阅读说明：本技术 一种提高连铸坯成材超厚钢板探伤合格率的生产方法 (Production method for improving flaw detection qualification rate of continuous casting billet finished super-thick steel plate ) 是由 邓建军 赵国昌 王甜甜 龙杰 庞辉勇 李劲峰 瞿征 刘彦强 薛帅斌 尹卫江 张剑 于 2019-10-25 设计创作，主要内容包括：本发明公开了一种提高连铸坯成材超厚钢板探伤合格率的生产方法,包括以下步骤：1)精炼完毕Al≥0.010%,S≤0.010%,精炼周期40～50min,精炼座包12～20min,一次喂铝0.8～1.2㎏/t钢脱氧,真空过程真空度60～66Pa,真空保持时间15～25min；2)浇铸前钢水过热度控制在10～30℃,连铸开启电子搅拌；3)钢坯在1200～1260℃高温段炉膛时间为7～9min/cm,总在炉加热时间10～13min/cm；4)控制单道次压下率12～15%；5)堆垛温度400～450℃,堆垛时间24～28h。本发明方法减少了钢板废品率,降低了生产成本,取得良好的经济效益,值得推广使用。(The invention discloses a production method for improving the flaw detection qualification rate of a continuous casting billet finished super-thick steel plate, which comprises the following steps of: 1) after refining, Al is more than or equal to 0.010 percent, S is less than or equal to 0.010 percent, the refining period is 40-50 min, a refining ladle is fed for 12-20 min, 0.8-1.2 kg of aluminum is fed for one time for deoxidation per t of steel, the vacuum degree in the vacuum process is 60-66 Pa, and the vacuum maintaining time is 15-25 min; 2) controlling the superheat degree of molten steel before casting to be 10-30 ℃, and starting electronic stirring in continuous casting; 3) the time of a furnace hearth of the billet at a high temperature of 1200-1260 ℃ is 7-9 min/cm, and the total heating time in the furnace is 10-13 min/cm; 4) controlling the single-pass reduction rate to be 12-15%; 5) the stacking temperature is 400-450 ℃, and the stacking time is 24-28 h. The method reduces the rejection rate of the steel plate, reduces the production cost, obtains good economic benefit and is worthy of popularization and application.)

1. The production method for improving the flaw detection qualification rate of the continuously cast blank finished super-thick steel plate is characterized by comprising the following steps of:

(1) a steel making process: after refining, Al is more than or equal to 0.010 percent, S is less than or equal to 0.010 percent, the refining period is controlled to be 40-50 min, the refining saddlebag is fed for 12-20 min, 0.8-1.2 kg of aluminum is fed once per t of steel for deoxidation, the vacuum degree is kept at 60-66 Pa in the vacuum process, and the vacuum keeping time is 15-25 min;

(2) a casting process: controlling the superheat degree of molten steel before casting to be 10-30 ℃, starting electronic stirring in continuous casting, wherein the electromagnetic stirring frequency is 3-5 Hz, and the electric stirring current is 400-500A, so as to prepare a continuous casting billet;

(3) a heating procedure: the time of a furnace hearth of the billet at a high temperature of 1200-1260 ℃ is 7-9 min/cm, and the total heating time in the furnace is 10-13 min/cm;

(4) a steel rolling procedure: controlling the single-pass reduction rate to be 12-15% by adopting a single-pass large-reduction rolling mode;

(5) slow cooling process: and (3) stacking the rolled steel plates in time at the stacking temperature of 400-450 ℃ for 24-28 h, and unstacking the steel plates for flaw detection.

2. The production method for improving the flaw detection qualification rate of the continuously cast bloom super-thick steel plate as claimed in claim 1, wherein the thickness of the steel plate obtained by the production method is 180-250 mm.

3. The production method for improving the flaw detection qualification rate of the continuously cast blank super-thick steel plate as claimed in claim 1, wherein the flaw detection qualification rate of the steel plate obtained by the production method is 98-100% after flaw detection.

4. The production method for improving the flaw detection qualification rate of the continuously cast bloom super-thick steel plate according to any one of claims 1 to 3, characterized in that the properties of the obtained steel plate are as follows: the yield strength Rel is more than or equal to 370MPa, the tensile strength Rm is more than or equal to 500MPa, and the elongation is more than or equal to 19 percent.

Technical Field

The invention belongs to the technical field of metallurgy, and particularly relates to a production method for improving the flaw detection qualification rate of a continuous casting blank finished super-thick steel plate.

Background

The steel plate made of the continuous casting blank is low in cost and high in efficiency, high in production rate and high in yield, is suitable for large-scale continuous production, greatly reduces the cost compared with the steel plate made of steel ingots, and is suitable for batch continuous production, but the flaw detection qualification rate of the ultra-thick steel plate made of the continuous casting blank is 94-96% under the common condition, so that the method is not beneficial to the production of the ultra-thick steel plate, conforms to the current market situation for ensuring the stable production of the steel plate, meets the requirement of low-cost flaw detection steel plate, and is particularly important for researching the method for improving the flaw detection qualification rate of the ultra-thick steel plate made of.

The aim of improving the internal quality of the steel plate can be achieved by improving the purity of steel, reducing the content of harmful elements and impurities and controlling the subsequent heating and rolling processes.

Disclosure of Invention

The invention aims to provide a production method for improving the flaw detection qualification rate of a continuous casting blank finished super-thick steel plate. The invention effectively improves the flaw detection qualification rate of the steel plate by the ways of one-time aluminum feeding deoxidation, continuous casting starting electronic stirring, billet heating time control and single-pass large-reduction rolling in the steelmaking process, and is suitable for large-scale industrial production.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a production method for improving flaw detection qualification rate of a continuous casting billet finished super-thick steel plate comprises the following steps:

(1) a steel making process: after refining, Al is more than or equal to 0.010 percent, S is less than or equal to 0.010 percent, the refining period is controlled to be 40-50 min, the refining saddlebag is fed for 12-20 min, 0.8-1.2 kg of aluminum is fed once per t of steel for deoxidation, the vacuum degree is kept at 60-66 Pa in the vacuum process, and the vacuum keeping time is 15-25 min;

(2) a casting process: controlling the superheat degree of molten steel before casting to be 10-30 ℃, starting electronic stirring in continuous casting, wherein the electromagnetic stirring frequency is 3-5 Hz, and the electric stirring current is 400-500A, so as to prepare a continuous casting billet;

(3) a heating procedure: the time of a furnace hearth of the billet at a high temperature of 1200-1260 ℃ is 7-9 min/cm, and the total heating time in the furnace is 10-13 min/cm;

(4) a steel rolling procedure: controlling the single-pass reduction rate to be 12-15% by adopting a single-pass large-reduction rolling mode;

(5) slow cooling process: and (3) stacking the steel plates in time after rolling, wherein the stacking temperature is 400-450 ℃, the stacking time is 24-28 h, and unstacking is carried out for flaw detection.

The thickness of the steel plate obtained by the production method is 180-250 mm.

The flaw detection qualification rate of the steel plate obtained by the production method is 98-100% after flaw detection.

The steel plate obtained by the invention has the following properties: the yield strength Rel is more than or equal to 370MPa, the tensile strength Rm is more than or equal to 500MPa, and the elongation is more than or equal to 19 percent.

The performance index detection method of the continuous casting billet finished super-thick steel plate refers to GB/T1591-2008; the steel plate flaw detection standard is referred to NB/T47013.3-2015.

Adopt the produced beneficial effect of above-mentioned technical scheme to lie in: 1. according to the invention, the flaw detection qualification rate of the steel plate is effectively improved by the modes of one-time aluminum feeding deoxidation, continuous casting starting electronic stirring, billet heating time control and single-pass large-reduction rolling in the steelmaking process, and the flaw detection qualification rate of the steel plate reaches 98-100%. 2. The production method of the invention reduces the rejection rate, reduces the production cost of the steel plate, has excellent performance, obtains good economic benefit and is worth popularizing and using. 3. The steel plate obtained by the invention has the following properties: the yield strength Rel is more than or equal to 370MPa, the tensile strength Rm is more than or equal to 500MPa, and the elongation is more than or equal to 19 percent.

Detailed Description

The present invention will be described in further detail with reference to specific examples.