US3261059A

US3261059A - Device for cooling the rod being formed in a machine for the continuous casting of metal rods of indefinite length

Info

Publication number: US3261059A
Application number: US243087A
Authority: US
Inventors: Properzi Ilario
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-12-13
Filing date: 1962-12-07
Publication date: 1966-07-19
Anticipated expiration: 1983-07-19
Also published as: BE626031A; DE1188769B; GB958761A; FR1340770A

Description

July 19, 1966 1. PROPERZ! 3,261,059

DEVICE FOR COOLING THE ROD BEING FORMED IN A MACHINE FOR THE CONTINUOUS CASTING 0F METAL RODS OF INDEFINITE LENGTH Filed Dec. 7, 1962 5 Sheets-Sneet 1 INVENTOR ILARIO PROPERZI July 19, 1966 1. PROPERZI 3,261,059

DEVICE FOR COOLING THE HOD BEING FORMED IN A MACHINE FOR THE CONTINUOUS CASTING OF METAL RODS OF INDEFINITE LENGTH Filed Dec. '7. 1962 s Sheets-Sheet 2 III Q IN VENTOR (\l ILARIO PROPERZI July 19, 1966 PROPERZl 3,261,059

DEVICE FOR COOLING THE ROD BEING FORMED IN A MACHINE FOR THE CONTINUOUS CASTING OF METAL RODS OF INDEFINITE LENGTH Filed Dec. 7. 1962 5 Sheets-Sneet 5 INVENTOR ILARIO PROPERZI United States Patent 3,261,059 DEVICE FOR COOLING THE ROD BEING FORMED IN A MACHINE FOR THE CONTINUOUS CAST- IN G OF METAL RODS 0F INDEFINITE LENGTH Ilario Properzi, Via Cosimo del Fante 10, Milan, Italy Filed Dec. 7, 1962, Ser. No. 243,087 Claims priority, application Italy, Dec. 13, 1961, 22,326/ 61 3 Claims. (Cl. 2257.4)

The present invention relates to a device for cooling the rod being formed in a machine for the continuous casting of metal rods of indefinite length.

The machine in question is of the type which comprises a drum rotatable on its own axis and provided with a peripheral groove: the molten metal, having been introduced into said groove at a point situated at a certain height, issues thereafter from the groove in the form of an ingot or rod, at a point a certain arcuate length away from said point of entrance.

An endless metallic belt or band contacts to the periphery of the drum along the length thereof from the point at which the molten metal enters the groove up to the point at which the ingot or rod issues therefrom, so that, at every instant, said belt closes the groove along said length of the drum and prevents the metal from escaping therefrom.

As it travels through the arc stretching from the point of entrance of the metal to the point of issue of the ingot (which points are fixed in space while the grooved drum rotates about its axis), the metal must solidify and, in order to do so, must be cooled.

One cooling system already provided on a machine of this type comprises a dispersion of heat inside the drum (by cooling through water circulation) and a device which directs jets of water on to a length of said belt covering the groove, striking the outer surface of said belt.

The production of ingot per unit of time depends on the speed of rotation of the grooved wheel, and this speed, for a given cooling system, cannot exceed a certain limit.

If the speed of the drum were to exceed said limit, the ingot issued from the drum would not yet be properly solidified and would hence be too soft to withstand without damage even the modest strains to which said ingot is subjected in order to extract it from the moulding cavity (i.e. the groove of the drum). An object of the present invention is to provide for more powerful cooling of the forming ingot. This brings the advantage not only of being able to increase the output of ingot by increasing the speed of the drum, but also of achieving a finer crystalline structure and less segregation in the ingot. The machine for the continuous casting of indefinite metallic bars according to the present invention comprises means for a preliminary cooling of the metal over at least a first part of the arc included between the two points respectively of metal inlet and ingot discharge, and is characterized in that there is provided a cooling device comprising means adapted to cause a length of belt, starting from a point in said are at which the forming ingot is in a state at least sufficiently pasty to give the ingot a certain mechanical strength, to be separated somewhat from said drum periphery, and means adapted to send jets of water such as will wash the surface of the length of ingot which is uncovered corresponding to the length of belt aforesaid which has moved a certain distance away from the periphery of the drum.

In order better to show the characteristics of the cooling device according to the present invention, an embodiment of said device will now be described with reference to the accompanying drawing wherein:

FIG. 1 shows a side view of a machine provided with the device in question;

3"26 1 9 Patented July 1 9, 1 966 FIG. 2 shows a cross-section of the device taken along the line II-II of FIG. 1; and

FIG. 3 shows a cross-section taken along the line IIIIII of FIG. 1.

The machine for the continuous .casting of metal rods of indefinite length, that is visible in FIG. 1, comprises a drum 1, rotatable on its own horizontal axis and driven by a motor.

Drum 1 comprises a peripheral portion 2 formed with a groove 3 (around the whole of its circumference) into which the molten metal for the formation of the ingot or rod is drawn. The metal in the liquid state 22 comes from a crucible 4 and is inducted into groove 3 at point A through a nozzle 5. An endless belt 6, supported on a wheel 7 and on drum 1 itself, is looped partially around the latter so as to form a closing wall of the peripheral groove 3 along an are which starts at point A and ter minates at a point B where the metal 22 issues solidified in the form of an ingot.

Said belt keeps the metal, which is first molten and then pasty, inside said groove, and thereafter the metal, or rather the ingot, leaves the groove at point B. Once clear of the drum beyond point B, the ingot moves onward over sustaining and guiding means (not shown), and is then sent to successive machining processes whereby the finished rod or bar is obtained.

In order to cool the metal which, while drum 1 rotates in the direction of arrow F, has to pass from the liquid to the solid state along said are AB, there has hitherto been provided a system based on a dispersion of heat inside the drum (i.e. cooling by the circulation of water inside the drum itself), and also on the cooling of belt 1 which is invested from the outside by jets of water directed thereonto. A device, schematically indicated by the part 8 in the drawing, provides in fact for the sending of jets of water onto the outer surface of the belt over a certain ar-c thereof.

Said system for dispersing the heat inside the drum, and also the schematically shown device 8, are in themselves independent of the invention but they also form part of the machine in question and provide for a preliminary cooling of the metal.

The device provided according to the invention, for a more rapid and effective cooling, comprising two members 9 placed at the two sides of the drum and symmetrical one with the other in respect to the centre plane of said drum, i.e. the lane perpendicular to the axis of the drum and dividing the drum ideally into two halves (the edge of said plane being indicated in FIGURES 2 and 3 by the line P). Each member 9 comprises two

parts

16 and 17 joined together by means of pairs of screws 18. Part 16 is formed with a cavity 19 extending along an are starting substantially from a point D and going up to the neighborhood of a point G at the end of member 9 near point B.

Cavity 19 is closed along one side by part 17 and is closed also at the two ends D and G of said are whereat said cavity starts and finishes.

A pipeline 20 admits water into cavity 19 whence the water, which enters said cavity along the whole length of said are DG, can issue only through a set of holes -21 formed at regular intervals along said arc. t

The axes of holes 21 are so oriented that the jet of water issuing from each of them can impinge on the metal 22 of the rod, as will be apparent hereinafter.

In the present embodiment, each pipeline 20 admits water into cavity 19 of the respective member 9 near the end D thereof, but the point of connection between pipeline 20 and cavity 19 can be at any desired point on are DG.

Similarly, the number, section and distribution of holes 21 along arc DG can be determined in various ways.

Each member 9 also carries a set of small rollers 23,

distributed along arc DG at equally spaced intervals, each of which is housed in a seat of member 19, protruding partly therefrom, and can freely rotate on its own axis.

The two members 9 are integral with each other so as to form a single body; this body, which extends from point E to point G, is pivoted on a fixed support 10 in such a manner that it can perform rotations about a horizontal axis indicated by the numeral 11.

Said body comprising the two members 9 is also pivoted at its end E to an arm 12 which is in turn pivoted at a threaded rod 13.

The lead screw of rod 13 is integral with a handwheel 14 and can rotate, without moving axially, inside a fixed support 15.

It follows that, by turning handwheel 14 in one or the other direction, rod 13 moves, in an axial sense only, upwards or downwards, thus causing the assembly of members 9 to rotate about axis 11 so as to depart from or approach the drum.

The working of the cooling device provided according to the invention, including said members 9, will now be described.

With rod 13 lowered and hence members 9 raised, belt 6 contacts the peripheral edge of drum 1 over the whole of arc AB. Under these conditions belt 6 closes the groove containing the metal. By raising rod 13 by means of rotating handwheel 14 which can be manually controlled by the operator, said body comprising members 9 (joined integrally together) rotates in such a manner that members 9 are lowered. In this manner, by pressing belt 6 with rollers 23, said members detach to a certain extent the belt itself from the periphery of the drum, along an arc extending substantially from D to B. The distance of belt 6 from surface 24 of the metal varies along arc DB, i.e. it is zero near D and gradually increases up to a value of some millimetres. The length of ingot which is in said are is thus uncovered.

By admitting water into cavity 19 of each member 9 (e.g. by turning on a suitable tap which sends water simultaneously to both cavities 19), the water, issuing from holes 21, impinges on the metal 22 (v. FIG; 3) of the forming ingot along arc DB, exercising thereon the greatest possible cooling action. In the working of the machine for the continuous casting of metallic rods in question, as soon as casting has started, the device comprising members 9 is set according to the conditions hereinabove described in which the belt is separated from the periphery of drum 1 along arc DB, and the tap which sends water into said members 9 is opened.

The metal which, as stated, enters in liquid form into the peripheral groove 3, begins immediately afterwards to cool, both on account of said dispersion inside the drum through the circulation therein of water, and on account of the jets of water sent by device 8 on to the outer surface Of belt 6.

The metal arrives at point D, where the length of belt that is detached from the drum begins, in a solid or almost solid state (i.e. pasty in practice) and, in any case, no longer liquid, so that it possesses a certain compactness at the moment when it enters into the portion of the groove 3 that is not completely closed by the belt, while still being at a relatively high temperature.

At this point an increased cooling action on said metal takes place.

Through the clearances which have been opened because of the aforesaid lowering of members 9 and hence of belt 6, the water plays with violent jets on the outer film of the metal ingot which is in the process of solidification. In this cooling zone at which it is in direct contact with the water (i.e. zone DB), the ingot is still practically sustained and contained by the walls of the mould, although there exists due to the shrinkage of the metal a space where the water can circulate round the ingot itself.

Although it is being struck with a certain violence by the jets of water, the ingot, since it is inside the mould, cannot break even though it is still in a pasty state.

There is thus a powerful cooling of the metal due to the direct contact thereof with the water.

The speed of cooling which can be obtained in this manner is the greatest possible, in view of the fact that the ingot shrinks and is struck by the water while still in the pasty state around its entire cross sectional periphery. This constitutes a new means whereby a metal can pass from the liquid to the solid state in a few seconds in the course of a regular production process turning out several tons per hour.

I claim:

1. In a machine for the continuous casting of molten metal in a continuous rod form having a rotatable casting wheel with a peripheral casting groove therein and a moving endless belt which contacts said wheel to define an enclosed casting area with the peripheral casting groove extending over an arcuate segmental length of the travel of the rotating wheel, in combination, the means for cooling said metal within a predetermined cooling portion of said segmental length of the moving enclosed casting area, into which the metal enters hardened to a degree that it is in a cohesive condition in the casting groove and will remain in that condition so that it may be separated slightly from the wall of the casting groove without breaking, said means cooling including apparatus comprising separating means for displacing the endless belt radially away from the wheel and casting groove in said predetermined cooling portion to an extent to provide for sufficient separation of casting wheel, bell and rod and permitting the rod in the casting groove to be positioned radially away from the same in said predetermined portion so that a cooling liquid may contact and cool the rod around its entire cross sectional periphery while the rod is still in said casting groove, and including also liquid-impinging means for impinging cooling liquid directly against the outside surface of the rod to cool the rod overits entire crosssection for the length which is maintained displaced from the casting groove over said predetermined portion of the enclosed casting area in the machine.

2. In a machine for the continuous casting of molten metal in a continuous rod form having a rotatable casting wheel with a peripheral casting groove therein and a moving endless belt which contacts said wheel to define an enclosed casting area with the peripheral casting groove extending over an arcuate segmental length of the travel of the rotating wheel, in combination, the means for cooling said metal within a predetermined cooling portion of said segmental length of the moving enclosed casting area, into which the metal enters hardened to a degree that it is in a cohesive condition in the casting groove and will remain in that condition so that it may be separated slightly from the wall of the casting groove without breaking, said means for cooling including apparatus having a part thereof on each side of the casting wheel adjacent the endless belt, separating means in each said part for displacing the endless belt radially away from the wheel and casting groove in said predetermined cooling portion to an extent to provide for sufficient separation of casting wheel, belt and rod and permitting the rod in the casting groove to be positioned radially away from the same in said predetermined portion so that a cooling liquid may contact and cool the rod around its entire cross sectional periphery while the rod is still in said casting groove, and liquid impinging means in each said part for impinging cooling liquid directly against the outside surface of the rod to cool the rod over its entire crosssection for the length which is maintained displaced from the casting groove over said predetermined portion of the enclosed casting area in the machine, said liquid impinging means in each said part including a cooling-liquid cavity extending longitudinally through the part and being closed at opposite ends thereof, with nozzle portions opening from the cavity to direct cooling liquid to the outside surface of the rod.

3. In a machine for the continuous casting of molten metal in a continuous rod form having a rotatable casting wheel with a peripheral casting groove therein and a moving endless belt which contacts said wheel to define an enclosed casting area with the peripheral casting groove extending over an arcuate segmental length of the complete travel of the rotating wheel, in combination, the means for cooling said metal within a predetermined cooling portion of said segmental length of the moving enclosed casting area, into which the metal enters hardened to a degree that it is in a cohesive condition in the casting groove and will remain in that condition so that it may be separated slightly from the Wall of the casting groove without breaking, said means for cooling including apparatus having a part thereof on each side of the casting wheel adjacent the endless belt, separating means each said part for displacing the endless belt radially out of contact with the wheel and casting groove in said predetermined cooling portion to an extent to provide for suflicient separation of casting wheel, belt and rod and permitting the rod in the casting groove to be positioned radially away from the same in said predetermined portion so that a cooling liquid may contact and cool the rod around its entire cross sectional periphery while the rod is still in said casting groove, liquid impinging means in each said part for impinging cooling liquid directly against the outside surface of the rod to cool the rod over its entire crosssection for the length which is maintained displaced from the casting groove over said predetermined portion of the enclosed casting area in the machine, and means connected with said apparatus for adjustably moving said parts radially from the rotating wheel to position the separating means therein a radial distance from the wheel related to the distance desired for the belt displacement from said wheel.

References Cited by the Examiner UNITED STATES PATENTS 315,045 4/1885 Lyman 2257 .4

594,583 11/ 1897 Wood 2257.4 2,659,948 1 1/ 3 Properzi 225 7.4 2,659,949 11/1953 Properzi 225 7.4 2,710,433 6/ 1955 Properzi 2257.4 2,714,235 8/ 1955 Brennan 2257 .4 2,8 65,067 12/ 1958 Properzi 2257.4 2,956,320 10/ 1960 Pulsifer 225 7.4

FOREIGN PATENTS 1,178,580 12/1958 France.

I. SPENCER OVERHOLSER, Primary Examiner.

MARCUS U. LYONS, Examiner.

V. K. RISING, Assistant Examiner.

Claims

1. IN A MACHINE FOR THE CONTINUOUS CASTING OF MOLTEN METAL IN A CONTINUOUS ROD FORM HAVING A ROTATABLE CASTING WHEEL WITH A PERIPHERAL CASTING GROOVE THEREIN AND A MOVING ENDLESS BELT WHICH CASTING GROOVE THEREIN AND FINE AN ENCLOSED CASTING AREA WITH THE PERIPHERAL CASTING GROOVE EXTENDING OVER AN ARCUATE SEGMENTAL LENGTH OF THE TRAVEL OF THE ROTATING WHEEL, IN COMBINATION, THE MEANS FOR COOLING SAID METAL WITHIN A PREDETERMINED COOLING PORTION OF SAID SEGMENTAL LENGTH OF THE MOVING ENCLOSED CASTING AREA, INTO WHICH THE METAL ENTERS HARDENED TO A DEGREE THAT IT IS IN A COHESIVE CONDITION IN THE CASTING GROOVE AND WILL REMAIN IN THAT CONDITION SO THAT IT MAY BE SEPARATED SLIGHTLY FROM THE WALL OF THE CASTING GROOVE WITHOUT BREAKING, SAID MEANS COOLING INCLUDING APPARATUS COMPRISING SEPARATING MEANS FOR DISPLACING THE ENDLESS BELT RADIALLY AWAY FROM THE WHEEL AND CASTING GROOVE IN SAID PREDETERMINED COOLING PORTION TO AN EXTENT TO PROVIDE FOR SUFFICIENT SEPARATION OF CASTING WHEEL, BELL AND ROD AND PERMITTING THE ROD IN THE CASTING GROOVE TO BE POSITIONED RADIALLY AWAY FROM THE SAME IN SAID PREDETERMINED PORTION SO THAT A COOLING LIQUID MAY CONTACT AND COOL THE ROD AROUND ITS ENTIRE CROSS SECTIONAL PERIPHERY WHILE THE ROD IS STILL IN SAID CASTING GROOVE, AND INCLUDING ALSO LIQUID-IMPINGING MEANS FOR IMPINGING COOLING LIQUID DIRECTLY AGAINST THE OUTSIDE SURFACE OF THE ROD TO COOL THE ROD OVER ITS ENTIRE CROSSSECTION FOR THE LENGTH WHICH IS MAINTAINED DISPLACED FROM THE CASTING GROOVE OVER SAID PREDETERMINED PORTION OF THE ENCLOSED CASTING AREA IN THE MACHINE.