SU1225475A3 - Method of continuous casting of steel billet - Google Patents

Abstract

Steel is continuously cast in a mould comprising a grooved wheel (10) and an endless flexible belt (11) with cooling by sprays (S1 to S4). The casting and withdrawing of the bar and the cooling of the mould and bar are controlled to eliminate microsegregation in the bar and to provide a very uniform distribution of constituents and impurities, in particular oxygen, carbon, sulphur and manganese, in transverse section. The bar has improved properties for subsequent processing, in particular higher tensile strength. <IMAGE>

Description

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The invention relates to metallurgy, in particular to the continuous casting of metals and alloys.

The aim of the invention is to reduce microsegregation and ensure a uniform distribution of constituents and impurities.

The drawing shows a device for continuous casting of a steel billet, general view.

A device for continuous casting of a steel billet comprises a casting wheel 1 with a peripheral groove 2, which is closed at a certain portion of the periphery of the casting wheel 1 with an endless flexible band 3, which results in a closed 1; installer 4. The flexible tape 3 is held at a specified portion of the periphery of the casting portion 1 the supporting rollers 5-7 and moves with the casting wheel 1 as it rotates. A stitching device 8 with a groove 9 is located near the support roller 5. The casting wheel 1 and the flexible tape 3 are cooled by means of a cooling fluid coming out of the nozzles of the collectors 10-12, and the inside of the peripheral groove 2 is cooled by jets from the nozzles on the collector 13 The jet from each nozzle (or nozzle group) along the inside of the peripheral groove 2 can be individually adjusted: to change the volume of sprayed coolant and, therefore, to change the cooling rate of the metal in the crystal. - stator 4. Behind the supporting roller 7, there is a bending section 14 at the top, which is a means for straightening the cast steel billet 15 removed from the peripheral groove 2 of the casting wheel 1 after it leaves the closed part of the mold 4. The bending section 14 contains several supporting guide rollers 16, which may be driven and non-driven. In the bending section 14, side guiding rollers (not shown) can also be used to hold the cast steel billet 15 in a vertical plane. Above the support roller 7, a secondary cooling manifold 17 is installed to directly cool the workpiece, the outgoing and arcuate mold 4. Behind the secondary cooling manifold 17

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a guide roller 18 is installed, after which the billet REVENGES from the casting wheel 1. - The method of continuous casting of steel 5 is carried out as follows.

The molten metal from the casting device 8 through the chute 9 is fed into the peripheral groove 2 of the casting

10 wheels 1 rotating at a speed of 7.6-13.4 m / min. The feed rate of the liquid steel corresponds to the rotational speed of the casting wheel. When moving the liquid steel in the mold (5 4 to the latter serves coolant from the nozzles of the collector 10-13, and the amount of coolant supplied to the flexible tape 3 and the casting wheel 1, regulate .cyiH

20 controls the cooling rate of the molten metal. At the surfaces of the casting wheel and the tape, rapid cooling and hardening of the primary metal occurs, and a blister of hardened steel is formed, having an equiaxial granular structure; - h. Continuing the removal of heat from the partially hardened workpiece will cause the hardening of the liquid core; is happening.

3Q is gradual and uniform, with the result that a dextr1a or an equiaxial structure is formed in the direction from the shell to the center of the workpiece. - The workpiece is pulled out of the crystallizer at a speed of 7.6-13.4 m / min, and the liquid core of the workpiece is completely solidified by the time when it passes the last nozzle of the collector 17 and how it reaches the point located at the same level with the level of the bath liquid metal in the mold. The temperature of the outer surface of the workpiece at the exit from the closed part of the mold is not higher than 1372 ° C and not lower than 1038 ° C, and the complete solidification of the workpiece occurs within one minute after it is removed from the crystallizer. The billet coming out of the casting wheel has a shape that corresponds to the curvature of the arcuate mold, and the bending section gradually straightens the billet with an increase in its radius.

55 mostly trapezoidal blanks, but can be cast blanks and other forms.

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The advantage of the proposed method is micro-segregation and ensures that the distribution distribution is high: the cooling rate of the billet and output parts and impurities in the billet is high, and its extraction rate reduces its quality.

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Compiled by V. Bitkov Editor M. Nedoluzhenko Tehred O. Sopko Proofreader L. Patay

Order 1970/62 Circulation 757 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab, 4/5

Production and printing company, Uzhgorod, st. Design, D

Claims (1)

METHOD FOR CONTINUOUS CASTING OF STEEL Billet, comprising supplying metal to a wheel-type crystallizer, covered with tape on a part of its length, cooling, removing at least partially hardened billet from the mold and subsequent cooling of the billet by direct or indirect supply of coolant jets, characterized in that that, in order to reduce microsegregation and ensure a uniform distribution of components and impurities, the workpiece is removed from the mold with a speed of 7.6-13.4 m / min at a temperature of £ 10 38-1372 ° С, and then cooled to complete solidification within 1 min after removing it from the crystallizer. SU. „. 1225475 f