JPS60121055A - Continuous casting method - Google Patents

Abstract

PURPOSE:To obtain easily a roughly drawn wire having specified performance by installing a cooler and a heater between a parting position and a pouring position and cooling or heating selectively a rotary wheel for a casting mold thereby controlling the temp. CONSTITUTION:A molten metal 6 is poured from a nozzle 5 provided at the top of a rotary wheel 1 and a casting ingot 7 is released from the other end and is taken out. The ingot is continuously rolled to a roughly drawn wire in succession thereto. A thermometer 8, a cooler 9 and a heater 10 are successively installed between the releasing position of the ingot 7 and a pouring position and further a thermometer 11 for the casting ingot is installed in order to maintain the wheel 1 at a prescribed temp. The cooler 9 cools both side surfaces of the wheel 1 with water sprays and the heater 10 heats both side faces of the wheel 1 with gas burners. The temp. of the wheel 1 in the stage of receiving the molten metal is thus maintained within a prescribed range and the roughly drawn wire having specified performance is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention utilizes a belt-and-wheel type continuous casting machine to produce Aa, A(
Concerning the continuous casting method for alloys, CU, and CLI alloys, in particular, the rotating mold wheel is selectively heated or cooled during the period from demolding to receiving the mold to adjust its temperature, and the rotation at the time of receiving the mold is controlled. This invention relates to a continuous casting method in which the temperature of the ring is maintained within a predetermined range.

- In general, a belt boil type continuous casting machine uses a copper alloy mold rotary ring with a thickness of 10 to 30 mm with grooves on the outer circumferential surface, and an endless steel belt with a thickness of 2 to 3 mm on a part of the outer circumferential surface. A water-cooled mold is formed by contacting the mold, and a molten metal such as Cu or an alloy thereof is injected from one end of the mold.
The solidified ingot is released from the mold and continuously taken out from the other end.

However, in this conventional casting method, the temperature of the rotating wheel fluctuates periodically around the wheel, which affects the temperature of the ingot produced and the performance of the rough drawn wire obtained by rolling it, especially the tensile strength. This causes fluctuations in the temperature and causes fluctuations.

(Is the temperature fluctuation of the rotating wheel due to its eccentricity or at the start of operation?)
This variation is thought to be caused by thermal discontinuities, but this variation affects the thickness of the solidified shell that is produced, causing the temperature of the ingot to fluctuate. During casting, when molten metal is poured into a mold, its surface first solidifies to form a so-called solidified shell, but this solidified shell solidifies and contracts, creating a gap between it and the mold, which affects the amount of subsequent cooling. It will be close to the same extent. The amount of solidification shrinkage increases as the solidified shell becomes thicker, and the thickness of the solidified shell increases as the temperature of the rotating wheel decreases. Therefore, if the temperature of the rotating wheel during casting is low, the solidified shell that is produced will become thicker, the solidification shrinkage m will become large, the gap will become larger, and the amount of heat extracted from the rotating wheel will become smaller, resulting in a lower temperature of the ingot produced. It gets expensive. Moreover, when the temperature of the rotating wheel is high, the opposite phenomenon occurs and the ingot temperature becomes low.

For this reason, if the temperature of the rotating wheel differs depending on the location, the high-temperature part will first become higher due to good contact with the ingot, and conversely the low-temperature part will become lower due to poor contact, and this temperature will increase. The difference will not shrink if it remains as it is. For this reason, the temperature of the produced ingot continues to fluctuate throughout the rotation of the rotating wheel. Such fluctuations in the ingot temperature immediately lead to fluctuations in the rolling temperature, which causes variations in the tensile strength of the rough wire as described above.For example, generally speaking, if the ingot temperature differs by 10 degrees Celsius, the strength of the rough wire will vary by 1 to 2. ni'l
There will be variations in the range of f/mm2. Moreover, this variation in the tensile strength of the rough drawn wire causes variation in the strands after drawing, which is a big problem in fields where certain standards are required.

The present inventors became aware of the above situation and investigated various measures to stabilize the temperature of the ingot. As a result, the present inventors decided to selectively cool and/or heat the rotary ring for the mold, and the rotary ring during the reception of the mold. The inventors have discovered that the temperature of the ingot can be controlled within a predetermined range by keeping the temperature within a predetermined range, leading to the present invention.

That is, the present invention forms a water-cooled mold by bringing an endless metal belt into contact with a part of the circumferential surface of a mold rotating ring having a groove on the outer circumferential surface,
In a casting method in which A℃ or Cl-based molten metal is injected from one end of the mold, and the solidified ingot is released from the other end and continuously taken out, a cooler is used between the mold release position and the pouring position. A continuous casting method in which the temperature of the rotary mold wheel is maintained within a predetermined range during reception by installing a heater and selectively cooling and/or heating the mold rotary wheel to adjust its temperature. It is.

In the present invention, by keeping a rotating ring with a large heat capacity at a predetermined temperature during receiving the melt, the solidification form of the injected molten metal is significantly influenced and the temperature of the ingot is controlled through the above-mentioned phenomenon. However, such control is difficult with an endless metal belt, which has a small heat capacity and therefore has a small influence on the solidification form of the molten metal.

The present invention will be explained in detail with reference to Examples below.

Example 1 As shown in Fig. 1, a part of a rotating ring (1) for a copper mold with a thickness of 20 mm and a diameter of 1.4 cm that rotates in the direction of the arrow and has a groove on its outer circumference has a thickness of 2.7 mm. The endless steel belt (2) is moved in the direction of the arrow by a pressure wheel (3) and a tension roll or guide roll (not shown) to form a water-cooled mold (4). , molten alloy (6) is injected horizontally into the conductor through a nozzle (5) provided at the top of the rotating ring (1), and an ingot (7 ) was released from the mold and continuously taken out at a speed of 12 TIL/min, and then continuously rolled to a rough drawing line of 9.5Hφ.

At this time, in order to maintain the rotating ring (1) at a predetermined temperature during receiving the molten metal, a thermometer (8) and a cooler ( 9), a heater (io), and a thermometer (not shown) are installed in this order, and the ingot thermometer (11) is installed in order.
was installed. The cooler (9) cools both sides of the rotating wheel (1) with water spray, and the cooling unit length is 1 spray nozzle).It is installed over a length of 200mm (10 spray nozzles) with a cooling unit length of 20IIR. The amount of water was adjusted in advance so that the rotational wheel t=tit decreased by 5°C with a cooling unit length of 20#. The heater (10) heats both sides of the rotating wheel (1) with gas burners, and the heating unit length is 1 burner.
The main unit) was installed over a length of 20 m and 100 units (5 burners), and the amount of gas was adjusted in advance so that the temperature of the rotating wheel would rise or fall by 5°C by heating the heating unit length 20111II.

During the first few minutes of casting, the cooler (9) and heater (10) were not used, and the temperature changes of the rotary wheel (1) and the ingot (7) were measured with thermometers to understand their trends.

5 minutes after the start of casting, the temperature of the rotating wheel when receiving the metal is 1
Since the ingot temperature varies in the range of 20 to 150℃, the ingot temperature correspondingly varies in the range of 500 to 480℃, and the tensile strength of the rough wire varies from 17 to 20Kgf/mm2, the cooling closest to the mold release position Cover the spray nozzle of the container (9) so that it operates when the rotating wheel temperature is 125°C or higher, and then cover each spray nozzle with a rotating wheel whose grade is higher than 5.
The rotary wheel (1) was selectively cooled using the cylinders 1 to 1 so that they would operate sequentially with a time lag each time the temperature rose. As a result, up to 5 spray nozzles of the cooler (9) are activated, and the temperature of the ingot is stabilized in the range of 120 to 125°C when the rotating wheel (1) receives hot water, and the ingot temperature is maintained at 500 to 494°C. The tensile strength of the rough wire is adjusted to 16~17kg [7mm
2, and the variation could be suppressed to an extremely narrow range.

In addition, after this condition continued for about 30 minutes without operating the cooler (9), the temperature of the rotating wheel during hot water reception exceeded 125°C, so the cooler (one spray nozzle of 9) was installed. Activate to return to a stable state.

Example 2 A conductive A°C gold alloy was continuously cast under the same equipment conditions as in Example 1, and then continuously rolled to a rough wire. In this case, since the purpose was to manufacture a rough drawing wire with a tensile strength of 4F higher than that in Example 1, the heater (10
) to operate the gas burner below 145℃.
125 by operating each burner in sequence.
The rotating ring (1) was heated by heating the rotating ring (1) by heating the rotating ring (1) in a portion where the temperature was below 0.degree. As a result, the temperature of the rotating wheel during receiving the melt is stabilized in the range of 145-150°C, the ingot temperature is adjusted to 485-480°C, and the tensile strength of the rough wire is 18-199 f/mm.
2, we were able to suppress the variation within a narrow range.

In the above embodiments, the case where the rotational temperature is adjusted by using a cooler or a heater alone has been described.
It is also possible to carry out the cooling in combination, and it is also possible to carry out the cooling by an air cooling method, which is effective because the inner side of the rotating wheel can be directly cooled.

As described above, the present invention is applicable not only to the casting of alloys but also to other metal materials such as Cu, which makes it possible to easily obtain a rough wire with constant performance, and has a remarkable industrial effect. There are things.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an example of the casting method of the present invention. 1 Rotating ring for mold 2 Endless steel belt 3 Pressure wheel 4 Mold 5 Nozzle 6 Molten water 7 Ingot 8.11 Thermometer 9 Cooler 10 Heater Figure 1

Claims (2)

[Claims] (1) A water-cooled mold is formed by bringing an endless metal belt into contact with a part of the circumferential surface of a mold rotary ring having a concave groove on the outer circumferential surface, and from one end of the mold A, tl! In a casting method in which molten metal or Cu-based metal is injected and the solidified ingot is released from the other end and continuously taken out, a cooler and a heater are installed between the mold release position and the pouring position. 1. A continuous casting method characterized in that the temperature of the rotary wheel is maintained within a predetermined range during reception by selectively cooling and/or heating the rotary wheel to adjust its temperature. (2) The continuous casting method according to claim (1), wherein cooling is performed by water cooling or air cooling, and heating is performed by a gas burner.