target temperature. When the outlet temperature of the R2 roughing mill 50 is higher than 1020 ℃, phosphorus is removed in 1, 3, 5 and 7 passes, and when the outlet temperature of the R2 roughing mill 50 is lower than 1020 ℃, phosphorus is removed in 1, 3 and 7 passes.
The scheme comprises the following five steps: the roughly rolled intermediate billet is rolled by the flying shear 60, and the length of the crop end is more than or equal to 250 mm.
The scheme comprises the following steps: the cut intermediate blank enters the second phosphorus removal device 70 for secondary phosphorus removal.
The scheme comprises the following steps: the intermediate billet after secondary dephosphorization is subjected to finish rolling by 7 finishing mills 80 in sequence, the first finishing mill 80 closes high-pressure water and cooling water and selects to pass through, and when the second finishing mill 80 bites steel, the rolling force is corrected, specifically, two sides of the second finishing mill 80 are synchronously pressed down, and the roll gap is finely adjusted to realize the increase of the rolling force; and after the strip steel is subjected to finish rolling by a finishing mill 80 of the 3 rd, the 4 th, the 5 th, the 6 th and the final stages, strip steel is formed at the outlet of the finishing mill 80 of the final stage.
And seventhly, the finishing mill 80 comprises an upper working roll and a lower working roll, the height of a rolling line of 7 finishing mills 80 is controlled to be-2-8 mm, and the difference between the roll diameters of the upper working roll and the lower working roll is 0.3-0.5 mm. The problem of warping and buckling easily occurs in thick specification rolling, and the height of a rolling line is adjusted through the roll diameter of the lower working roll to control the warping and buckling. And the roll diameter difference of the upper working roll and the lower working roll is that after the roll diameter of the lower working roll is determined, the roll diameter of the upper working roll is determined according to the roll diameter difference, and the warping buckle head is controlled.
The method comprises the following steps: the strip steel is cooled by the laminar cooling device 90; in the eighth step, the laminar cooling device 90 adopts an ultra-fast cooling low-pressure mode, the pressure is less than or equal to 0.4MPa, and the non-cooling section of the head of the strip steel is controlled within 3 m. The low-pressure mode facilitates uniform cooling, and if the temperature of the strip steel head is too low, the strip steel head can slip in the coiler 100, so that the tower shape of the inner ring of the steel coil and the surface of the steel coil are scratched, and the head non-cold section needs to be controlled to eliminate the supercooling of the head temperature.
The method comprises the following nine steps: the cooled strip steel enters the side guide plate 110 in the coiler 100, passes through the upper pinch roll 120 and the lower pinch roll 130, and is coiled on the mandrel 150 through the plurality of wrapper rolls 160. In the ninth step, before steel is coiled, the advance rate of the upper pinch roll 120, the lower pinch roll 130, the mandrel bar 150 and the plurality of wrapper rolls 160 is between 13% and 17%.
When the strip steel is cast by the final finishing mill 80 (i.e. before the final finishing mill 80 is cast at the tail of the strip steel), the side guide plate 110 adopts a total pressure control mode, after the upper pinch roll 120 and the lower pinch roll 130 bite the steel and bite the steel, the side guide plate 110 is corrected immediately, the total pressure of the side guide plate 110 is increased by 40% -60%, and after the final finishing mill 80 casts the steel, the side guide plate 110 is switched to a position control mode. Before the upper pinch roll 120 and the lower pinch roll 130 bite steel, the upper pinch roll 120 and the lower pinch roll 130 adopt a position control mode, the position control mode is switched to a total pressure control mode after biting the steel, and the position control mode is switched back after the finish rolling mill 80 at the last stage throws the steel.
The pressure control mode is such that the pressures on both sides of the side guides 110 are equal to the target pressure. This mode is effective when tension is established in finish rolling and coiling, but after the final finishing mill 80 throws steel, the strip may have poor strip shape, and if the pressure control mode is also used, the roll gap and pressure change of the side guide 110 are large, and poor coiling is easily caused. The control method should adopt an unused control mode when the last finishing mill 80 and the upper and lower pinch rolls have tension and when the last finishing mill 80 throws out tension, and the side guide 110 adopts a total pressure control and position control mode. The method specifically comprises the following steps: before the final finishing mill 80 throws steel, a total pressure control mode is adopted, and after the head of the coiler 100 bites steel, the side guide plate 110 of the coiler 100 is immediately corrected, so that the pressure of the side guide plate 110 is increased. After the final finishing mill 80 throws steel, the position control mode is switched. The side guide plate 110 adopts a total pressure control and position control mode, and the method can reduce the influence of roll gap and pressure fluctuation of the side guide plate 110 on strip steel edge loss and coil shape.
The shapes of the head and the tail of the strip steel are unstable, and the poor shapes of the head and the tail can cause the upper pinch roll and the lower pinch roll to be lifted in a pressure control mode, so that the roll shape is poor, and a position control mode is adopted at the head section and the tail section. The position control mode means that the positions of the upper pinch roll and the lower pinch roll are fixed values, and after the positions are set, the system can automatically adjust according to the set values. And the middle section has a better plate shape, and a total pressure control mode is adopted. By total pressure control mode, it is meant that the total pressure is set to a constant value and the system automatically adjusts according to the set value. According to the scheme, the advance rate is increased, so that the coil is tighter during coiling, and the inner ring is ensured not to be loosened.
After the final finishing mill 80 throws steel, the strip steel running at high speed loses tension, the strip steel is very easy to shift left and right on a roller way, particularly when the strip steel has the problems of wave shape, wedge shape, camber and the like, the shifting is more obvious, and at the moment, the control of the side guide plate 110 is very unstable. The invention adopts the technical scheme that proper tension is established at the tail part of a steel coil, namely after the finishing mill 80 at the last stage throws steel, the pressure of a pinch roll is increased, the torque of a lower pinch roll 130 is reduced, the speed lag coefficient of a laminar flow roller way is adjusted, and the small tension is ensured after finish rolling and throwing steel, and the specific implementation method comprises the following steps: after the final finishing mill 80 throws steel, the pressure of the pinch roll is increased to be more than 100KN, the torque of the lower pinch roll 130 is reduced to-160% -180%, and the speed hysteresis coefficient of the laminar flow roller way is 3% -8%. The method can reduce the left and right play of the tail part of the strip steel, is favorable for eliminating the misalignment, and improves the coiling quality of the thick pipeline steel outer ring.
The following provides a preferred embodiment of the present invention in combination with a specific example of a 15.9mm thick 1500mm wide X70 coiled steel pipeline (wherein 7 finishing mills 80 are numbered F1, F2, F3, F4, F5, F6, and F7 in this order):
(1) the steel loading temperature is below 300 ℃, and surface cracks are avoided. Rolling 15 pieces of transition materials, so that a finish rolling roller is in a better state when the pipeline steel is rolled;
(2) the temperature of the heating furnace 20 is controlled as shown in table 1, the temperature difference between the same plate and the different plate during the discharging of the casting blank is controlled within 20 ℃, and the temperature difference between the different plates is controlled within 10 ℃, so that the rolling stability is improved;
TABLE 1 furnace 20 temperature control
| Preheating section/. degree.C | First heat/. degree.C | Second heating/. degree.C | Soaking section/. degree.C |
| 1160±20 | 1230±20 | 1270±20 | 1250±20 |
(3) The time for phosphorus removal starting of the R1 roughing mill 40 and the R2 roughing mill 50 is advanced by 1 second, so that the phosphorus removal of the head is ensured to be clean. The outlet temperature of the R2 roughing mill 50 is controlled at 980-1020 ℃, when the outlet temperature is higher than 1020 ℃, the phosphorus is removed in 1, 3, 5 and 7 passes, when the outlet temperature is lower than 1020 ℃, the phosphorus is removed in 1, 3 and 7 passes, and the temperature difference of different plates of different heating furnaces 20 after casting blanks enter finish rolling is small;
(4) the cutting head of the flying shear is rolled, the length of the cutting head is 300mm, the irregular shape of the head is eliminated, and the black mark is removed, so that the coiling is convenient;
(5) f1 high-pressure water and roller cooling water are closed and are selected to be empty, and when F2 bites steel, the rolling force is corrected, the rolling force is increased, and head warping is prevented. The increase of the rolling force is realized through fine adjustment of the roll gap, and the method specifically comprises the following steps: pressing down for 0.1mm, namely synchronously pressing down the two sides of F2 to prevent side bending;
(6) the height of the rolling line of each stand and the difference between the roll diameters of the upper working roll and the lower working roll are controlled to prevent the phenomenon of buckle warping, and the method is specifically shown in the following tables 2 and 3.
TABLE 2 height of pass line
| Rack | F1 | F2 | F3 | F4 | F5 | F6 | F7 |
| Height | -2.0～3.0 | -2.0～5.0 | 0.0～5.0 | 0.0～6.0 | 0.0～6.0 | 3.0～7.0 | 5.0～8.0 |
TABLE 3 difference between the roll diameters of the upper and lower working rolls
| Rack | F1 | F2 | F3 | F4 | F5 | F6 | F7 |
| Difference of roller diameter | 0.7～0.8 | 0.4～0.5 | 0.3～0.4 | 0.3～0.4 | 0.3～0.4 | 0.4～0.5 | 0.3～0.4 |
(7) The laminar cooling device 90 adopts an ultra-fast cooling low-pressure mode, the pressure is 0.4MPa, and the plate shape quality after cooling is improved. The head non-cooling section is controlled within 3m, so that the rolling inner ring is prevented from slipping;
(8) the side guide 110 of the coiler 100 adopts a total pressure control and position control mode, which specifically comprises the following steps: before F7 steel throwing, a total pressure control mode is adopted, the target pressure is 60KN, after the head of the coiler 100 bites steel, the side guide 110 of the coiler 100 is immediately corrected, and the pressure of the side guide 110 of the coiler 100 is increased to about 90 KN. F7, switching to a position control mode after steel throwing;
(9) the pinch roll adopts a position mode to change into a total pressure control mode and then to change into a position control mode, and the method specifically comprises the following steps: before coiling the steel biting, the pinch roll adopts a position control mode, the pinch roll is switched into a total pressure mode after the steel biting, and the position control mode is switched back after the steel throwing at the tail part of the strip steel;
(10) before coiling and biting steel, the forward rates of the pinch roll, the core rod 150 and the wrapper roll 160 are increased by 2 percent compared with the conventional steel grade, and are about 15 percent, so that the inner ring is ensured not to be uncoiled.
(11) And F7, after the steel is thrown, the pressure of the pinch roll and the speed of the layer cooling roll way are adjusted to establish proper tension at the tail part of the steel coil. The method specifically comprises the following steps: after F7 steel throwing, the pinch roll pressure is increased by 50KN to reach about 110KN, the torque of the lower pinch roll 130 is reduced to the amplitude limiting range of-180%, the laminar flow roller way speed lag coefficient is adjusted to 6%, the sufficient mandrel 150 tension is ensured after finish rolling steel throwing, and the band steel is prevented from shifting left and right.
It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
The meaning of "and/or" as used herein is intended to include both the individual components or both.
The term "connected" as used herein may mean either a direct connection between components or an indirect connection between components via other components.
In light of the foregoing description of the preferred embodiment of the present invention, many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.
Claims (10)
1. The hot continuous rolling production method of the thick X70 pipeline steel coil comprises a slab conveying device (10), a heating furnace (20), a first phosphorus removal device (30), an R1 roughing mill (40), an R2 roughing mill (50), a flying shear (60), a second phosphorus removal device (70), 7 finishing mills (80), a laminar cooling device (90) and a coiling machine (100) which are arranged in the production line process flow sequence, and is characterized in that: the coiling machine (100) comprises a side guide plate (110), an upper pinch roll (120) and a lower pinch roll (130) which are arranged in an adjacent mode and a core rod (150) provided with a plurality of wrapper rolls (160), wherein the side guide plate (110), the upper pinch roll and the lower pinch roll are arranged in the adjacent mode, and the method comprises the following steps:
firstly, transporting a starting rolling material transition material into the heating furnace (20) by the casting blank transporting device (10), and then transporting steel with the temperature lower than 300 ℃ into the heating furnace (20);
discharging a casting blank, wherein the first phosphorus removal device (30) operates to remove phosphorus from the casting blank for the first time;
step three, the casting blank subjected to primary dephosphorization enters the R1 roughing mill (40) and is rolled for one time;
fourthly, the casting blank after being rolled by the R1 roughing mill (40) for one time enters the R2 roughing mill (50) for seven times of reciprocating rolling, and the outlet temperature of the R2 roughing mill (50) is controlled to be 980-1020 ℃;
fifthly, cutting the head of the intermediate blank after rough rolling by the flying shear (60);
sixthly, feeding the cut intermediate blank into a second phosphorus removal device (70) for secondary phosphorus removal;
seventhly, the intermediate blank after secondary dephosphorization is subjected to finish rolling by 7 finish rolling mills (80), the first finish rolling mill (80) closes high-pressure water and cooling water and selects to pass through, when the second finish rolling mill (80) bites steel, the rolling force is corrected, and after finish rolling by 3 rd, 4 th, 5 th, 6 th and last finish rolling mills (80), strip steel is formed at the outlet of the last finish rolling mill (80);
step eight, cooling the strip steel by the laminar cooling device (90);
step nine, the cooled strip steel enters the side guide plates (110) in the coiling machine (100), passes through the upper pinch roll (120) and the lower pinch roll (130), and then is coiled on the core rod (150) through a plurality of wrapper rolls (160);
before the final finishing mill (80) throws steel, namely before the final finishing mill (80) is discharged from the tail of strip steel, the side guide plates (110) adopt a total pressure control mode, after the upper pinch roll (120) and the lower pinch roll (130) bite steel and bite the steel, the side guide plates (110) are immediately corrected, the total pressure of the side guide plates (110) is increased by 40% -60%, and after the final finishing mill (80) throws the steel, the side guide plates (110) are switched to a position control mode;
before the upper pinch roll (120) and the lower pinch roll (130) bite steel, the upper pinch roll (120) and the lower pinch roll (130) adopt a position control mode, after biting the steel, the position control mode is switched to a total pressure control mode, and after the finishing mill (80) at the last stage throws the steel, the position control mode is switched back.
2. The method for producing the steel coil of thick gauge X70 pipeline steel as claimed in claim 1, wherein the method comprises the following steps: in the step one, the heating furnace (20) is provided with a plurality of heating furnaces, and the number of the initial rolling material transition materials is more than or equal to 10.
3. The method for producing the steel coil of thick gauge X70 pipeline steel as claimed in claim 2, wherein: and in the second step, the temperature difference of the same plate is controlled within 20 ℃ and the temperature difference of different plates is controlled within 10 ℃ when the casting blank is discharged from the furnace.
4. The method for producing the steel coil of thick gauge X70 pipeline steel as claimed in claim 3, wherein: and in the second step, the first dephosphorization device (30) is started when the distance between the casting blank and the dephosphorization position is more than or equal to 1 second.
5. The method for producing the steel coil of thick gauge X70 pipeline steel as claimed in claim 4, wherein the method comprises the following steps: in the fourth step, when the outlet temperature of the R2 roughing mill (50) is higher than 1020 ℃, phosphorus removal is carried out in 1, 3, 5 and 7 passes, and phosphorus removal is carried out in 1, 3 and 7 passes when the outlet temperature is lower than 1020 ℃.
6. The method for producing the steel coil of thick gauge X70 pipeline steel as claimed in claim 4, wherein the method comprises the following steps: and in the fifth step, the length of the cutting head of the flying shear (60) is more than or equal to 250 mm.
7. The method for producing the steel coil of thick gauge X70 pipeline steel as claimed in claim 6, wherein the method comprises the following steps: and step seven, the finishing mill (80) comprises an upper working roll and a lower working roll, the height of a rolling line of 7 finishing mills (80) is controlled to be-2-8 mm, and the difference between the roll diameters of the upper working roll and the lower working roll is 0.3-0.5 mm.
8. The method for producing the steel coil of thick gauge X70 pipeline steel as claimed in claim 7, wherein the method comprises the following steps: and in the step eight, the intermediate laminar flow cooling device (90) adopts an ultra-fast cooling low-pressure mode, the pressure is less than or equal to 0.4MPa, and the non-cooling section of the head of the strip steel is controlled within 3 m.
9. The method for producing the steel coil of thick gauge X70 pipeline steel as claimed in claim 8, wherein: before steel biting in the step nine, the advance rate ranges of the upper pinch roll (120), the lower pinch roll (130), the mandrel (150) and the plurality of wrapper rolls (160) are 13-17%.
10. The method for producing the steel coil of thick gauge X70 pipeline steel as claimed in claim 8, wherein: and after the finishing mill (80) at the last stage in the step nine throws steel, increasing the total pressure of the pinch rolls to be more than 100KN, and reducing the torque of the lower pinch roll (130) to-160% -180%.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112872050A (en) * | 2021-01-12 | 2021-06-01 | 首钢京唐钢铁联合有限责任公司 | Method for preventing head of thin-gauge strip steel from being folded in laminar cooling mode |
| CN112870588A (en) * | 2021-01-13 | 2021-06-01 | 首钢京唐钢铁联合有限责任公司 | Fire extinguishing method and system for coil stripping of coiling machine and electronic terminal |
| CN113263050A (en) * | 2021-04-14 | 2021-08-17 | 首钢集团有限公司 | Method for producing high-surface-quality strip steel |
| CN113877968A (en) * | 2020-07-01 | 2022-01-04 | 宝山钢铁股份有限公司 | Method for preventing width fixing machine from slipping |
| CN114433639A (en) * | 2022-03-14 | 2022-05-06 | 武汉钢铁有限公司 | Production method capable of reducing flying and warping of ultrathin strip steel on CSP production line |
| CN114535355A (en) * | 2022-03-10 | 2022-05-27 | 山东钢铁集团日照有限公司 | Side guide plate control method of hot rolling coiler capable of improving coil quality |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103551421A (en) * | 2013-11-11 | 2014-02-05 | 攀钢集团攀枝花钢钒有限公司 | Coiling method of hot continuous rolling free plate |
| JP2015193022A (en) * | 2014-03-31 | 2015-11-05 | 日新製鋼株式会社 | take-up control method |
| CN110270591A (en) * | 2019-06-11 | 2019-09-24 | 首钢京唐钢铁联合有限责任公司 | Pipe line steel batches control method |
| CN110656228A (en) * | 2019-10-31 | 2020-01-07 | 攀钢集团攀枝花钢铁研究院有限公司 | Production method of thick X80 pipeline steel |
| CN110871221A (en) * | 2018-08-30 | 2020-03-10 | 宝山钢铁股份有限公司 | Method and device for preventing coiler from steel scrap |
-
2020
- 2020-03-13 CN CN202010175751.2A patent/CN111330974B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103551421A (en) * | 2013-11-11 | 2014-02-05 | 攀钢集团攀枝花钢钒有限公司 | Coiling method of hot continuous rolling free plate |
| JP2015193022A (en) * | 2014-03-31 | 2015-11-05 | 日新製鋼株式会社 | take-up control method |
| CN110871221A (en) * | 2018-08-30 | 2020-03-10 | 宝山钢铁股份有限公司 | Method and device for preventing coiler from steel scrap |
| CN110270591A (en) * | 2019-06-11 | 2019-09-24 | 首钢京唐钢铁联合有限责任公司 | Pipe line steel batches control method |
| CN110656228A (en) * | 2019-10-31 | 2020-01-07 | 攀钢集团攀枝花钢铁研究院有限公司 | Production method of thick X80 pipeline steel |
Non-Patent Citations (5)
| Title |
|---|
| 张景进等: "《热连轧带钢生产实训》", 30 June 2014 * |
| 张福明等: "首钢京唐2250mm热轧生产线采用的先进技术", 《轧钢》 * |
| 张英慧等: "装炉方式对X70管线钢组织和性能的影响 ", 《焊管》 * |
| 胡松涛: "太钢2250mm热连轧X80管线钢的生产实践 ", 《中国冶金》 * |
| 贺龙: "唐钢UTSP 1810生产线卷取侧导板自动控制 ", 《数字化用户》 * |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113877968A (en) * | 2020-07-01 | 2022-01-04 | 宝山钢铁股份有限公司 | Method for preventing width fixing machine from slipping |
| CN113877968B (en) * | 2020-07-01 | 2023-12-12 | 宝山钢铁股份有限公司 | Method for preventing slipping of width-fixing machine |
| CN112872050A (en) * | 2021-01-12 | 2021-06-01 | 首钢京唐钢铁联合有限责任公司 | Method for preventing head of thin-gauge strip steel from being folded in laminar cooling mode |
| CN112870588A (en) * | 2021-01-13 | 2021-06-01 | 首钢京唐钢铁联合有限责任公司 | Fire extinguishing method and system for coil stripping of coiling machine and electronic terminal |
| CN113263050A (en) * | 2021-04-14 | 2021-08-17 | 首钢集团有限公司 | Method for producing high-surface-quality strip steel |
| CN114535355A (en) * | 2022-03-10 | 2022-05-27 | 山东钢铁集团日照有限公司 | Side guide plate control method of hot rolling coiler capable of improving coil quality |
| CN114535355B (en) * | 2022-03-10 | 2023-10-31 | 山东钢铁集团日照有限公司 | Control method of side guide plate of hot rolling coiling machine capable of improving coil quality |
| CN114433639A (en) * | 2022-03-14 | 2022-05-06 | 武汉钢铁有限公司 | Production method capable of reducing flying and warping of ultrathin strip steel on CSP production line |
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