SU531634A1 - Apparatus for cooling and granulating metal during casting - Google Patents

Description

one

The invention relates to the field of casting and granulation of metals and their alloys, and can also be used to cool and granulate all sorts of melts in other areas of technology.

Installations for the production of metal granules are known, comprising a fixed shell, a rotating nozzle with an aperture, a coolant tank, a coolant supply unit, a discharge nozzle and a collection of granules. In the installation, a rotating fluid funnel is created with the aid of a rotating disk on it, and the cooling medium iodouch assembly can be made in the form of an annular tube laid along the inner perimeter of the shell at its base, the tube having a slot facing the shell and tangential branch pipes inputs. However, in these plants, the temperature of the resulting granules is not controlled, the granules are not separated from the cooling medium, and the resulting granules need to remove residues of the latter, for example, by drying.

It is also known a device for cooling a cast metal, comprising a housing in the form of a double-sided diffuser, provided with a rotational drive about a vertical axis, and supply and discharge units for a cooling medium washing the inner surface.

enclosures. The advantage of the device is the lack of contact of the cooling medium with the meniscus of the ingot or billet, as well as the possibility of controlling the degree of cooling of the metal to be cast. However, the presence of a rotational drive makes the device cumbersome and difficult, since it requires precise centering of the case and careful care of the transmission elements, which quickly fail.

The aim of the invention is to simplify the design of the device. This is achieved by the fact that the device case is made stationary, and the node with iodine of the cooling medium - in

the form of nozzles connected to the top diffuser, the angle at an angle to its radius, constituting in the horizontal plane 60-90 °.

Pa figs. 1 shows the proposed device, a vertical section; in fig. 2 is the same, section A through A in FIG. 1 (in the plane of the supply of soyl).

Claims (1)

The body of the device consists of an upper diffuser 1, H1 of the diffuser 2 and a smooth transition section 3. Horizontal nozzles 4 are led to the upper diffuser 1 along the outer perimeter at an angle φ to the diffuser radius. The angle f can be changed in the range of 60-90 °. The housing is installed on the drain tank 5, having a drain pipe 6. In the bottom of the drain tank a collection of granules 7 is mounted. The device works as follows. A coolant is supplied through a pressure plate 4 at a certain pressure, which forms a rotating layer 8 on the inner surface of the housing, held by centrifugal forces. The cooling fluid passes the transition section 3 and is thrown by centroOne forces to the periphery of the lower diffuser 2, on the surface of which it is held by adhesion forces, and then flows into the drain tank 5, from where it is removed through the drain nozzle 6. 9 metal melt, which is crushed by the kinetic energy of the rotating liquid layer into granules of 10 certain sizes. The granules are also involved in rotational movement with the coolant and pass along a spiral path inside the upper diffuser 1. At the exit of the transition section 3, the granules fall out of the coolant layer and are directed to the collection of granules 7. Dropout from the cooling medium at the exit of the transition section The hull occurs due to the simultaneous action of gravity and inertia. Under the action of the centrifugal force of the granule ctc along the curvilinear generatrix of the transition section 3, the inertia forces of the granules are directed tangentially to the generatrix downwards. As a result of the combined effect of gravity and inertia, granules fall out of the coolant, since the metal granules have a much higher density than the liquid. The most optimal for creating a rotating layer of fluid inside the housing is a tangential supply of nozzles to the generatrix of the upper diffuser (90 90 °), since in this case the fluid flow already at the nozzle exit is tangential to the inner surface of the housing. By varying the angle of inclination of the nozzles to the radius of the diffuser, the degree of fragmentation of the melt jet and the size of the obtained granules can be controlled, since the velocity of the rotating layer changes at a constant flow rate of the cooling fluid. The layer of liquid receives the greatest speed of rotation with the tangential supply of nozzles (), since in this case the directions of the supply of liquid and the rotation of its layer coincide. When the nozzles are positioned at an angle to the tangent of the diffuser (), the direction of flow of the fluid does not coincide with the direction of rotation of its layer, and the layer and jets are mutually inhibited. Some loss of speed of the jet occurs also when flying along the chord n at the moment of encounter with the internal surface of the diffuser at an acute angle to its tangent (up to 30 at при 60 °). It is impractical to position the nozzles at an angle, as this increases the flight path of the jets before meeting the body and the stability of the rotating fluid layer is disturbed. It is also possible to regulate the splitting of the jet and the speed of rotation of the fluid in the housing if the nozzles are positioned not horizontally, but at a certain angle to the horizon. The temperature of the emitted granules is adjusted so that they can dry out when they fall into the collection of granules, i.e. they should not be cooled in a liquid below the boiling point of the latter. This can be achieved by naming the length of the pellets in the coolant by the height of the body or by feeding a jet of melt to different points forming the upper diffuser, as well as by adjusting the flow rate of the coolant, and operate on the pressure on the nozzles or their number. The advantage of the described device is the absence of rotating parts, which greatly simplifies its design, facilitates maintenance and creates conditions for improving the performance of the device by reducing downtime for repair and commissioning of components. In addition, the location of the feed nozzles at a certain angle to the radius of the diffuser allows the creation of a circulating coolant layer of varying thickness inside the body, held by centrifugal forces. By varying the angle of inclination of the nozzles to the radius of the diffuser, it is possible to regulate the fragmentation of the melt jet and the size of the resulting granules. The device allows to obtain ready-made granules with a predetermined temperature, which, by the drying operation, can be immediately sent for further use. In this way, the need for dryers is eliminated, maintenance personnel are released, and labor costs for the production of a unit of product are reduced. Apparatus for cooling and granulating metal during casting, containing a corus in the form of a double-sided diffuser, supply and discharge units for the cooling medium washing the inner surface of the body, characterized in that, in order to simplify the construction, the body is stationary, and the cooling medium supply unit in the form of opl, summed to the upper part of the diffuore tangentially at an angle of 60-90 °. V / ii: i5