TWI324952B - Electromagnetic stirring method for the continuous casting of flat metal products - Google Patents

Abstract

The electromagnetic stirring in a continuous casting installation for slabs, in which the mould (1) is equipped with an immersed casting nozzle (4) with lateral outlet holes (5, 5') directed towards the small faces, is carried out with the aid of sliding magnetic fields generated by polyphase induction coils arranged in the proximity of the cast metal. With the primary aim of favoring liquid metal exchanges at the heart of the solidification well (6) between the secondary zone (2) and the mould, one forces the establishment of a longitudinal metal flow in the central region of the cast product along two opposed collinear currents (10a, 10b). An independent claim is also included for a metal product with a elongated straight section from a continuous casting installation using this method of electromagnetic stirring.

Description

IX. DESCRIPTION OF THE INVENTION: TECHNICAL FIELD OF THE INVENTION The present invention relates to continuous casting of metals, particularly steel. In particular, electromagnetic stirring during casting of flat products (i.e., elongated sections), to a more precise degree, is a special distribution of the flow in the metal liquid pool using an applied magnetic field. [Prior Art] Please note that the "slim section product" is a metallurgical product with a width at least twice the thickness, especially a small slab of slab. It appeared in the field of continuous cast steel in the early seventies, and electromagnetic stirring has quickly established itself as an almost essential tool for controlling the flow in the liquid pool during solidification. It is remembered that the most commonly used principle is the Mhd (Magnetic Fluid Dynamics) principle, which is well known in the art, which utilizes the movement of a multiphase sensor, or, in general, several multiphase sensors placed adjacent to the casting (rotation) Or the magnetic field drives the liquid metal with its displacement. These inductors, suitably located at the metallurgical height of the casting machine, are supplied with current at an adjustable frequency, thereby providing a variety of mixing modes that can be matched to the requirements of the metallurgist. Furthermore, it is clear that the continuous advancement of metal-curing mechanisms during continuous casting has shown that the cyclic motion of liquid metal plays a role in the overall quality of the final cured product (ie, internal soundness, surface cleanliness or no debris, solidified structure, etc.). Important role = In this regard, the motion applied to the molten metal during continuous casting can be broadly divided into two types, depending on whether the mold is considered or underneath

Claims (1)

1324952 卜降: {月日日日明) is replacing I; X. Patent application scope 171-1 1 * Electromagnetic stirring method in the secondary cooling zone of continuous casting equipment for elongated metal products, the equipment The mold is provided with a submerged casting nozzle having a lateral discharge opening toward the small cast wall of the mold, the agitation method being carried out by a moving magnetic field generated by a multiphase inductor placed close to the cast metal, characterized in that For the purpose of exchanging the cooling zone (2) with the liquid metal inside the solidification tank (6) between the molds and the crucible, the longitudinal metal flow system is forcibly established in the 忒_second cooling zone, and the flow is unrestrictedly established in the center of the scale In the region, it becomes two reverse collinear flows (10a, 10b or 20a, 2〇b) and forms an integral liquid metal cycle having the shape of two upper lobe and two lower lobe "four-leaf clover", the four-leaf clover The upper leaf (Li, (4) extends into the mold - straight to the height of the jet (7, 7') ejected from the discharge holes (5, 5) of the submerged casting nozzle (4). Range method The longitudinal reverse collinear flow (1 〇a, l〇b) which is moved in a central manner in the central region of the casting cow is generated in such a manner that the two upper lobes (1), ") are extended: Into the mold - straight up to the height of the mouth '-(7, 7') ejected from the casting nozzle discharge holes (5, 5,) and merge with the jet to enhance them. The method of (4) of claim 1 is characterized in that the longitudinal reverse collinear flow (2, for example) which is concentrated in the central region of the tungsten is generated in such a manner that the two upper lobe (U, L4) Extending into the mold to reach the point of the casting nozzle... The jets (7, 7,) of the jets (5, 5) from the mouth of the mouth are again stacked on the jet to decelerate them. 26 1324952 Buckle (more) positive micropage 4. The agitation method of claim 1 is characterized in that the position of the longitudinal flow in the secondary zone is laterally displaced toward one or the other small side of the casting. A method of agitating according to claim 2 or 3, characterized in that the longitudinal metal flow system is utilized in the central region The moving collinear moving magnetic field produces two reverse collinear streams that are closer to or more apart from each other. 6. The agitation method of claim 2 or 3, characterized in that the longitudinal metal flow system is utilized in the casting The collinear moving magnetic field moving laterally across the width produces two reverse collinear flows, such as from the edge of the casting to the two opposing collinear streams closer to each other, A from the center of the casting to the edge. The method for feeding a mixture of the scope of the patent item i is characterized in that the magnetic field is generated by a multiphase linear inductor placed on a large casting wall facing the casting. 8. The stirring method according to item 7 of the patent application, the characteristics thereof Currents of different intensities are supplied to the inductors. The method of the first item of the patent scope is as follows, which is characterized in that the eight moving magnetic field is directly applied to the discharge hole (5, 5,) of the spray mold (1, 5). Metal jet (7, 7,). XI. Schema: As the next page. 27