SU923729A1 - Unit for continuous casting of metals - Google Patents

Description

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

The known plant continuous casting mold comprising a casting wheel ⁵ with horizontal axle, with a groove of a rim shaping device in the form of a ring segment covering a chute preform solidification zone provided with a drive to impart the pro- ¹⁰ longitudinal vibrational motion of the filling and a device in the form of a fixed bowl for feeding metal into a chute by a vertically falling stream ζΐ). .

Known installation has a high porosity of the resulting ingot, not enough simultaneous and fine-grained structure of the ingot, significant volume segregation, ' _m

especially for complex alloyed alloys, the interaction of the poured metal with the surrounding gaseous medium in the casting process, instability

2

Structures and properties along the length of the ingot as a result of significant fluctuations in the level of the liquid metal in the mold at high casting speeds (up to 30 m / min), as well as a significant number and depth of surface defects of the ingot.

In addition, in a well-known installation, conditions are created under which a part of the ingot, solidified on the segment, is poorly separated and closes the mold.

The purpose of the invention is to provide control and regulation of the level of the liquid metal in the mold within the prescribed limits, as well as to obtain an ingot with a fine-grained structure.

This goal is achieved by the fact that in the installation of continuous casting of metals, containing a filling box and a mold in the form of a casting wheel with a horizontal axis and a groove along the rim, on which the forming ring segz 923729 is adopted

A vibrating drive unit that forms an annular segment is mounted on the rim of the casting wheel with the combination of the top generatrix of the rim and the leading edge of the forming annular segment, the casting box is equipped with a tray profiled along the chute of the casting wheel, and is provided with an overflow channel; one horizontal plane with the top forming the bottom of the wheel chute, the bottom of the box is 10-100 times larger than the cross-sectional area of the channel, and the bottom of the overflow channel is located at one level is the leading edge of the ring segment.

And besides, inside the filling box there is an inclined platform at an angle of 2-20 ° to the plane of the bottom of the box and with the top edge at the bottom of the overflow channel, opposite which is a sensor sensitive to visible or infrared radiation.

Also, the ring segment is provided with a graphite insert with a 'recess opposite to which a sensor sensitive to visible or infrared radiation is mounted.

The filling box is also equipped with an individual vibration drive.

FIG. 1 shows the installation, general view; Fig 2 - section aa

in fig. one; in fig. 3 "section BB

in fig. 1-, FIG. 4 - longitudinal

a section of the casting wheel chute and a ring segment at the place of mounting the graphite insert with a radiator; in fig. 5 “section BB of FIG. four.

The continuous casting plant includes a mold consisting of a casting wheel 1 with a chute 2 along the rim and a forming annular segment 3, and a curling box 4. The filling box 4 has a tray 5 made along the profile of the chute 2, an overflow channel 6, an inclined platform 7, heaters 8 and vibrodrive 9 · The casting box 4 is made and installed in such a way that the bottom of the box 4 with tray 5 and the top forming the bottom of the wheel groove (its projection on the drawing plane - point K) lie in the same horizontal plane. Filling the box 4 is closed by a casing 10, on which the heaters 8 are mounted, the filling pipe 11,

fitting 12 for the supply of inert or protective gas, electrocontact sensors 13 level control. Opposite the platform 7, a window 14 is made in the casing 10 and a sensor 15 sensitive to visible or infrared rays is mounted. Sprayers 16 are installed to cool the groove 2 inside the casting wheel, and a nozzle 17 is mounted on the outside of the wheel. · A formative ring segment 3 is mounted on the rim of the casting wheel with the upper part forming the rim of the casting wheel (its projection on the drawing plane - point B) with the leading edge forming ring segment. B. The forming ring segment 3 has a window 18 and a graphite insert, 19, is placed with local thinning-radiator 20. A sensor 21 sensitive to visible or infrared rays is mounted opposite the window 18 of segment 3. In the annular segment 3 is made of the channels 22 water

₂₅ cooling. Segment 3 is connected to the vibration actuator 23 and is pressed to the casting wheel by the device 24. The bottom of the overflow channel 6 of the filling box 4 is flush with the leading edge of the ring segment 3 (point B). These conditions exclude the possibility of an overflow of the gutter if the automatic control system is not precisely adjusted.

The area P of the bottom of the box is chosen ³⁵ depending on the cross-sectional area of the gutter section and is T = k $, where the coefficient k depends on the parameters of the system for regulating the level of the liquid metal in the junction box ⁴⁰ and is 10-100.

Mem greater molten metal surface, the lower speed level change, and control and adjustment system enables the pin ⁴⁵ · role of the level changes and keep it to within 1 mm and, depending on this control the flow of liquid metal.

However, when exceeding the bottom area

.50 boxes more than 100 times the cross-sectional area of the gutter increases the oxidation of the metal surface,) increases the power consumption for heating the metal in the box.

55 If the bottom area of the box is less than 10 times the cross-sectional area of the gutter, the metal level changes too quickly and the system

five

923729

6

control and regulation of the liquid metal level does not provide control and regulation.

The implementation of the inclined platform 7 inside the box at an angle ά = 2-20 ° to _{5 of} its bottom plane is determined by the following conditions.

The change in the level of the metal in the box causes the displacement of the metal border at the site-bevel and when the inclined platform-bevel is performed at an angle of less than 2 °, the liquid metal boundary is unstable, and when running at an angle of 20 °, the movement of the metal border will be insignificant, which is not < 5 allows you to control the level of metal.

Due to the directional flow of metal, the metal mirror, in the box-chute system, has a hydraulic slope of ₂₀ and a chute of 1.5'3 mm in diameter. Therefore, despite the location of the bottom of the overflow channel at the same level with the leading edge of the ring segment, in case of over- ₂₅ metal supply to the box, the overflow will be through the overflow channel.

The installation is as follows. zo

The heaters 8 of the filling box 4 and the casing 10, the drive (not shown) of the wheel 1, the lubrication nozzle 17 and the chute cooling sprayer 16, the wheels -1 are turned on. Inert gas _{35 is} fed through nozzle 12.

 Through the pipe 1], the liquid metal is fed into the filling box 4 and through the tray 5 enters the chute 2.

In the initial part of L of the gutter is 2 _4С .

(see Fig. 1) 20-80% of the ingot section hardening in the areas adjacent to the bottom and walls of the groove.

Next, after contact with the surface of the ring segment 3, the HA ₄₅ Chin solidification of the metal at a portion adjacent to the segment 3 · hardened on the surface of the metal segment 3 crust interested part of the ingot solidified in the trough 2.0t- _{$ 0}

the division of the crust from segment 3 is promoted by its oscillatory motion relative to wheel 1 under the action of vibrodrive 23- Liquid metal in filling box 4, chute 5 and in channel 2 is subjected to vibrations of a given amplitude and frequency under the action of vibrodrive 9 of filling box 4 'and vibrodrive 23 ring segment 3-Such an impact prevents bulk segregation and contributes to the grinding of grain in the ingot.

In the process of crystallization, the process of freezing the metal in the liquid bath takes place on the hardened part of the ingot moving with greater speed. This process eliminates the appearance of axial porosity in the ingot and also contributes to obtaining a fine-grained structure.

The control of the level of the liquid metal in the box 4 is carried out by electrocontact sensors 13 and the sensor 15, which is sensitive to visible or infrared rays. The sensor 15 reacts to a change in the position of the border of the liquid metal on an inclined platform 7 of the bottom of the filling box 4.

Using sensors 13 and known regulatory mechanisms (not shown), stepwise regulation of the supply of liquid metal to the filling box 4 is carried out. Sensor 15 is used to continuously control the flow of liquid metal.

Through the window 14 can also be carried out visual inspection of the position of the border of the liquid metal. This allows manual adjustment of the flow of liquid metal. In the event of a decrease in the level of the liquid metal in the crystallizer below the bottom of the filling box (Fig. 4), the level is controlled using a graphite insert

19 with local thinning (radiator)

20 and sensor 21. In the case of a decrease in the level below the permissible value, which may entail the appearance of defects in the “ingot <”, the area and boundary of the liquid metal contacts the emitter 20, the magnitude of the radiation flux and its boundary changes, which is detected by the sensor 21, which acting on the appropriate regulatory equipment, stops the casting process. After the curing process of continuously cast ingot 25 is removed from the wheel 1 and is subjected to further processing, such as stripping, rolling, drawing and winding.

Implementation of the proposed installation

at one of 15 plants 0CM will allow

get significant economic

effect (at least 12,000 rubles), due to

improve the quality of the ingot, higher 923729

cue time of continuous work, as well as lower capital costs of manufacturing and current operating costs.

Claims (3)

Claim 1. Installation of continuous casting of metals, containing a casting box and a mold in the form of a casting wheel with a horizontal axis and a groove along the rim, on which the forming annular segment with a vibration drive is installed, as follows: , in order to ensure control and regulation of the level of the liquid metal in the mold within the specified limits, as well as to obtain an ingot with a fine-grained structure and without axial porosity, the forming ring segment is mounted on the rim of the casting wheel with the combination of the upper the spreading rim with the leading edge of the forming annular segment, the filling box is equipped with a tray profiled along the trough of the casting wheel, and is made with an overflow channel, with the bottom of the box with the tray placed in one horizontal plane with the top forming the bottom of the chute of the wheel, the bottom of the box in 10-100 times the cross-sectional area of the gutter, and the bottom of the overflow channel is placed flush with the leading edge of the annular segment. five 2. Installation under item 1, characterized in that, in order to increase the sensitivity of controlling the level of liquid metal in the mold, inside the filling box a sloping platform is completed at an angle of 2-20 ° to the plane of the bottom of the box with the upper edge at the bottom of the overflow channel, opposite which is installed a sensor that is sensitive to visible 15 or infrared radiation. 3. Installation by π. 1, that is, in order to control the level of the Liquid metal in the mold, the ring segment is equipped with graphite an insert with a notch opposite which a sensor is installed that is sensitive to visible or infra-red radiation. 25 4. Installation according to Claim. ^ Characterized in that, in order to produce an ingot with a single-row and fine-grained structure, the casting box is equipped with an individual vibration drive.