JPH02263502A - Inter-stand edger mill and rolling method - Google Patents

Abstract

PURPOSE:To avert the degradation in production efficiency at the time of a roll exchange by providing flange parts which are relatively movable in the axial direction of vertical rolls on the top and bottom of the cylindrical parts of the rolls. CONSTITUTION:The edger mill 20 constituted of the vertical rolls (edger rolls) 21 consisting of grooved rolls is installed between strip mill stands and the edging of a strip is executed. The upper and lower flange parts 23, 24 which are relatively movable in the axial direction of the vertical rolls 21 are provided on the top and bottom of the cylindrical parts 22 of the rolls. The spacing between the flange parts 23 and 24 is adjusted according to the thickness of the strip. The inter-flange spacing is set in accordance with a previously determined rolling schedule. The edging effect is enhanced in this way, by which the amplitude accuracy is improved and the edge drop is lessened.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an inter-stand edger mill installed between strip mill stands for width reduction rolling of strip, and a rolling method using the same.

(Prior art) Conventionally, width reduction of rolled plates such as hot strips is generally performed by a width rolling mill installed near a roughing mill on the upstream side of the rolling line; Then, the thickness reduction performed downstream of the rolling line causes edge drops at the edges of the material, deteriorating the cross-sectional shape of the plate, and increasing the error between the target plate width of the product after rolling and the obtained plate width. There were problems such as a decrease in plate width accuracy.

Therefore, in recent years, consideration has been given to performing width reduction rolling between finishing stands on the downstream side of the rolling line to improve the cross-sectional shape and width accuracy of the strip.

For example, as shown in FIG. 7, horizontal rolling mill stands F4, F! An edger roll 1 consisting of a vertical cylindrical roll, that is, a flat roll, was installed between these rolling mill stands to perform width reduction rolling.

However, when width reduction rolling is performed on the strip between finishing stands, the strip thickness is smaller than the width of the strip, so the metal flow when width reduction is applied by edging is concentrated at the edge of the strip, forming dog bones. However, the deformation generally does not extend to the center of the board width. That is, as shown in FIG. 8, the edge shape of the strip 2 before etching is as shown by the dashed line, but after etching, the cross-sectional shape shown by diagonal lines is caused by the metal flow shown by the arrow in the same figure. A raised portion 3 is formed, and a dog bone 4 is formed at the edge of the strip.

Therefore, in the horizontal rolling performed after etching, the raised part 3 of the dog bone 4 is rolled down, and at that time, most of it flows outward in the sheet width (to the left in Fig. 8), resulting in a large In addition to causing the width to return, embossments occur at the ends, deteriorating the cross-sectional shape.

Therefore, since the width return during horizontal rolling after such etching is large, that is, the etching efficiency Δdirection/Δd(Δ
Since the amount of width adjustment after horizontal rolling (Δw: amount of edging) is low, it is necessary to increase the amount of edging in order to improve sheet width accuracy. However, if the amount of edging is increased, buckling is likely to occur in the width direction due to the thinness of the plate, resulting in a paradoxical phenomenon in which a large amount of edging cannot be achieved, which is a major obstacle in practical use. Ta.

Therefore, with respect to the edger mill between the finishing stands, as shown in FIGS. 9 and 10, the applicant uses a vertical roll with grooves, that is, a grooved edger roll, as the edger roll 11 to strip the strip I2. Inclined flange portions 13 are provided above and below the body of the vertical roll to reduce the width of the end portion of the roll.
The following relationship: 1.0≦it/lo≦1.3 and 2°≦θ≦20@(B
is the body length of the vertical roll, to is the strip thickness, and θ is the angle made with the horizontal line of the side surface of the inclined flange part of the vertical roll), and by reducing the width of the strip end with this vertical roll, the first As shown in the dogbone shape comparison diagram in Figure 11, compared to etching using a conventional flat edger roll, the raised part of the strip is formed closer to the inside of the strip width, and when the raised part is flattened during subsequent horizontal rolling. By suppressing the metal flow to the outside of the sheet width, as shown in the comparison diagram of etching efficiency in Fig. 12, the etching efficiency is further increased compared to the conventional edge roll, and the sheet width accuracy is improved. Developed technology to improve edge drop (patent application 1986-3001)
No. 16).

(Problem to be solved by the invention) According to this technology, it is possible to improve the etching efficiency and sheet width accuracy, and it is also possible to improve edge drop. (i.e., when the strip is processed with an edger roll having a hole shape as shown in FIG. there were.

In detail, firstly, the tip of the strip is usually not straight but undulating in the vertical direction, so when the tip of the strip passes through the edger roll, the tip of the strip touches the flange of the edger roll. There is a problem in that not only does it impede the passage of the strip, but it can also damage the edger equipment in some cases.

Second, the body length B of the grooved roll shown in FIG.
As mentioned above, 1.0≦B/lo≦1.3<However, t.

is a constant value that satisfies the plate thickness), that is, the interval B between the flanges cannot be adjusted, so for a specific edger roll, it can only be used for strips with a predetermined range of plate thickness that satisfies the above formula, It is necessary to change the shape of the edger roll depending on the strip thickness. Therefore, it is necessary to frequently replace the rolls depending on the rolling schedule.

If an unsuitable roll is used, e.g. the strip thickness t
The relationship between 0 and the body length B of the edger roll is °1.0.
≦B8. If B/lo<1.0 outside the range of ≦1.3, B8 in FIG. As can be seen from the diagram showing the relationship between and the edger roll separation force, the rolling reaction force (roll separation force) acting on the edger roll increases rapidly, and in some cases, the edger roll is damaged.

On the other hand, if B/lo>1.3, B in Figure 14
As can be seen from the diagram showing the relationship between /10 and etching efficiency, there is no significant difference in etching efficiency from the case where conventional flat rolls are used, and the advantage of using grooved rolls disappears.

Therefore, the edger rolls have to be replaced frequently depending on the strip thickness, but in this case, there is a problem of reduced production efficiency due to rolling interruptions when replacing the rolls, and it is also necessary for workers to enter the rolling line. There were also safety issues.

Therefore, in view of the above-mentioned problems of the conventional edger mill between finishing stands, it is an object of the present invention to reduce the width of a strip having a small thickness compared to the width with a next roll having a groove. , without having to change rolls according to the strip thickness, it is possible to constantly edt with the optimal hole shape, increase the edging efficiency, further improve the strip width accuracy, and further improve the edging with less edge drop. It is an object of the present invention to provide an edger mill between stands that realizes a plate cross-sectional shape and also eliminates troubles when the strip tip passes through, and a rolling method using the same.

(Means for Solving the Problems) The gist of the present invention is to provide an edger constructed of vertical rolls consisting of grooved rolls, which is installed between strip mill stands and performs width reduction rolling of the strip.
This is an inter-stand edger mill characterized in that flanges movable relative to each other in the axial direction of the vertical roll are provided above and below the body of the vertical roll.

That is, in the present invention, in an edge roll consisting of a vertical roll having a groove, the upper and lower sides of the body of the vertical roll are
It has a flange portion that is relatively movable in the roll axis direction, and has a configuration that allows the interval between the upper and lower flange portions to be freely changed to any length. In such a configuration, the spacing between the flange portions is
It includes means for adjusting and setting according to the strip thickness or according to a value determined based on a predetermined rolling schedule.

Furthermore, in order to maintain an optimal edger roll shape even against variations in the thickness of the strip during rolling, especially the decrease in thickness that occurs at the ends of the strip (so-called edge drops), it is preferable to install an edger roll upstream of the edger mill. A strip thickness meter is installed nearby, and the length of the roll body, that is, the spacing between the flanges, is finely adjusted during etching according to the actual value of the strip thickness measured by this thickness meter.

Further, according to the rolling method of the present invention, when the strip is etched efficiently in the edger mill between the finishing stands, at least until the tip of the strip passes through the edger roll, or adjacent to the downstream side, In order to improve threading performance, the spacing between the flanges should be widened to a specified length until the plate is caught in the installed horizontal rolling mill (
(preventing the tip of the strip from colliding with the flange),
After the strip tip passes through the edger roll,
Alternatively, after the tip of the strip is bitten by the horizontal rolling mill, the spacing between the flange portions is narrowed to a predetermined spacing, and the strip is subjected to etching rolling using grooved rolls.

(Operation) Next, the present invention will be described in more detail with reference to the accompanying drawings.

The finishing stand edger mill 20 according to the present invention has an edger roll 21, as shown in a longitudinal cross-sectional view in FIG.
A vertical roll with holes is used as the edger.
The roll 21 has an upper flange part 23 and a lower flange part 24 on the upper and lower sides of the body part 22, respectively. The upper and lower flange portions 23 and 24 are movable relative to each other in the axial direction of the edger roll 21.

In the illustrated example, the upper flange portion 23 is connected to the edger roll 2.
1, and a lower flange portion 24 is formed at the upper end of a cylinder 25 which is slidably and sealingly mounted around the edge roll 21. Oil seals 26, 27 are provided to ensure a tight seal between the edger roll 21 and the cylinder 25. The middle-edge roll 21 is provided with a radially annular piston head 28 which divides the internal cavity of the cylinder 25 into a first chamber 29 and a second chamber 30. A piston ring 33 is provided around the outer periphery of the piston head 28 to prevent fluid exchange between these chambers. Pressure oil supply/discharge pipes 31.3 are provided in the first chamber 29 and the second chamber 30.
2 are connected to each other. By supplying pressure oil from the pressure oil supply/discharge pipe 3 and discharging pressure oil from the pressure oil supply/discharge pipe 32, the gap B (see Fig. 10) between the upper and lower flange portions 23 and 24 is pinched, and the pressure is reduced. Oil supply/discharge pipe 3
By supplying pressure oil from 2 and discharging pressure oil from the pressure oil supply/discharge pipe 31, the distance B between the upper and lower flange portions 23 and 24 is widened. Roll position detector 3 for detecting the roll position according to the position of the hydraulic actuator 42, which consists of the chamber 29, 30 of the cylinder 25 and the piston head 28.
4 is a provision.

Therefore, according to the edger mill between finishing stands of the present invention, the distance between the upper and lower flange portions 23 and 24 provided above and below the body of the vertical roll of the edger mill can be adjusted.

Therefore, by adjusting the spacing between the flange parts to a predetermined interval according to the strip thickness at the lower flange part, it is possible to always maintain the optimum edger hole shape for the strip thickness. It is possible to prevent damage to the equipment due to a rapid increase in the rolling reaction force of the edger roll, which occurs when the strip thickness is too thick for the edger groove type, and it also prevents equipment damage, etc., which occurs when the strip thickness is too thin for the edger groove type. It is also possible to avoid deterioration in edging rolling and a decrease in product sheet width accuracy due to a decrease in the degree of restraint due to the hole shape.

In addition, by setting the spacing between the flanges to a value determined based on a predetermined rolling schedule, the shape of the edger hole between the stand parts where etching can be automatically optimized at any time. , there is no need to frequently replace the edger roll due to changes in strip thickness.
It is possible to avoid a decrease in production efficiency due to interruption of rolling when replacing rolls.

Furthermore, as another example, the spacing between the flange parts may be determined according to the actual value of the strip rg (particularly the strip end thickness) obtained from a strip thickness measuring meter placed upstream and close to the edger mill. By setting , it is possible to successively optimize the edge shape of the edger roll on-line, and it is possible to ensure high product strip width accuracy even when the thickness of the strip changes during rolling.

Further, according to the rolling method using an edger mill of the present invention, the interval between the flanges is made wider than a predetermined interval until the leading edge of the strip passes the vertical roll, and the leading edge of the strip passes the vertical roll. By restoring the spacing between the flanges to the predetermined spacing after this process, even thin, wavy strips can be edge-rolled using grooved rolls without problems such as bumps during threading. can.

Furthermore, as a rolling method in another example, the interval between the flanges is made wider than a predetermined interval until the leading edge of the strip is bitten by the horizontal rolling mill adjacent to the downstream side of the angel mill. By restoring the spacing between the flanges to a predetermined distance after the strip is inserted into the horizontal rolling mill, it is possible to perform edging rolling using slotted rolls, even for thin strips, without problems such as bumps during threading. It can be carried out.

Next, the effects of the inter-stand edger mill of the present invention will be described by way of examples.

Finishing mill F1 using the edger mill of the present invention for hot rolling
, one example implemented between F2 is shown in Figure 2, and another example is shown in Figure 3.
The shape of the edger roll in this case, shown in each figure, is as shown in FIG.
'1100n, roll body diameter = 200+*m, and strip thickness between rolling mills F and ~Ft is 20~40+++
s, and the distance B between the flange parts is 1 of the strip thickness t0.
．． It was set in the range of 0 times to 1.3 times. As for finishing rolling mills F8 and F2, -S type four-layer horizontal rolling mills were used.

Example 1 In the example shown in FIG. 2, the edger roll shown in FIG. 1, which can freely change the spacing between the flanges using hydraulic pressure, was installed between the finishing mills F1 and F2, and was set in advance. Based on the rolling schedule S, the main processing unit 40 determines the optimum edger roll hole shape for the strip thickness between the finishing mills F1 and F2, and the hydraulic actuator control device 41
The hydraulic actuator 42 was operated to change the distance B between the flange portions of the edger roll 21 to a predetermined value.

As a result, even if the strip thickness between finishing mills F1 and F2 changes, the width of the strip is always reduced with the optimum edger roll groove shape in terms of width adjustment efficiency and equipment maintenance, without having to replace the edger roll. I was able to do it. Note that the data from the roll position detector 34 is fed back to the hydraulic actuator control device 41.

Embodiment 2 In the embodiment shown in FIG.
A thickness measuring meter 43 is installed close to the upstream side of the edger roll 21, and this detector actually measures the thickness of the strip end and inputs it to the main processing unit 40, which determines the hole shape of the edger roll. Corrections were made when calculating the optimal value of. Other aspects were substantially the same as in Example 1 shown in FIG.

As a result, even if plate thickness fluctuations occur due to edge drops or temperature drops at the ends of the strip, they are sequentially fed back to the main processing unit 40, and the spacing between the flange portions of the edger roll 21 can be instantly corrected online. Compared to the case of Embodiment 1 shown in the figure, the plate width adjustment efficiency can be further optimized.
It was found that the product plate width accuracy could be further improved.

Next, an example in which the rolling method using an edger mill of the present invention is carried out in a finishing mill P1.22 for hot rolling is shown in FIGS. 4 to 6. The shape of the edger roll in this case is as shown in FIG.
The roll body diameter was 100mm, the roll body diameter was 200φ, the strip thickness between the rolling mills P and P2 was 20III11, and the distance B between the flanges was 21+am as a predetermined distance. In addition, for finishing rolling mills F1 and F2, general 4
A heavy horizontal rolling mill was used.

Embodiment 3 In the embodiment shown in FIG. 4, the interval between the flanges is first made larger than a predetermined interval, and a sheet passing detector (non-contact type) is installed close to the upstream side of the edger roll 21.

The passing of the leading edge of the strip is detected by this sheet passing detector and inputted to the hydraulic actuator control device 51. At a predetermined timing, after the leading edge of the strip has passed the edger roll 21, the edger is The spacing between the flanges of the rolls was returned to the predetermined spacing. The above predetermined timing needs to be changed depending on the strip threading speed, and it is also necessary to adjust the set interval between the upper and lower flanges during edge rolling according to the strip thickness, but these are based on the data input in advance. After calculation was performed by the command control device 52 based on the above, a control signal was input to the hydraulic actuator control device M51, and the hydraulic actuator 42 was operated.

In FIG. 4, the width of the strip may be reduced by the edger roll 21 until the distance between the upper and lower flange portions of the edger roll 21 reaches a predetermined distance, and during this time, no etching is performed. The edger roll 21 may be retracted to a position slightly apart from both edges of the strip, and the edger roll may be started only when the distance between the upper and lower flange portions of the edger roll is set to a predetermined distance.

Embodiment 4 Also in Embodiment 4 shown in FIG.
0 is arranged close to the downstream side of the edger roll 21,
After the strip passing detector detected the leading edge of the strip, the hydraulic actuator 42 was operated via the hydraulic actuator control device 51 to return the spacing between the flange portions of the esosure roll 21 to a predetermined spacing.

Embodiment 5 In Embodiment 5 shown in FIG. 6, a load cell 53 for detecting strip passing is incorporated in the horizontal rolling mill F2 located downstream of the edger roll 21, and this load cell 53 allows the leading edge of the strip to be placed in the horizontal rolling mill F2. After confirming that F2 was caught, the hydraulic actuator 42 was operated via the hydraulic actuator control device 51, and the distance between the flange portions of the edger roll 21 was returned to a predetermined distance. It goes without saying that in this embodiment as well, the distance between the flange portions is initially made larger than a predetermined distance.

Although several embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to these embodiments, and that various changes can be made without departing from the gist of the present invention. stomach.

(Effects of the Invention) As described above, according to the inter-stand edger mill of the present invention and the rolling method using the same, the upper and lower flanges of the grooved roll of the edger mill can be moved relative to each other, and the By setting the spacing to the optimum value from the viewpoint of width adjustment efficiency and equipment maintenance according to the strip thickness at the edge part, product 4Fj, thickness accuracy can be improved, and frequent changes due to strip thickness changes can be achieved. Etsiya
There is no need to replace the rolls, and it is possible to avoid a drop in production efficiency due to rolling interruptions when replacing the rolls.

Furthermore, by keeping the spacing between the flanges wider than the predetermined distance until the leading edge of the strip passes a predetermined position such as a grooved roll, troubles during threading of the strip can be eliminated, and furthermore, the leading edge of the strip can be After passing through the edger roll, the gap between the flanges is returned to a predetermined distance and etching is performed with a slotted roll, thereby increasing the etching efficiency, improving the width accuracy, and improving edge drop.

[Brief explanation of drawings]

Fig. 1 is a partial longitudinal cross-sectional view of an inter-stand egger mill according to the present invention; Figs. 2 to 6 are layout diagrams of an egger mill showing embodiments of the present invention; Fig. 7 is a conventional flat egger mill; Arrangement 2 of edger mill between stands by rolls; FIG. 8 is a schematic explanatory diagram of the dogbone shape formed by the edger mill of FIG. 7; FIGS. 9 and 10 are respectively Layout and configuration diagram of an inter-stand edger mill using grooved rolls proposed in 2003: Figure 11 shows the interstand edger mill using grooved rolls shown in Figures 9 and 10 and the conventional flat edger mill shown in Figure 7. A diagram comparing the dogbone shapes formed by the stand-to-stand edger mill using rolls: FIG. 12 shows the dogbone shape formed by the stand-to-stand edger mill using the grooved rolls shown in FIGS. 9 and 1O, and the conventional flat roll shown in FIG. 7. Figure 13 shows the difference between 8/10 and the edger-roll separation force in the stand-to-stand edger mill with grooved rolls in Figures 9 and 10. A diagram showing the relationship; and FIG.
FIG. 11 is a diagram showing the relationship between B/lo and edger efficiency in the interstand edger mill using grooved rolls in FIGS. 9 and 10; 20: 21: 22: 23.24: 42: 50: 53: Edger Mill Edger Roll Body Flange Hydraulic Actuator Sheet Passing Detector Load Cell

Claims (6)

[Claims] (1) In an edger mill consisting of vertical rolls consisting of grooved rolls installed between strip mill stands to perform width reduction rolling of the strip, the An inter-stand edger mill characterized by having a relatively movable flange section. (2) The inter-stand edger mill according to claim 1, further comprising means for adjusting the interval between the flange portions to a predetermined interval according to the strip thickness. (3) The inter-stand edger mill according to claim 1, further comprising means for setting the interval between the flange portions of the vertical rolls to a value determined based on a predetermined rolling schedule. (4) In the inter-stand edger mill according to claim 1, the distance between the flange portions of the next roll is determined according to the strip thickness obtained from a strip thickness measuring meter provided upstream of the edger mill and close to the edger mill. Edger mill between stands with means to set up. (5) A rolling method using the inter-stand edger mill according to claim 1, wherein the distance between the flange portions is made wider than a predetermined distance until the leading edge of the strip passes through the vertical roll; A rolling method characterized in that the distance between the flanges is returned to the predetermined distance after the leading edge of the flanges passes through the vertical rolls. (6) A rolling method using the inter-stand edger mill according to claim 1, wherein the distance between the flange portions is maintained until the leading edge of the strip is bitten by a horizontal rolling mill installed adjacent to the downstream side of the edger mill. A rolling method characterized in that the intervals between the flanges are made wider than a predetermined interval, and after the leading edge of the strip is bitten by the horizontal rolling mill, the interval between the flanges is returned to the predetermined interval.