CN101422786A - Frame-space controlled cooling method during rolling hot-roll H sectional iron - Google Patents
Frame-space controlled cooling method during rolling hot-roll H sectional iron Download PDFInfo
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- CN101422786A CN101422786A CNA200810238804XA CN200810238804A CN101422786A CN 101422786 A CN101422786 A CN 101422786A CN A200810238804X A CNA200810238804X A CN A200810238804XA CN 200810238804 A CN200810238804 A CN 200810238804A CN 101422786 A CN101422786 A CN 101422786A
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Abstract
The invention relates to an inter-frame cooling control method for H-beam hot rolling, which belongs to the field of metal pressure machining. During the H-beam rolling process, under the condition that original rolling rules and tempos are not changed, partial cooling is carried out to the outer side of the flange of the H-beam by utilizing residual space between continuous rolling mill train frames and adopting a high-efficient gas spray cooling method. By the application of the technique, the temperature at the leg-waist connection part and the flange of the H-beam is lowered, temperature difference on a final rolling section of the H-beam is reduced, crystal grains at the leg-waist connection part and the flange are thinned, the residual stress of an H-beam product is greatly reduced, waves are prevented from being cooled by a web, and web cracking is reduced, therefore, the finished product rate of the H-beam is greatly improved and the comprehensive mechanical property of the H-beam is improved. The H-beam produced by the technique completely conforms to the requirements of the GB/T11263-2005 standard of 'Hot-Rolled H-Beam and Cut-T Section'.
Description
Technical field
The invention belongs to the stress metal manufacture field, the method of control cooling between a kind of hot rolled H-shaped rolling process mid frame is provided especially, be mainly used in hot rolled H-shaped production, in the operation of rolling, reduce H shaped steel leg waist connecting portion and edge of a wing temperature, homogenising H shaped steel finish to gauge section temperature.
Background technology
H shaped steel is as a kind of economic section shaped steel, compare with common I-steel have that modulus of section is big, bending resistance is strong, unit mass is light, good looking appearance, structure are convenient, save man-hour, reduce construction costs, can be processing regenerated etc. advantage, beam, rod structure member in industry and the civil buildings steel construction have been widely used in, the steel construction support bracket of industrial structure, industrial equipment such as petrochemical industry and electric power framework, the LARGE SPAN STEEL BRIDGE member, machinery, vehicle, boats and ships frame structure are in the engineering structures such as underground railway and overpass member.
Along with the fast development of Chinese society economic construction in recent years and being surging forward of domestic steel construction market; skyscraper constantly occurs with the large stadium facility and the standard of relevant H shaped steel design application technology is popularized; particularly the laws and regulations to environmental protection are progressively sound; the demand of domestic H shaped steel increases just day by day, and market prospects are very wide.
Before 1998, the hot rolled H-shaped also complete dependence on import of the domestic use of China.Along with being constructed and put into operation of two H type steel production line such as the H of Ma'anshan Iron and Steel Co., Ltd section steel works, medium shape factory of Laiwu Iron Co., Ltd., this situation obtains very big change.Domestic hot rolled H-shaped output was from zero to 1999 11.3 ten thousand tons, increase year by year afterwards, with the production line of having gone into operation and being about to build up at present, according to the condition of production in the first half of the year in 2008, the hot rolled H-shaped aggregated capacity of China will reach 1300～1,350 ten thousand tons.The domestic product specification that can produce covers large, medium and small specification H shaped steel, and maximum specification can reach about 1000mm.
Because the section complexity of H shaped steel, the rolling mill practice complexity, the rolled piece Temperature Distribution is very inhomogeneous in the operation of rolling, finish to gauge H shaped steel surface temperature difference can reach more than 150 ℃, the section temperature difference up to 200 ℃ about.The influence of various factors causes H sectional shape Tissue distribution inhomogeneous, the crystallite dimension maximum of R angular position wherein, and the web minimum, the edge of a wing is placed in the middle; Tissue distribution inhomogeneous makes H sectional shape mechanical property and decay resistance skewness, and position mechanical property and decay resistance that wherein crystallite dimension is big are low, local mechanical property that crystallite dimension is little and decay resistance height.
Simultaneously because particularly for the large scale of superior performance, the large H-shaped steel of little waist leg thickness ratio, there is bigger residual stress in the skewness of H shaped steel finishing temperature field.H shaped steel under the normal temperature state, the general performance of web position is a compressive stress state, the edge of a wing and web connecting portion show as tensile stress state, top flange shows as compressive stress state, the compression peak at web position is in the symmetrical centre position of H shaped steel length and width direction, reaches as high as more than the 200MPa.The existence of residual stress causes many quality problems easily, as: cause web cooling wave, have a strong impact on product design, reduce H shaped steel quality; Workpiece can produce distortion after cutting; Can produce the web crackle when flame cutting or welding, produce web when serious and burst; When using as members such as column or beams, anti-surrender descends or the like with bending resistance.
This shows that the control in H shaped steel temperature field is to improve H shaped steel performance, reduces waste product and quality accident, improves the key influence factor of lumber recovery.Existing H shaped steel is mainly still in the air cooling mode, H shaped steel rolls the high-order bit of section temperature, back and appears at " leg waist " connecting portion, because roll back H shaped steel " nose ", " kowtowing ", " lateral bending " phenomenon and the reason such as not steady when transporting on rolling the back transmission roller channel, the enforcement that causes H shaped steel to roll R angular position, back cooling device has difficulties.The surface temperature difference of large H-shaped steel finish to gauge simultaneously is more than 150 ℃, the section temperature difference up to 200 ℃ about.Under the situation that so the big finish to gauge section temperature difference has existed, if be difficult to the effect that reaches desirable by rolling the back cooling merely; At reversible tandem rolling unit, if be rolled cooling in the process by the outside, the edge of a wing before and after universal rolling unit control cooling device, because the unstability of shape in the H rolling of sectional iron process, cause equipment to tend to be broken, simultaneously for guaranteeing that H shaped steel cools off evenly end to end, need to carry out whipping in the H rolling of sectional iron process, change original H rolling of sectional iron rhythm, can have a strong impact on production efficiency.
Summary of the invention
For addressing the above problem, the present invention is according to the metastable end to end characteristics of H shaped steel rolled piece between operation of rolling mid frame, utilize remaining space between frame, set up and control cooling device between frame, cooling is forced in the outside, the H shaped steel edge of a wing in the operation of rolling, not only can avoid the collision that may occur between the H shaped steel and cooling device in the operation of rolling, guarantee not influence the original rhythm of production of H shaped steel, simultaneously can reduce H shaped steel edge of a wing finishing temperature, reduce the finish to gauge section temperature difference, improve the uniformity that H sectional shape structure property distributes, reduce H shaped steel and roll the back residual stress, increase substantially the lumber recovery of H shaped steel.
Technical solution of the present invention is, by being installed in the aerosol cooling device between H shape rolling mill frame, to the cooling that atomizes of the H shaped steel in the operation of rolling, atomizing cooling jet in the aerosol cooling device is fixed on the nozzle holder, in the reversible continuous rolling process of universal mill unit multi-pass, open edge of a wing aerosol cooling device between frame, nozzle needle sprays the outside, the edge of a wing of H shaped steel leg waist connecting portion correspondence, obtains the H shaped steel that the finish to gauge section temperature is evenly distributed.
Nozzle lateral extent outside the H shaped steel edge of a wing is 50～250mm; The height that will spray spot during injection is controlled in 3/4 flange width; Nozzle spray angle is 30～60 ° * 60～120 °.
Adopting the range hydraulic pressure of atomizing cooling is 0.2～1.0MPa, and discharge is 1.5～10.0Lmin
-1Air pressure is 0.2～1.0MPa, and compressed air require is 8.5～18.5m
3H
-1
Whole control cooling device can be fixed on the guide crossbeam, moves with roller system of rolling mill is whole when roll change, adopts the method for integral installation and overall pulling down.Nozzle quantity and nozzle holder length can require to preestablish according to distance between frame and cooling, and nozzle arranges that according to the length of rolled piece direction both sides nozzle height and width can be regulated according to different size.
H rolling of sectional iron process is:
1 with blank heating to tapping temperature, be generally about 1100～1250 ℃, carry out two roller split rolling methods, after cogging is finished, rolled piece is transported to the universal mill unit by transmission roller channel;
In the reversible continuous rolling process of 2 universal mill units, open edge of a wing aerosol cooling device between frame,, carry out the local aerosol cooling in the outside, the multi-pass edge of a wing, obtain the H shaped steel that the finish to gauge section temperature is evenly distributed according to corresponding specification product;
H shaped steel enters cold bed and cools off after 3 finish to gauges.
Principle of the present invention is to utilize the milling train gap, by the aerosol type of cooling efficiently, the part cooling is carried out in the outside, the H shaped steel edge of a wing, heat-conductive characteristic by means of steel, under the situation that does not change rolling procedure and rhythm, reduce the temperature on the H shaped steel leg waist connecting portion and the edge of a wing, the structural state of control deformed austenite, stop grain growth, the dislocation that fixed deformation causes, increase the degree of supercooling of phase transformation, when grain refining is organized on the H shaped steel edge of a wing, H sectional shape structure property is evenly distributed by cooling, and reduce H shaped steel residual stress, avoid web cooling wave, reduce the web cracking phenomena in the cutting process of the edge of a wing, reduce simultaneously and go up cold bed temperature, shorten cool time, enhance productivity.
Advantage of the present invention is: reasonably utilized remaining space between frame, rolling rhythm to H shaped steel does not exert an influence, utilized between the operation of rolling mid frame operation of H shaped steel steady relatively dexterously, the metastable characteristics of shape have reduced the risk of rolled piece and control cooling device production collision.Adopt the mode of aerosol cooling, the control that the outside, the H shaped steel edge of a wing is rolled in the process is cooled off, realize reducing the temperature on the H shaped steel leg waist connecting portion and the edge of a wing, H shaped steel finish to gauge section temperature is evenly distributed, to improving the comprehensive mechanical property of H shaped steel, the homogenising fractography distributes and has important practical value.
The product of producing by this technology, satisfy the requirement of country's " hot rolled H-shaped and subdivision T-steel " GB/T11263-2005 standard fully, and web cooling wave and web cracking phenomena have been reduced, reduced cold bed temperature on the H shaped steel, improved production efficiency, increase substantially economic benefit of enterprises, improved H shaped steel competitiveness of product.
Description of drawings
Fig. 1 is the three-dimensional sketch of edge of a wing aerosol cooling device between hot rolled H-shaped frame.
Fig. 2 is the three dimensional arrangement schematic diagram of control cooling device on production line.
In Fig. 2,1 is aerosol cooling device between frame, and 2 is UR (universal roughing mill), and 3 is E (edging mill), and 4 is UF (omnipotent finishing mill), and 5 is H shaped steel rolled piece.
Fig. 3 is the schematic diagram of rolled piece and nozzle ejection spot relevant parameter.
In Fig. 3, being described below of each parameter: Bf is a H shaped steel flange width; Tf is a H shaped steel edge of a wing thickness; Bw is a H shaped steel web inner width; H is for spraying the spot height; D is the distance in the nozzle and the outside, the H shaped steel edge of a wing; A is the minimum spray angle of nozzle; B is the maximum spray angle of nozzle.
Fig. 4 is a cooling path schematic diagram between H rolling of sectional iron process mid frame.
Fig. 5 is for adopting H shaped steel finish to gauge section temperature field, the present invention front and back cloud atlas.
The specific embodiment
Between the universal mill unit of certain H shaped steel manufacturing enterprise the aerosol cooling device has been installed, has been seen Fig. 1, shown in Figure 2, wherein hydraulic pressure is 0.4MPa, and discharge is 5.0Lmin
-1Air pressure is: 0.3MPa, compressed air require are 10.0m
3H
-1, each side arrange 5 * 4 nozzles.H shaped steel supplied materials specification is special-shaped continuous casting billet, and steel grade is Q235B, and product specification is HN800 * 300 * 14 * 26mm.The abnormity blank is heated to 1200 ℃ through heating furnace, after coming out of the stove, at first carries out reciprocal split rolling method by two roller pass milling trains, after enter the omnipotent reversible tandem rolling unit of UR-E-UF through transmission roller channel and carry out the reversible tandem rolling of 7 passages.Fig. 3 is the schematic diagram of rolled piece and nozzle ejection spot relevant parameter, the shape of spraying spot can be an ellipse, difformities such as rectangle, what adopt in this implementation process is oval (injection spot) nozzle, in the universal mill unit operation of rolling, the edge of a wing thickness T f of the first passage rolled piece is about 100mm, along with increasing of road number of times, the edge of a wing is attenuate gradually, final thickness is 26mm, nozzle will be increasing from the distance in the outside, the edge of a wing thus, H shaped steel web inner width Bw is 748mm, the first passage nozzle is 100mm from the distance in the outside, the H shaped steel edge of a wing, the predeterminable range of two side nozzles is: (748+100 * 2+100 * 2=1148mm), the final pass nozzle from the distance D in the outside, the H shaped steel edge of a wing is 1150mm: 175mm ((1148-800)/2=174mm).(A * B) is 45 ° * 90 ° to spray angle, guarantees that the height H of spraying spot in the operation of rolling is controlled in 3/4 flange width (Bf).
The cooling path of this specification product is seen shown in Figure 4.The first tandem rolling passage in the continuous rolling process after UF nips H shaped steel, is opened aerosol cooling device between frame, to the local aerosol cooling that is rolled in the process in the outside, the H shaped steel edge of a wing, after UR throws steel, stops to spray, and finishes the cooling procedure of the first tandem rolling passage; Next step enters the second passage continuous rolling process, after UR nips H shaped steel, opens aerosol cooling device between frame, enters the aerosol state of cooling between the frame of the second tandem rolling passage, after UF throws steel, stops the cooling of second passage.Each tandem rolling passage afterwards, the method for control cooling is identical between frame, and up to rolling end, H shaped steel enters cold bed and cools off after the finish to gauge.
At this specification product with finish to gauge after 20 seconds, as the time point of weighing result of use of the present invention, conventional state and adopt the cloud charts in H sectional shape temperature field, edge of a wing aerosol cooling back between frame is seen shown in Figure 5ly, the contrast of section temperature amplitude sees Table 1.By Fig. 4 and table 1 as can be seen: adopt in (the last figure among Fig. 5) before the present invention, the H sectional shape temperature difference is more than 180 ℃ under the conventional state.Behind employing the present invention (figure below among Fig. 5), by the local control cooling in the outside, the H shaped steel edge of a wing between operation of rolling mid frame, the finish to gauge section temperature difference is reduced to about 80 ℃, wherein the high-order bit (leg waist connecting portion) of temperature temperature reduces more than 100 ℃, and the minimum position of temperature (web centre) remains unchanged substantially.
Be cooled to room temperature after the finish to gauge of H shaped steel, check and analysis through residual stress, adopt the product of control cooling between frame, residual stress obviously reduces, wherein the residual compressive stress at web position reduces more than the 60MPa, has directly avoided the generation of H shaped steel web cooling wave, and, adopt the H shaped steel product after this invention, no web bursts phenomenon and occurs.Through tissue and mechanical property check and analysis, products obtained therefrom satisfies the requirement of country's " hot rolled H-shaped and subdivision T-steel " GB/T11263-2005 standard fully.
Table 1 adopts the amplitude contrast of the forward and backward H shaped steel of the present invention finish to gauge section temperature and the temperature difference
Claims (4)
1, controls cooling means between a kind of hot rolled H-shaped rolling process mid frame, it is characterized in that, by being installed in the control cooling device between H shape rolling mill frame, to the cooling that atomizes of the H shaped steel in the operation of rolling, the cooling jet that will atomize is fixed on the nozzle holder, in the reversible continuous rolling process of universal mill unit multi-pass, open edge of a wing aerosol cooling device between frame, nozzle needle sprays the outside, the edge of a wing of H shaped steel leg waist connecting portion correspondence, obtains the H shaped steel that the finish to gauge section temperature is evenly distributed.
2, control cooling means as claimed in claim 1 is characterized in that, nozzle lateral extent outside the H shaped steel edge of a wing is 50～250mm, and the height that sprays spot during injection is controlled in 3/4 flange width, and nozzle spray angle is 30～60 ° * 60～120 °.
3, control cooling means as claimed in claim 1 is characterized in that, adopting the range hydraulic pressure of atomizing cooling is 0.2～1.0MPa, and discharge is 1.5～10.0Lmin
-1, air pressure is 0.2～1.0MPa, air mass flow is 8.5～18.5m
3H
-1
4, control cooling means as claimed in claim 1 is characterized in that, whole control cooling device is fixed on the guide crossbeam.
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| CN200810238804XA CN101422786B (en) | 2008-12-03 | 2008-12-03 | Frame-space controlled cooling method during rolling hot-roll H sectional iron |
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| CN102029296A (en) * | 2010-09-30 | 2011-04-27 | 安徽工业大学 | Method for fast cooling low-carbon hot-rolling small H-shaped steel |
| CN101767113B (en) * | 2009-12-22 | 2012-09-05 | 马鞍山钢铁股份有限公司 | Cooling control device after rolling of hot-rolled H-shaped steel |
| CN103056175A (en) * | 2012-12-21 | 2013-04-24 | 山西新泰钢铁有限公司 | Alternative cooling control method of hot rolling H-section steel flange |
| CN106269910A (en) * | 2016-07-08 | 2017-01-04 | 山东钢铁股份有限公司 | A kind of hot rolled H-shaped bending control method |
| CN108188174A (en) * | 2017-12-18 | 2018-06-22 | 南通重矿金属新材料有限公司 | A kind of channel steel rolling production line |
| WO2019122986A1 (en) | 2017-12-22 | 2019-06-27 | Arcelormittal | Steel section rolling mill |
| CN112246888A (en) * | 2020-09-08 | 2021-01-22 | 福建泉州闽光钢铁有限责任公司 | Production method for improving surface quality of finish-rolled twisted steel |
| CN113546959A (en) * | 2021-07-20 | 2021-10-26 | 马鞍山钢铁股份有限公司 | Device and method for reducing hot-rolled H-shaped steel web waves |
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| CN101767113B (en) * | 2009-12-22 | 2012-09-05 | 马鞍山钢铁股份有限公司 | Cooling control device after rolling of hot-rolled H-shaped steel |
| CN102029296A (en) * | 2010-09-30 | 2011-04-27 | 安徽工业大学 | Method for fast cooling low-carbon hot-rolling small H-shaped steel |
| CN102029296B (en) * | 2010-09-30 | 2014-10-08 | 安徽工业大学 | Method for fast cooling low-carbon hot-rolling small H-shaped steel |
| CN103056175A (en) * | 2012-12-21 | 2013-04-24 | 山西新泰钢铁有限公司 | Alternative cooling control method of hot rolling H-section steel flange |
| CN103056175B (en) * | 2012-12-21 | 2014-12-17 | 山西新泰钢铁有限公司 | Alternative cooling control method of hot rolling H-section steel flange |
| CN106269910A (en) * | 2016-07-08 | 2017-01-04 | 山东钢铁股份有限公司 | A kind of hot rolled H-shaped bending control method |
| CN108188174A (en) * | 2017-12-18 | 2018-06-22 | 南通重矿金属新材料有限公司 | A kind of channel steel rolling production line |
| CN108188174B (en) * | 2017-12-18 | 2019-07-23 | 南通重矿金属新材料有限公司 | A kind of channel steel rolling production line |
| WO2019123320A1 (en) | 2017-12-22 | 2019-06-27 | Arcelormittal | Steel section rolling mill |
| WO2019122986A1 (en) | 2017-12-22 | 2019-06-27 | Arcelormittal | Steel section rolling mill |
| CN111448006A (en) * | 2017-12-22 | 2020-07-24 | 安赛乐米塔尔公司 | Section mill |
| CN111448006B (en) * | 2017-12-22 | 2022-06-07 | 安赛乐米塔尔公司 | Section mill |
| US11724295B2 (en) | 2017-12-22 | 2023-08-15 | Arcelormittal | Steel section rolling mill |
| CN112246888A (en) * | 2020-09-08 | 2021-01-22 | 福建泉州闽光钢铁有限责任公司 | Production method for improving surface quality of finish-rolled twisted steel |
| CN112246888B (en) * | 2020-09-08 | 2024-01-30 | 福建泉州闽光钢铁有限责任公司 | Production method for improving surface quality of finish-rolled deformed bar |
| CN114669606A (en) * | 2020-12-24 | 2022-06-28 | 宝山钢铁股份有限公司 | Internally cooled steel plate interruption prevention control method and rolling line |
| CN114669606B (en) * | 2020-12-24 | 2024-03-08 | 宝山钢铁股份有限公司 | Method for preventing interruption of intermediate cooling steel plate and rolling line |
| CN113546959A (en) * | 2021-07-20 | 2021-10-26 | 马鞍山钢铁股份有限公司 | Device and method for reducing hot-rolled H-shaped steel web waves |
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