CN112139240A - Production method for reducing performance line difference of reinforcing steel bar - Google Patents
Production method for reducing performance line difference of reinforcing steel bar Download PDFInfo
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- CN112139240A CN112139240A CN202010803077.8A CN202010803077A CN112139240A CN 112139240 A CN112139240 A CN 112139240A CN 202010803077 A CN202010803077 A CN 202010803077A CN 112139240 A CN112139240 A CN 112139240A
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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
- B21B1/16—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 wire rods, bars, merchant bars, rounds wire or material of like small cross-section
- B21B1/18—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 wire rods, bars, merchant bars, rounds wire or material of like small cross-section in a continuous process
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
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Abstract
The invention provides a production method for reducing the performance linear difference of a reinforcing steel bar, which comprises the following steps: step A: controlling the components of the steel bar blank: carbon: 0.18% -0.25%, silicon: 0.20-0.80%, manganese: 1.20-1.60 percent of phosphorus, less than or equal to 0.0045 percent of phosphorus and less than or equal to 0.0045 percent of sulfur; and B: the rolling of the steel bar with the specification of phi 12-phi 20mm adopts a three-slitting or four-slitting process, wherein in the three-slitting or four-slitting process, the hole patterns of a precutting hole K4, a slitting hole K3, a finished product front hole K2 and a finished product hole K1 meet the requirements of design and manufacture: in each hole type, the middle hole is larger than the two side holes by 3 percent of the inner diameter of the hole. The invention reduces the performance fluctuation of each line and improves the performance stability of the reinforcing steel bar.
Description
Technical Field
The invention relates to the field of steel rolling, in particular to a production method for reducing the mechanical property line difference of each line after steel bars are cut, namely a production method for reducing the steel bar property line difference.
Background
In order to improve the yield and the production efficiency of the small-size steel bars and realize energy conservation and consumption reduction, the slitting rolling technology is mostly adopted for the steel bar production. At present, steel bars with the diameter of 25 mm and below in China tend to be produced by adopting a cutting mode of two-cutting, three-cutting, four-cutting and the like according to different specifications, the yield of the steel bars produced by adopting the cutting process can be improved by 10-30%, and correspondingly, the energy consumption can be reduced by 10-20% at the same time, so that the steel bars produced by adopting the cutting process are generally produced by adopting the cutting process in China, especially the steel bars with small specifications.
The size line difference control is one of the difficulties of splitting rolling when the steel bar is produced by adopting a splitting process, the size line difference can cause the size and weight deviation to be over poor and can also cause the performance of the steel bar to fluctuate, the situation generally causes the attention of people and controls the situation in a key way, if Zheng Fu print and the like research the four-splitting size line difference and the control method of the steel bar, the Mongolian analysis solves the splitting process difficulties such as the five-line splitting size line difference of the steel bar with the diameter of 10mm, and the Shao International et al analyzes and controls the 12mm five-splitting performance line difference of the steel bar of Xinjiang Kunyu iron and steel Limited company from the aspects of cooling control, size line difference and the like. At present, the control means for the size line difference of the reinforcing steel bars and the related technology application are relatively mature.
However, in production, even if the reinforcing steel bars with better control of the size line difference of the divided reinforcing steel bars and small size line difference are found, the performance of the reinforcing steel bars, particularly the strength difference of the reinforcing steel bars, still has larger difference, particularly the reinforcing steel bars adopting the three-division and four-division processes.
In summary, the following problems exist in the prior art: under the condition that the size and weight deviation are basically consistent, the performance of the steel bars among the lines is fluctuated, and the mechanical performance line difference of the steel bars is large.
Disclosure of Invention
The invention provides a production method for reducing the performance line difference of a reinforcing steel bar, which aims to solve the problems that the performance of the reinforcing steel bar between each two split lines is fluctuated, and the mechanical performance line difference of each line of the reinforcing steel bar is large.
Therefore, the invention provides a production method for reducing the performance line difference of a reinforcing steel bar, which comprises the following steps:
step A: controlling the components of the steel bar blank: carbon: 0.18% -0.25%, silicon: 0.20-0.80%, manganese: 1.20-1.60 percent of phosphorus, less than or equal to 0.0045 percent of phosphorus and less than or equal to 0.0045 percent of sulfur;
and B: the rolling of the steel bar with the specification of phi 12-phi 20mm adopts a three-slitting or four-slitting process, wherein in the three-slitting or four-slitting process, the hole patterns of a precutting hole K4, a slitting hole K3, a finished product front hole K2 and a finished product hole K1 meet the requirements of design and manufacture:
in each hole type, the middle hole is used for amplifying the inner diameter of the hole according to 3 percent than the two side holes;
and C: heating the billet for rolling the steel bar in the furnace for 60-90 min, adopting three-section heating, controlling the temperature of a soaking section at 1150 +/-40 ℃, controlling the initial rolling temperature at 1040 +/-30 ℃, heating the billet, then rolling the billet by a rough, medium and finish rolling continuous rolling unit, controlling the rolling speed of a finished product rack at 10-15 m/s, and controlling the temperature of an upper cooling bed to be more than or equal to 920 ℃.
Furthermore, the inner diameter of the hole is enlarged by 3% in the middle of the four-split two-line holes compared with the holes at the two sides of the four-split two-line holes, so that the weight deviation of the two-line reinforcing steel bar in the middle of the four-split two-line holes is 2.5-3.5% larger than that of the two-line reinforcing steel bar at the side under the condition of ensuring the normal control of the material type in the rolling process.
Furthermore, the inner diameter of a hole in the middle of the three-segmentation is enlarged by 3% compared with holes on two sides of the three-segmentation, so that the weight deviation of the middle line of the three-segmentation is 2.5-3.5% larger than that of the two-line steel bar on the side surface under the condition of ensuring the normal control of the material type in the rolling process.
Further, in the step a, the carbon: 0.24%, silicon: 0.55%, manganese: 1.34%, phosphorus: 0.023%, sulfur: 0.028 percent.
Further, in the step B, the billet is heated in the furnace for 65min in a three-section heating mode, the temperature of a soaking section is controlled according to 1150 +/-40 ℃, the initial rolling temperature is 1050 ℃, a four-segmentation process and a hole pattern system are adopted, the rolling speed of a finished product rack is controlled at 13m/s, and the temperature of a cooling bed is 960 ℃.
Further, in the step a, the carbon: 0.23%, silicon: 0.46%, manganese: 1.44%, phosphorus: 0.026%, sulfur: 0.027 percent.
Further, in the step B, the billet is heated in the furnace for 62min by adopting three-section heating, the temperature of a soaking section is controlled according to 1150 +/-40 ℃, the initial rolling temperature is 1060 ℃, a three-segmentation process and a pass system are adopted, the rolling speed of a finished product rack is controlled at 13m/s, and the temperature of an upper cooling bed is 980 ℃.
Further, the invention also provides a split steel bar with small performance line difference, and the split steel bar comprises the following components: carbon: 0.18% -0.25%, silicon: 0.20-0.80%, manganese: 1.20-1.60 percent of phosphorus, less than or equal to 0.0045 percent of phosphorus and less than or equal to 0.0045 percent of sulfur;
after cutting, the weight deviation of the steel bars of the middle line is 2.5-3.5% larger than that of the steel bars of the two lines of the side surface.
Furthermore, the segmented steel bars with small performance line difference are four segmented steel bars, and after segmentation, the weight deviation of the steel bars on the two middle lines of the segmented steel bars on the segmented line is 2.5-3.5% larger than that of the steel bars on the two side lines of the segmented steel bars on the side surface.
Furthermore, the segmented steel bars with small performance line difference are three segmented steel bars, and after segmentation, the weight deviation of the steel bars in the middle line on the segmented line is 2.5-3.5% larger than that of the steel bars in the two lines on the side surface.
By means of proper steel bar component control, combined with change of split hole type design, strength of the steel bar is improved by increasing weight deviation, strength reduction caused by steel quality of the steel bar in the middle of three splits and the middle of four splits is compensated, after the technology is adopted, the HRB 400-grade steel bar with the specification of phi 12-phi 20mm and adopting the three-split and four-split processes is adopted, strength difference of the steel bar of each line after being split is reduced to be below 0-15 MPa from 0-25 MPa, performance fluctuation of each split line is greatly reduced, and performance stability of the steel bar is improved.
1. The niobium-added steel bar has four cutting performances:
the yield strength is 420-465 MPa, and the average value is 443 MPa;
same lot performance line difference (yield strength): 0-15 MPa; the average value was 6 MPa.
The niobium-added steel bar has three-cutting performance:
the yield strength is 425-465 MPa, and the average value is 448 MPa;
same lot performance line difference (yield strength): 0-10 MPa; the average value was 4 MPa.
2. The vanadium (nitrogen) added steel bar has four cutting performances:
the yield strength is 420-475 MPa, and the average value is 456 MPa;
same lot performance line difference (yield strength): 0-15 MPa; the average value was 5 MPa.
Three-cutting performance of vanadium (nitrogen) added steel bars:
the yield strength is 420-480 MPa, and the average value is 453 MPa;
same lot performance line difference (yield strength): 0-10 MPa; the average value was 4 MPa.
Drawings
FIG. 1 is a schematic diagram of the hole pattern of a pre-cutting hole K7 used in the present invention;
FIG. 2 is a schematic diagram of the hole pattern of a hole K6 before cutting adopted by the invention;
FIG. 3 is a schematic diagram of the hole pattern of the pre-cutting hole K5 used in the present invention;
FIG. 4 is a schematic diagram of the hole pattern of pre-cut hole K4 used in the present invention;
FIG. 5 is a schematic diagram of the hole pattern of the cutting hole K3 used in the present invention;
FIG. 6 is a schematic diagram of the hole pattern of the front hole K2 for the final product, wherein only one of the cutting holes is shown;
fig. 7 is a schematic diagram of the hole pattern of the finished hole K1 used in the present invention, wherein only one of the plurality of cutting holes is shown.
Detailed Description
In order to more clearly understand the technical features, objects, and effects of the present invention, the present invention will now be described with reference to the accompanying drawings.
The applicant finds that even if the reinforcing steel bars with better control of the size line difference of the reinforcing steel bars and small size line difference are cut, the performance of the reinforcing steel bars, particularly the strength difference of the reinforcing steel bars, still has larger difference, particularly the reinforcing steel bars adopting the three-cutting and four-cutting processes, mainly because: the inevitable defects of central looseness, central segregation and the like in the central area of the cross section of the blank and the coarse crystal area are not evenly distributed to all lines after rolling and splitting, namely, the steel quality of the steel bars of all lines is different, so that the performance of the steel bars is influenced.
The steel bar is generally produced by rolling a continuous casting square billet, the macroscopic structure of the cross section of the square billet is extremely uneven in distribution and generally consists of three parts, namely edge fine equiaxed crystals, middle columnar crystals and core coarse equiaxed crystals; the most common defects of the square billet comprise different grades, inevitable center porosity and center segregation, if the control is not proper, the defects of shrinkage cavity, corner and middle cracks, inclusion, surface pores and the like can also occur, and solute elements such as C, Mn, P, S and the like are generally segregated in the center of the billet. Therefore, the distribution of the structure and defects of the blank itself in the cross section is very uneven, and even in a blank of a normal quality, the steel quality of the central region is greatly different from that of other portions.
The common cutting modes of the steel bars at present mainly comprise three cutting, four cutting and the like of two cutting and multi-line cutting. Taking a four-slit system as an example, as shown in fig. 1, fig. 2, fig. 3, fig. 4, fig. 5, fig. 6 and fig. 7, the four-slit system mainly includes pre-slit holes K5 to K7, pre-slit hole K4, slit hole K3, finished product pre-slit hole K2 and finished product hole K1. As shown in fig. 1, 2 and 3, as can be seen from the four-slit hole system, the holes before slitting are elliptical holes, rectangular holes or box-shaped holes, and compared with the blanks, the rolled pieces before slitting have no obvious change in the structures and defect positions of the blanks, and the centers are loose and are still segregated at the center of the rolled pieces; when the rolled piece passes through the pre-cut hole and the cutting hole, the rolled piece is flattened and cut, when the cutting is finished, the center loose and center segregation band of the blank is mainly distributed to the middle two lines after the cutting, and the side two lines mainly comprise metal flows of fine isometric crystals and middle columnar crystals at the edges of the blank, so that the structures and the defects of the metal flows of the middle two lines and the side two lines after the four-cutting of the rolled piece are obviously different due to the uneven distribution of the structures and the defects of the blank on the cross section. Similarly, for three-segmentation, the steel quality difference between the middle line and the two lines on the side surface is large after the three-segmentation; for the second segmentation, the steel quality of two lines after the segmentation is not very different.
Under the condition that the size deviation and the weight deviation are basically consistent, due to the difference of steel quality between different splitting lines, the strength of the middle line of the three-splitting and the strength of the middle two lines of the four-splitting are both obviously reduced compared with the strength of the two lines on the side surface, by taking HRB400E as an example, the strength of the middle line of the three-splitting and the strength of the middle two lines of the four-splitting are both reduced by 12-16 MPa compared with the yield strength of the two lines on the side surface, the reduction range is 2.5-3.5%, the steel quality of the two lines of the two-splitting is relatively consistent, the yield strength difference is about 5MPa, and the. When the weight deviation of the middle first line of the three-segmentation and the middle two lines of the four-segmentation is relatively small, namely the strength reduction caused by the weight deviation is superposed with the strength reduction caused by steel, the strength reduction value of the steel bars of the middle first line of the three-segmentation and the middle two lines of the four-segmentation can reach 25MPa to the maximum compared with the steel bars of the two lines of the side surface.
Based on the above analysis, the applicant found that: the performance of the steel bars fluctuates due to the inconsistent steel quality among the cutting lines.
Therefore, the invention provides a production method for reducing the performance line difference of a reinforcing steel bar, which comprises the following steps:
step A: controlling the components of the steel bar blank: the components of the segmented reinforcing steel bar are as follows: carbon: 0.18% -0.25%, silicon: 0.20-0.80%, manganese: 1.20-1.60 percent of phosphorus, less than or equal to 0.0045 percent of phosphorus and less than or equal to 0.0045 percent of sulfur;
and B: the rolling of the steel bar with the specification of phi 12-phi 20mm adopts a three-slitting or four-slitting process, wherein in the three-slitting or four-slitting process, the hole patterns of a precutting hole K4, a slitting hole K3, a finished product front hole K2 and a finished product hole K1 meet the requirements of design and manufacture:
in each hole pattern, as shown in fig. 4, 5, 6 and 7, the middle hole enlarges the inner diameter of the hole by 3% compared with the two side holes; under the condition of ensuring that the material type in the rolling process is normally controlled, the weight deviation of the two middle lines of the four-segmentation and the two middle lines of the three-segmentation is 2.5-3.5% greater than that of the two side lines of the steel bars;
and C: heating the billet for rolling the steel bar in the furnace for 60-90 min, adopting three-section heating, controlling the temperature of a soaking section at 1150 +/-40 ℃, controlling the initial rolling temperature at 1040 +/-30 ℃, heating the billet, then rolling the billet by a rough, medium and finish rolling continuous rolling unit, controlling the rolling speed of a finished product rack at 10-15 m/s, and controlling the temperature of an upper cooling bed to be more than or equal to 920 ℃.
Sampling a finished product: 5 samples are cut on different cutting lines of the steel bars, and the sample length is 500-550 mm.
Measuring and calculating the weight deviation of each cut line by the test sample according to the 8.4 requirement in the GB/T1499.2-2018 standard; 1 sample of each cut line is directly subjected to a tensile test according to the GB/T28900 standard without processing.
Further, in step a: controlling the components of the steel bar blank: the components of the segmented reinforcing steel bar are as follows: carbon: 0.18% -0.25%, silicon: 0.20-0.80%, manganese: 1.20-1.60 percent of phosphorus, less than or equal to 0.0045 percent of phosphorus and less than or equal to 0.0045 percent of sulfur; niobium: 0.023% -0.033% or
Carbon: 0.18% -0.25%, silicon: 0.20-0.80%, manganese: 1.20-1.60 percent of phosphorus, less than or equal to 0.0045 percent of phosphorus and less than or equal to 0.0045 percent of sulfur; niobium: 0.023% -0.033% and vanadium: 0.022% -0.034%, nitrogen: 0.0080% -0.0110%;
by controlling components and changing the design of splitting holes, the strength of the steel bar is improved by increasing weight deviation, the strength reduction caused by steel quality of the steel bar in the middle of three-splitting, one line and two lines in the middle of four-splitting is compensated, after the technology is adopted, the HRB 400-grade steel bar with the specification of phi 12-phi 20mm and the three-splitting and four-splitting processes is adopted, the strength difference of the steel bar of each line after splitting is reduced to be below 0-15 MPa from 0-25 MPa, the performance fluctuation of each line after splitting is greatly reduced, and the performance stability of the steel bar is improved.
Furthermore, the inner diameter of the hole is enlarged by 3% in the middle of the four-split two-line holes compared with the holes at the two sides of the four-split two-line holes, so that the weight deviation of the two-line reinforcing steel bar in the middle of the four-split two-line holes is 2.5-3.5% larger than that of the two-line reinforcing steel bar at the side under the condition of ensuring the normal control of the material type in the rolling process.
Furthermore, the inner diameter of a hole in the middle of the three-segmentation is enlarged by 3% compared with holes on two sides of the three-segmentation, so that the weight deviation of the middle line of the three-segmentation is 2.5-3.5% larger than that of the two-line steel bar on the side surface under the condition of ensuring the normal control of the material type in the rolling process.
Example 1
The steel bar with the diameter of 12mm and the HRB400E produced by adopting a four-segmentation process according to the GB/T1499.2-2018 standard is applied, and the concrete steps are as follows:
1) controlling smelting components of the blank: carbon: 0.24%, silicon: 0.55%, manganese: 1.34%, phosphorus: 0.023%, sulfur: 0.028%, niobium: 0.025 percent;
2) the hole patterns of the pre-cut hole K4, the cut hole K3, the finished product front hole K2 and the finished product hole K1 in the rolling procedure are designed and manufactured as follows: the inner diameter of the hole is enlarged by 3 percent compared with the two side holes in the middle of the four-segmentation;
3) heating the billet in the furnace for 65min by adopting three-section heating, controlling the temperature of a soaking section according to 1150 +/-40 ℃, controlling the initial rolling temperature to 1050 ℃, adopting a four-segmentation process and a pass system, controlling the rolling speed of a finished rack to be 13m/s, and controlling the temperature of a cooling bed to be 960 ℃;
4) controlling steel making and rolling according to the process parameters, wherein the weight deviation of the two middle lines of the four-split steel bars is-2.4%, -2.1%, the yield strength is 455MPa and 450MPa, the weight deviation of the two side lines of the four-split steel bars is-5.2%, -5.0%, the yield strength is 445MPa and 450MPa, other tensile property indexes and weight deviation of the steel bars meet the requirements of GB/T1499.2-2018 standard, and the strength fluctuation of the steel bars of all split lines is within 10 MPa.
The niobium-added steel bar has four cutting performances:
the yield strength is 420-465 MPa, and the average value is 443 MPa;
same lot performance line difference (yield strength): 0-15 MPa; the average value was 6 MPa.
The niobium-added steel bar has three-cutting performance:
the yield strength is 425-465 MPa, and the average value is 448 MPa;
same lot performance line difference (yield strength): 0-10 MPa; the average value was 4 MPa.
Example 2
The method is applied to the phi 18mm and HRB400E steel bars produced by the willow steel according to the GB/T1499.2-2018 standard by adopting a three-segmentation process, and comprises the following specific steps:
1) controlling smelting components of the blank: carbon: 0.23%, silicon: 0.46%, manganese: 1.44%, phosphorus: 0.026%, sulfur: 0.027%, vanadium: 0.026%, nitrogen: 0.0088%
2) The hole patterns of the pre-cut hole K4, the cut hole K3, the finished product front hole K2 and the finished product hole K1 in the rolling procedure are designed and manufactured as follows: the inner diameter of the three-cut middle hole is enlarged by 3 percent than that of the two side holes;
3) heating the steel billet in the furnace for 62min by adopting three-section heating, controlling the temperature of a soaking section according to 1150 +/-40 ℃, controlling the initial rolling temperature to 1060 ℃, adopting a three-segmentation process and a pass system, controlling the rolling speed of a finished product rack to be 13m/s, and controlling the temperature of an upper cooling bed to be 980 ℃;
4) controlling steel making and rolling according to the process parameters, wherein the weight deviation of the steel bar at the middle line of the three-segmentation is-1.8%, the yield strength is 455MPa, the weight deviation of the steel bar at the two lines at the side surfaces of the three-segmentation is-4.5%, -4.6%, the yield strength is 455MPa and 460MPa, other tensile property indexes and weight deviations of the steel bar meet the requirements of GB/T1499.2-2018 standard, and the strength fluctuation of the steel bar at each segmentation line is within 5 MPa.
The vanadium (nitrogen) added steel bar has four cutting performances:
the yield strength is 420-475 MPa, and the average value is 456 MPa;
same lot performance line difference (yield strength): 0-15 MPa; the average value was 5 MPa.
Three-cutting performance of vanadium (nitrogen) added steel bars:
the yield strength is 420-480 MPa, and the average value is 453 MPa;
same lot performance line difference (yield strength): 0-10 MPa; the average value was 4 MPa.
Further, the invention also provides a split steel bar with small performance line difference, and the split steel bar comprises the following components: carbon: 0.18% -0.25%, silicon: 0.20-0.80%, manganese: 1.20-1.60 percent of phosphorus, less than or equal to 0.0045 percent of phosphorus and less than or equal to 0.0045 percent of sulfur; niobium: 0.023% -0.033% or
Carbon: 0.18% -0.25%, silicon: 0.20-0.80%, manganese: 1.20-1.60 percent of phosphorus, less than or equal to 0.0045 percent of phosphorus and less than or equal to 0.0045 percent of sulfur; niobium: 0.023% -0.033% and vanadium: 0.022% -0.034%, nitrogen: 0.0080% -0.0110%;
after cutting, the weight deviation of the steel bars of the middle line is 2.5-3.5% larger than that of the steel bars of the two lines of the side surface.
Furthermore, the segmented steel bars with small performance line difference are four segmented steel bars, and after segmentation, the weight deviation of the steel bars on the two middle lines of the segmented steel bars on the segmented line is 2.5-3.5% larger than that of the steel bars on the two side lines of the segmented steel bars on the side surface.
Furthermore, the segmented steel bars with small performance line difference are three segmented steel bars, and after segmentation, the weight deviation of the steel bars in the middle line on the segmented line is 2.5-3.5% larger than that of the steel bars in the two lines on the side surface.
The above description is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention. In order that the components of the present invention may be combined without conflict, it is intended that all equivalent changes and modifications made by those skilled in the art without departing from the spirit and principles of the present invention shall fall within the protection scope of the present invention.
Claims (9)
1. The production method for reducing the performance linear difference of the reinforcing steel bar is characterized by comprising the following steps of:
step A: controlling the components of the steel bar blank: carbon: 0.18% -0.25%, silicon: 0.20-0.80%, manganese: 1.20-1.60 percent of phosphorus, less than or equal to 0.0045 percent of phosphorus and less than or equal to 0.0045 percent of sulfur;
and B: the rolling of the steel bar with the specification of phi 12-phi 20mm adopts a three-slitting or four-slitting process, wherein in the three-slitting or four-slitting process, the pre-cut holes K4 and the slit holes K3 have the hole patterns of a finished product front hole K2 and a finished product hole K1 as follows:
the inner diameter of the middle hole of each hole type is 3 percent larger than that of the holes at the two sides of each hole type;
and C: heating the billet for rolling the steel bar in the furnace for 60-90 min, adopting three-section heating, controlling the temperature of a soaking section at 1150 +/-40 ℃, controlling the initial rolling temperature at 1040 +/-30 ℃, heating the billet, then rolling the billet by a rough, medium and finish rolling continuous rolling unit, controlling the rolling speed of a finished product rack at 10-15 m/s, and controlling the temperature of an upper cooling bed to be more than or equal to 920 ℃.
2. The method for producing a reduced difference in performance line of reinforcing bars according to claim 1, wherein the two middle holes of the four-slit are enlarged by 3% of the inner diameter of the holes than the two side holes of the four-slit, so that the weight deviation of the two middle holes of the four-slit is 2.5-3.5% greater than that of the two side reinforcing bars under the condition of ensuring the normal control of the material type in the rolling process.
3. The method for producing a reduced linear difference of performance of a steel bar according to claim 1, wherein the inner diameter of the three-slit middle hole is 3% larger than that of the three-slit two-side holes, so that the weight deviation of the three-slit middle line is 2.5-3.5% larger than that of the two-side line steel bar under the condition of ensuring the normal control of the material type in the rolling process.
4. The method for producing a steel bar with reduced line difference of performance according to claim 3, wherein in step B, the billet is heated in the furnace for 65min, three-stage heating is adopted, the temperature of the soaking section is controlled according to 1150 +/-40 ℃, the rolling temperature is 1050 ℃, a four-segment splitting process and a pass system are adopted, the rolling speed of the finished stand is controlled at 13m/s, and the temperature of the upper cooling bed is 960 ℃.
5. The method for producing a reduced line difference of performance of a steel bar according to claim 1, wherein in the step a, the ratio of carbon: 0.23%, silicon: 0.46%, manganese: 1.44%, phosphorus: 0.026%, sulfur: 0.027 percent.
6. The method for producing a steel bar with reduced line difference of performance according to claim 5, wherein in step B, the billet is heated in the furnace for 62min, three-stage heating is adopted, the temperature of the soaking section is controlled according to 1150 +/-40 ℃, the initial rolling temperature is 1060 ℃, a three-segment process and a pass system are adopted, the rolling speed of the finished stand is controlled at 13m/s, and the temperature of the upper cooling bed is 980 ℃.
7. The method for producing a steel bar with reduced line difference of performance according to claim 1, wherein in the step a, the steel bar stock further comprises niobium: 0.023% -0.033% or vanadium: 0.022% -0.034%, nitrogen: 0.0080% -0.0110%.
8. The method for producing a reduced line difference of performance of a steel bar according to claim 1, wherein in the step a, the ratio of carbon: 0.24%, silicon: 0.55%, manganese: 1.34%, phosphorus: 0.023%, sulfur: 0.028%, niobium: 0.025 percent.
9. The method for producing a reduced line difference of performance of a steel bar according to claim 1, wherein in the step a, the ratio of carbon: 0.23%, silicon: 0.46%, manganese: 1.44%, phosphorus: 0.026%, sulfur: 0.027%, vanadium: 0.026%, nitrogen: 0.0088%.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112845603A (en) * | 2021-02-01 | 2021-05-28 | 新疆八一钢铁股份有限公司 | Method for reducing phi 14 four-line split thread multiple-length drop |
| CN113600622A (en) * | 2021-07-23 | 2021-11-05 | 首钢水城钢铁（集团）有限责任公司 | Method for controlling dimension of finished product poker obtained by multi-line slitting of bar |
| CN115181904A (en) * | 2021-11-05 | 2022-10-14 | 柳州钢铁股份有限公司 | High-safety hot-rolled steel bar |
Citations (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4357819A (en) * | 1980-06-11 | 1982-11-09 | Structural Metals, Inc. | Method and apparatus for simultaneously forming three uniform metal rounds |
| US4423856A (en) * | 1981-03-18 | 1984-01-03 | Kabushiki Kaisha Kobe Seiko Sho | Controlled cooling apparatus for hot rolled wire rods |
| EP0845307A1 (en) * | 1996-12-02 | 1998-06-03 | Morgan Construction Company | Rolling mill slitting apparatus |
| JP2003205302A (en) * | 2002-01-11 | 2003-07-22 | Kobe Steel Ltd | Method for hot-rolling bar steel and wire rod |
| CN1669686A (en) * | 2005-01-20 | 2005-09-21 | 唐文林 | Process for rolling four-line split ribbed reinforcing steel bar |
| JP2007160316A (en) * | 2005-12-09 | 2007-06-28 | Kobe Steel Ltd | Method for controlling water cooling of rolled material |
| JP2009160628A (en) * | 2008-01-09 | 2009-07-23 | Tama Tlo Ltd | Apparatus for severe plastic deformation and severe plastic deformation method |
| WO2011107848A2 (en) * | 2010-03-02 | 2011-09-09 | Anil Krishna Kar | Improved reinforcing bar and method for manufacturing the same |
| CN102989763A (en) * | 2012-11-26 | 2013-03-27 | 首钢总公司 | Production method of four-segment high-strength aseismic reinforcement |
| CN103071674A (en) * | 2012-12-28 | 2013-05-01 | 天津钢铁集团有限公司 | Four-line segmentation rolling technology of deformed steel bar with diameter of 10mm |
| CN103230940A (en) * | 2013-04-11 | 2013-08-07 | 首钢总公司 | Controlling method for reduction of four-strand slitting line differences and structure property differences |
| CN103464468A (en) * | 2013-08-15 | 2013-12-25 | 甘肃酒钢集团宏兴钢铁股份有限公司 | Method for controlling weight deviation through after-rolling length of hot-rolled steel bar |
| CN103706632A (en) * | 2013-12-20 | 2014-04-09 | 天津钢铁集团有限公司 | Slitting rolling method of 13mm deformed steel bar |
| CN105080972A (en) * | 2015-08-27 | 2015-11-25 | 四川德胜集团钒钛有限公司 | Slit-rolling groove |
| CN204892553U (en) * | 2015-06-29 | 2015-12-23 | 四川省达州钢铁集团有限责任公司 | Slitting pass structure |
| CN109097690A (en) * | 2018-09-14 | 2018-12-28 | 柳州钢铁股份有限公司 | The production method of HRB400 reinforcing bar used for high-speed railway |
| CN109590328A (en) * | 2018-12-11 | 2019-04-09 | 南京钢铁股份有限公司 | A kind of bar segmentation lines difference fast adjustment method |
| CN110280591A (en) * | 2019-06-26 | 2019-09-27 | 安阳钢铁股份有限公司 | A kind of multi wire cutting rolling middle line processing method of bar production controlled rolling process |
| CN111215447A (en) * | 2019-11-20 | 2020-06-02 | 盐城市联鑫钢铁有限公司 | Process method for reducing differential cutting line of multi-section deformed steel bar |
-
2020
- 2020-08-11 CN CN202010803077.8A patent/CN112139240B/en active Active
Patent Citations (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4357819A (en) * | 1980-06-11 | 1982-11-09 | Structural Metals, Inc. | Method and apparatus for simultaneously forming three uniform metal rounds |
| US4423856A (en) * | 1981-03-18 | 1984-01-03 | Kabushiki Kaisha Kobe Seiko Sho | Controlled cooling apparatus for hot rolled wire rods |
| EP0845307A1 (en) * | 1996-12-02 | 1998-06-03 | Morgan Construction Company | Rolling mill slitting apparatus |
| JP2003205302A (en) * | 2002-01-11 | 2003-07-22 | Kobe Steel Ltd | Method for hot-rolling bar steel and wire rod |
| CN1669686A (en) * | 2005-01-20 | 2005-09-21 | 唐文林 | Process for rolling four-line split ribbed reinforcing steel bar |
| JP2007160316A (en) * | 2005-12-09 | 2007-06-28 | Kobe Steel Ltd | Method for controlling water cooling of rolled material |
| JP2009160628A (en) * | 2008-01-09 | 2009-07-23 | Tama Tlo Ltd | Apparatus for severe plastic deformation and severe plastic deformation method |
| WO2011107848A2 (en) * | 2010-03-02 | 2011-09-09 | Anil Krishna Kar | Improved reinforcing bar and method for manufacturing the same |
| CN102989763A (en) * | 2012-11-26 | 2013-03-27 | 首钢总公司 | Production method of four-segment high-strength aseismic reinforcement |
| CN103071674A (en) * | 2012-12-28 | 2013-05-01 | 天津钢铁集团有限公司 | Four-line segmentation rolling technology of deformed steel bar with diameter of 10mm |
| CN103230940A (en) * | 2013-04-11 | 2013-08-07 | 首钢总公司 | Controlling method for reduction of four-strand slitting line differences and structure property differences |
| CN103464468A (en) * | 2013-08-15 | 2013-12-25 | 甘肃酒钢集团宏兴钢铁股份有限公司 | Method for controlling weight deviation through after-rolling length of hot-rolled steel bar |
| CN103706632A (en) * | 2013-12-20 | 2014-04-09 | 天津钢铁集团有限公司 | Slitting rolling method of 13mm deformed steel bar |
| CN204892553U (en) * | 2015-06-29 | 2015-12-23 | 四川省达州钢铁集团有限责任公司 | Slitting pass structure |
| CN105080972A (en) * | 2015-08-27 | 2015-11-25 | 四川德胜集团钒钛有限公司 | Slit-rolling groove |
| CN109097690A (en) * | 2018-09-14 | 2018-12-28 | 柳州钢铁股份有限公司 | The production method of HRB400 reinforcing bar used for high-speed railway |
| CN109590328A (en) * | 2018-12-11 | 2019-04-09 | 南京钢铁股份有限公司 | A kind of bar segmentation lines difference fast adjustment method |
| CN110280591A (en) * | 2019-06-26 | 2019-09-27 | 安阳钢铁股份有限公司 | A kind of multi wire cutting rolling middle line processing method of bar production controlled rolling process |
| CN111215447A (en) * | 2019-11-20 | 2020-06-02 | 盐城市联鑫钢铁有限公司 | Process method for reducing differential cutting line of multi-section deformed steel bar |
Non-Patent Citations (4)
| Title |
|---|
| 张阔斌等: "HRB335热轧带肋钢筋试验分析", 《河北冶金》 * |
| 李芳春等: "《切分轧制》", 31 December 1995, 冶金工业出版社 * |
| 邵际平;陈亚倩;马加波;沈小二;: "影响五线切分棒材性能线差的因素和控制措施" * |
| 金梁: "HRB400E抗震钢筋铌微合金强化机理研究与应用", 《科技创新与应用》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112845603A (en) * | 2021-02-01 | 2021-05-28 | 新疆八一钢铁股份有限公司 | Method for reducing phi 14 four-line split thread multiple-length drop |
| CN113600622A (en) * | 2021-07-23 | 2021-11-05 | 首钢水城钢铁（集团）有限责任公司 | Method for controlling dimension of finished product poker obtained by multi-line slitting of bar |
| CN115181904A (en) * | 2021-11-05 | 2022-10-14 | 柳州钢铁股份有限公司 | High-safety hot-rolled steel bar |
| CN115181904B (en) * | 2021-11-05 | 2023-02-24 | 柳州钢铁股份有限公司 | High-safety hot-rolled steel bar |
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