JPS61269918A - Tandem type rolling device - Google Patents

Abstract

PURPOSE:To suppress the thickness fluctuation of a rolling material and to prevent the rupture of the rolling material by controlling precisely the tension of the rolling material between both rolling rolls during the low-speed driving of the rolling rolls of a tandem rolling device. CONSTITUTION:Dumming rolls 10a, 10b are disposed before and behind a detector 4 for the tension of the rolling material between the rolling rolls 2 and 3 in the stage of rolling the rolling material 1 with the tandem rolling device. The former 10a is connected to a proportional integrator 15 and hydraulic cylinder position control device 16 via a hydraulic cylinder 11 for vertical movement as well as a position detector 12 for the roll 10a and a tension detector 13. The integrator 15, the device 16 and the cylinder 11 operate to move vertically the roll 10a and to control adequately the tension on the material 1 by the extra low speed of the roll 2 when the roll 2 slows down to the extra low speed state below the prescribed value. The fluctuation of the rolling thickness of the material 1 and the rupture of the material by the overtension with the roll 3 are thus prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a tandem (continuous) rolling mill, and in particular,
The present invention relates to a tension control device for suppressing variations in thickness of rolled material at very low speeds and when stopped.

[Conventional technology]

A conventional device will be explained based on FIGS. 1 and 2 shown in JP-A No. 55-55204. In the figure, FIG. 1 is a so-called tandem rolling device in which a plurality of rolling rolls are arranged in series. The conceptual diagram shows (1) the rolled material, (2
) is the rolling roll located at the i-th position in the rolling mill, and (3) is the rolling roll located at the (i+1)th position on the downstream side of rolling roll (1).
) is sent to the next rolling roll (not shown) via the rolling roll (3). (4) is a tension detector that detects the tension of the rolled material (1) located between the rolling rolls (2) and (3), and this tension detector (4) transfers the detected value (to Tre) to the comparator ( 5), this comparator (5) calculates the difference between the detected value (to TFB) and the target tension value (TR[F) received from others, and this deviation is received by the proportional integral calculation device (7). The tension correction value is calculated and sent as a correction signal. (8) is a speed adjustment device that adjusts the rotational speed of the motor (9) that drives the rolling roll (2) based on the correction signal of the proportional-integral calculation device (7).

However, the rolled material (1) between the rolling rolls (2) and (3)
) when the tension detector (4) detects the tension, the comparator (5)
The detected value (TFaK) is sent to The comparator (5) receives this detected value (TFB) from another target value (TREE).
The deviation between the Adjust the rotation speed of (9) to adjust the rotation of the rolling roll (2) so that the tension is appropriate.

[Problem that the invention seeks to solve]

However, in the conventional device, when the rotational speed of rolling rolls (2) and (3) is above a predetermined value, the tension control device operates effectively, but when the number of rotations of rolling rolls (2) and (3) is below a predetermined value, the tension control device (1), rolling roll (2)
The rotation speed of the rolling roll (2) is controlled by obtaining a correction signal each time, but when the rotation speed becomes lower than a predetermined value, the responsiveness to this control deteriorates and it becomes impossible to sufficiently follow the high frequency fluctuations that indicate the detected tension. ), (3) When rotating at extremely low speed and stopping with the rolled material (1) caught between them, the speed control accuracy of both deteriorates and abnormal tension occurs in the rolled material (1) between the two. Also, a rolling roll (2).

Problems such as the inability to control the tension occurred after the stop in (3).

Such tension control is illustrated in FIG. 4. In the figure, when the rolling roll (2) is decelerated from time (tl), the downstream rolling roll (3) is also decelerated accordingly, and both of them are They will maintain the same speed and gradually stop in parallel. At this time, the rolling roll (2) is stopped for a period of time (t3) as shown by the solid line in FIG.
), the tension in the rolled material (1) between them becomes greater than when it is flowing down, and rolling rolls (2) and (3) stop with a large potential tension. (Figure □(a)), sometimes rolled material (1)
Sometimes it even broke.

Therefore, by delaying the stopping time of the rolling roll (2) from that of the other rolling roll (3) (t3), the rolling roll (2) is controlled so that the tension between the two rolls is stopped in a state smaller than that during the flow. This was done to deal with the breakage of the rolled material (1) (dashed line in Figure 4).

Even if the tension on the rolled material (1) could be controlled in this way, variations in plate thickness due to variations in tension between the two could not be avoided.

The present invention has been made to solve the above-mentioned problems, and is achieved by accurately controlling the tension between the rolling rolls (2) and (3) during low-speed driving until they come to a stop. The purpose of this is to suppress variations in the thickness of the rolled material and further suppress breakage of the rolled material.

[Means for solving problems]

The present invention detects the tension of the rolled material between the rolling rolls, and provides between the rolling rolls a roll whose contact pressure with the rolled material changes depending on the amount of deviation between the detected value and the target value. It is something.

[Effect]

According to the present invention, even if tension fluctuation occurs in the rolled material between the rolling rolls when the rolling mill is stopped, the rolls change the contact pressure against the rolled material in accordance with the amount of variation, thereby increasing the tension in the rolled material. Since this is controlled, it is possible to suppress the degree of tension change in the rolled material, thereby suppressing plate thickness variation.

〔Example〕

The present invention will be explained below based on the embodiments shown in FIGS. 1 and 2. Note that the same or equivalent parts as in the prior art are given the same reference numerals. In the figure, (10a) and (10b) are damming rolls placed from above the rolled material (1) on the upstream and downstream sides of the tension detector (4), and the upstream damming roll (10a) is equipped with a hydraulic cylinder (11). are connected to each other so that the tension can be adjusted by moving the damming roll (10a) up and down to change the contact pressure against the rolled material (1). (12) is a position detector that detects the position of the damming roll (10a) from the operating state of the hydraulic cylinder (11), and (13) is a horizontal direction of the rolled material (1) based on the position signal detected by the position detector (12). Inclination angle (0+)
(See Figure 2) and tension detector (4)
In response to the detection signal indicating the vertical downward force (F) (see the same figure) detected by the
This is a tension detection device that calculates the tension of the rolled material (1) from the following equation.

(14) is the detected tension (T
Fe) as well as the target tension (TFe)
A comparator (15) receives the signal and calculates the difference between the two, and (15) is a proportional integration device that receives the deviation amount sent from the comparator (14).The signal sent by this proportional integration device (15) is sent to the hydraulic cylinder The position control device (1B) operates to control the position of the hydraulic cylinder (11) relative to the rolled material (1), thereby adjusting the tension of the rolled material (1). In addition, (A) is a proportional integral calculation device (7) and a speed adjustment device (8).
) and between the proportional and integral device (15) and the hydraulic cylinder position control device (IEi).
), (A) are in the OFF state when the rotational speed of the rolling roll (2) is equal to or higher than a predetermined value, and the rolling roll (2) is operated by the proportional-integral calculating device (7) and the speed adjusting device (8) as before.
), the signal from the other proportional-integral device (15) is cut off, and a fixed position signal (17) is sent to the hydraulic cylinder position control device (16) to control the hydraulic cylinder (11). ) to hold the damming roll (10a) in place. However, when the rolling roll (10a) begins to rotate at an extremely low speed below a predetermined value, the relay (A) is turned on and is interposed between the proportional-integral calculation device (7) and the speed adjustment device (8). The signal from the proportional-integral calculation device (7) passes through the holding device (18), and the signal is sent out as a stabilized signal unaffected by external disturbances. (8) The rotational speed of the rolling roll (2) is controlled with high precision via the motor (9). At this time, the fixed position signal (17) is blocked by the relay (A), and instead the signal from the proportional-integral device (15) is transmitted to the hydraulic cylinder position control device (16).
) and damming via the hydraulic cylinder (11).
By changing the contact position of the 10-rule (10a) to the rolled material (1), the tension in the rolled material (1) is controlled according to Equation 0.

As described above, when the rolling roll (2) reaches an ultra-low speed state below a predetermined value, the proportional integral device (15), the hydraulic cylinder position control device (16), and the hydraulic cylinder (11) operate to operate the damming roll (10a). ) by moving up and down the contact position with the rolled material (1), it is possible to maintain the tension at the time of flow without much fluctuation.

At this time, the rolling material (
It is possible to further suppress the tension fluctuations in 1) and, by extension, the plate thickness fluctuations.

Note that the present invention can be used in the entire range of rolling rolls of a rolling mill, and may also be used at speeds below a certain level as shown in FIG. 1(b).

〔Effect of the invention〕

As described above, according to the present invention, it is possible to suppress variations in the thickness of a rolled material produced by a tandem rolling apparatus.

[Brief explanation of drawings]

FIGS. 1(a) and 1(b) are a main part configuration diagram (FIG. 1(a)) of a tandem rolling mill showing an embodiment of the present invention, and an explanatory diagram showing the action of its rolling rolls (FIG. 1(a)). (b)), second
The figure is a conceptual diagram showing the principle of the present invention, Figure 3 is a diagram equivalent to Figure 1 (a) showing a conventional device, and Figure 4 is a diagram equivalent to Figure 1 (b) showing the action of a conventional rolling roll. . In the figure, (1) is a rolled material, (2) and (3) are rolling rolls, (
4) is a tension detector, (10a) is a damming roll (roll), (θl), (
θ2] is the inclination angle, and (T) is the tension. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] It is equipped with a plurality of rolling rolls arranged in series and a tension detector that detects the tension by contacting the rolled material flowing through the rolling rolls, and compares the detected tension value with a reference tension value to determine the rotational speed of the rolling rolls. In a tandem rolling apparatus configured to control the tension of the rolled material by adjusting the tension, a roll is provided at a variable contact position with the rolled material from the opposite side to the tension detector, and the contact position of the roll is The angle of inclination that the rolled material forms with respect to the horizontal direction is determined, and the tension is calculated from this angle of inclination and the detected value of the tension detector, and the tension of the roll is calculated according to the amount of deviation between this calculated value and the reference tension value. 1. A tandem rolling machine characterized by comprising means for variably controlling the contact position of the tandem rolling mill.