CN111729939A - Method for reducing impact of heavy and medium plate mill head - Google Patents
Method for reducing impact of heavy and medium plate mill head Download PDFInfo
- Publication number
- CN111729939A CN111729939A CN202010410611.9A CN202010410611A CN111729939A CN 111729939 A CN111729939 A CN 111729939A CN 202010410611 A CN202010410611 A CN 202010410611A CN 111729939 A CN111729939 A CN 111729939A
- Authority
- CN
- China
- Prior art keywords
- rolling
- pass
- reduction
- thickness
- head
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 24
- 238000005096 rolling process Methods 0.000 claims abstract description 90
- 230000009467 reduction Effects 0.000 claims abstract description 49
- 229910000831 Steel Inorganic materials 0.000 description 21
- 239000010959 steel Substances 0.000 description 21
- 238000010586 diagram Methods 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- 230000008901 benefit Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000008719 thickening Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000029087 digestion Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000000844 transformation Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/16—Control of thickness, width, diameter or other transverse dimensions
- B21B37/24—Automatic variation of thickness according to a predetermined programme
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/48—Tension control; Compression control
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B2271/00—Mill stand parameters
- B21B2271/02—Roll gap, screw-down position, draft position
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Metal Rolling (AREA)
- Control Of Metal Rolling (AREA)
Abstract
The invention discloses a method for reducing head impact of a heavy and medium plate mill, which is used for rolling with variable thickness by taking two passes as a group and specifically comprises the following steps: (1) controlling the rolling reduction to be engaged in the first pass, starting loaded rolling reduction after rolling is stable, gradually increasing the rolling reduction, and performing variable-thickness rolling, wherein the longitudinal thickness of the rolled piece is in a head-thick-tail thin shape after the rolling of the pass is finished; (2) then, carrying out a second pass, gripping the tail part of the rolled piece with relatively thin thickness of the previous pass, and carrying out variable thickness rolling in a mode of gradually increasing the reduction, wherein after the rolling of the second pass is finished, the longitudinal head and tail thicknesses of the rolled piece are consistent; the method realizes the variable thickness rolling of the thick plate, ensures the stability of equipment, improves the quality of thick plate products, reduces rolling passes and improves the rolling yield.
Description
Technical Field
The invention relates to a method for reducing head impact of a heavy and medium plate mill, in particular to a method for improving pass reduction in the rolling process of a heavy and medium plate steel plate.
Background
In recent years, a plurality of wide and thick plate rolling mill production lines are newly built in China, and the technical level of wide and thick plate production and the product quality are greatly improved. Under the increasingly intense market competition environment, various wide and thick plate factories actively aim at further improving the technical level, producing products with high added values, such as development and production of extra-thick plates, longitudinal variable-thickness plates LP (Linear pressure) plates, extremely-thin gauge plates and the like, improving the product rectangularity and improving the yield.
The production of the extra-thick plate needs to overcome the problems of loose internal structure, coarse grains, segregation and the like of the blank. And the method is an important method for improving the inherent quality of the extra-thick plate product by increasing the pass reduction and promoting the deformation to penetrate into the center of the blank. The pass reduction is limited by conditions such as biting, rolling force, rolling torque, current impact and the like depending on conditions of rolling mill equipment, and particularly, a peak value of the rolling torque caused by head biting impact at the initial stage of a thick billet is an important factor affecting the pass reduction. Therefore, it is considered that the influence of head impact is reduced by a variable thickness rolling method under load reduction, and the pass reduction is increased. According to the invention, through research, development and application of the heavy plate mill loaded pressing technology, the thick plate is rolled in variable thickness, the stability of equipment is ensured, and the quality of a thick plate product is improved.
Disclosure of Invention
The technical problem to be solved by the invention is to overcome the defects of the prior art and provide the method for reducing the head impact of the heavy and medium plate mill.
In order to solve the technical problem, the invention provides a method for reducing the head impact of a heavy and medium plate mill, which performs variable-thickness rolling by taking two passes as a group and specifically comprises the following steps:
(1) controlling the rolling reduction to be engaged in the first time, starting loaded rolling reduction after rolling is stable, and gradually increasing the rolling reduction to perform variable-thickness rolling;
(2) and then, carrying out a second pass, gripping the tail part of the rolled piece with relatively thin thickness of the previous pass, and carrying out variable thickness rolling in a mode of gradually increasing the reduction, wherein after the pass is finished, the longitudinal head and tail thicknesses of the rolled piece are consistent.
The technical scheme of the invention is further defined as follows:
in the method for reducing the head impact of the heavy and medium plate mill, the reduction in thickness of the rolled piece in the first pass and the second pass is small in the head reduction amount and large in the tail reduction amount.
The two passes of the thickness-variable rolling are small in head rolling reduction and then gradually increased, so that the biting limitation during thick billet rolling can be overcome, the influence of moment peak caused by head impact is reduced, and the single-pass rolling reduction is improved.
In the method for reducing the head impact of the heavy and medium plate mill, the reduction of the first pass in the step (1) is 20-25 mm.
In the method for reducing the head impact of the heavy and medium plate mill, the longitudinal thickness of the rolled piece is in a head-thick tail-thin shape after the first-time variable-thickness rolling in the step (1).
In the method for reducing the head impact of the heavy and medium plate mill, after the rolling is stable in the step (1), the loaded reduction is started, and the reduction increase is not more than 10 mm.
The invention has the beneficial effects that:
according to the invention, through research, development and application of the heavy plate mill loaded reduction technology, on the premise of meeting the requirements of the properties of a heavy plate and a steel plate, the heavy plate is rolled in variable thickness, the quality of a heavy plate product is improved, and meanwhile, the variable thickness rolling method is utilized, the pass reduction is improved, effective rolling passes are reduced, the output of the mill is improved, the head impact is reduced, the stability of equipment is improved, the equipment faults are reduced, and the service lives of a main transmission motor and a roller are prolonged.
(1) The heavy plate rolling mill has the variable thickness rolling function aiming at the heavy plate production, and lays a good foundation for the improvement of the quality of the extra-thick plate product. The invention can improve the quality of medium plate products, enrich the product varieties, improve the technical level and the competitiveness of enterprises and have good social benefits.
(2) The invention can reduce the rolling pass number of rolled pieces by two, the average rolling time of each pass is 10s, 5000 pieces of rolled steel plates are produced per month, the production time of each steel plate is 300s, and the number of the rolled steel plates can be increased to 5000 by 10 by 2/300 to 333. Each steel plate is calculated according to the steel benefit of 16 tons and ton by 500 yuan.
The annual benefit is 333 x 16 x 500 x 12 x 3200 ten thousand yuan.
(3) Meanwhile, the use effects of the main transmission and the main motor of the rolling mill are effectively improved.
Drawings
FIG. 1 is a schematic representation of a first pass of the variable thickness rolling in an embodiment of the present invention;
FIG. 2 is a schematic representation of a second pass of the variable thickness rolling in an embodiment of the present invention;
FIG. 3 is a control effect diagram of an automatic system for controlling variable thickness rolling passes of the planar shape of a medium plate;
FIG. 4 is a microstructure diagram at the surface position of a conventionally rolled steel sheet;
FIG. 5 is a microstructure view of a conventional rolled steel sheet at 1/4 of its thickness;
FIG. 6 is a microstructure view of a conventional rolled steel sheet at 1/2 of its thickness;
FIG. 7 is a microstructure diagram of a surface of a rolled steel sheet in accordance with an embodiment of the present invention;
FIG. 8 is a microstructure view of a rolled steel sheet of an embodiment of the present invention taken at a 1/4 thickness portion;
FIG. 9 is a microstructure view of the embodiment of the present invention taken at 1/2 of the thickness of a rolled steel sheet.
Detailed Description
Example 1
The method for reducing the impact of the head of the heavy and medium plate mill provided by the embodiment is used for performing variable-thickness rolling by taking two passes as a group, and specifically comprises the following steps:
(1) as shown in fig. 1 (the head rolling reduction is smaller than the tail rolling reduction), the first step controls the rolling reduction to be 20-25mm, after rolling is stable, the belt load rolling is started, the rolling reduction is gradually increased, the variation amplitude is changed according to different performance characteristics of HGC, the increase amount is 6mm, the variable thickness rolling is carried out, and the longitudinal thickness of the rolled piece is in a head-thick tail-thin shape after the rolling of the current step is finished;
(2) and then, performing a second pass as shown in fig. 2 (at this time, the roll gap is kept unchanged, the reduction is gradually increased in the gripping process, and the rolled steel plate is ensured to be flat after rolling), gripping the tail part of the rolled piece with relatively thin thickness in the previous pass, and performing variable-thickness rolling in a manner that the reduction is gradually increased, wherein after the rolling of the pass is completed, the longitudinal head and tail thicknesses of the rolled piece are consistent.
TABLE 1 shows the rolling parameters of the medium plate
In table 1, variable roll gap rolling is performed from 2 to 9 passes, and the wedge amount indicates the actual thickness of the head part and the tail part which are different in the same pass, and the variation of the head-tail thickness. In this embodiment, the first pass and the second pass of the variable thickness rolling are respectively in a way that the head reduction of the rolled piece is small, the tail reduction is large, and the head reduction is firstly reduced and then increased, and the variable thickness rolling of the two passes is small in the head reduction and then gradually increased, so that the bite limitation during thick blank rolling can be overcome, the influence of the moment peak caused by head impact is reduced, and the single pass reduction is increased.
In this embodiment, in the rolling process of the extra-thick plate, multiple sets of variable thickness rolling can be set by combining two passes into one set.
The invention combines the theoretical research of the variable thickness rolling technology and the digestion work of a field automatic control system, realizes the setting and control model of the variable thickness rolling in the field control system, increases the automatic setting function of wedge rolling passes by modifying a secondary system, realizes the automatic setting of parameters such as wedge degree, rolling reduction, head and tail roll gaps of the wedge rolling passes, and the like, and the high-precision forecast of parameters such as rolling moment, rolling force, forward slip value and the like, checks the wedge degree range under the maximum torque condition of equipment, and prevents the overload phenomenon of a main transmission motor.
The above functions are realized by paying attention to the following points:
(1) the limited value of the rolling moment is limited to be twice of the rated torque according to the capacity of the rolling mill and the set torque of a secondary regulation. That is, the torque calculated according to the maximum rolling reduction of the second pass of the forward rolling reduction for the application of the thickening function is not more than twice of the rated torque, and the torque calculated according to the maximum rolling reduction of the current pass of the application is not more than twice of the rated torque.
(2) The application of the thickening function cannot be realized in the ppo application pass.
(3) The application pass needs to meet the condition that the pass thickness is more than 60mm, and the calculated torque distortion caused by the overlarge temperature drop of the head and the tail of the steel plate is prevented.
According to the invention, the roll gap is dynamically changed in the plane shape control pass, the head and the tail of the rolled piece are thickened, the irregular shapes of the head and the tail of the finished steel plate are compensated by using the thickened volume, and the control effect of the automatic system for the plane shape control variable-thickness rolling pass of the thick plate in the embodiment of figure 3 shows that the rolling force is gradually increased along with the increase of the rolling reduction from the head to the tail.
Table 2: tensile Properties of test steels
As shown in Table 2 and the microstructure test results in FIGS. 7 to 9, the variable thickness rolling has positive significance in improving the deformation uniformity and the metallographic structure in the thickness direction of the medium plate, increasing the impact at the center of the steel plate and the tensile strength at yield, and the grain refinement of FIG. 7 is compared with the microstructure diagram at the surface of the conventional rolled steel plate of FIG. 4, the grain refinement of FIG. 8 is compared with the microstructure diagram at the thickness of 1/4 of the conventional rolled steel plate of FIG. 5, and the grain refinement of FIG. 9 is compared with the microstructure diagram at the thickness of 1/2 of the conventional rolled steel plate of FIG. 6. In addition to the above embodiments, the present invention may have other embodiments. All technical solutions formed by adopting equivalent substitutions or equivalent transformations fall within the protection scope of the claims of the present invention.
Claims (5)
1. The method for reducing the head impact of the heavy and medium plate mill is characterized in that the method for rolling the thickened plate mill by taking two passes as a group comprises the following steps:
(1) controlling the rolling reduction to be engaged in the first time, starting loaded rolling reduction after rolling is stable, and gradually increasing the rolling reduction to perform variable-thickness rolling;
(2) and then, carrying out a second pass, gripping the tail part of the rolled piece with relatively thin thickness of the previous pass, and carrying out variable thickness rolling in a mode of gradually increasing the reduction, wherein after the pass is finished, the longitudinal head and tail thicknesses of the rolled piece are consistent.
2. The method of reducing slamming mill head impact of claim 1, wherein: the thickness-variable rolling of the first pass and the second pass respectively comprises small head rolling reduction and large tail rolling reduction of the rolled piece.
3. The method of reducing slamming mill head impact of claim 1, wherein: the rolling reduction of the first pass in the step (1) is 20-25 mm.
4. The method of reducing slamming mill head impact of claim 1, wherein: and (2) after the first time of variable-thickness rolling in the step (1), the longitudinal thickness of the rolled piece is in a head-thick-tail-thin shape.
5. The method of reducing slamming mill head impact of claim 1, wherein: and (2) starting the loaded reduction after the rolling is stable in the step (1), wherein the increase of the reduction is not more than 10 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010410611.9A CN111729939A (en) | 2020-05-15 | 2020-05-15 | Method for reducing impact of heavy and medium plate mill head |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010410611.9A CN111729939A (en) | 2020-05-15 | 2020-05-15 | Method for reducing impact of heavy and medium plate mill head |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111729939A true CN111729939A (en) | 2020-10-02 |
Family
ID=72647292
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010410611.9A Pending CN111729939A (en) | 2020-05-15 | 2020-05-15 | Method for reducing impact of heavy and medium plate mill head |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111729939A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113042526A (en) * | 2021-03-05 | 2021-06-29 | 邯郸钢铁集团有限责任公司 | Differential thickness rolling method for medium plate |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004283840A (en) * | 2003-03-19 | 2004-10-14 | Jfe Steel Kk | Method for controlling plane shape in thick plate rolling |
| CN101069896A (en) * | 2007-06-15 | 2007-11-14 | 鞍钢股份有限公司 | Medium plate shape control method |
| CN104148384A (en) * | 2014-08-21 | 2014-11-19 | 柳州钢铁股份有限公司 | Rolling technology method for ultra-thin ultra-wide steel plate |
| CN104772338A (en) * | 2014-01-13 | 2015-07-15 | 宝山钢铁股份有限公司 | Method for controlling shape of thick plate rolling plane |
| CN105436210A (en) * | 2015-12-11 | 2016-03-30 | 东北大学 | Thickness-changeable rolling method for heavy and medium plate mill |
-
2020
- 2020-05-15 CN CN202010410611.9A patent/CN111729939A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004283840A (en) * | 2003-03-19 | 2004-10-14 | Jfe Steel Kk | Method for controlling plane shape in thick plate rolling |
| CN101069896A (en) * | 2007-06-15 | 2007-11-14 | 鞍钢股份有限公司 | Medium plate shape control method |
| CN104772338A (en) * | 2014-01-13 | 2015-07-15 | 宝山钢铁股份有限公司 | Method for controlling shape of thick plate rolling plane |
| CN104148384A (en) * | 2014-08-21 | 2014-11-19 | 柳州钢铁股份有限公司 | Rolling technology method for ultra-thin ultra-wide steel plate |
| CN105436210A (en) * | 2015-12-11 | 2016-03-30 | 东北大学 | Thickness-changeable rolling method for heavy and medium plate mill |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113042526A (en) * | 2021-03-05 | 2021-06-29 | 邯郸钢铁集团有限责任公司 | Differential thickness rolling method for medium plate |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108315606B (en) | 1100 alloy aluminum foil for lithium battery and manufacturing method thereof | |
| CN106391708B (en) | Rolling method for producing ultrathin strip steel by using cold rolling six-roller single-stand reversible rolling mill | |
| CN111097798A (en) | Stable production method of hot-rolled thin-specification ultrahigh-strength quenched ductile steel | |
| CN1857809A (en) | Dynamic thickening rolling process of controlling break of cold rolled thin strip steel | |
| CN106825062A (en) | It is a kind of to prevent hot-continuous-rolling strip steel from batching the method for drawing steel | |
| CN106140813A (en) | The cold rolling production method of chrome ferritic stainless steel in a kind of automobile exhaust system | |
| CN111729939A (en) | Method for reducing impact of heavy and medium plate mill head | |
| KR20120074039A (en) | Forging method of heavy thick plate | |
| CN113145642B (en) | Pickling plate and preparation method thereof | |
| CN108994079A (en) | A method of improving magnesium alloy plate and belt roll forming | |
| CN110355213A (en) | Short route production medium carbon steel 50Mn2V's batches staggered floor control method | |
| CN1974046A (en) | Electrical steel producing process | |
| CN111534729B (en) | Method for controlling transverse unevenness of high-strength aluminum alloy plate | |
| CN110385339B (en) | Leveling method of semi-process steel | |
| CN112676341A (en) | Hot rolling method of low-carbon steel | |
| CN113699340A (en) | Method for eliminating yield platform of continuous annealing of thin low-carbon steel of 0.3-0.9mm | |
| CN113042526A (en) | Differential thickness rolling method for medium plate | |
| CN101754824A (en) | Method for production of extrusion billet, and method for production of magnesium alloy material | |
| CN112474800A (en) | Method for producing narrow thickness tolerance X12Ni5 steel by single-stand steckel mill | |
| CN112536405A (en) | Free forging method of large flat square forging | |
| CN114472509B (en) | Rolling method of wedge-shaped blank | |
| CN113680816B (en) | Plain carbon steel wire rod for wire drawing | |
| CN113894175B (en) | Processing method of aluminum plate base for printing | |
| CN115625211B (en) | Plate shape control method of ultrathin galvanized aluminum magnesium cold-rolled substrate | |
| CN118122772A (en) | Method for producing thin plate in 1+N mode |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201002 |
|
| RJ01 | Rejection of invention patent application after publication |