JP3109256B2 - Centering method of sheet bar in entrance side guide device for coarse mill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inlet side guide device for a rough mill in a rough rolling mill row of a continuous hot rolling mill.

[0002]

2. Description of the Related Art In a rough rolling mill of a continuous hot rolling mill, at least one pair of side guides facing each other is disposed on both sides of a sheet bar passing path on the entry side of a rough mill having a tandem structure of a horizontal mill and an edger mill. The opening is set at a position 30 to 50 mm wider than the width of the sheet bar (hereinafter referred to as the plate width) to guide the entering sheet bar to the center of the mill and prevent skew. . However, since the sheet is passed while the opening degree of the side guide is set wide so that the seat bar can smoothly enter, it is hard to say that the guiding effect is satisfactory.

[0003] In recent years, a hydraulically driven side guide has been developed in order to improve the sheet passing property.
1st hot strip subcommittee 51-4 “Measures to improve thin material passing property”), when the sheet bar enters the side guide, tighten so as to reduce the gap with the sheet bar side edge, and actively guide. It came to pass through. FIG. 7 shows an example of such a side guide device. In the figure, a sheet bar A advances in the direction of arrow Z, and side guides C are provided on both sides of a sheet bar passageway on the entry side of the horizontal mill H and the edger mill B. This side guide C is driven by a hydraulic cylinder D, and symmetrically with respect to the center of the rolling line (mill center) via a pinion F and a rack beam G in a pinion stand E as shown in FIG. When the guide C opens and closes in a direction orthogonal to the passing direction of the sheet A, the sheet bar A
Centering is possible.

When the centering of the sheet bar A is performed by this side guide device, the gap between the side edge of the sheet bar and the side guide C is reduced before the leading end of the sheet bar A bites into the edger mill B. The guide C is tightened at the same time, and the center of the sheet bar A and the mill center are aligned so as to sandwich the skewed sheet bar A.

On the other hand, separately from this,
No. 4 discloses a side guide device. This means that a movable arm is provided inside the mill side end passageway of the entry side guide, a vertical roller is attached to the inner end of the arm, and the vertical roller and the arm are attached to the arm by a driving device such as a cylinder. It is intended to be moved. According to this side guide device, the tip of the sheet bar is first centered by positively or by moving the vertical roller so as to follow and join the tip of the sheet bar, and then both side guides are tightened. The centering of the entire seat bar can be performed.

[0006] By the way, a feed horizontal roller usually called a table roller is provided below any side guide device, and the rotation of the table roller allows the sheet bar to pass at a predetermined passing speed in a predetermined conveying direction. It is planed.

[0007]

However, in the former of these side guide devices, the required tightening force F required for centering the side guide is determined by the following equation a obtained from the balance of the forces shown in FIG. Given. F = μ · W = F ₁ −F ₂ (a) where μ: coefficient of friction between sheet bar and table roller W: sheet bar weight (plate weight).

Here, if F ₁ in the above formula a is a force for giving a moment to the seat bar, and F ₂ is a reaction force as a rotation center of the seat bar, this force F ₁ is given by the following formula b. . F ₁ = μ · W · L / (2L _G ) (b) where L: sheet bar length (plate length) L _G : side guide length.

[0009] Since here the reaction force F ₂ is the reaction force of the force F ₁ and the opposite, necessary tightening force F of the a-type in side guide apparatus having the structure as shown in FIG. 8 is second force F ₁ For example, even if both side guides are driven by a single hydraulic cylinder, the work itself does not change. In addition, since the required tightening force F is proportional to the plate weight and the plate length and inversely proportional to the side guide length, the device becomes excessively large in order to sufficiently center the long and heavy sheet bar. I will. In addition, a long and heavy sheet bar may not be completely centered especially in the latter stage of the rough mill, and there is a problem that off-center due to oblique biting into an edger mill or a horizontal mill induces bending (camber) of the plate.

On the other hand, in the latter side guide apparatus, for performing the subsequent sheet bar whole centered by side guides while somewhat centering the sheet bar tip by the vertical rolls, because the reaction force F ₂ is no or less side The required tightening force of the guide itself need not be very large. However, there is a problem that the side guide body becomes large and the arm driving device becomes complicated in order to secure the strength of the vertical roll support portion, so that the space is required for the attached device and the equipment cost is increased. Further, in this structure, there is a problem that the roller shaft is greatly worn and it takes time to replace parts.

The present invention has been developed in view of these problems, and has an inlet / outlet side guide for a rough mill capable of achieving a sufficient side guide effect while realizing space and cost savings. It is an object of the present invention to provide a method of centering a seat bar in an apparatus.

[0012]

The present inventors have made intensive studies in view of the above problems, and as a result, have found that the function of the vertical roll in the conventional side guide device is far superior to that of the vertical roll in centering ability. The present invention has been put to practical use, paying attention to replacing the edger mill with a large tightening force.

That is, the centering method of the sheet bar in the entry side guide device for a coarse mill according to the present invention is a method in which an edger mill and a horizontal mill are arranged in parallel with a coarse mill in a coarse rolling mill row of a hot continuous rolling mill. Is rolled from an edger mill to a horizontal mill, and at least on the entry side of the edger mill, on both sides of the sheet bar threading path, at least one pair of side guides are installed facing each other in a rough mill entry side guide device. Until the tip of the seat bar is bitten by the edger mill, the opening of the side guide is widened so that the gap between the side guide and the side edge of the seat bar is increased. The opening of the side guide is tightened so that the gap between the side guide and the side edge of the seat bar becomes small immediately after the side guide is bitten. It is an.

[0014]

According to the centering method of the sheet bar in the side guide device for the rough mill according to the present invention, the gap between the side guide and the side edge of the sheet bar becomes large until the front end of the sheet bar is bitten by the edger mill. In order to widen the opening degree of the side guide, the side edge of the seat bar is smoothly passed to the edge mill without unnecessary rubbing or tightening of the side guide.
Immediately after the front end of the seat bar is bitten by the edger mill, the opening of the side guide is tightened so that the gap between the side guide and the side edge of the seat bar becomes small. At this time, since the front end of the sheet bar is strongly centered and tightened by the edger mill, if the side guide is then tightened, the seat bar rotates around the front end bitten by the edger mill. And centered.

[0015]

FIG. 1 shows an embodiment of a hot rolling mill provided with an inlet side guide device for a rough mill according to the present invention.
In the figure, a sheet bar A is passed from an edger mill B to a horizontal mill H in the direction of arrow Z. Edger Mill B
A pair of side guides 1 and 2 facing each other are installed in parallel with each other on both sides of the sheet bar passage on the entry side. A guide side guide 10 extending outward is provided on the entry sides of the entry side guides 1 and 2 so as to be rotatable toward the entry side, and the entry side end of the guide side guide 10 is provided. The portion is rotatably connected to a frame (not shown) through an elongated hole 11 formed at the end.

The side guides 1 and 2 are driven by two hydraulic cylinders 12 similarly to a conventional side guide device, and are rolled through a pinion 14 and a rack beam 15 in a pinion stand 13 as shown in FIG. By synchronizing the two hydraulic cylinders 12 symmetrically with respect to the line center (mill center) and by moving the two hydraulic cylinders 12 in synchronization with each other, the sheet bars A are moved in a direction orthogonal to the direction in which the sheet bar A passes.

As shown in FIG. 2, a predetermined hydraulic pressure is supplied to the hydraulic cylinder 12 through a servo valve 16, and the hydraulic cylinder 12 is moved to a predetermined position by the servo valve 16. The system can be stopped under pressure. The servo valve 16 is controlled by a servo valve setting signal from the side guide control device 3 as shown in FIG. The side guide control device 3 exchanges signals with the tracking control device 4, and the tracking control device 4 exchanges signals with the higher-order continuous rolling mill control device 5. The continuous rolling mill control device 5 is used for controlling and monitoring the rolling speed of the mill in accordance with the specifications and specifications of the sheet bar A, and the running speed of the mill. The control device 4 obtains the position information of each sheet bar A, monitors the sheet passing speed, and determines the rotation speed of each mill related to the sheet passing speed, the rotation speed of the table roller necessary for conveyance, and the like in the continuous rolling mill. It is for controlling with the control device 5.

A microcomputer (not shown) is provided in the side guide control device 3, and a program shown in a flowchart of FIG. 3 is stored in the microcomputer in advance, and the flow rate of the servo valve 16 is determined based on the program. The opening degree of the side guides 1 and 2 is controlled by controlling the hydraulic pressure. This program will be described in detail with reference to FIG.

First, in step S1, information signals such as the sheet width, the sheet length, the position of the center of gravity, the material specifications, the sheet width after the rolling, the sheet thickness, and the like of the sheet bar A provided from the continuous rolling mill controller 5 are read. Put in. Next, the process proceeds to step S2, and the required tightening force F calculated from the following equation (1) is obtained as the centering force.

F = F ₁ = μ · W · L / (2L _P ) (b) Next, the process proceeds to step S 3, where the tracking information from the tracking control device 4 is read. Next, step S
4 and determine from the tracking information whether the leading end of the sheet bar A has reached the side guides 1 and 2 and if the leading end has reached the side guides 1 and 2 The process proceeds to step S5, and if not, the process proceeds to step S3.

In step S5, both side guides 1,
2 is the plate width obtained in step S1 plus 30 mm
The setting signal of the hydraulic cylinder servo valve 16 is transmitted so that Next, the process proceeds to step S6, where the tracking information from the tracking control device 4 is read again.

Next, the process proceeds to step S7, where it is determined whether or not the leading end of the sheet bar A has bitten into the edger mill B from the tracking information. The process proceeds to S8, and if not, the process proceeds to step S6. In step S8, a setting signal for the hydraulic cylinder servo valve 16 is transmitted so that the opening of both side guides 1 and 2 becomes the plate width plus 15 mm.

Next, the flow shifts to step S9 to read the tracking information from the tracking control device 4 three times. Next, proceeding to step S10, it is determined from the tracking information whether the rear end of the sheet bar A has been released from the edger mill B, and if the rear end has been released from the edger mill B, The process proceeds to step S11, and if not, the process proceeds to step S9.

In the step S11, the setting signal of the hydraulic cylinder servo valve 16 is transmitted so that the two side guides 1 and 2 return to the standby position at the retreat end of the hydraulic cylinder 12, and the program ends. The side guide control device 3 controls the degree of opening of the side guide according to the program, so that the hydraulic cylinder 12 is retracted until the leading end of the seat bar A enters the side guides 1 and 2 as shown in FIG. When the leading end of the sheet bar A enters the side guides 1 and 2, both side guides 1 and 2
Is controlled so that the opening of the sheet bar A becomes plus the plate width, and furthermore, when the tip of the sheet bar A is bitten by the edger mill B, the opening of both side guides 1 and 2 is controlled so that the opening becomes the plate width plus 15 mm. Things.

By performing this control, for example, as shown in FIG. 5, when the sheet bar A is skewed and passed, the edge of the sheet bar A is centered by the edger mill B before the side guides 1 2 pushes the sheet bar A closer to the rear end, whereby the entire sheet bar A is centered on the mill center. At this time, the side guides 1 and 2 merely apply the necessary tightening force F for generating a moment for rotating the entire sheet bar A about the tip end of the sheet bar A that is bitten by the edger mill B. Good. This required tightening force F is the force F shown in the above equation (1).
Since ₁ is comparable, it is not necessary to generate a force F ₂ against the reaction force of the force F ₁ as in the prior art, this required tightening force F
The hydraulic pressure to the hydraulic cylinder 12 for generating the pressure may be small. At the same time, the distance from the center of rotation for generating this moment to the point of application is conventionally known as the side guide length L.
_In contrast to _G , the distance becomes L _P from the edger mill center to the tail end of the side guide, so that a large couple can be generated with a small force. Therefore, a long and heavy sheet bar can be centered with a small oil pressure.

FIG. 6A shows a histogram of the amount of bending at the front and rear ends of 90 sheet bars when centering is performed before the front end of the sheet bar bites into the edger mill as in the prior art. FIG. 6B shows a histogram of the amount of bending at the front and rear end portions of 90 sheet bars when centering is performed according to FIG.

FIG. 6a following the conventional centering method
In the figure, many bends occur on the driven side, the average value of the bend amount is 16.6 mm, and the maximum bend absolute value is 60 mm.
It turns out that it exceeds. On the other hand, in FIG. 6B in which the centering method of the present invention was implemented, it can be seen that the bending amount was approximately 20 mm or less, and a good result was obtained with an average value of 0.5 mm. As described above, according to the centering method of the present invention, by improving the centering effect on the mill entry side, it is possible to absolutely reduce the amount of bending generated in the seat bar.

[0028]

As described above, according to the method of centering the sheet bar in the entry side guide device for the coarse mill of the present invention, the opening degree of the side guide is maintained until the tip of the sheet bar is bitten by the edger mill. So that the sheet bar is smoothly passed through, and immediately after the front end of the sheet bar is bitten by the edger mill, the opening of both side guides is tightened, and the skewed sheet bar is moved to the edger mill. Since the center is rotated by rotating around the center of the tip, the required tightening force of the side guide device is reduced to about one half of that of the conventional one, and the line center is completely centered. It almost completely coincides with the mill center, making it possible to significantly suppress bending and skew.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a rough mill facility using a centering method of a sheet bar in an inlet side guide device for a rough mill according to the present invention.

FIG. 2 is a side view showing a structure of a drive mechanism of the side guide device of FIG. 1 and an arrangement state of a control device.

FIG. 3 is a flowchart illustrating a program stored in a side guide control device 3 of FIG. 2;

FIG. 4 is an explanatory diagram showing a correlation between an opening degree of a side guide and a time performed by the program of FIG. 3;

FIG. 5 is an explanatory diagram showing a balance of forces required for centering of a seat bar performed by the program of FIG. 3;

FIG. 6A is a histogram of a bending amount generated on a sheet bar by a conventional centering method,
(B) is a histogram of the amount of bending generated in the sheet bar by the centering method of the present invention.

FIG. 7 is a schematic plan view of a rough mill facility using a sheet bar centering method in a conventional rough mill entrance side guide device.

FIG. 8 is a side view showing a driving mechanism of the side guide device of FIG. 7;

9 is an explanatory diagram showing a balance of forces required for centering of a seat bar performed by the side guide device of FIG. 7;

[Explanation of symbols]

 1 and 2 are side guides 3 is a side guide control device 4 is a tracking control device 5 is a continuous rolling mill control device 10 is a guide side guide 11 is a long hole 12 is a hydraulic cylinder 13 is a pinion stand 14 is a pinion 15 is a rack beam 16 Is a servo valve A is a seat bar B is an edger mill H is a horizontal mill

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Nobuhiro Tazoe 1 Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Pref. Ishikawajima-Harima Heavy Industries Co., Ltd. Yokohama No. 2 Plant (56) References JP-A-3-264110 (JP, A JP-A-4-84616 (JP, A) JP-A-4-158915 (JP, A) JP-A-5-84506 (JP, A) JP-A-5-293526 (JP, A) 293528 (JP, A) JP-A-2-151314 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21B 39/14 B21B 13/06

Claims (1)

(57) [Claims] An edger mill and a horizontal mill are juxtaposed to a rough mill in a rough rolling mill row of a continuous hot rolling mill, and a sheet bar is rolled from an edger mill to a horizontal mill. In a rough mill entrance side guide device in which a pair of side guides are installed opposite to each other on both sides of the sheet bar passageway, the side guides are used until the tip of the sheet bar is bitten by an edger mill. The opening of the side guide is widened so that the gap between the side guide and the sheet bar is large, and the gap between the side guide and the side edge of the sheet bar immediately after the front end of the sheet bar is bitten by the edger mill. A centering method of a seat bar in an entrance side guide device for a rough mill, wherein an opening of the side guide is tightened to be small.