The present invention relates to continuous casting systems for the manufacture of iron components, in particular metal bars with hollow profiles.
Metal bars are widely used in various areas of industry in various applications. Such bars may comprise a wide variety of formats, which vary according to the specific application of each case, in particular when produced by a continuous casting process. This wide range of applications is due to the fact that the process of continuous casting makes it possible to manufacture bars with varying dimensions, satisfying the needs of various areas of the industry.
For the manufacture of such bars, cast iron molding devices are generally used which receive cast iron at one end, mold and cool the cast iron, partially solidifying it, and release a cast iron segment into a second end. The described process is continuous, so as to form a continuous bar through this process. As already described, the profile of the mold can be varied so as to adapt to each application. Continuous casting processes, which are used for making compact metal bars, are widely known to those skilled in the art, and are widely described in specialized technical literature.
In addition, it will be appreciated that the current state of the art also already comprises continuous casting processes capable of making hollow or hollow metal bars, i.e., non-compact metal bars.
In this regard, the patent document U.S. Pat. No. 4,775,000 describes a continuous casting process of tubular parts by incremental reservoir of centrifugal material, wherein casting metal is centrifugally deposited adjacent to the outlet of the shape. For this purpose, a mold cooled by a fluid is provided, which causes the outermost region of the casting metal (which is in contact with the mold) to solidify, forming the cylindrical part. In addition, bearings positioned in a region subsequent to the exit of the mold are provided. These bearings are in contact with the part produced and exert force, so that it exits the mold.
Patent document WO 2015/089959, on the other hand, discloses a cast iron hollow duct and a method for making such a duct. To this end, use is made of a melting furnace connected to a rotating magnetic field generator and a crystallizer, wherein casting metal flows and is rotated in the crystallizer by the magnetic field. The crystallizer rapidly cools the temperature of the casting metal, making it solid and forming the duct. After leaving the mold, the formed duct is drawn by traction rollers, which causes the duct segments in formation in the crystallizer to, also, be rationed.
In order for the metal tube to be generated by continuous casting, it is necessary for the graphite mandrel to have at least a part of its base in contact with the indirect cooling. This allows the graphite to maintain its integrity and does not lose its mechanical properties. This continuous casting process allows the bars to have any length desired by the final customer, obviously limited to the logistics capacity.
It is from this scenario that the present invention arises.
The present invention aims to provide a system for the production of a hollow iron (hollow bar) component by skilled continuous casting whose internal surface finish is similar to the outer surface finish. This finish is only possible thanks to the continuous casting system coupled with the shape of the graphite mandrel which, through indirect cooling, maintains its mechanical properties allowing the tube to be extracted by traction without the mandrel breaking.
In order to achieve the above-described objects, the present invention provides a system for the production of a metal component by continuous casting, which comprises at least one mold integrated by at least one molding chamber and at least one cooling channel external to the molding chamber.
In general terms, according to the invention in question, said molding chamber comprises at least one outlet port of metal in solid state and said cooling channel comprises at least one inlet port of cooling fluid and at least one outlet port of cooling fluid.
Also provided is a match mold which, disposed at least partly inside the molding chamber of the mold, comprises a tubular body provided with at least one interface end and at least one inlet port of metal in liquid state, that the overall molding format is defined by the circumferential gap existing between the molding chamber and the match mold.
The detailed description set forth below makes reference to the attached figures and their respective reference numerals.
First of all, it will be appreciated that the following description will depart from a preferred embodiment of the invention. As will be apparent to a person skilled in the art, however, the invention is not limited to that particular embodiment.
However, the inventive core of the invention in question relates in particular to the mold (1), which, as especially shown in
Said mold (1), according to the preferred embodiment of the invention in question, comprises a molding chamber (2), provided with an outlet port (21) of metal in solid state, and a cooling channel (3) external to the molding chamber (2), provided with an inlet path (31) of cooling fluid and at least one outlet path (32) of cooling fluid.
In this context, it is noteworthy that the current state of the art already comprises molds for producing a metal component by continuous casting substantially analogous to said mold (1). Accordingly, detailed construction details relating to the molding chamber (2) and the cooling channel (3) are particularly omitted because they do not form part of the nucleus of the invention.
However, in the preferred embodiment, as shown in
As particularly shown in
Also as particularly shown in
The mold (1) of the system for producing a metal component by continuous casting disclosed further comprises a match mold (4) disposed at least partially within the molding chamber (2).
According to the preferred embodiment of the invention in question, said match mold (4) comprises a tubular body provided with an interface end (41) and an inlet port of metal in liquid state (42), which comprises a through channel disposed at the end of the interface (41) of the match mold (4).
Considering that the inflow of liquid metal into the molding chamber (2) occurs via the inlet port (42) of the match mold (4), it is found that the interface end (41) of the match mold (4) completely obstructs the end of the molding chamber (2) opposite the metal exit port (21) in the solid state.
It will be noted, therefore, that the inlet port (42) of the match mold (4) defines a fluid communication channel between the inside and the outside of the molding chamber (2) of the system for the production of a metal component by continuous casting.
On the other side of the chamber, opposite to the entrance orifice it is a piece called “puller” D. This part is intended to block the flow of liquid metal at the very moment the first filling of the chamber occurs. After this blocking, and waiting a few seconds, the metal cools and the handle itself will play the role of the first solidified part of metal.
This technical aspect is largely different from the known state of the art, after all, in all known molds (even those, which already comprise, in one form or another, an internal match mold) the liquid metal inlet always occurs by means of an orifice in the body defining the molding chamber (2) (usually in the opening of the molding chamber (2).
Preferably, the match mold (4) is concentrically disposed within the molding chamber (2) of the mold (1) and, consequently, the general molding shape is defined by the circumferential gap existing between the molding chamber (2) and the match mold (4). Also preferably, the match mold (4) is made of graphite. It is emphasized that the match mold (4) may have the desired profile, provided it is continuous.
Preferably, but never limiting, the system comprises a liquid metal reservoir (A) in fluid communication with the inlet port of metal in liquid state (42) in the liquid state of the match mold (4). Such a reservoir may comprise any known configuration, and is not a limitation of the present invention. Considering that, also preferably, the liquid metal reservoir (A) is at an upper level, it is considered that it is adapted to insert liquid metal into the molding chamber (2), through the metal inlet port (42) in liquid state of the match mold (4), by means of gravitational force.
Preferably, but never limiting, the system also comprises a traction device (B) adapted to exert tensile force on the metal body expelled through the exit port (21) of metal in solid state of the molding chamber (2).
Also, still preferably, but never limiting, the system also comprises a traditional cutting unit (C) and not limiting of the invention.
From the “traditional” process of producing a metal component by continuous casting, provided that a system composed of a mold (1) and match mold (4), according to the invention in question, it is possible to obtain a metal component of tubular (or hollow) shape, the “external” shape of which emulates the shape of the molding chamber (2) and whose “internal” shape emulates the shape of the match mold (4).
With regard to the finishing of the metal component generated by such process, it is possible to state that the internal finish of the hollow region is much higher than the finish obtained from the known methods, which facilitates the machining process, when the same it is necessary.
Numerous variations relating to the scope of protection of the present application are permitted. Accordingly, the fact that the present invention is not limited to the particular embodiments described above is reinforced.
Number | Date | Country | Kind |
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BR1020170154335 | Jul 2017 | BR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/BR2018/050243 | 7/17/2018 | WO | 00 |