JP4618154B2 - Strip centering method and apparatus - Google Patents

Description

  The present invention relates to a strip centering method and apparatus in a strip passage line, and more particularly to a strip centering method and apparatus for preventing a trim removal trouble in a side trimmer facility.

  In a steel strip processing line, for example, a steel pickling line, in order to make the width of the pickled steel strip (hereinafter referred to as "strip") constant according to the demand of the customer and the next process, the winding tension Cut both ends with side trimmer equipment before reel.

  In the steel pickling line, a steering roll facility is provided for each point, and CPC control (center position control) is performed based on information from the sensor that detects the position in the width direction of the strip. Doing, centering the strip and preventing rollout. This CPC control uses feedback control as a control method and is mainly based only on proportional control.

  Among the CPC controls in each equipment of the steel strip pickling line, in particular, the CPC control immediately before the side trimmer equipment is higher than the CPC control in other equipment from the viewpoint of preventing trim removal. Sex is required. In the description here, the steering roll immediately before the side trimmer facility is referred to as a “target stage”.

  Various techniques have been proposed so far for high-precision strip centering technology in front of the side trimmer equipment. For example, Patent Literature 1 discloses a technique called “steel strip centering device”. This technology is a combination of a side guide device and two steering roll devices. Each of the two steering roll devices is provided with a strip position sensor on the exit side, and each steering roll device has a strip center. It is to be controlled independently. Moreover, it is described that it is necessary to keep a sufficient distance between the two steering roll devices, and an idle roll is arranged in the middle.

Patent Document 2 discloses a technique referred to as “a steel plate passing method in a continuous line”. In this technique, the target of the strip position is changed periodically and reciprocated in synchronization with the front and rear steering roll devices.
JP-A-9-86739 JP 2001-278516 A

  However, in the technique described in Patent Document 1, in the CPC control of the steering roll one stage upstream from the target stage, the strip can be centered in the vicinity of the center position of the steering roll. There is a steady state where the steering roll position deviates from the center position (for example, a position near the steering operation range limit such as 60 mm eccentricity) (this state is hereinafter referred to as a steady state). FIG. 2 is a diagram schematically illustrating a problem caused by the conventional technique (Patent Document 1).

  No. N steering roll (target stage = N) and No. (N-1) steering roll (one stage upstream from the target stage) are shown on the left and right. Manipulation amount] The time change of the steering roll position and the positional relationship between the roll and the strip are shown.

  FIG. 2 shows a steady state at a specific plate width, and the No. (N-1) steering roll itself is centered in the vicinity of the center to pass the plate, but the No. N steering roll ( Since the plate meanders to the OP side (working side of the rolling stand) until the target stage), the steering roll position of the No. N steering roll is moved from the center position by the CPC control of the No. N steering roll. It is in a state in which the centering of the plate is finally steadily secured by eccentricity of 60 mm.

  The eccentricity of the steering roll position of 60 mm is close to the limit of the operable range of the steering roll, and when it becomes an unsteady state deviating from this steady state (for example, when acceleration / deceleration of the line speed is performed) Etc.), and if the strip meanders, the steering roll position control equipment restriction (exceeds the controllable range) from the previous steady state, and the prescribed satisfactory control cannot be performed, causing trouble in trim removal. May occur.

  When compared to driving a car, the car is moving straight (steady state) with the steering wheel turned (steering), and even if you try to turn the steering wheel at the corner in this state, it is more than that. It's like being unable to turn the handle and crashing.

  The steady state as described above is that the strip itself meanders between the (N-1) stage steering roll device and the N stage (target stage) steering roll device. This is attributed to the installation state and wear state of each steering roll. In such a state, if a sufficient distance is taken between the two steering roll devices by the technique described in Patent Document 1, the opposite effect is obtained. Moreover, it has been empirically found that this meander becomes more prominent as the width of the material being passed is narrower.

  The technique described in Patent Document 2 is originally intended to prevent roll wear. In order to make roll wear uniform, the target of the strip position is changed periodically to synchronize with the front and rear steering roll devices. Therefore, the strip centering with high accuracy that can prevent the trim removal immediately before the side trimmer equipment is not achieved.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a strip centering method and apparatus that achieves more accurate strip centering before a side trimmer facility.

The above problems can be solved by the following invention.
[1] A strip centering method in which CPC control (center position control) is performed by a plurality of steering rolls arranged in a strip passing plate line that continuously welds a plurality of strips. ,
To set the steering roll position of the steering roll set as the target stage within a predetermined range,
Based on the relationship between the strip width and threading speed obtained in advance and the correction amount of the strip target position,
The strip target position of the steering roll upstream of the steering roll set as the target stage is set for each of the plurality of strips to be passed until the strip passes through the upstream steering roll. A method for centering a strip.

[2] In the strip centering method according to [1] above ,
Based on the steering roll CPC control (center position control) result set as the target stage ,
A strip centering method comprising sequentially updating a relation between a strip width and a plate passing speed of the strip and a correction amount of a strip target position .

[3] A strip centering device having a CPC control (center position control) device on each of a plurality of steering rolls arranged in a strip passing plate line that continuously welds a plurality of strips. And
To set the steering roll position of the steering roll set as the target stage within a predetermined range,
Based on the relationship between the strip width and threading speed obtained in advance and the correction amount of the strip target position,
Control means for setting the strip target position of the steering roll upstream of the steering roll set as the target stage for each of the plurality of strips to be passed through until the strip passes the upstream steering roll. A strip centering device characterized by the above.

  In the present invention, the CPC control with the steering roll immediately before the side trimmer equipment can be controlled within the equipment restrictions, and it is possible to prevent a trim detachment trouble in the side trimmer equipment and contribute to productivity.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is a diagram illustrating an example of an apparatus outline of pickling line equipment. In the figure, 1 is a strip, 2 is a payoff reel, 3 is a welder, 4 is a skin pass mill, 5 is a pickling tank, 6 is a rinse, 7 is a dryer, 8 is a side trimmer, 9 is a laboratory, 10 is a shear, 11 Reference numerals 19 to 19 denote No. 1 to No. 9 steering rolls, and 20 denotes a tension reel.

  The strip 1 paid out by the payoff reel 2 for rewinding the coil is welded by the welder 3 so as to continuously pass the line. In order to store the strip 1 which is fed into the pickling tank 5 without stopping, the welded strip 1 can be stored in No. 1 through No. 4 steering roll (11-14), etc.

  Then, after temper rolling to improve mechanical properties by the skin pass mill 4, iron oxide (scale) on the surface of the strip is removed with an acid solution in the tank. Then, the remaining acid on the strip surface after pickling is rinsed with a rinse 6 and a dryer 7 and dried.

  On the exit side, in order to prevent the strip 1 from stopping even during operations such as carrying out the coil on the exit side, end plate processing, trimming width change, etc., the No. 5 to No. 9 steering rolls (15 to 19) It goes through the output side coil storage device comprised by the above.

  Then, in the side trimmer 8, as described above, both ears of the strip 1 are continuously cut to a specified width. In the inspection room 9, the strip 1 is inspected for wrinkles, and the strip 1 is cut by the shear 10 when the length becomes a predetermined length. The cut strip 1 is finally wound in a coil shape by the tension reel 20.

  The above is the main process of the pickling line, but this is only an example, and other processes may be included. In the example of FIG. 1, the “target stage” that is the steering roll immediately before the side trimmer equipment is the No. 9 steering roll 19, and the No. 8 steering roll 18 to the No. 1 steering roll 11 are sequentially upstream. A steering roll is installed.

  In the present invention, the meandering of the strip being conveyed between the (N−n) -th stage steering roll device “n-stage upstream from the target stage” and the “target-stage” N-th stage steering roll apparatus is considered. Thus, the CPC controllability at the target stage is ensured by positively correcting in advance the target value of the strip position from the target stage to the steering roll device upstream of the n stage. For example, when n = 1 in the example of FIG. 1, the No. (N−n) steering roll n stages upstream from the target stage is the No. 8 steering roll 18.

  The present invention has the following configuration. First, (1) the strip target position in the CPC control of the steering roll n stages upstream from the target stage is positively corrected so that the steering roll position of the target stage CPC control is within a predetermined range. FIG. 3 is a diagram schematically illustrating the present invention. As shown in the prior art of FIG. 2, the state of the No. (Nn) steering roll and the No. N steering roll (target stage) is shown. These are shown separately on the left and right, and the time variation of the [control amount] strip position and [operation amount] steering roll position from the top, and the positional relationship between the roll and strip are shown.

  No. (N-n) [Control amount] Steering roll [Zero] The target of the strip position is positively set to Z instead of 0, and to the DR side (rolling stand drive motor motor installation side) as much as possible Try to pass through. By doing so, the No. N steering roll position in the case where the No. N steering roll CPC control due to the meandering of the plate to the OP side up to the No. N steering roll (target stage) is not used. As a result, even if CPC control is applied, it is only necessary to move the roll slightly to the DR side. As a result, there is a margin up to the limit of the operable range of the steering roll compared to the conventional technology of FIG. 2, and even if a disturbance or the like occurs, it does not affect the control facility restrictions (exceeding the controllable range) of the steering roll position. Predetermined satisfactory control can be performed, and the trouble of trim removal does not occur.

  (2) No. The correction value of the strip target position of the steering roll of (N−n) is variable depending on the plate width of the plate material from the above knowledge. It is also variable depending on the plate passing speed. Furthermore, the correction value is restricted from the viewpoint of securing the shape of the strip so that the steering roll does not roll out. This is a specific method of determining the correction value of the strip target position described in (1) above, and will be described in detail later.

  (3) Further, the correction value is learned and updated so as to always keep an optimum state and to cope with a change with time due to the use state of the equipment. This will also be described later.

As described above, the conventional technology controls each steering roll independently. In the present invention, however, the steering rolls are controlled in a coordinated manner.
As described above, in this embodiment, the pickling line has been described as an example. However, the pickling line is not limited to the pickling line, and may be a strip passing plate line such as a continuous annealing line or a plating processing line in which a steering device is similarly arranged. Needless to say, this is applicable.

Example 1 (No. (Nn) stage steering roll CPC control) of the present invention will be described below (see FIG. 4).
First, a “correction amount table corresponding to the strip width” (hereinafter referred to as a correction amount table) is provided in advance in the overall controller (control means) of the steering roll device. Further, several types of this table are set and stored for each speed region.

  The general controller then inputs the strip width and speed information of the strip that is currently being passed from the computer that manages the line, and based on that information, calculates the necessary correction amount from the “correction amount table” described above. It is obtained in advance, and by the timing of passing each roll, No. It is transmitted to the CPC controller of the (N−n) stage steering roll and set. At this time, if the necessary correction amount is larger than the predetermined upper limit value, the upper limit value is transmitted so as to limit the upper limit of the correction value.

  Then, no. The CPC control device for the (N−n) -th stage steering roll adds the transmitted correction amount to the target value (originally 0) of the strip position and controls it.

Embodiment 2 of the present invention (learning function of correction amount table based on CPC control results of target stage No. N stage) will be described below (see FIGS. 5 and 6).
The overall controller of the steering roll device is the target stage number. The correction amount table is updated as needed based on the CPC control result of the N steering rolls.
As a method of this update, for example, when a certain speed V continues for a certain time t or longer, the average value X of the steering roll position of the target stage and the average value Y of the strip position of the target stage at that time Then, a correction amount Z (Z = XY) is obtained (FIG. 5), and a new correction amount Z1 is obtained from the current correction amount of the plate width as shown in the following equation (FIG. 6).
New correction amount Z1 = α × correction amount Z + (1−α) × current correction amount Z0
Where α: Update coefficient (0 to 1)
The new correction amount Z1 obtained in this way is replaced with the current correction amount Z0 at the corresponding position in the correction amount table, so that the correction amount table is updated and the optimum state is always maintained.

It is a figure which shows an example of the apparatus outline | summary of a pickling line installation. It is a figure which illustrates the problem by a prior art (patent document 1) typically. It is a figure which illustrates this invention typically. It is a figure explaining Example 1 of the present invention. It is a figure explaining Example 2 (the 1) of this invention. It is a figure explaining Example 2 (the 2) of this invention.

Explanation of symbols

1 Strip 2 Payoff Reel 3 Welder 4 Skin Pass Mill 5 Pickling Tank 6 Rinse 7 Dryer 8 Side Trimmer 9 Inspection Room 10 Shear 11 No.1 Steering Roll 12 No.2 Steering Roll 13 No.3 Steering Roll 14 No.4 Steering Roll 15 No. 5 Steering roll 16 No. 6 Steering roll 17 No. 7 Steering roll 18 No. 8 Steering roll 19 No. 9 Steering roll 20 Tension reel

Claims (3)

A strip centering method for performing CPC control (center position control) on each of a plurality of steering rolls arranged in a strip passing plate line that welds and continuously passes a plurality of strips,
To set the steering roll position of the steering roll set as the target stage within a predetermined range,
Based on the relationship between the strip width and threading speed obtained in advance and the correction amount of the strip target position,
The strip target position of the steering roll upstream of the steering roll set as the target stage is set for each of the plurality of strips to be passed until the strip passes through the upstream steering roll. A method for centering a strip. The strip centering method according to claim 1,
Based on the steering roll CPC control (center position control) result set as the target stage,
A strip centering method comprising sequentially updating a relation between a strip width and a plate passing speed of the strip and a correction amount of a strip target position. A strip centering device having a CPC control (center position control) device on each of a plurality of steering rolls arranged in a strip passing plate line that welds and continuously passes a plurality of strips,
To set the steering roll position of the steering roll set as the target stage within a predetermined range,
Based on the relationship between the strip width and threading speed obtained in advance and the correction amount of the strip target position,
Control means for setting the strip target position of the steering roll upstream of the steering roll set as the target stage for each of the plurality of strips to be passed through until the strip passes the upstream steering roll. A strip centering device characterized by the above.