JPS62282738A - Width rolling down method and width rolling down press device for hot slab - Google Patents

Abstract

PURPOSE:To prevent a temperature rise of an anvil as low as possible, and to extend a life of the anvil by preparing plural opposed anvils for pinching ans pressing a hot slab and bringing it to width rolling down, sliding it in the vertical direction of a mutual motion and pinching and pressing ti alternately, and bringing it to force cooling when it is not pinch-pressed. CONSTITUTION:An opposed anvil 1 for pinching and pressing a hot slab and bringing it to width rolling down is formed by plural anvils 1', 1'', and the slab in the direction vertical to the pinching and pressing direction by a hydraulic cylinder 4, and pinched and pressed alternately by the anvils 1', 1''. When it is not pinch-pressed, it is brought to forced cooling, and a rise of a temperature of the anvil is prevented as low as possible. By this operation, a life of the anvil is extended, and its manufacturing cost can be reduced.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention (Industrial Application Field) The technical content described in this specification regarding the hot slab width reduction method and width reduction press apparatus is In particular, we are proposing the development of a hot slab width reduction method and press equipment that are advantageous for long-term continuous operations.

Direct rolling () IDR) and hot charge rolling, which are achieved by synchronized operation of a continuous casting machine and a real strip mill, have great advantages such as energy saving, labor saving, and shortening of process days. for,
It is possible to increase continuous casting capacity, reduce surplus slabs by integrating materials, and significantly improve operational efficiency by synchronizing continuous casting and hot rolling.
As a countermeasure, there is a trend to introduce large reduction technology that increases the amount of width change in hot slabs.

(Prior art) As a method for width reduction of a hot slab, V-
Width rolling was performed using the H rolling method, but there were many problems, such as poor width rolling efficiency and increased crimp loss. Therefore, in recent years, a sizing technique (see JP-A-59-101201 and JP-A-60-203304) has been introduced as a more effective width reduction method in which the width direction of the slab is reduced over the entire length of the slab.

(Problems to be Solved by the Invention) By the way, in width reduction using the above-mentioned sizing technique, the following problems occurred in the anvil due to particularly long press operations.

In other words, since the anvil becomes hot, (a) deformation occurs due to the occurrence of a temperature gradient within the anvil, and wear due to softening during tempering is accelerated.

C. Heat cracks occur as the anvil surface cools rapidly.

20 Plastic flow occurs due to thermal stress on the surface.

For this reason, the life of the anvil is extremely short during width reduction of hot slabs, which is disadvantageous in that it leads to an increase in the cost of the real coil.

It is an object of the present invention to provide a width reduction method and a press apparatus that do not cause the above-mentioned problems even if pressing work is performed for a long time when a hot slab is width-reduced continuously over its entire length.

(Means for Solving the Problems) The present invention provides a means for reducing the width of the hot slab by forcing the width reduction anvils, which are paired with each other across the hot slab conveyance path line, to move toward and away from each other. A hot slab width reduction method (first invention) characterized in that, in carrying out the reduction, a plurality of pairs of width reduction anvils are prepared and used alternately by shifting them in a direction perpendicular to the above-mentioned mutual movement, Further, the present invention provides a plurality of pairs of width reduction anvils facing each other across a hot slab conveyance path line, an anvil holder that holds these width reduction anvils in a stacked manner, and an anvil holder that can be moved up and down. A hot slab width reduction press apparatus (second invention) comprising an attached slider block and a thrust device connected to the slider block to force the width reduction anvil to move forward and backward relative to each other.

FIG. 1 shows one side of the main part of a hot slab width reduction press apparatus suitable for carrying out the present invention, and FIG. 2 schematically shows the entire apparatus.

In the figure, 1 is a plurality of pairs of width reduction anvils (in this example, 1'
, 1"), 2 is an anvil holder that holds the width reduction anvil 1 stacked, 3 is a slider block, and 4 is a hydraulic cylinder that shifts the anvil holder 2 up and down. Also, 5 is the press device main body, and 6 is a slider. A connecting rod is connected to the back of the block 3, and 7 is a crankshaft, 8 is a reduction gear, and 9 is a drive device.

As shown in FIG. 1, this width reduction press device has an anvil holder 2 that has multiple pairs of anvils 1 (1', 1" in this example).
) are stacked and held, and are incorporated into the slider block 3 via a hydraulic cylinder 4 so as to be shiftable up and down.

Also, the slider block 3 to which the anvil holder 2 is attached is
is connected to a drive device 9 via a connecting loft 6, a crankshaft 7, and a speed reducer 8 on its back side,
The anvil 1 (1') is reciprocated along a pair of grooves formed in the press body 5.

1") is designed to force mutual advance and retreat movements (
(See Figure 2).

(Function) In order to reduce the width of a hot slab using the above device, first, as shown in Fig. 3, the opening degree W of the anvil 2, the amplitude 2a, and the conveyance per unit time of the hot slab given below are required. Set the distance in advance.

L=2a-α/lan θ L: Conveyance distance (m) θ: Entrance side inclination angle α; Margin (1m) Then, the mutual advance and retreat movement of the anvil 1 placed opposite the hot slab conveyance path line is controlled by Slider Pro. While forcing the reciprocating movement of 7-3, one cycle consists of releasing the anvil 1, transporting the hot slab, and reducing the width.By repeating this process, the hot slabs that are sequentially fed are continuously rolled to a predetermined width. The width is reduced to .

In particular, in this invention, when a predetermined width reduction process is completed, for example, each time the width reduction of one hot slab is completed, the hydraulic cylinder is controlled to move the anvil 1 located on the pass line of the hot slab.
' is shifted to position another anvil 1'' on the above pass line, and width reduction is then performed.

After the anvil 1'' is shifted, the anvil 1', which is in a standby state, is forcibly cooled down by a cooling device (not shown) during the width reduction by the anvil 1'' in preparation for the next width reduction (see Figure 1). ).

FIG. 4 shows an example of an operation pattern when two pairs of anvils 1 are prepared and the anvils 1' and 1' are alternately shifted each time a hot slab is rolled down by one width. The present invention advantageously prevents a significant temperature rise in the anvil that would otherwise occur during a long width reduction operation, since the anvil 1 is alternately used to perform width reduction each time a predetermined width reduction process is completed. It can be done.

Although not shown, a gap is provided between the stacked anvils 1' and 1' stacked on the anvil holder 2, or heat insulation and heat-resistant resin is inserted to minimize heat transfer between the anvils. It is desirable to have a structure.

(Example) Using the width reduction press shown in Fig. 2, the length was 10.5 mm.
m, width 15000, thickness 220m1. Initial temperature 1200
The width reduction of the hot slab at ℃ was carried out with a reduction amount of 3001 m.

The work time for width reduction was 3 hours, and anvils 1' and 1'' were shifted alternately each time one hot slab was width-reduced. During width reduction work, cooling water was applied to the anvils in standby mode. Forced cooling was performed by spraying mist.

For comparison, width reduction of the hot slab was carried out using a pair of anvils. After the width reduction work is completed, the surface temperature of the anvil,
Mises stress was investigated for each.

When width reduction is performed using a pair of anvils, the surface temperature is 507°C, and the Mises stress is 16 kgf.
/+u'', whereas when anvils 1' and 1'' were shifted up and down alternately to lower the width, the surface temperature was 421°C and the Mises stress was 65 kgf/1 m''. .

(Effects of the invention) According to this invention, it is possible to prevent as much as possible the temperature rise of the anvil that conventionally occurs when width reduction of hot slabs is carried out, thereby extending the life of the anvil and increasing the efficiency of width reduction work. At the same time, it is possible to reduce the manufacturing cost of the hot coil.

[Brief explanation of the drawing]

1 is a hot slab width reduction press apparatus suitable for carrying out the present invention; FIG. 2 is a perspective view of essential parts of a combination structure of an anvil 1, an anvil holder 2, a slider block 3, and a hydraulic cylinder 4; The figure is an explanatory diagram showing the method of width reduction of a hot slab, and FIG. 4 is a graph showing the operation pattern of width reduction. Figure 3 Customer Figure 4

Claims (1)

[Scope of Claims] 1. In performing the width reduction of the hot slab by forcing the width reduction anvils, which are paired with each other across the hot slab conveyance path line, to move toward and away from each other, the width of the hot slab is reduced. A method for width reduction of a hot slab, characterized in that a plurality of pairs of reduction anvils are prepared and used alternately by shifting them in a direction perpendicular to the above-mentioned mutual movement. 2. A plurality of pairs of width reduction anvils facing each other across the hot slab conveyance path line, an anvil holder that holds these width reduction anvils in a stacked manner, and a slider block to which this anvil holder is attached so that it can be moved up and down. and a thrust device connected to the slider block to force mutual forward and backward movement of the width lower anvil.