JP2010099722A - Method and device for controlling pinch roll of winding machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for controlling the pinch roll of a winding machine so as to keep the excellent winding shape of the winding machine by keeping pressing force constant at a part where the plate thickness at the tail end of a steel plate is abruptly changed. <P>SOLUTION: The device for controlling the pinch roll includes: a plate thickness gage 2 for measuring the thickness of a material to be rolled; a material detector 3 and a pinch roll rotation detector 4 for specifying to which position in the longitudinal direction of the measured thickness value of the material corresponds; a thickness recorder 5 for storing or recording the measured thickness value between the set distances to the most-tail end 19 of the material; and a gap setting device 6 which locks on the measured thickness value at the predetermined distance from the most-tail end to define the thickness lock-on value, computes the thickness deviation between the measured thickness value after the thickness lock-on value and the thickness lock-on value, and sets the gap position on the basis of the computed thickness deviation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pinch roll pressing automatic control method and apparatus in a winder, and in particular, in a portion where the change in the thickness of a steel sheet tail end is abrupt, the pressing force is kept constant and the winder is wound. The present invention relates to a control method and apparatus for a winder pinch roll for maintaining a good shape.

  In a winder used conventionally, the material to be rolled is wound with a certain pinch roll pressing force. Generally, the control of the pressing force of the pinch roll of the winder has a mechanism that adjusts the gap between the rolls with high precision by a hydraulic servo, measures the pressing force from the load cell or cylinder pressure detector, and sets the target. The pinch roll gap is controlled so as to be a pressing force (for example, Patent Document 1). By performing such pressing force control, stable pressing force control is possible even when the pressing force is set to be lighter than the weight of the upper pinch roll.

In general, in a hot rolling mill, automatic sheet thickness control is performed so that the material to be rolled has a set sheet thickness, but actually a small thickness deviation occurs in the length direction of the material to be rolled. However, even if there is a slight thickness deviation, the pinch roll pressing force is wound in a constant state, so that the pinch roll back tension is constant. It is possible to take.
Japanese Unexamined Patent Publication No. 64-22416

  However, in a finishing mill, it is common to perform automatic plate thickness control that positively increases the thickness of the rearmost end of the material to be rolled in order to improve the platenability of the rearmost end. For this reason, the pinch roll gap for the over-thickness portion is tightened with respect to the pinch roll gap of the steady portion when the over-thickness portion of the plate thickness at the end passes through the pinch roll. The force is excessive for the stationary part.

  In the above-described pressing force control of the pinch roll, since the control of adjusting the gap of the pinch roll according to the deviation between the target pressing force and the actual pressing force is performed, the plate thickness deviation of the overly thick part at the end is covered. If the deviation is large compared to the plate thickness deviation of the steady part of the rolled material, the fluctuation of the pressing force due to the response delay until the adjustment is completed to the pinch roll gap to be the pressing force state before the over-thickness part Will occur (see FIG. 2A described later).

  In the steady part, the winder and the finishing mill are connected, and the winding tension is sufficiently large against the disturbance of the tension change due to the change in pressing force. In general, winding is performed at a winding tension of 50% or less with respect to the winding tension, and the influence on the material to be rolled is greater than that of the steady portion.

  In addition, since the rearmost end portion of the material to be rolled is not constrained and is easy to meander, if an excessive pressing force is generated when the thickest portion of the rearmost end passes through the pinch roll, the sheet width direction Due to a change in tension distribution of the material, meandering of the tail end of the material to be rolled is induced, and meandering of the portion upstream from the pinch roll is likely to occur.

  Furthermore, when the pinch roll pressing force changes and becomes large, a pinch roll deceleration caused by an increase in mechanical loss occurs, so that a phenomenon that the material to be rolled is doubled before the pinch roll is likely to occur.

  From the phenomenon described above, there has been a problem that a winding deviation or a double dent occurs in the outermost peripheral portion of the wound coil, leading to a quality defect of the product.

  In view of these problems of the prior art, the present invention provides a winder pinch for maintaining a constant pressing force and a good winding shape of the winder at a portion where the change in the thickness of the tail end of the steel plate is abrupt. It is an object to provide a roll control method and apparatus.

  The invention according to claim 1 of the present invention is a winder pinch roll that controls a target pressing force by adjusting a gap of a pinch roll of a winder that winds a material to be rolled that has passed through a finish rolling mill into a coil shape. A plate thickness measurement step for measuring the plate thickness of the material to be rolled and storing or recording a plate thickness measurement value between a set distance to the end of the material to be rolled, and the plate thickness A position tracking step that specifies which position in the longitudinal direction of the material to be rolled is a position tracking step, and locks on a plate thickness measurement value at a predetermined distance from the rearmost end, and a plate thickness lock-on value, A plate thickness lock-on step, a plate thickness measurement value after the plate thickness lock-on value, a plate thickness deviation calculating step for calculating a plate thickness deviation between the plate thickness lock-on value, and a gap based on the plate thickness deviation Gaps for position setting A position setting step, a method of controlling a winder pinch rolls characterized by having a gap position control step of controlling the gap position based on the gap set position.

  In addition, the invention according to claim 2 of the present invention is a winder pinch that controls a target pressing force by adjusting a gap of a pinch roll of a winder that winds a material to be rolled that has passed through a finishing mill into a coil shape. A roll control device for measuring a thickness of the material to be rolled, and a material for specifying which position in the longitudinal direction of the material to be rolled is the thickness measurement value. A detector and a pinch roll rotation detector, a plate thickness recording device for storing or recording a plate thickness measurement value between set distances to the tail end of the material to be rolled, and a plate at a predetermined distance from the tail end The thickness measurement value is locked on to obtain the plate thickness lock on value, and the plate thickness deviation between the plate thickness measurement value after the plate thickness lock on value and the plate thickness lock on value is calculated, and the calculated plate thickness deviation is calculated. And a gap setting device for setting the gap position based on A control device for a winding machine pinch rolls, wherein.

  Since the present invention suppresses a sudden fluctuation in the pressing force of the pinch roll at the rearmost end of the material to be rolled, the meandering of the rearmost end can be prevented and the coil winding state can be improved. it can.

  Also, even for meandering caused by the shape defect at the end, the pinch roll gap is changed before the shape defective part passes through the pinch roll, so that a good winding shape can be maintained. Become.

  The present invention measures and preserves the change in the rolling direction of the thickness of the endmost sheet of the material to be rolled at a certain length interval upstream from the pinch roll, and tracks until it reaches directly below the pinch roll, By changing the gap between the pinch rolls immediately before the sudden change in the plate thickness immediately below the pinch roll occurs, a sudden change in the pressing force of the pinch roll is suppressed.

  By tracking the measured thickness value on the exit side of the finish rolling mill of the material to be rolled, it is possible to predict a change in the thickness of the material to be rolled immediately before the pinch roll. By predicting the change in sheet thickness, adjusting the pinch roll gap in the direction in which the pressing force does not change immediately before the pressing force changes. It becomes possible to minimize the change from the pressing force of the pinch roll before the plate thickness changes at the time of reaching. And since the back tension of the pinch roll is constant and the winding tension is kept constant, the shape of the wound coil can be kept in a good state up to the outermost periphery.

  FIG. 1 is a diagram showing a configuration example of a control device for a winder pinch roll according to the present invention. FIG. 2 is a diagram showing the state of plate thickness measurement (a) and lock-on setting (b). In the figure, 1 is a finishing mill, 2 is a thickness gauge, 3 is a material detector, 4 is a pinch roll rotation detector, 5 is a thickness recording device, 6 is a gap setting device, 7 is a material detector, and 8 is a material detector. Pinch roll, 9 is a winder, 10 is a lifting cylinder, 11 is a position detector, 12 is a push force detector, 13 is a position control device, 14 is tail end longitudinal thickness data, 15 is a cylinder position command value, Reference numeral 16 denotes a plate thickness lock-on value, 17 denotes a plate thickness deviation 1, 18 denotes a plate thickness deviation 2, 19 denotes a tail end, and 20 denotes a distance at which a plate thickness measurement value is stored up to the tail end.

  A plate thickness meter 2 and a material detector 3 are installed on the exit side of the finishing mill 1 to measure the plate thickness in the longitudinal direction of the steel plate and to detect the rearmost end 19. A plate thickness recording device 5 stores or records a plate thickness measurement value at regular intervals between a distance 20 for storing the plate thickness measurement value to the end (takes a length equal to or greater than a lock-on distance described later).

  On the side of the winder 9, the material detector 7, the pressing force detector 12 and the position detector 12, and a pair of upper and lower pinch rolls 8 provided with an elevating cylinder 10 for adjusting the pinch roll gap are tracked from the upstream, and the movement of the steel plate is tracked. A pinch roll rotation detector 4 is arranged.

  The tail end longitudinal direction plate thickness data 14 is sent from the plate thickness recording device 5 to the gap setting device 6, a gap set value based on the plate thickness data is set, and the cylinder position command value based on this gap set value is position controlled. It is sent from the device 13 to the elevating cylinder 10 and adjusted to a pinch roll gap based on the cylinder position command value.

  FIG. 3 is a flowchart showing an example of a processing procedure of the control method of the winder pinch roll according to the present invention.

  First, in Step 11, the thickness is measured by the thickness meter 2 and the measured value is stored or recorded between the set distances to the tail end. In Step 12, the pinch roll rotation detector 4 is used. Track steel plate movement. The stored thickness measurement values at regular intervals in the longitudinal direction are synchronized with the tail end position of the material to be rolled, so that the position from the pinch roll until the end of the material reaches the winder and the winding is completed. Can track.

  Next, at Step 13, when the rearmost end passes through the material detector 7 in the vicinity of the winder, the plate thickness measurement value at a predetermined distance (lock-on distance) from the rearmost end is locked on. The measured thickness value of the locked-on is defined as a thickness lock-on value of 16. In step 14, the thickness deviation is calculated.

  This is because the plate thickness deviation between the plate thickness lock-on value 16 and the plate thickness measurement value after the time when the rearmost end passes through the material detector 7 in the vicinity of the winder (plate thickness measurement value-lock-on value). (See FIG. 2B). It should be noted that the calculation interval of the plate thickness deviation is performed for each distance interval in the longitudinal direction in the plate thickness recording apparatus (for example, plate thickness deviation 1 and plate thickness deviation 2 in FIG. 2B).

  Next, in Step 15, the gap position is set based on the plate thickness deviation. When the calculated plate thickness deviation increases (in the direction in which the plate thickness increases), the pinch roll gap amount is changed in a direction to widen the pinch roll gap. The calculated plate thickness deviation multiplied by the set gain of the normal gap change amount is added to the cylinder position command value 5.

  The pressing force control that adjusts the pinch roll gap so that the pressing force detected by the pressing force detector 12 is the target pressing force, which is performed in the stationary part, memorizes the sheet thickness results, and the pinch roll at the tail end. The control may be continued even while the gap is being changed (during the control of this patent).

  The position where the recorded sheet thickness record is locked on is the distance corresponding to the response time from the start of changing the pinch roll gap to the completion of the pinch roll gap change. It shall be performed at a position before the roll.

  Finally, in Step 16, based on the gap position command value obtained in the previous step, the elevating cylinder is adjusted to perform gap position control in the vicinity of the rearmost end.

  In the present invention, when the pinch roll gap is changed, it is possible to correct that the pressing force is in an inappropriate state even if a measurement error or tracking error of a change in the plate thickness occurs and the gap deviates from the optimum gap to be originally set. it can. In addition, about the measurement of the thickness change part at the end of the material to be rolled here, it is actually measured by a thickness gauge, but due to the change in the rolling state of the final stand of the finishing mill, etc. When the plate thickness change in the longitudinal direction can be estimated, it may be used instead of the plate thickness actual measurement value.

  FIG. 4 is a diagram showing a comparative example between the conventional method and this patent. Fig. 4 (a) shows a conventional method in which a plate thickness deviation of about 300 µm occurs at a portion 15 m from the tail end, and this patent corresponding to (b) shows the plate thickness and the pinch roll gap from above. , And a pinch roll pressing force is applied for comparison.

  In the conventional method shown in FIG. 4 (a), there is a response delay from the position (1) where the thickness deviation starts to increase until the pinch roll gap actually starts to change. The power is excessive. However, in this patent, the change of the pinch roll gap is started early, and the change of the pinch roll pressing force is very small.

It is a figure which shows the structural example of the control apparatus of the winder pinch roll which concerns on this invention. It is a figure which shows the mode of plate | board thickness measurement (a) and lock-on setting (b). It is a flowchart which shows the process sequence example of the control method of the winder pinch roll which concerns on this invention. It is a figure which shows the comparative example of the conventional method and this patent.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Finishing rolling mill 2 Sheet thickness meter 3 Material detector 4 Pinch roll rotation detector 5 Sheet thickness recording device 6 Gap setting device 7 Material detector 8 Pinch roll 9 Winding machine 10 Lifting cylinder 11 Position detector 12 Pressing force detector 13 Position control device 14 Tail end longitudinal direction plate thickness data 15 Cylinder position command value 16 Plate thickness lock-on value 17 Plate thickness deviation 1
18 Thickness deviation 2
19 Maximum end 20 Distance to memorize plate thickness measurement value to the maximum end

Claims (2)

A control method of a winder pinch roll that controls a target pressing force by adjusting a gap of a pinch roll of a winder that winds a material to be rolled through a finish rolling mill into a coil shape,
Measurement of the thickness of the material to be rolled and a plate thickness measurement step for storing or recording the measured value of the thickness between the set distance to the end of the material to be rolled,
A position tracking step for specifying which position in the longitudinal direction of the material to be rolled is the sheet thickness measurement value;
Locking on the plate thickness measurement value at a predetermined distance from the tail end, plate thickness lock-on step to set the plate thickness lock-on value,
A plate thickness deviation calculating step of calculating a plate thickness deviation between the plate thickness lock-on value and the plate thickness measurement value, and the plate thickness lock-on value;
A gap position setting step for setting a gap position based on the plate thickness deviation;
And a gap position control step for controlling the gap position based on the set gap position. A control device for a winder pinch roll that controls the target pressing force by adjusting the gap of the pinch roll of the winder that winds up the material to be rolled that has passed through the finish rolling mill,
A thickness gauge for measuring the thickness of the material to be rolled;
A material detector and a pinch roll rotation detector for specifying which position in the longitudinal direction of the material to be rolled is the sheet thickness measurement value;
A plate thickness recording device for storing or recording a plate thickness measurement value between set distances to the end of the material to be rolled;
The plate thickness measurement value at a predetermined distance from the tail end is locked on to obtain a plate thickness lock on value, and the plate thickness deviation between the plate thickness measurement value after the plate thickness lock on value and the plate thickness lock on value And a gap setting device for setting the gap position based on the calculated thickness deviation, and a control device for a winder pinch roll.

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