JPH04500478A - Method for producing steel strip with a thickness of less than 10 mm - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Method for producing steel strip with a thickness of less than 10 aun The present invention produces copper strips with a thickness of less than 10 mm by casting a steel billet in a continuous cooling casting mold. Regarding the method for producing relates to a technique in which the inner walls of steel billet shells are pressed together until welded.

÷The shadow branch looks down Prior art (“Japanese Patent Abstracts” Volume 8, Nα210 (M-328) 1647°1 984.9.26: Described in Japanese patent application A3997747 (A) ) method, the solidified steel billet shell of the completely unsolidified steel billet drawn from the mold is The copper strip is crimped until its thickness is approximately twice the thickness of the solidified billet shell. Following the above Pressure welding according to the prior art method requires pinching to ensure welding of the billet shells. Roll the steel so that the billet pulled out from the roll has the total thickness of the two billet shells. Can be strongly performed on one shell.

However, this known method is not suitable for obtaining sinkage-free slabs in continuous casting. This is only applicable when obtaining copper strips with a thickness of at most 20 to 50 mm. 20～ Such a 50 m thick copper strip has a minimum thickness of approximately 2III mm as required by a normal cold rolling mill. It is too thick for many applications since it cannot be decompressed to 1.

In producing thin steel strip, a preliminary steel strip made by conventional means is cooled and After complete solidification, it is cut into steel plates of appropriate length or wound into coils.

In preparation for rolling subsequent thin steel strips, the coils are sent to an intermediate regenerator for heat treatment. and adjusted to a constant temperature. The copper strip is rolled in many buses. Thin Rolling steel strip by hand is difficult because it requires an intermediate regenerator and many rolling stands. Still very expensive. Other disadvantages in such rolling following heating of the copper strip are that The surface of the steel is oxidized and hot rolling cannot be carried out satisfactorily.

Therefore, the object of the present invention is to produce a high quality steel strip with a thickness of 1 to 10 mm in a very simple manner. The object of the present invention is to provide a method and apparatus that can be manufactured in stages.

This problem is caused by the thickness of the solidified billet shell when the billet is rolled with a reduction of >40%. The problem is solved by a method that is characterized by being compressed in a similar operation.

This reduction in thickness is carried out on the rolling stand, especially on the exit side of the ingot mold. This can be achieved with a horizontally driven quadruple stand.

According to the method of the present invention, a completely unsolidified steel billet is pulled out from an ingot mold. It is possible to fabricate thin steel strips with consistent operation, and the thin steel strips can be immediately After being cooled under certain conditions, it is wound into a coil or transferred to other processes. Main departure The production of steel strip by the method according to - It is very inexpensive as it does not require intensive equipment.

According to the invention, the various dimensions to be made in the casting of the billet on the one hand and the billet shell on the other hand thickness reductions are matched to each other, so that the billet can be reduced without breaking. This allows the billet shell to withstand considerable deformation during thickness reduction.

If the casting speed and/or cooling capacity of the ingot mold is controlled so that the ingot Especially if the billet has a shell thickness of 5 to 10 mm when drawn from the Gott mold. was found to be advantageous. This allows the billet shell to deform without crack formation. ensure that it has sufficient strength to resist the forces that occur between the two.

If the ingot is found to have congealed after the slab has been continuously drawn from the mold. If the slab surface temperature of more than 1100°C, preferably 1200-1400°C, especially 1300°C If so, a satisfactory result can be obtained. For the slab shell, the temperature is determined by the slab surface temperature. The temperature gradient within the slab and the final temperature up to the solidification temperature inside the slab are maintained perpendicular to the slab surface. It has been proven that it is advantageous to All steel products are subjected to high loads at temperatures above 1200℃. Because of the heavy weight, cracks in the slab surface during deformation are prevented by the aforementioned temperature maintenance. will be stopped.

Also to advantageously form a particularly satisfactory quality of the rolled copper strip, the billet shell The thickness of the slab is reduced while the slab is reduced at a reduction rate of 50-80%. many For some applications and/or some steel quality, additional re-rolling of the copper strip with a reduction of less than 5% is required. It is advantageous to improve the surface quality by providing .

At the same time, the copper strip is also given a contour.

According to one feature of the invention, the initial reduction in slab thickness occurs in a continuous ingot mold. It will be done. The slab shell formed on the wide side of the continuous ingot mold extends to its ends. , at least in the central zone, of the funnel-shaped zone of the continuous ingot mold. Depending on the configuration, they move simultaneously during the drawing of the slab. Cooling of continuous ingot mold The forming of the slab shell is arranged to start in the funnel-shaped zone, so that the molten core A slab shell with a is formed in place. Simultaneous movement like this is still possible It is important for the slab shell that the thickness builds up only in certain places. be.

An embodiment of the invention of an apparatus for producing copper strips is shown in more detail by means of the attached drawings. Described.

FIG. 1 is a side view of the apparatus for carrying out the method, and Figure 2 is an enlarged version of Figure 1, showing the continuous casting ingot mold and rolling star. 2 is a detailed view of the device depicted in FIG. 1 in the zone between the Molten steel is tan From the dish 1 flows into the vibrating ingot mold 2, which mold has a funnel-shaped upper part and It consists of a lower part with parallel cooling walls, the gap between which is equal to the thickness of the slab to be cast. I will. The funnel-like structure of the ingot mold allows the solidified piece shell to remain stable during the drawing of the slab. They move together in a funnel-shaped zone, thus reaching the point where the thickness of the slab is first reduced. Ru. A rolling stand 3 is placed immediately after the exit of the ingot mold, thereby solidifying the mold. The half shells are pressed together, welded together and reduced in thickness. rolling stun For example, the stand is a four-layer stand arranged horizontally, and the driving work roll 3 is A is for reducing the thickness of the slab 10 and can be adjusted with a hydraulic cylinder. Cut The support roll in cross section should be installed on the narrow side of the zone of the work roll 3a It is. The diameter d of the work roll 3a should be in the range of 0.5 to 1 m; The distance between the beginning of the interlocking zone and the bottom edge of the ingot mold 2 is 0.5 m. Should be less than These relationships are shown in FIG.

A curved guide 4 is arranged downstream of the rolling stand 3, in which a rerolling stand is placed. Tando 5 is placed and attached. This stand allows approximately 5% of the fully solidified slab to be Finished with a small rolling reduction. A cooling system 6 and a shaft are installed downstream of the rolling stand 5. -7 and a reel 8 for winding up the steel strip 9.

hot water Translation of the written amendment (Article 184-8 of the Patent Act) January II, 1991

Claims (6)

[Claims] 1. A steel billet is cast in a cooling continuous ingot mold and then pulled from the ingot mold. The fully unsolidified steel pieces that have been completely solidified are welded together until the inner wall of the solidified piece shell is welded. In the method for producing a steel strip having a thickness of less than 10 mm, the thickness of the solidified piece shell is > It is characterized by being reduced by the same process as welding slabs at a reduction rate of 40%. A method for producing an ungrooved steel strip with a thickness of 10 mm. 2. The thickness of the solidified piece shell is reduced by pressing the slab at a reduction rate of 50 to 80%. The method according to claim 1, characterized in that: 3. A slab solidified on the wide side of a continuous ingot mold to reduce the thickness of the slab. The funnel-like structure of the continuous ingot mold allows the shell to pull the slab out of the mold. 3. The method according to claim 1 or 2, characterized in that the method moves together with the other members. 4. The cooling of the continuous ingot mold is regulated so that the ingot is pulled out of the mold and , the surface temperature of the slab before being pressure welded is 1100 to 1400°C, especially 1300°C. 4. The method according to claim 1, 2 or 3, characterized in that: 5. A contract characterized in that, following pressure welding, the slab is re-rolled at a reduction rate of approximately 5%. The method according to claim 1, 2, 3 or 4. 6. Claim 5, characterized in that the slab is finished while being re-rolled. Method.