CN1039371A

CN1039371A - Thickness is less than the production method of 10 millimeters steel band

Info

Publication number: CN1039371A
Application number: CN 89104780
Authority: CN
Inventors: 埃里希·霍夫肯
Original assignee: Thyssen Stahl AG
Current assignee: Thyssen Stahl AG
Priority date: 1988-07-14
Filing date: 1989-07-13
Publication date: 1990-02-07
Also published as: PT91157A; FI88591C; CA1325326C; DK4891A; RU2013184C1; PT91157B; AU620419B2; FI910136A0; JPH04500478A; AU3794689A; NZ229851A; ATE81042T1; FI88591B; BR8907544A; DK4891D0

Abstract

The present invention relates to the production method of thickness less than 10 millimeters steel band, by in the continuous ingot mould of cooling, pouring into a mould continuous casting steel billet, after continuous casting steel billet is pulled out in by ingot mould, the continuous casting steel billet that does not also solidify fully is extruded up to the strand shell inwall that has solidified and welds, simultaneously to reduce the thickness of strand shell greater than 40% degree of deformation.

Description

Thickness is less than the production method of 10 millimeters steel band

The present invention relates to the production method of thickness less than 10 millimeters steel band, it is by the continuous steel billet of cast in the continuous ingot mould of a cooling, from ingot mould, pull out the continuous casting steel billet that does not also solidify fully then, with its extruding, up to the strand shell inwall welding of having solidified.

In the prior art of this record No. 1647, (" Japan Patent digest ", the 8th volume, 210(M-328), on September 26th, 1984; Japanese patent application A5997747(A)), the continuous casting steel billet that does not also solidify fully of from ingot mould, pulling out, the strand shell that it has solidified is extruded, and is approximately the twice of the strand shell that has solidified up to the thickness of ribbon.In order to ensure the reliable welding of strand shell, according to the method for this prior art, on the strand shell, exert pressure, make the strand of from pinch roll, drawing equal two strand thickness of the shell sums.

Yet,, can only obtain the steel band that thickness is the 20-50 millimeter according to being applied to continuous casting steel machine to obtain not contain this known steps of shrinkage cavity strand.In a lot of application scenarios, this steel band is too thick.Because when thickness of strips is the 20-50 millimeter, on conventional cold-rolling mill, can not make its thickness be reduced to about 2 millimeters minimum thickness of requirement.

In the production of thin steel band, the prefabricated steel band that conventional method is produced is through cooling, is divided into suitable length again or around being the roll coil of strip after it solidifies fully.In the preparation that is next step rolling thin steel band, the roll coil of strip will pass through the heat treatment of middle back-heating type heating furnace, and it is even to adjust to temperature.Steel band is rolled in some mill traines.Because back-heating type heating furnace and a large amount of roll stands in the middle of needing, rolling thin steel band cost is still very expensive.Another shortcoming is, thisly offsets and then steel band heating and carries out, and scaling is wanted on its surface, and this just is difficult to the hot rolling effect that reaches satisfied.

Therefore, the purpose of this invention is to provide a kind of method and apparatus, can foolproof mode produce the high-quality steel band that thickness is the 1-10 millimeter by them.

The method that the problems referred to above have following characteristics is solved: the thickness of the strand shell that solidifies is to be reduced in strand being carried out the same operation of degree of deformation greater than 40% extruding.The four high stand of roll stand, particularly horizontal transmission by being placed in ingot mould outlet can be realized reducing of this thickness.

According to method of the present invention, from ingot mould, pull out the continuous casting steel billet that does not also solidify fully, in once-through operation, just can make thin steel band, it can be around being the roll coil of strip or further processing after suitable cooling.Because heating furnace and roll stand also do not require very big energy intensive device, produce steel band according to method of the present invention, cost is very cheap.

According to the present invention, cast different parameters of continuous casting steel billet and reducing of strand thickness of the shell, this two aspect is to coordinate so mutually, makes continuous casting steel billet to be extruded and don't to break, and in thickness reduced, the strand shell can stand sizable distortion.The thickness of shell is the 5-10 millimeter when if the intensity of cooling of poring rate and/or ingot mould need be controlled continuous casting steel billet being pulled out from ingot mould, and then the present invention is particularly favourable.Because it has guaranteed that the strand shell is enough strong when distortion takes place, the power in the time of can standing to be out of shape does not have crackle to form again.

If pull out the cast strand from the continuous casting ingot mould after, the strand shell that solidifies is extruded under the maximum temperature that allows, this will help to pour into a mould the homogeneous deformation of strand and the formation of satisfied structure.If the surface temperature of cast strand is higher than 1100 ℃, preferably 1200 ℃ to 1400 ℃, particularly 1300 ℃, can obtain satisfied result.Verified, the thermograde that the strand shell has perpendicular to casting billet surface is favourable.This thermograde is to be determined by the temperature that approaches solid-state temperature of casting blank surface temperature with cast strand inside.Because the characteristic of all steel is can the height stand under load during greater than 1200 ℃ in temperature, by keeping above-mentioned temperature, can prevent the crackle of casting blank outer cover when distortion.

When being extruded under the degree of deformation of cast strand at 50-80% the strand thickness of the shell is reduced, this helps forming satisfied especially rolled steel strip structure equally.For many application scenarios and/or relevant with some quality of steel be, by be lower than the extra reroll of 5% degree of deformation to steel band, help improving surface texture, meanwhile, also can make steel band form profile.

A characteristic of the present invention is to pour into a mould initial the reducing of slab thickness and carrying out in the ingot mould continuously.For this purpose, pull out when watering strand by the suitable structure in continuous ingot mould funnel-form district, the strand shell that forms at the broadside of ingot mould continuously moves together, or moves together at central area at least.The cooling of ingot mould is such adjustment continuously, makes the strand shell begin in the funnel-form district to form, and therefore the fusion that has of the strand that forms at this place is examined.Assurance makes the thickness of formed strand shell not hinder above-mentioned " moving together ", and this point is very important.

Embodiments of the invention are devices of producing steel band, do detailed explanation below in conjunction with accompanying drawing.

Fig. 1 is the side view of the device of implementation the inventive method;

Fig. 2 is a detail view, compares with Fig. 1, and yardstick has amplified, and has provided among Fig. 1 the details of regional device between continuous pouring ingot mould and roll stand.

Molten steel flows out from tundish 1, enters vibration ingot mould 2, vibration ingot mould 2 by funnelform top with formed the slab thickness that the distance between parallel cooling wall is poured into a mould corresponding to quilt by the bottom of parallel cooling wall.Because the ingot mould funnel-shaped structure, when pulling out the cast strand, in the funnel-form district, the strand shell that is just solidifying is moved together, thereby realizes tentatively reducing of cast slab thickness.Roll stand 3 is placed in outside the outlet of next-door neighbour's ingot mould, and by it, the strand shell that solidifies is pressed together, welding each other, and reduce thickness.For example, roll stand can be horizontal four-roller frame, its passive work roll 3a can adjust so that strand is done extruding by the fluid power cylinder, thereby reduces its thickness, determine the cross section carrying roller will with the narrow limit collaborative work in working roll 3a district.The diameter d of working roll 3a will be between 0.5 meter to 1 meter, and the distance D between the bottom of the start-up portion of bonding land and ingot mould 2 is less than 0.5 meter.These relations as shown in Figure 2.

Be placed in frame 3 back, then crooked guiding mechanism 4 is roll stand 5, and by it, the cast strand that solidifies fully is driven plain with about 5% so little degree of deformation.In the back of roll stand 5 are cooling systems 6, shear 7 and for coiling the winch 8 of steel band 9 usefulness.

Claims

1, thickness is less than the production method of 10 millimeters steel band, pour into a mould continuous casting steel billet in the continuous ingot mould by cooling, the continuous casting steel billet that will not solidify is fully pulled out from ingot mould then, it is squeezed, until the strand shell inwall welding of having solidified, it is characterized in that the thickness of the strand shell that solidifies is to be reduced in that the cast strand is imposed in the same operation of degree of deformation greater than 40% extruding.

2, in accordance with the method for claim 1, it is characterized in that the thickness of the strand shell that has solidified is to be that the extruding of 50-80% is reduced along with the cast strand is imposed degree of deformation.

3, according to claim 1 or 2 described methods, it is characterized in that, in order to reduce to pour into a mould slab thickness, when from continuous ingot mould, pulling out the cast strand, the strand shell that is solidifying at continuous ingot mould broadside, in the process of from continuous ingot mould funnel-shaped structure, pulling out, moved together by this funnel-shaped structure.

4, according to any one described method of claim 1 to 3, it is characterized in that the cooling of ingot mould will be adjusted so continuously, make the cast strand when from ingot mould, pulling out and before extruding, make its surface temperature between 1100 ℃ to 1400 ℃, preferably 1300 ℃.

According to any one described method in the claim 1 to 4, it is characterized in that 5, after the extruding, the cast strand also will stand degree of deformation and be approximately 5% reroll.

6, in accordance with the method for claim 5, it is characterized in that, be formed profile during the reroll of cast strand.