CN112387790B - Production process of micro-niobium alloyed disc spiral HRB400 and HRB400E - Google Patents
Production process of micro-niobium alloyed disc spiral HRB400 and HRB400E Download PDFInfo
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- CN112387790B CN112387790B CN202011178142.9A CN202011178142A CN112387790B CN 112387790 B CN112387790 B CN 112387790B CN 202011178142 A CN202011178142 A CN 202011178142A CN 112387790 B CN112387790 B CN 112387790B
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- 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
- B21B37/74—Temperature control, e.g. by cooling or heating the rolls or the product
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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
- B21B1/163—Rolling or cold-forming of concrete reinforcement bars or wire ; Rolls therefor
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
- C22C33/06—Making ferrous alloys by melting using master alloys
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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
- C22C38/02—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
- C22C—ALLOYS
- 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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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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Abstract
A production process of micro niobium alloying disc spiral HRB400 and HRB 400E. The micro niobium production disc screws HRB400 and HRB400E comprise the following components in percentage by mass: 0.23 to 0.25 percent of C, less than 0.6 percent of Si, 0.9 to 1.1 percent of Mn0.04 percent of P, less than 0.04 percent of S, 0.005 to 0.01 percent of Nb0.005 and the balance of Fe. The heating furnace is divided into 3 sections for heating, then the finished product of the coiled steel bar is obtained through rough rolling, intermediate rolling and finish rolling, the product is naturally cooled, and the water tank and the fan in the STELMOR controlled cooling line are all closed. The product specification of the HRB400 and HRB400E coiled snails is phi 6-10mm, the yield strength is more than or equal to 420MPa, the tensile strength is more than or equal to 560MPa, the yield ratio is more than or equal to 1.25, the elongation is more than or equal to 16%, the total elongation under maximum force is more than or equal to 9%, and the coiled steel bar finished product has small performance fluctuation and stable and controlled performance.
Description
Technical Field
The invention relates to the technical field of ferrous metallurgy processes, in particular to a production process of micro-niobium alloying disc screws HRB400 and HRB 400E.
Background
The steel bar is mainly used for various large, heavy and light thin-wall and high-rise building structures, and is widely used for civil engineering construction of houses, bridges, roads and the like. The large public facilities such as highways, railways, bridges, culverts, tunnels, flood control, dams and the like and the small public facilities such as foundations, beams, columns, walls, plates and screw steel of house buildings are indispensable structural materials. With the continuous deepening of the urbanization degree of China, the demand of the vigorous development of infrastructure and real estate on the deformed steel is strong.
In recent years, with more intense competition of various steel mills, the main tasks of reducing cost, saving cost, innovating potential and increasing efficiency, improving product benefit and enhancing enterprise competitiveness are promoted, and at present, the following processes are generally adopted for producing HRB400 and HRB400E in the industry:
(1) the first is a production process of microalloying, hot rolling and stelmor air cooling, which is mainly characterized in that alloying elements such as vanadium, niobium, titanium and the like are added, and carbides and nitrides of the alloying elements are precipitated in steel to achieve the effects of grain refinement and precipitation strengthening;
(2) the second is a production process of low-temperature rolling, low-temperature spinning and stelmor air cooling, mainly obtains fine grain tissues through low temperature, but the production process has higher consumption on the power and the abrasion of a rolling mill motor and higher production cost;
(3) the third is a production process of conventional rolling and rapid cooling, the process has high requirements on cooling equipment, the increase of water quantity of a water tank can increase steel piling risks of a rolling mill, and the production rhythm is greatly influenced.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a production process of micro-niobium alloying disc screws HRB400 and HRB400E, and the production process has low cost and high production efficiency.
In order to solve the problems of the prior art, the invention adopts the technical scheme that:
a production process of micro-niobium alloyed disc screws HRB400 and HRB400E comprises the following components in parts by mass: 0.23 to 0.25 percent of C, less than 0.6 percent of Si, 0.9 to 1.1 percent of Mn0.04 percent of P, less than 0.04 percent of S, 0.005 to 0.01 percent of Nb0.005 and the balance of Fe; the production process of the micro-niobium production disc screws HRB400 and HRB400E is specifically implemented according to the following steps: step 1, charging iron ore, coke and limestone from the top of a blast furnace, blowing preheated air into the blast furnace through a peripheral tuyere of the blast furnace, and allowing molten iron produced at high temperature to flow out of an iron notch; step 2, adding the molten iron smelted in the step 1 into a converter, finishing blowing after reaching the end point components and the tapping temperature, adding a silicomanganese alloy in the tapping process, adding the silicomanganese alloy after tapping 1/3 from the converter, and finishing tapping; step 3, blowing argon gas to start refining, adding ferrocolumbium after the argon blowing refining deoxidation is good, wherein the refining time is at least 25 minutes, stopping refining after the smelting components are qualified, and starting casting to obtain a blank when the argon gas is continuously in the whole refining process; step 4, checking the blank, conveying the qualified product to a heating furnace for heating, and dividing the heating treatment into 3 sections, wherein the temperature of the first section of the preheating section is 750-; step 5, carrying out high-pressure water dephosphorization and cooling on the heated steel billet, and then carrying out rough rolling, intermediate rolling and finish rolling in sequence to obtain a finished product of the spiral steel bar, wherein the high-pressure water descaling pressure is controlled to be more than 8Mpa, the start rolling temperature is controlled to be 930-; and 6, coiling and distributing the finished products of the coiled spiral reinforcing steel bars on a STELMOR conveyor after passing through a wire laying machine, and naturally cooling through a STELMOR cooling control line to obtain HRB400 and HRB400E coiled spirals.
The improvement comprises the following components in percentage by mass: 0.24 percent of C, 1.0 percent of Mn1.0 percent, 0.008 percent of Nb and the balance of Fe.
The improvement is that in the step 6, the spinning temperature is 880-920 ℃, the water tank and the fan in the STELMOR controlled cooling line are all closed, and the finished product is naturally cooled.
Has the advantages that:
compared with the prior art, the production process of the micro-niobium alloying disc spiral HRB400 and HRB400E has the following advantages:
(1) only a small amount of niobium is added for microalloying, niobium dissolved in austenite and carbonitride precipitated in rolling respectively play roles in fine grain strengthening and precipitation strengthening, the recrystallization temperature of austenite is increased, grain growth in the austenite process is inhibited, and ferrite grains are finally refined so as to improve the strength and the plasticity of a finished product;
(2) the rolling process intersects conventional HRB400 and HRB400E spiral shell production, the heating temperature is 30-50 ℃ lower than the conventional heating temperature, the initial rolling temperature is 20-30 ℃ lower than the conventional initial rolling temperature, and only silicon-manganese alloy is needed to be added in the tapping process of the step 2, and silicon-iron alloy is not needed to be added;
(3) the cooling control process can obtain fine ferrite and pearlite structures, and achieves the aim of improving the strength and plasticity of finished products;
(4) the HRB400 and HRB400E spiral shell produced by the invention has the product specification of phi 6-10mm, the yield strength of more than or equal to 420MPa, the tensile strength of more than or equal to 560MPa, the yield ratio of more than or equal to 1.25, the elongation of more than or equal to 16 percent, the total elongation of more than or equal to 9 percent under the maximum force, the performance index meeting the national standard requirement, and the performance is stable and controlled.
Detailed Description
A production process of micro-niobium alloyed disc screws HRB400 and HRB400E comprises the following components in parts by mass: 0.23 to 0.25 percent of C, less than 0.6 percent of Si, 0.9 to 1.1 percent of Mn0.04 percent of P, less than 0.04 percent of S, 0.005 to 0.01 percent of Nb0.005 and the balance of Fe.
The production process of the micro-niobium alloying disc screws HRB400 and HRB400E comprises the following specific steps:
step 1, charging iron ore, coke and limestone from the top of a blast furnace, blowing preheated air into the blast furnace through a peripheral tuyere of the blast furnace, and allowing molten iron produced at high temperature to flow out of an iron notch;
step 2, adding the molten iron and the scrap steel smelted in the step 1 into a converter, and after reaching a terminal component and a tapping temperature (the terminal component mainly means that the carbon content in the molten steel is within a target range required by the steel grade to be smelted when the steel is smelted by the converter or an electric furnace), finishing converting, adding a silicon-manganese alloy in the tapping process, adding the silicon-manganese alloy after the steel is tapped 1/3 by the converter, and finishing tapping;
step 3, blowing argon to start refining, adding ferrocolumbium after the argon blowing refining deoxidation is good, wherein the refining time is at least 25 minutes, stopping refining after the smelting components are qualified, and starting casting to obtain a blank when the argon is continuously in the whole refining process;
step 4, checking the blank, conveying qualified products (which mainly comprise chemical components, low-power inspection, size, length, weight, surface quality and the like) to a heating furnace for heating according to the specification of YB/T2011 continuous casting square blank and rectangular blank, and dividing the heating treatment into 3 sections, wherein the temperature of a first section preheating section is 750-800-;
step 5, carrying out high-pressure water dephosphorization and cooling on the heated steel billet, and then sequentially carrying out rough rolling, intermediate rolling and finish rolling to obtain a finished product of the spiral steel bar;
and 6, coiling the finished products of the steel bars of the spiral shell on a STELMOR conveyor after passing through a wire laying machine, and naturally cooling the finished products of the steel bars of the spiral shell through a STELMOR cooling control line to obtain the low-cost HRB400 and HRB400E spiral shells of the spiral shell.
Wherein, the high-pressure water descaling pressure in the step 5 is controlled to be more than 8Mpa, the initial rolling temperature is controlled to be 900-.
In the step 6, the spinning temperature is 880- & lt 920 & gt, the water tank and the fan in the STELMOR controlled cooling line are all closed, and the finished product is naturally cooled.
Setting of chemical components: according to the production characteristics and the process equipment conditions of HRB400 and HRB400E, the chemical composition design is shown in Table 1, the blank is 150 x 1502mm × 16m square billet.
TABLE 1
The metallographic structures of the coiled snails HRB400 and HRB400E produced by the method are ferrite and pearlite, all performance indexes meet the requirements of the national standard hot-rolled ribbed steel bar for reinforced concrete (GB/T1499.2-2018), and the specific contents are shown in Table 2.
TABLE 2
Example 1
The trade mark is as follows: HRB400, specification: Φ 8mm, rolling season: and (5) in summer.
The chemical composition is shown in the following table 3.
TABLE 3
The rolling process comprises the following steps: the blank is heated in a heating furnace into three sections of heating treatment, wherein the temperature of a first section of a preheating section is 750-800 ℃, the temperature of a second section of the heating section is 810-860 ℃, the temperature of a third section of a soaking section is 940-990 ℃, the starting temperature is 900-930 ℃, the temperature of a finish rolling inlet is 860-900 ℃ and the final rolling speed is controlled at 80m/s in the rolling process.
In the temperature control cooling process, the spinning temperature is controlled at 880-920 ℃, the STELMOR cold control line water tank is completely closed, and the fan is completely closed.
The mechanical properties results are given in table 4.
TABLE 4
Example 2
The trade mark is as follows: HRB400E, specification: phi 10mm, rolling season: and (5) in summer.
The chemical composition is shown in the following table 5.
TABLE 5
The rolling process comprises the following steps: heating the blank in a heating furnace is divided into three sections of heating treatment, wherein the temperature of a first section of preheating section is 750-.
In the temperature control cooling process, the spinning temperature is controlled at 880-920 ℃, the STELMOR control cooling line water tank is completely closed, and the fan is completely closed.
The mechanical properties results are given in table 6.
TABLE 6
Example 3
The trade mark is as follows: HRB400E, specification: phi 6mm, rolling season: in winter.
The chemical composition is shown in table 7 below.
TABLE 7
The rolling process comprises the following steps: heating the blank in a heating furnace is divided into three sections of heating treatment, wherein the temperature of a first section of preheating section is 750-.
In the temperature control cooling process, the spinning temperature is controlled at 880-920 ℃, the STELMOR cold control line water tank is completely closed, and the fan is completely closed.
The mechanical properties are given in Table 8.
TABLE 8
Comparative example 1
The trade mark is as follows: HRB400E, specification: Φ 8mm, rolling season: in winter.
The chemical composition is shown in the following table 9.
TABLE 9
The rolling process comprises the following steps: the blank is heated in a heating furnace and is divided into three sections for heating treatment, wherein the temperature of a preheating section at the first section is 800-.
In the temperature-controlled cooling process, the spinning temperature is controlled to be less than or equal to 1030 ℃, 2 water tanks are opened on a STELMOR cooling-controlled line, and 7 fans are opened.
The mechanical properties results are given in Table 10.
Watch 10
The comparison group has the advantages that the yield strength and the tensile strength of part of samples are lower than the requirements of the national standard 'hot rolled ribbed steel bar for reinforced concrete' (GB/T1499.2-2018), and the STELMOR finish rolling water tank and the fan need to be opened, so that the power consumption and the water consumption are increased, the production cost is additionally increased, and the environmental protection requirement of daily benefit tightening is not facilitated.
The above description is only a preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, and any simple modifications or equivalent substitutions of the technical solutions that can be obviously obtained by those skilled in the art within the technical scope of the present invention are within the scope of the present invention.
Claims (3)
1. A production process of micro-niobium alloyed disc screws HRB400 and HRB400E is characterized by comprising the following components in parts by mass: 0.23 to 0.25 percent of C, less than 0.6 percent of Si, 0.9 to 1.1 percent of Mn0.04 percent of P, less than 0.04 percent of S, 0.005 to 0.01 percent of Nb0.005 and the balance of Fe; the production process of the micro-niobium production disc screws HRB400 and HRB400E is specifically implemented according to the following steps: step 1, charging iron ore, coke and limestone from the top of a blast furnace, blowing preheated air into the blast furnace through a peripheral tuyere of the blast furnace, and allowing molten iron produced at high temperature to flow out of an iron notch; step 2, adding the molten iron smelted in the step 1 into a converter, finishing blowing after reaching the end point components and the tapping temperature, adding a silicon-manganese alloy in the tapping process, adding the silicon-manganese alloy after tapping 1/3 in the converter, and finishing tapping; step 3, blowing argon gas to start refining, adding ferrocolumbium after the argon blowing refining deoxidation is good, wherein the refining time is at least 25 minutes, stopping refining after the smelting components are qualified, and starting casting to obtain a blank when the argon gas is continuously in the whole refining process; step 4, checking the blank, conveying the qualified product to a heating furnace for heating, and dividing the heating treatment into 3 sections, wherein the temperature of the first section of the preheating section is 750-; step 5, carrying out high-pressure water dephosphorization and cooling on the heated steel billet, and then carrying out rough rolling, intermediate rolling and finish rolling in sequence to obtain a finished product of the spiral steel bar, wherein the high-pressure water descaling pressure is controlled to be more than 8Mpa, the initial rolling temperature is controlled to be 930-; and step 6, coiling and distributing the finished products of the steel bars of the spiral shell on a STELMOR conveyor after passing through a wire laying head, and naturally cooling through a STELMOR cooling control line to obtain HRB400 and HRB400E spiral shells.
2. The process for producing micro-niobium alloyed disc screws HRB400, HRB400E according to claim 1, comprising the following components in mass fraction: 0.24 percent of C, 1.0 percent of Mn1.0 percent, 0.008 percent of Nb and the balance of Fe.
3. The production process of the micro-niobium alloying disc screws HRB400 and HRB400E as claimed in claim 1, wherein the spinning temperature in step 6 is 880-.
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| CN113373377B (en) * | 2021-05-28 | 2022-10-25 | 广西柳钢华创科技研发有限公司 | Low-cost high-speed bar deformed steel bar with surface oxidized iron sheet thickness of more than 10 mu m and production method thereof |
| CN113943883B (en) * | 2021-09-18 | 2022-07-22 | 广西柳州钢铁集团有限公司 | Method for improving Agt of Nb microalloying HRB400E hot-rolled wire rod steel bar and hot-rolled wire rod steel bar |
| CN115772595A (en) * | 2022-11-17 | 2023-03-10 | 包头钢铁（集团）有限责任公司 | Preparation method of phi 8mm low-cost high-quality high-strength fine-grain hot-rolled wire rod |
| CN116689479B (en) * | 2023-08-08 | 2023-12-26 | 中冶检测认证有限公司 | Technological method for producing vanadium-free low-silicon hot rolled ribbed steel bars |
| CN117144253B (en) * | 2023-09-07 | 2024-04-30 | 中信金属股份有限公司 | Niobium microalloyed hot rolled ribbed steel bar and production method thereof |
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| CN100465321C (en) * | 2005-10-17 | 2009-03-04 | 马鞍山钢铁股份有限公司 | Trace niobium -containing steel for cooling-control reinforced bar and method for producing same |
| CN101077562A (en) * | 2006-05-24 | 2007-11-28 | 首钢总公司 | Method for producing HRB400 reinforcement metal |
| CN101007316A (en) * | 2007-01-24 | 2007-08-01 | 广州钢铁企业集团有限公司 | Method for producing niobium-contained HRB400 grade reinforcing steel |
| CN109355565A (en) * | 2018-11-16 | 2019-02-19 | 通化钢铁股份有限公司 | A kind of Nb-microalloying HRB400E hot rolling anti-seismic steel bar and its production method |
| CN110819892A (en) * | 2019-10-14 | 2020-02-21 | 长沙东鑫环保材料有限责任公司 | Niobium-nitrogen-containing microalloyed HRB400E steel bar and production method thereof |
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