JPS6024741B2 - Manufacturing method for continuously cast slabs - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing different inner coin pieces by a continuous casting method.

In particular, the present invention processes coin coins that have been cast in a continuous casting line in a continuous casting line without changing or replacing molds, and efficiently produces mirror pieces with various types of insides. Relating to a method of manufacturing. The continuous casting method is extremely advantageous in terms of manufacturing efficiency, yield, energy saving, etc. compared to the so-called ingot casting method, but one of its drawbacks is that it usually only has a certain number of pieces, which are regulated by the mold shape. The problem lies in the fact that it cannot be manufactured.

In the downstream process, that is, the manufacturing process of hot-rolled steel sheets, etc., coin pieces (for example, slabs) with various plates are required depending on the size of the product. To produce a piece, the mold itself must be replaced, or changes made only within the mold.

However, replacing the mold means interrupting the work, which means that the advantages of the continuous casting method are lost. Furthermore, many proposals have been made recently to replace the mold during casting, but this inevitably reduces the speed of mirror insertion during the replacement process, and there is also the major problem of curling the coins. The above-mentioned problems can be solved by not replacing the mold or replacing the mold as described above, that is, by pressing the coin piece cast in a constant medium after solidification to make a coin piece with a predetermined inside. This makes it possible to perform highly efficient continuous casting using Hironaka's molds.

From this point of view, a method has been proposed in which a rolling mill is installed in series with a continuous casting machine to change the size of coins, but this method is wasteful because the processing capacity of the rolling mill is too high compared to the production capacity of the continuous casting machine. As a result, the reduction amount per rolling mill is limited to a maximum of 7Q due to the limitation of the angle of entry, and as a result, multiple rolling mills are required to carry out a major or medium-sized changeover, which increases equipment costs. invite.

Furthermore, rolling mills have many unresolved technical points, such as roll cooling problems, structural problems such as bearings for low-speed rolling, and installation space problems, making it extremely difficult to put them into practical use. The present invention aims to solve all of the above-mentioned problems of the conventional methods and to provide an epoch-making method for continuously manufacturing various types of mirror pieces efficiently and economically.

In the method of the present invention, the grain pieces after secondary cooling are pressed periodically by a hydraulic press in the pre-process of the cutting machine from both sides perpendicular to the movement direction of the coin coins in synchronization with the movement of the coin coins. The characteristics of

The twill pieces are divided into fixed lengths by periodic pressure from both sides and partially compressed into the specified size.Then, the twill pieces are cut to the desired length using a cutting machine, and then cut into any desired length required in the downstream process. Since it is made of a piece (for example, a slab) that has a medium and long length, there is no need to reduce the coin transfer speed, and it is possible to greatly improve operational efficiency.

FIG. 1 is a longitudinal sectional front view showing the mechanism of an example of an apparatus suitable for carrying out the method of the present invention, and FIG. 2 is a sectional plan view thereof.

In both figures, reference numeral 1 denotes a housing of a hydraulic press (hereinafter referred to as housing), which is used in a continuous casting line, especially a cutting machine 17 behind the pinch roll 16 in FIG. The coin coin 2 is placed at the front of the line, through which the coin piece 2 passes, and is guided by a guide 3 that is parallel to the line laid on the floor of the line so that the line can be freely moved back and forth within a certain range. There is.

Reference numeral 4 denotes a horizontal arm attached to the left-right symmetrical position of the housing, and is provided so as to move forward and backward intermittently toward the coin coin 2 passing through the housing 7 at regular intervals with rest periods in between. Generally, the horizontal arm 4 is operated by a driving device such as a cylinder, but in this example, the arm itself serves as the piston rod of the cylinder, which allows the pupil to be significantly miniaturized. In other words, the tail end of the horizontal arm 4 becomes a ram 5, which is movably connected to a concave head 6 formed in the side wall of the housing 1. By alternately pumping the liquid, the horizontal arm 4, which is movably passed through the cover plate 7, moves forward and backward repeatedly. 10 is a path through which the liquid passes, and 11 is a stroke detector.

Although not shown, a hydraulic device is connected to the liquid path 10'.
The horizontal arm 4 is automatically controlled by the signal from the detector 11.
The stroke is regulated and adjusted. A coin pressing pad 12 is provided at the tip of the horizontal arm 4, and the forward and backward movement of the horizontal arm 4 causes the mirror piece 2 to pass through the inside of the ujisogoo.
is pressed periodically in synchronization with the movement.

As shown in FIG. 1, this pad 12 is formed in a U-shape in longitudinal section, sandwiching the mirror piece 2 from above and below, and the surface 3 that supports the side surface of the coin piece 2 is shown in the cross-sectional plan view of FIG. like,
It has a so-called widening structure that curves outward from the middle at the rear of the line.

The former structure is such that when the pad 12 presses the twill piece 2, the coin piece 2
It is effective in suppressing the vertical bulge of the side edges of the
Moreover, if the latter structure is adopted, it is possible to prevent a difference in level from occurring between the pressed part and the unpressed part of the coin coin 2. FIG. 2 14 shows a pair of left and right cylinders installed parallel to each other on both sides of the line.The tip of the piston rod 15 is fixed to the front surface of the housing 1, and when the rod 15 is extended, the housing 1 is moved beyond its movement range. Position it at the end.

This cylinder 14 is provided so as to operate in a rest period between the forward and backward movement of the horizontal arm 4, and for example, its hydraulic equipment (not shown) is controlled by the signal of the stroke detector 11, and the horizontal arm 4 retreats to the left and right, the rod 15 is extended, and the hydraulic pressure is released except during the operating period, so that the rod 15 follows the movement of the housing 1. Next, in order to carry out the method of the present invention using the above-mentioned device, first, the stroke of the horizontal arm 4 is set based on the amount of replacement of the mirror piece 2, and the stroke of the mirror piece 2 is set.
The moving speed of and the length of the parallel portion of the pressing surface 13 of the pad 12 (
The operating cycle of the horizontal arm 4 is determined based on FIG. Now, set the moving speed of mirror piece 2 to 1. Shoes per minute, and if the length of the parallel part of the pressing surface 13 is 400 sails, then the coin piece 2 is on the pressing surface 13.
Since it takes about 1 minute to pass through the parallel part of , the operating cycle of the horizontal arm 4 is selected so as not to exceed this 1 mirror. Next, when the above device is operated, as shown in FIG. , ■
The housing 1 moves forward following the movement of the coin 2,
To prevent unreasonable tensile force or pushing force from acting on a coin piece 2.

When the compression is finished, as shown in Figure C, ■The pad 12 opens left and right, and at the same time as the opening, the cylinder (Figure 2, 14) operates, ■Returning the housing 1 to its old position as shown in Figure 3, A. .

Even after returning, the movement of the twill piece 2 continues, and the next compression is started before the pressing part of the mirror piece 2 finishes passing between the pads 12. According to the above method, since the inside of the coin coin is changed regardless of the casting process, there is no need to reduce the coin insertion speed when replacing the coin. This eliminates the restriction on the bite angle that is a problem when using a single device, and allows large to medium pressures to be achieved with a single device.

FIG. 4 schematically shows the cross-sectional shape of a coin when the coin is subjected to medium rolling by the method of the present invention and the method using a rolling mill.

The solid line is an example of the present invention, and the dotted line is an example of a rolling mill. As shown in the figure, in the method of the present invention, the thickness of the edge of the coin is considerably more inward (closer to the center of the coin) than in the rolling mill method.

If this raised portion approaches the end, it causes an increase in the thickness of the plate during rolling in the lower pressure stage. As in the case of the present invention, if the peak of the raised portion is located at a distance of 400 to 50 m from the end of the mirror piece, there is no concern about changes in the sheet during rolling. However, due to stacking of slabs, the peak of the rise (Fig. 4A)
If you want to lower the point), you can reduce the pressure using a presser roll or the like after applying pressure with a hydraulic press. An example of the method of the present invention using the above device will be described below.

The coin pieces were rolled down in the middle direction by 20 meters and 40 meters under the conditions shown below.

Continuous casting machine coining speed: 1.8 h/min Slab size: 25 mm thick x 160 mm medium Forging amount: 2 types of 20 mm and 40 mm on both sides Pressing cycle:
4 cycles/min Therefore, during one cycle, the mirror piece moves by the following amount.

Mirror loading speed 1.8h/min Travel distance 40Q Hydraulic device pad: with 5o taper hole type The cross-sectional shape of the coin in this case is shown in FIG.

Note that FIG. 4 shows the dimensions of the end of the coin shown in FIG. 5. An attempt was made to achieve the above-mentioned medium reduction by a rolling method, but the rolls slipped and the medium reduction could only be made from 60 to 9 yards.

With the method of the present invention, it is possible to change the pressure of coin coins in accordance with the rusting rate, and the operating rate of the continuous casting machine has been improved by 20%.

In addition, by changing the cross-sectional shape of the coins, the fishtail of the hot strip mill's roughing machine exit key was reduced, resulting in an improvement of 0.4%.

Furthermore, by using the technology for changing the size of various types of slabs of the present invention, which allows the production of various types of slabs in one chance, the amount of hot-strip bags charged to the hot strip mill (hot charge) can be increased, resulting in a large medium size of 2-way kca/ton. Energy savings were achieved. By implementing the method of the present invention as described above, there is no need to replace the mold to change the inside of the coin coin, and there is no need for downtime for changing the mold during the coin insertion process, which improves operational efficiency. It goes without saying that major improvements can be made in the coin coin yield by preventing the occurrence of rudders in the coin coins, and changes in the inside of the fin pieces at a pressing speed that follows the coin insertion speed of the continuous casting machine. By doing so, we achieved an increase in operating efficiency and a major or medium improvement in economic efficiency.Furthermore, structural problems caused by low-speed rolling bearings, etc. that were encountered when using a rolling mill were solved, and the installation space was also reduced. It is not necessary to use multiple rolling mills, which has the effect of significantly reducing equipment costs, thereby generating huge profits through energy conservation, and producing a very useful effect industrially.

[Brief explanation of drawings]

1 and 2 are longitudinal sectional front views and cross-sectional plan views showing an example of an apparatus suitable for implementing the method of the present invention, and FIGS. Fig. 4 is a diagram showing the relationship between the distance from the end of the coin and the amount of thickness increase, and Fig. 5 shows the case where the coin is rolled down in the middle direction by 20 and 400 ribs respectively. FIG. 6 is an overall view of a continuous casting apparatus illustrating the arrangement of a hydraulic press. Explanation of symbols in the drawings, 1: Housing, 2: Money piece, 3:
Guide, 4: Horizontal arm, 5: Ram, 12: Mirror piece pressing pad, 13: Pressing surface, 14: Cylinder. Figure 1 Figure 2 Figure 4 Vertical of Figure 5 Figure 6

Claims (1)

[Claims] 1. In front of the cutting machine of the continuous casting line, there is a hydraulic press that periodically presses the unheated continuously cast slab after secondary cooling from both sides perpendicular to the direction of movement of the slab in synchronization with the movement of the slab. In addition, the shape of the pad for pressing the slab of the hydraulic press is made into a U-shape that fits into the casting side, and the slab is held constant while suppressing the bulge on the upper and lower surfaces of the casting side end during pressing. A method for manufacturing a continuously cast slab, which comprises reducing the length to a predetermined width and then cutting the slab to a predetermined length.