JPH0422511A - Method and device for detecting slip between strip and mandrel on hot rolling winding device - Google Patents

Abstract

PURPOSE:To exatly detect the slip of the strip against the mandrel and to improve the quality control for the strip on the hot rolling winding device by detecting the mandrel driving electric current decreased state and/the mandrel velocity increasing state. CONSTITUTION:The caluculator 21 inputs the speed instruction P1, the electric current (tension) instruction P2 to the mandrel driving device 22 through the speed/electric electric current control changeover switching device 24. The mandrel driving device 22 controls the mandrel driving motor 23 based o the speed instruction P1 and the electric current (tension) instruction P2. Further, the slip detector 30 detects the slip between the strip 1 and the mandrel 11 by receiving the computed result of the electric current (tension) decreasing quantity computing part 33 and the speed increasing quantity computing part 34 and the wrapper roll opening signal from the caluculating machine 21 based on the driving electric current (tension) decreasing quantity of the mandrel 11 and/or the speed increasing quantity of the mandrel 11. And the slip judging part 35 outputs the slip detection information P4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for detecting slip between a strip and a mandrel in a hot rolling winding device.

[Prior Art] Conventionally, as described in Japanese Unexamined Patent Publication No. 183130/1983,
When winding a strip onto a mandrel that comes out of the finishing stand of a hot rolling mill, the rate of rotational change of the mandrel when the tip of the strip is held by a wrapper roll and wound around the mandrel is detected, and this rate of rotational change is determined by a predetermined value. A method is disclosed for detecting completion of winding by reaching a level.

In a conventional hot rolling winding device, after the completion of winding of the strip is detected by the method described above, the wrapper roll is opened and the speed of the mandrel is increased. There is no surefire way to detect it.

Therefore, this slip is detected by having the operator visually monitor the mandrel driving ammeter and determining the extent of the current drop.

[Problems to be Solved and Attempted by the Invention] However, the conventional method of visually determining the degree of current drop by an operator has the following problems.

■Since the amount of decrease in current and the time to return to normal current vary depending on the degree of slip, it is extremely difficult to reliably detect whether or not a certain degree of slip has occurred, regardless of individual differences.

■This problem may occur when the operator is concentrating on other tasks and is unable to monitor the ammeter.

(2) Since the occurrence of slip has a large effect on the quality of the strip, the above (2) and (3) are major problems in terms of quality control.

SUMMARY OF THE INVENTION An object of the present invention is to reliably detect slippage between a strip and a mandrel in a hot rolling winding device and to improve strip quality control.

[Means for Solving the Problems] The present invention as set forth in claim 1 provides a hot rolled winding device comprising a mandrel for winding a hot strip, and a wrapper roll for winding a tip of the strip around the mandrel. In a method for detecting slip between a strip and a mandrel in a winding device, slip between a strip and a mandrel is detected based on a state in which the driving current of the mandrel decreases and/or a state in which the speed of the mandrel increases after the wrapper roll is opened. .

The present invention as set forth in claim 2 provides a slip between the strip and the mandrel in a hot rolling winding device comprising a mandrel for winding the hot strip and a wrapper roll for winding the tip of the strip around the mandrel. The detection device includes a current detector that detects the driving current of the mandrel, a speed detector that detects the speed of the mandrel, and a current reduction amount calculation unit that calculates the amount of reduction in the driving current of the mandrel based on the detection result of the current detector. Then, after obtaining the detection results of the speed detector and calculating the speed increase amount of the mandrel, the calculation results of the current decrease amount calculation section and the speed increase amount calculation section are obtained, and after the bugle roll is opened, The device is configured to include a slip determination unit that detects slip between the strip and the mandrel based on a state in which the driving current of the mandrel is decreased and/or a state in which the speed of the mandrel is increased.

[Function] In a hot rolling winding device, when the mandrel is in a tension control state, the force that balances the tension bone torque generated by the mandrel is the seaming force from the strip multiplied by the coefficient of static friction between the strip and the mandrel. This is the value. However, if the seaming force is insufficient, there will be insufficient force to balance the tension bone torque generated by the mandrel, and the strip and mandrel will enter into a state of dynamic friction.

The phenomenon of shifting to this dynamic friction state is slip.

If slipping occurs, the mandrel speed increases relative to the stripping speed due to the transition from static friction to dynamic friction, and the mandrel tension, that is, the driving current decreases.

Therefore, according to the present invention, the occurrence of slip can be accurately detected by detecting the state in which the driving current of the mandrel decreases and the state in which the mandrel speed increases. Therefore, it is possible to reliably detect slippage between the strip and the mandrel in the hot rolling winding device, and improve strip quality control.

[Example] Fig. 1 is a block diagram showing a slip detection device according to an embodiment of the present invention, Fig. 2 is a flow chart showing a slip detection method of the invention, and Fig. 3 shows slip detection results according to the invention. It is a line diagram.

The hot winding device 10 is installed at the end of the runout table on the exit side of the finishing stand of the hot rolling mill, and includes a site guide,
It consists of pinch rolls, mandrels, bugle rolls, and tilling rolls. In addition, in Figure 1,
1 is a coil (strip), and 11 is a mandrel.

This hot winding device 10 operates as shown in (1) to (2) below.

■Until the tip of the strip reaches the hot winding device 10, there is a runout table, pinch roll, bugle roll, etc.
The mandrel is set at a speed greater than the speed of the strip tip. Thereby, the leading end of the strip is smoothly guided to the winding device 10.

■The tip of the strip passes through the pinch roll and enters between the mandrel and the bugle roll. The strip is then wound around the mandrel by the rotation of the wrapper roll, and is wound around the mandrel under the effect of the pressing force of the wrapper roll. The bugle roll then opens outward.

■After winding the tip of the strip, the mandrel motor winds the coil while applying tension to the strip under current control. When the trailing end of the strip passes through the finishing stand, the winding tension is maintained by the back electromotive force of the pinch roll motor. The runout table is also set at a speed lower than the pinch roll speed to prevent the strip from being fed in, and tension is applied to the runout table.

When the tail is just before the down coiler, raise the tilling roll and complete the winding of the coil while holding the tail.

At this time, the winding device 10 controls the mandrel 11 by the control system shown in FIG. In FIG. 1, 21 is a winding device control computer, 22 is a mandrel drive device, and 23 is a mandrel drive motor.

The computer 21 outputs the speed command PI and the current (tension) command P2 to the mandrel drive device 22 via the speed/current control switching device 24, and the mandrel drive device 22 outputs the speed command P
1. Control the mandrel drive motor 23 based on the current (tension) command P2.

However, the winding device 10 includes a slip detection device 30.

The slip detection device 30 includes a current detector 31 that detects the drive current of the mandrel 11 and a speed detector 32 that detects the speed of the mandrel 11.

Further, the slip detection device 30 obtains the detection result of the current detector 31 and the above-mentioned current (tension) command P2, and operates the mandrel 11.
a current (tension) decrease amount calculation section 33 that calculates the amount of drive current (tension) decrease in the mandrel 11; and a speed increase amount that calculates the amount of speed increase of the mandrel 11 by obtaining the detection result of the speed detector 32 and the above-mentioned speed command P1. It has an arithmetic unit 34.

Furthermore, the slip detection device 30 obtains the calculation results of the current (tension) decrease amount calculation section 33 and the speed increase amount calculation section 34 and the bugle roll release signal P3 from the computer 21, and detects the mandrel 11 after the bugle roll is released. A slip between the strip 1 and the mandrel 11 is detected based on the amount of decrease in the drive current (tension) and/or the amount of increase in the speed of the mandrel 11. Then, the slip determination section 35 outputs slip detection information P4.

FIG. 2 is a diagram showing a specific control procedure of the slip detection device 3o. After obtaining the bugle roll release signal P3, the slip detection device 30 issues a current (tension) command P2. and the respective deviation amounts with respect to the speed command P1, and the slip determination unit 35 calculates the deviation amounts based on predetermined threshold values X(χ) and Y(%
). Then, the slip determination unit 35 considers the slip behavior as described above, and determines that a slip occurs when both threshold values are exceeded.

FIG. 3 shows the results of slip detection using the control procedure shown in FIG. 2. (2) is the mandrel current, (2) is the mandrel speed, and S is the slip detection information.

In the above example, the presence or absence of slip was determined based on both the amount of current decrease and the amount of speed increase. However, from the slip behavior as described above, it is possible to determine with high reliability whether or not there is a slip even if the motor only falters in either the current decreasing state or the speed increasing state.

Further, in the above embodiment, the presence or absence of slip was determined using the amount of deviation with respect to each command value of current and speed. However, in implementing the present invention, considering that the behavior of speed increase and current decrease when slip occurs is much faster than that during normal winding, it is necessary to It goes without saying that even if the presence or absence of slip is determined using the rate of change of , it is possible to accurately detect slip.

As described above, according to the present invention, slippage between the strip and the mandrel can be accurately detected, which is extremely useful for strip quality control. In particular, by providing the slip detection information P4 of the slip determination section 35 to the quality control computer, reliable quality control of the strip can be realized.

Further, by using the slip detection device 30 of the present invention in combination with an early recovery device after slip occurrence, such as a mandrel expansion device, it is possible to reduce the amount of slip occurrence.

[Effects of the Invention] According to the present invention, it is possible to reliably detect slippage between the strip and the mandrel in the hot rolling winding device, and improve the quality control of the strip.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a slip detection device according to an embodiment of the present invention, FIG. 2 is a flowchart showing a slip detection method of the present invention, and FIG. 3 is a diagram showing slip detection results according to the present invention. . DESCRIPTION OF SYMBOLS 1... Coil (strip), 10... Hot winding device, 11... Mandrel, 30... Slip detection device, 1... Current detector, 2... Speed detector, 3 ...Current (tension) decrease amount calculation section, 4. Speed increase amount calculation section, 5. Slip determination section.

Claims (2)

[Claims] (1) In a method for detecting slip between a strip and a mandrel in a hot rolling winding device that includes a mandrel for winding a hot strip and a wrapper roll for winding a tip of the strip around the mandrel, the wrapper roll is opened. A method for detecting a slip between a strip and a mandrel in a hot rolling winding device, the method comprising detecting a slip between the strip and the mandrel based on a subsequent state in which the drive current of the mandrel decreases and/or a state in which the speed of the mandrel increases. (2) In a slip detection device between a strip and a mandrel in a hot rolling winding device that includes a mandrel for winding a hot strip and a wrapper roll for winding a tip of the strip around the mandrel, driving of the mandrel A current detector that detects the current, a speed detector that detects the speed of the mandrel, a current decrease amount calculation unit that calculates the amount of decrease in the drive current of the mandrel based on the detection result of the current detector, and detection of the speed detector. The speed increase amount calculating section calculates the speed increase amount of the mandrel based on the results, the current decrease amount calculating section and the speed increase amount calculating section obtain the calculation results and calculate the drive current reduction state of the mandrel after the bugle roll is opened. 1. A slip detection device between a strip and a mandrel in a hot rolling winding device, comprising: a slip determination unit that detects slip between the strip and the mandrel based on a speed increase state of the mandrel.