JPH0910836A - Method for preventing meander of steel strip tail end and its device - Google Patents

Abstract

PURPOSE: To prevent the occurrence of troubles leading to the stop, etc., of a line by restraining the meander of a coil tail end. CONSTITUTION: A welder is provided on the way of a path line of a steel strip 1 which is paid out of a pay-off reel. A pinchroll 2 is provided at the outlet side of the welder. A housing 2a of the pinchroll 2 is turnable in the wide direction of the steel strip 1 around a supporting point 3 on the path line being by a prescribed distance L away from the pinchroll 2. A plate width gage 4 is arranged at the outlet side of the pinchroll 2. The displacement in the wide direction of the steel strip 1 is detected by the plate width gage 4 and detected signals thereof are supplied to a controller 5. The pinchroll 2 is rotated and displaced by the controller 5 via a hydraulic cylinder 6 based on the displacement in the wide direction of the steel strip 1 detected by the plate width gage 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to the annealing, plating, and
The present invention relates to an equipment on an entrance side of a steel strip processing line for performing a cleaning process, and more particularly, to a method and an apparatus for preventing meandering of a coil tail end paid out from a payoff reel.

[0002]

2. Description of the Related Art In an entrance side equipment of a steel strip processing line, a steel strip coil is unwound from a pay-off reel while being unwound, and the dispensed steel strip is sequentially sent to a predetermined processing equipment. When the payout of the coil is completed, the leading end of the next coil is rewound, the tail end of the preceding coil and the tip of the following coil are welded together by a welder, and the payout of the coil is continued.

A pinch roll is installed on the exit side of the welder, and a steel strip is sandwiched by the pinch roll while the leading end of the coil is passed from the payoff reel to the welder. The required tension is applied to the steel strip on the downstream side of the pinch roll. Then, after the tip of the trailing coil is welded to the tail end of the preceding coil as described above, the pinch roll is opened, and the braking process of the pay-off reel causes the processing steps on the inlet side and the downstream side of the pinch roll. The same tension is applied to the steel strips located at, and the steel strips are conveyed in this state.

[0004]

As described above, the steel strip is conveyed while being pinched by the pinch rolls on the exit side of the welder while the tail end of the preceding coil slips out of the payoff reel and passes through to the welder. However, at this time, the tail end portion of the steel strip on the upstream side of the pinch roll is in a free state where no tension is applied. If the strip is continued in such a tension-free state, the tail end of the steel strip can move freely in the width direction, and the steel strip does not enter at right angles to the roll center line of the pinch roll, which is a so-called meandering phenomenon. Occurs.

When the meandering becomes severe, the steel strip ears are damaged, and the tail end of the coil must be rolled out by the time it reaches the welder, and the strip running must be stopped. is there. Here, the stop of the threading leads to the stop of the entire line. The present invention has been made in view of the above problems, and an object thereof is to suppress the meandering of the tail end of the coil and prevent the occurrence of troubles such as a line stop.

[0006]

In order to achieve the above object, a method of preventing meandering of a steel strip tail end according to the present invention is a pay-off reel for paying out a steel strip coil, and a tail end and a trailing end of a dispensed preceding coil. A welding method for welding the tip of the coil, and a pinch roll which is arranged on the exit side of the welder and which sandwiches the steel strip, and a steel strip tail end treatment method in an inlet side equipment of a steel strip processing line, wherein: The pinch roll is made rotatable in the width direction of the steel strip with a predetermined position on the upstream side or the downstream side of the pass line as a fulcrum with respect to the pinch roll, and the rotatable pinch roll is used to meander the steel strip. It is characterized in that it is rotated accordingly.

Further, in the invention described in claim 2, the value obtained by dividing the distance from the fulcrum to the pinch roll by the plate speed in the configuration described in claim 1 falls within a certain range. It is characterized by doing so. Claim 3
The steel strip tail end meandering prevention device according to the invention described in (1) above is a payoff reel for paying out a steel strip coil, a welder for welding the tail end of the dispensed preceding coil and the tip of the trailing coil, and the output of the welder In the equipment for the entrance side of the steel strip processing line, which is arranged on the side and sandwiches the steel strip, the housing supporting the pinch roll is installed at a predetermined position on the upstream side or downstream side of the pass line relative to the pinch roll. Is configured to be rotatable in the width direction of the steel strip with the fulcrum as a fulcrum, and
An actuator that rotates the housing, a meandering detection unit that is arranged on the entrance side or the exit side of the pinch roll to detect the meandering amount of the steel strip, and a drive signal is supplied to the actuator based on the detection signal by the meandering detection unit. And a controller that operates.

[0008]

The operation of the invention described in claim 1 will be described. The tail end of the coil that slips out of the payoff reel becomes tensionless and meanders in the width direction of the steel strip.By pivotally displacing the pinch roll in accordance with the meandering state, the roll center axis becomes the pass line. Incline from the orthogonal plane. In this way, the meandering of the steel strip is suppressed by tilting the direction orthogonal to the sheet passing direction in the direction of rotation of the pinch rolls, and the amount of meandering is reduced.

Next, the operation of the invention described in claim 2 will be described. If the roll center axis of the pinch roll is tilted by a rotation angle θ with respect to a plane orthogonal to the pass line and the passing speed is V, the pass line is perpendicular to the pass line with a size of V _C = K · V · tan θ. The meandering that occurs in the steel strip is corrected by the minute velocity in the direction. Here, K is a constant determined by the plate width of the steel strip, the tension, the front and rear roll arrangements, and the like.

A problem in suppressing the meandering is that
It is the speed of meandering correction. Now, when the rotation angle θ is set to about 1 to 2 °, θ is sufficiently small, so the tan θ is regarded as θ, and the partial speed V _C is represented by the following equation (1). V _C = K · V · θ (1) Both sides of this equation (1) are divided by the time t to obtain the corrected acceleration α _C.
Then, the following formula is obtained.

Α _C = V _C / t = K · V · (θ / t) (2) Then, when the value of α _C is too large, the steel strip is rapidly corrected and overrun occurs. Control becomes unstable,
A so-called hunting phenomenon occurs. On the contrary, if the value of α _C is too small, a sufficient correction effect cannot be obtained. That is, it is necessary to keep the above α _C within a suitable range in order to obtain an effective meandering correction. From the above formula (2), when the passing speed V is high, (θ / t) Smaller, on the contrary,
When the passing speed V is low, it is necessary to increase (θ / t).

Since the pinch roll rotates about a predetermined fulcrum, when the time t is constant,
In order to reduce the threading speed V, that is, to increase θ, the turning radius, that is, the distance from the fulcrum (rotation center) to the pinch roll is shortened, and conversely, the threading speed V is high, that is, It can be seen that in order to reduce θ, if the turning radius, that is, the distance from the fulcrum (rotation center) to the pinch roll is lengthened, an appropriate meandering correction effect can be obtained.

The invention set forth in claim 2 is made in view of the above, and the relationship between the distance L from the fulcrum to the pinch roll and the strip passing speed V is set within an appropriate range. As a result, an effective meandering correction effect is obtained. That is, the above (L / V) can be regarded as a time constant that gives the rotation angle of the roll, and if it is smaller than the predetermined lower limit value, the meandering correction becomes unstable and causes a hunting phenomenon.
If / V) is larger than the predetermined upper limit value, the correction speed becomes slow and there is a possibility that the correction cannot be performed. Therefore, by keeping the above (L / V) within the predetermined range, the effective meandering correction effect can be obtained. You know you will get.

Here, the reason that the value of (L / V) has a predetermined width is that the constant K in the expression (2) changes depending on the strip width of the steel strip and the like. The appropriate range of the above (L / V) is preferably set to fall within the range of 0.25 seconds to 2.5 seconds. In order to obtain such a value, the pinch from the fulcrum depending on the strip passing speed. By setting the distance to the roll, effective meandering correction is performed.

Here, the lower limit of the above (L / V) is 0.2
5 seconds and the upper limit of 2.5 seconds were confirmed by experiments, etc., considering the width of the target steel strip, equipment, etc., but if it is less than the above lower limit, the meandering correction is unstable. This is because it has been confirmed that hunting occurs and that if the upper limit value is exceeded, the correction speed becomes slow and correction becomes impossible.

Next, the operation of the invention of claim 3 will be described. The meandering detection means detects the meandering amount of the steel strip on the entrance side or the exit side of the pinch roll, and based on the detected value, the pinch roll is rotationally displaced via the actuator, thereby having the above-described action.

[0017]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of an inlet side portion of a steel strip processing line. In this embodiment, as shown in FIG. 1, two payoff reels 7a and 7b are provided, and the payoff reels 7a and 7b
The coils 1a and 1b attached to 7b can be alternately dispensed. The steel strip 1 paid out from each of the pay-off reels 7a and 7b is conveyed along a predetermined path line and sent to a processing section 9 such as a cleaning processing tank.

A welder 8 is provided in the middle of the pass line.
Is installed. This welder 8 is the preceding coil 1
This is a device for connecting the tail end of a and the tip of the following coil 1b by welding. The pinch roll 2 is installed on the exit side of the welder 8. The housing 2a of the pinch roll 2 is, as shown in FIGS.
It is configured to be rotatable in the width direction of the steel strip 1 with a predetermined distance L on the upstream side and with the center position of the pass line as the fulcrum 3.

The housing 2a has a piston rod 6a of a hydraulic cylinder 6 which constitutes an actuator.
Are connected. The hydraulic cylinder 6 is installed such that the axis of the piston rod 6a is oriented in the direction parallel to the pass line. By moving the piston rod 6a forward and backward, the housing 2a, that is, the pinch roll 2 is moved to the fulcrum 3 It is designed to be rotated about a predetermined rotation angle θ in the plate width direction.

The hydraulic cylinder 6 is driven by the hydraulic pressure supplied from the controller 5 as a drive signal. Further, on the exit side of the pinch roll 2, a plate width gauge 4 constituting a meandering detection means is arranged. The strip width meter 4 is capable of detecting the widthwise displacement of the steel strip 1 and supplying the detected signal to the controller 5.

Further, the controller 5 obtains the turning angle θ of the pinch roll 2 based on the displacement of the steel strip 1 in the width direction detected by the plate width gauge 4, and outputs a hydraulic pressure corresponding to the turning angle θ as a drive signal. Can be supplied to the hydraulic cylinder 6.
Next, the operation of the above configuration will be described. The coil 1a is unwound and paid out from one payoff reel 7a, and the steel strip is conveyed along a predetermined path line and sent to the processing unit 9. At this time, the payoff reel 7
The pinch roll 2 is open until the remaining length of the coil 1a of a becomes small.

When the remaining amount of the coil 1a becomes small, the pinch roll 2 starts to sandwich the steel strip 1. As a result, even when the steel strip 1 is not loaded with the brake torque from the payoff reel 7a, a predetermined tension can be applied to the steel strip 1 on the downstream side of the pinch roll 2.

Next, the tail end of the steel strip 1 is attached to the payoff reel 7.
When slipping out from a, the tail end portion is in a tensionless state and meanders in the width direction of the steel strip 1. Then, pinch roll 2
The plate width meter 4 on the rear side detects the widthwise displacement of the steel strip 1, that is, the amount of meandering on the exit side of the pinch roll 2, and a signal corresponding to the amount of meandering is supplied to the controller 5.

The controller 5 corrects the meandering by rotationally displacing the pinch roll 2 via the hydraulic cylinder 6 by an amount corresponding to the deviation of the steel strip from the center of the pass line, which is the amount of meandering. For example, when the steel strip 1 is displaced to the right in the traveling direction (upper side in FIG. 4), as shown in FIG. 4, by rotating the pinch roll 2 to the left in the traveling direction by a predetermined rotation angle, Displacement of the steel strip 1 to the right, that is, meandering is suppressed, and troubles due to meandering such as rolling out of the steel strip 1 from the pinch roll 2 are avoided.

When the tail end of the steel strip 1 conveyed while correcting the meandering as described above is threaded to the welder 8, the tip end of another coil 1b is ejected from the other payoff reel 7b. When the tip of the coil 1b in the subsequent row is threaded up to the welder 8, the tail of the preceding coil 1a and the tip of the following coil 1b are welded by the welder 8. When this welding is completed, the pinch rolls 2 are released from the pinch and the steel strip 1 is continuously discharged.

As described above, in this embodiment, since the pinch roll 2 is rotationally displaced so as to suppress the meandering of the tail end of the steel strip 1, the meandering amount of the tail end of the steel strip 1 becomes small. The trouble caused by meandering such as damage to the edge of the steel strip can be greatly reduced. Actually, the board width is 900-13
Steel strip 1 with a thickness of 00 mm and a thickness of 0.2 to 2.0 mm
It is set to pass through 0 m / min = 0.5 m / sec, the outer diameter of the pinch roll 2 is 200 mm, and the fulcrum 3 from the roll center
By setting the distance L to the (rotation center) to 500 mm and setting (L / V) = 1 second, the steel strip 1
It was confirmed that there was no trouble caused by meandering when passing through the strip after the slip-off from the payoff reels 7a, 7b.

Further, fulcrum 3 from the center of the roll is set so that (L / V) becomes a value smaller than 0.25 seconds.
When the distance L to the (rotation center) was set, it was confirmed that the meandering correction became unstable and a so-called hunting phenomenon occurred. On the contrary, fulcrum 3 from the center of the roll so that (L / V) becomes a value larger than 2.5 seconds.
When the distance L to the (rotation center) was set, it was confirmed that the meandering correction speed became slow and a sufficient correction effect could not be obtained.

Here, in the above embodiment, the above (L / V)
Is set to 1 second, the distance L from the roll center to the fulcrum 3 (rotation center) is set, but according to the plate width of the target steel strip 1 and the roll arrangement state of the equipment, The above L may be set so that the above (L / V) becomes an appropriate value within the range of 0.25 seconds to 2.5 seconds. In the processing line of this embodiment shown in FIG. 1, scrap sheets are connected to the front and rear ends of the coil for 5 to 7 m, and the inlet side portion is long in order to perform the processing for dispensing the scrap sheets. The scrap sheet is also called a leader slip, and has the purpose of minimizing the unrolled portion in the reverse rolling mill.

In the above embodiment, the meandering amount is detected on the outlet side of the pinch roll 2 to perform the feedback control. However, meandering detection means is arranged at the inlet side of the pinch roll 2 to perform the pinch. The rotation control of the roll 2 may be performed.

[0030]

As described above, in the method and apparatus for preventing the meandering of the steel strip tail end of the present invention, the steel strip tail end after slipping out from the payoff reel at the entrance side of the steel strip processing line is provided. Since it is possible to reduce the troubles caused by meandering, it is possible to substantially eliminate problems such as product defects such as damage to the edge of the steel strip and line stoppage.

In particular, by applying the method for preventing the meandering of the tail end of the steel strip described in claim 2, the meandering of the tail end of the steel strip can be effectively suppressed. Further, the method for preventing meandering of the tail end of the steel strip is realized by employing the device described in claim 3, for example.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a steel strip processing line entrance side of an embodiment according to the present invention.

FIG. 2 is a plan view showing a meandering prevention device according to an embodiment of the present invention.

FIG. 3 is a side view showing a pinch roll of an example according to the present invention.

FIG. 4 is a plan view showing a state where a focus roll is rotated.

[Explanation of symbols]

 1 steel strip 1a leading coil 1b trailing coil 2 pinch roll 2a housing 3 fulcrum 4 plate width gauge (meandering detection means) 5 controller 6 hydraulic cylinder (actuator) 7a, 7b payoff reel 8 welder 9 processing unit

Claims (3)

[Claims] 1. A payoff reel for paying out a steel strip coil, a welder for welding the tail end of the dispensed leading coil and the tip of a trailing coil, and a pinch roll arranged on the exit side of the welder for sandwiching the steel strip. In the treatment method of the tail end of the steel strip at the entrance side equipment of the steel strip processing line equipped with,
The pinch roll is rotatable in the width direction of the steel strip around a predetermined position on the upstream or downstream side of the pass line as a fulcrum with respect to the pinch roll, and the rotatable pinch roll is a meander of the steel strip. A method for preventing the meandering of the tail end of a steel strip, which is characterized in that it is rotated in accordance with. 2. The tail end of a steel strip according to claim 1, wherein a value obtained by dividing a distance from the fulcrum to the pinch roll by a strip speed is within a certain range. How to prevent meandering. 3. A payoff reel for paying out a steel strip coil, a welder for welding the tail end of the dispensed leading coil and the tip of a trailing coil, and a pinch roll arranged on the exit side of the welder for sandwiching the steel strip. In the equipment on the entrance side of the steel strip processing line, the housing that pivotally supports the pinch roll can be rotated in the width direction of the steel strip with a predetermined position on the upstream or downstream side of the pinch roll as the fulcrum. And an actuator for rotating the housing, a meandering detection means arranged on the entrance side or the exit side of the pinch roll to detect the meandering amount of the steel strip, and the above-mentioned based on the detection signal by the meandering detection means. A controller for supplying a drive signal to an actuator, and a meandering prevention device for a tail end of a steel strip.