KR19980031178A - Winding shape control system and control method of strip end - Google Patents

Abstract

The present invention relates to a winding control system and a control method of a strip installed in a hot rolling mill of a steel mill, and more particularly, in the front of the pinch roll generated due to sudden tension disappearing between the finishing mill and the winding machine during the winding end of the strip. The present invention relates to a winding shape control system and a control method of an end portion of a strip which is improved to effectively prevent the occurrence of loops of strips and strip overlap phenomenon through stepwise pressure control of a pinch roll.

The present invention is the loop of the strip (S) in the front of the pinch roll 130 and the strip (S) overlapping phenomenon occurs due to the sudden loss of tension between the finishing mill and the winding machine during the winding end of the strip (S) By effectively preventing the pinch roll 130 through the step-by-step pressure control it is possible to obtain a finished product of good quality.

Description

Winding shape control system and control method of strip end part.

The present invention relates to a winding control system and a control method of a strip installed in a hot rolling mill of a steel mill, and more particularly, in the front of the pinch roll generated due to sudden tension dissipation between the filament rolling mill and the winder during the end end winding operation of the strip. The present invention relates to a winding shape control system and a control method of a strip end portion which is improved to effectively prevent the occurrence of loops of strips and strip overlapping through stepwise pressure control of a pinch roll.

In general, the winding shape control method performed in the conventional strip winding is carried out through the winding shape control system 100 and the control method shown in FIGS. As shown in FIG. 1, the pinch roll pressure control calculation value is input to the pinch roll pressure control unit 110 for pressure control of the pinch roll drawing the strip to the front side, and the pinch roll pressure control unit 110 It provides a signal to the control computer 120, the pinch roll interval correction unit 140 is connected to the control computer 120, the device 150 for detecting the front and rear ends of the strip (S) is connected to each other Will provide a positive signal. Accordingly, the control computer 120 adjusts the pressure and the gap between the pinch roll 130 using the servovalve 155 and the pinch roll gap and the pressure control cylinder 160 based on the signals of these devices. .

Each device-specific control step in the winding shape control system 100 of such a strip end is as shown in FIG. First, before the tip of the strip S arrives at the pinch roll 130, the pinch roll 130 is set at an interval according to the thickness of the strip S. In this process, the step 200 of inputting the pinch roll 130 interval and the pressure calculation value to the pinch roll pressure control unit 110 is performed. In this step 200, the pinch roll 130 interval value is as shown in Equation (1) below, the pinch roll 130 pressure value is as shown in Equation (2) below.

Pinch Roll Spacing = Strip (S) Thickness-(Strip (S) Thickness × 0.1) ----- Equation (1)

Where μ is the friction coefficient (0.2 to 0.3), σ is the specific tension of the strip S, t is the strip S thickness, and ω is the strip S width.

Then, in the next step 210, the pinch roll spacing control by the pinch roll spacing correction unit 140 is made, the pinch roll 130 when the front end of the strip (S) bites the pinch roll 130 The actual pressure is applied, and the value is compared with the pinch roll pressure calculation value of the above formula, and the difference is calculated at intervals and control is performed by the interval. In the next step 220, the strip (S) position tracking operation to determine whether the strip (S) between the pinch roll 130 is made by the front and rear end position determination portion 150 of the strip (S). If the answer is no in this step, the process proceeds to step 210, and if the answer is yes, the pinch roll pressure control unit 110 controls the pinch roll pressure control unit 110 in step 230. Then, in the next step 240, the strip S position tracking operation for whether the strip S is between the pinch rolls 130 is performed again by the front and rear end position determination unit 150, and if this step ( In step 240, if the answer is no, the process proceeds to step 250. If the answer is yes, the pinch roll interval control by the pinch roll spacing controller 140 is performed, and the winding shape control of the end of the strip S is performed. Will be completed.

However, the winding shape control method of the conventional end of the strip (S) as described above is a method using the same pressure calculation formula (fixed pinch roll pressure value), such as the formula (2) from the leading end to the end of the strip (S) Control is performed. Therefore, the conventional control method according to the strip (S) by the tension of the strip (S) at the time when the end of the strip (S) passes through the finishing mill 170, as if pulling the rubber band and then release one side of the strip (such as natural phenomenon) S) is bounced toward the pinch roll 130 (see dashed line in FIG. 1), and when the loop S of the strip S is generated, the strip S overlaps the pinch roll 130 so that the mandrel 180 and the pinch roll This leads to a wound shape failure due to the impossibility of tension control between 130. Therefore, the surface quality of the strips (S) and the fall of the error rate is to cause problems.

In order to solve the above problems, the present invention provides a pinch roll for stripping and strip overlapping on the front of the pinch roll caused by sudden tension disappearing between the finishing mill and the winder during the winding of the end of the strip. It is an object of the present invention to provide a winding shape control system and a control method of the strip end portion which are improved to effectively prevent the pressure through the stepwise pressure control.

1 is a block diagram showing a winding shape control system of the end of the strip according to the prior art,

2 is a flow chart showing a winding shape control method of a strip end part using a conventional system step by step,

3 is a configuration diagram showing a winding shape control system of a strip end portion according to the present invention;

Figure 4 is a flow chart showing a winding shape control method of the strip end portion according to the present invention,

5 is an explanatory diagram showing a telescope winding failure generated in a general winding strip coil;

Explanation of symbols on the main parts of the drawings

10 ..... pressure calculation setting part 12 ..... pressure control part

14 ..... Interval Correction 16 ..... Position Detection

20 ..... Control computer 30 ..... Pressure control by strip position

130 .... Pinch Roll S ....... Strip

In order to achieve the above object, the present invention, in the device for controlling the winding shape of the strip end portion, the pressure control value setting unit for calculating the pinch roll pressure control value for the pressure control of the pinch roll drawing the strip to the front side ; A pinch roll pressure control unit connected to the pressure control value setting unit to perform pinch roll pressure control based on the pinch roll pressure control value; A gap adjusting unit for adjusting and adjusting the gap between the pinch rolls; A position detector for detecting the front and rear ends of the strip; A control computer for adjusting the pressure and spacing between the pinch rolls using a servovalve and a pinch roll spacing and a pressure control cylinder based on a signal obtained by being electrically connected to the pressure control section, the spacing adjuster, and the position adjusting section. And, between the pressure control value setting unit and the pressure control unit by providing a winding shape control system of the strip end portion, characterized in that the pressure adjustment unit for each strip position to sequentially lower the pressure set value of the pinch roll for each position of the strip is included. All.

In addition, the present invention is a method for sequentially controlling the winding shape of the end of the strip, the pinch roll pressure calculation value setting unit in the pinch roll interval and pressure calculation value is calculated as shown in the following equation (1) and (2)

Pinch Roll Spacing = Strip (S) Thickness-(Strip (S) Thickness × 0.1) ------ Equation (1)

Where μ is the coefficient of friction (0.2 to 0.3), σ is the specific tension of the strip S, t is the strip S thickness, and ω is the strip S width;

Performing pinch roll spacing control by a pinch roll spacing controller according to the pinch roll calculated value; A strip position tracking operation of whether the strip is between the pinch rolls, by the front and rear end position detection unit; If the response in the step is YES, the pinch roll pressure control by the pinch roll pressure control unit is made; Determining whether an intermediate portion of the strip S is between the pinch rolls; If the response in the above step is YES, the first pinch roll pressure control by the pinch roll pressure control unit is performed as shown in Equation (3) below.

Determining whether the end of the strip is between the pinch rolls; If the response is YES in the above step, the secondary pinch roll pressure control by the pinch roll pressure control unit is performed as shown in Equation (4) below.

A strip position discrimination operation of whether the strip is between the pinch rolls is performed by the strip front and rear end position detection unit; If the response is no in the step, the pinch roll gap control by the pinch roll gap control unit is performed; by providing a winding shape control method of the end of the strip characterized in that it comprises a.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

The winding shape control system 1 of the end of the strip according to the present invention calculates the pinch roll pressure control value for the pressure control of the pinch roll 130 which pulls the strip S forward, as shown in FIG. And a pinch roll pressure control unit 12 connected to the pressure control value setting unit 10 to perform pinch roll pressure control based on the pinch roll pressure control value. In addition, there is provided a gap adjusting unit 14 for correcting and adjusting the interval between the pinch roll 130 and the position detecting unit 16 for detecting the front and rear ends of the strip (S), these pressure control unit 12, gap adjustment The control unit 20 is electrically connected to the unit 14 and the position adjusting unit 14 to receive signals, respectively, and the control computer 20 receives the servovalve 155 and the pinch roll based on these signals. It is configured to adjust the pressure and the gap between the pinch roll 130 by using the gap and the pressure control cylinder 160.

Then, between the pressure control value setting unit 10 and the pressure control unit 12 is provided with a strip position pressure adjusting unit 30 for sequentially lowering the pressure set value of the pinch roll for each position of the strip, the strip position Star pressure control unit 30,

① The tip area of the strip: At the distance from the tip of the strip S to the mandrel 180 to the point where the take-up roll is open, the pressure control value of the pinch roll 130 is expressed by the following equation (2). ),

Where μ is the friction coefficient (0.2 to 0.3), σ is the specific tension of the strip S, t is the strip S thickness, and ω is the strip S width.

② Middle part area of strip S: In the middle area between the leading end and tail end of strip S, the pressure control value of pinch roll 130 is adjusted by the following equation (3),

③ The trailing edge region of the strip S: The pinch roll 130 in the region from the non-passing portion of the pinch roll 130 to the trailing edge of the strip S at the point where the trailing edge of the strip S passes through the finishing mill 170. It is configured to adjust the pressure control value of) by the following equation (4).

The winding shape control method 50 of the strip S end part using the winding shape control system 1 of the strip S end part of this invention comprised as mentioned above is as follows. As shown in FIG. 4, first, the punch roll pressure calculation value setting unit 10 calculates the interval between the pinch roll 130 and the pressure calculation value as shown in Equations (1) and (2) below. 51).

Pinch Roll Spacing = Strip (S) Thickness-(Strip (S) Thickness × 0.1) ---- Formula (1)

Where μ is the friction coefficient (0.2 to 0.3), σ is the specific tension of the strip S, t is the strip S thickness, and ω is the strip S width. Here, the step 51 is the pinch roll 130, the interval is set according to the thickness of the strip (S) before the tip of the strip (S) to reach the pinch roll 130, the equation of step 51 Step 52 in which the pinch roll 130 interval control is performed by the pinch roll spacing controller 12 is executed in accordance with the calculated pinch roll 130 (1).

Then, step 54 is performed in which the strip S position tracking operation is performed by the strip front and rear end position detecting unit 16 as to whether the strip S is between the pinch rolls 130, and the step 54 In step 56, the pinch roll pressure control unit 12 controls the pinch roll 130, and if the response is no in step 54, the process returns to step 52. The pinch roll 130 interval control is made again.

Then, step 58 is performed to determine whether the middle portion of the strip S is between the pinch rolls 130, and if the response is yes in the step 58, the pinch roll pressure control unit 12 Primary pinch roll 130 pressure control by the following equation (3)

Step 60 is made. In addition, if the answer is no in step 58, the process proceeds to step 56, whereby pinch roll 130 pressure control is performed again.

Then, step 62 is performed in which a determination is made as to whether the end of the strip S is between the pinch rolls 130, and if the response is yes in the step 62, the pinch roll pressure control part 12 The second pinch roll 130 pressure control by the step (64) is made as shown in equation (4) below

Is executed. In addition, if the answer is no in step 62, the process proceeds to step 60, where the first pressure control of the pinch roll 130 using Equation (3) is made again.

Next, a step 66 is performed in which the strip S position discrimination operation on whether the strip S is between the pinch rolls 130 is performed by the strip S front and rear end position detection unit 16 again. If the answer is no in step 66, step 68 where pinch roll 130 spacing control is performed by pinch roll spacing controller 12 is executed to end step 70, and if step 66 If the answer is yes, the process proceeds to the step 64 to achieve the secondary pressure control of the pinch roll 130 using Equation (4).

As can be seen from the above, according to the present invention by applying the pressure calculation value of the pinch roll 130 in accordance with the length of each position of the strip (S) by the phenomenon such as a rubber band bounces when winding the end of the strip (S) This does not occur, and as shown by the dotted line in FIG. 3, the loop phenomenon of the strip S is prevented, and the strip S can stably enter the pinch roll 130.

In order to examine the effects of the present invention in more detail, the experiments were conducted in the conventional manner and in the manner of the present invention for general steel and stainless steel, and the results are shown in Table 1 below.

TABLE 1

According to the present invention as described above, it is possible to obtain a winding coil of good quality because the telescope winding failure phenomenon as shown in FIG.

Therefore, according to the present invention, the loop of the strip S on the front of the pinch roll 130 and the strip S generated by the sudden tension dissipation between the finishing mill and the winder during the end of the strip S winding operation. By effectively preventing the stacking phenomenon through the stepwise pressure control of the pinch roll 130, the finished product of good quality can be obtained.

Claims (5)

In the device for controlling the winding shape of the end of the strip (S), the pressure control value setting unit for calculating the pressure control value of the pinch roll 130 for the pressure control of the pinch roll 130 drawing the strip (S) to the front side 10; A pinch roll pressure control unit 12 connected to the pressure control value setting unit 10 to perform pinch roll 130 pressure control based on the pinch roll 130 pressure control value; A gap adjusting unit 14 for correcting the gap between the pinch rolls 130; A position detecting unit 16 for detecting the front and rear ends of the strip S; The servo controller 155 and the pinch roll gap and the pressure control cylinder 160 are based on the signals obtained by being electrically connected to the pressure controller 12, the gap controller 14, and the position controller 14. And a control computer 20 for adjusting the pressure and spacing between the pinch rolls 130, and between the pressure control value setting unit 10 and the pressure control unit 12 for each position of the strip S. Winding shape control system of the lower end of the strip, characterized in that it further includes a pressure adjusting unit 30 for each position of the strip (S) to sequentially lower the pressure set value of 130). According to claim 1, wherein the pressure adjustment unit 30 for each position of the strip is the distance from the leading end of the strip to the time when the leading end of the strip (S) starts to be wound on the mandrel 180 to open the winding roll (Open) In the pressure control value of the pinch roll 130 is adjusted by the following formula (2), Here, μ is the coefficient of friction (0.2 ~ 0.3), σ is the specific tension of the strip (S), t is the strip (S) thickness, ω is the winding shape of the end of the strip, characterized in that the width of the strip (S) Control system. According to claim 1, wherein the strip position-specific pressure control unit 30 is the pressure control value of the pinch roll 130 in the middle region between the leading end and the trailing end of the strip (S) in the middle region of the strip (S) below With formula (3) Winding shape control system of the end of the strip characterized in that the adjustment. According to claim 1, wherein the pressure position control unit 30 for each strip position is not passed through the pinch roll 130 at the time when the end portion of the strip (S) passes through the finishing mill 170 in the end portion region of the strip (S). In the area from the part to the end of the strip S, the pressure control value of the pinch roll 130 is expressed by the following equation (4). Winding shape control system, characterized in that configured to adjust. In the method for sequentially controlling the winding shape of the end of the strip, in the pinch roll pressure calculation value setting unit, the pinch roll interval and the pressure calculation value are calculated as in Equations (1) and (2) below (51). Pinch Roll Spacing = Strip (S) Thickness-(Strip (S) Thickness × 0.1) ------ Equation (1) Where μ is the coefficient of friction (0.2 to 0.3), σ is the specific tension of the strip S, t is the strip S thickness, and ω is the strip S width; A pinch roll gap control by a pinch roll gap controller (52) according to the pinch roll calculated value (52); A step 54 in which the strip position tracking operation for whether the strip is between the pinch rolls is made by the strip front and rear position detecting units; (56) a pinch roll pressure control by the pinch roll pressure control unit is made if the response is yes in the above step; Judging whether a middle portion of the strip S is between the pinch rolls (58); If the response is YES in the above step, the first pinch roll pressure control by the pinch roll pressure control unit is performed as in Equation (3) below (60). Judging whether the end of the strip is between the pinch rolls (62); If the response is yes in the above step, the second pinch roll pressure control by the pinch roll pressure control unit is performed as shown in Equation (4) below (64). A step 66 in which the strip position discrimination operation of whether the strip is between the pinch rolls is performed again by the strip front and rear position detection units; And if the answer is no in the step, performing a pinch roll spacing control by a pinch roll spacing controller (68).