JP3430664B2 - Automatic deceleration method for steel strip coil and control device therefor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic deceleration method for a steel strip coil and a control system therefor.

[0002]

2. Description of the Related Art Conventionally, when a steel strip rolled into a coil is rewound on a payoff reel, if the tail end of the coil is pulled out from the payoff reel at a high speed, the steel strip will be removed. Shows a whiplash-like behavior, which may cause surface flaws and damage surrounding equipment.Therefore, measures such as slowing down the rewinding speed are taken near the end of the coil. .

For example, when automatic deceleration is performed in a continuous processing line such as continuous annealing equipment, the coil outer diameter D ₁ , the coil inner diameter D ₀ , and the plate thickness T are input to the line speed control device as initial values, and the line is operated. measures the information at a line speed v at the time, and calculates the coil remaining length L _C from these data, when this coil remaining length L _C has reached the preset value L _CS, determined further in advance In general, the deceleration rate K _DC (constant) is used to calculate a remaining length point at which the line can be stopped to decelerate.

[0004]

However, in the conventional method as described above, since the plate thickness T is calculated as a fixed value, the part where the plate thickness of the steel strip is not constant (hereinafter referred to as the off-gauge part). Then, the calculation of the coil remaining length L _C causes an error. If it is thicker than the target plate thickness, the strip length will be shortened by that amount, so the tail end will slip out without deceleration in time, and conversely if it is thin, there will be a sufficient remaining length. Since the deceleration is completed, there is no choice but to visually stop the operation, which has a drawback of deteriorating the operation efficiency.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and provides a method and a control device for the method that enables accurate automatic deceleration even with a steel strip coil having an off-gauge portion. To aim.

[0006]

In order to solve the above problems, the present invention considers that the line deceleration rate before starting deceleration, the strip thickness of the steel strip, and the coil diameter are variables, with the deceleration rate of the line being variable. The deceleration rate until the deceleration is completed is calculated from the remaining coil length at the line speed before the deceleration is started, and the deceleration rate is used for deceleration.

That is, the present invention is an automatic deceleration method for a steel strip coil that is rewound by a payoff reel in a continuous processing line, which comprises a step of presetting the coil residual length of the steel strip coil and the setting of this coil residual length. When a deceleration start time is reached, a step of outputting a calculation command at the start of deceleration and a coil outer diameter is calculated from the number of rotations of the payoff reel and a line speed to calculate a change in the coil diameter per one rotation of the payoff reel. a step of determining the thickness Te, then the Rye
And a coil speed, a coil outer diameter, and a plate thickness as variables, and a step of controlling the line speed to be decelerated based on the deceleration rate.

Further, the present invention is an automatic deceleration control device for a steel strip coil rewound by a payoff reel in a continuous processing line, wherein a rotation speed detector for detecting the rotation speed of the payoff reel and the surface of the coil. The distance meter for measuring the distance, the speed detector for detecting the line speed, the rotation speed detector and the distance meter, and the payoff reel rotation speed, the coil outer diameter value, and the line speed are input from the speed detector, respectively. When the remaining coil length reaches a preset value, a deceleration start time calculation command is output, the coil outer diameter at that time is calculated, and the change in the coil diameter per revolution of the payoff reel is calculated. Calculate the plate thickness and use the above line speed, coil outer diameter, and plate thickness as variables.
Obtains a deceleration rate that is an automatic reduction gear of the steel strip coil, wherein the operation control device for deceleration control of the line speed, that consists on the basis of the deceleration rate.

[0009]

[Operation] According to the present invention, the plate thickness of the steel strip is calculated and taken into consideration as a variable for the remaining length calculation, and then the deceleration rate is calculated from the remaining length calculation result and the line speed for deceleration. Even with a steel strip having an off-gauge portion, deceleration can be completed within the predetermined remaining coil length.

The procedure will be specifically described below. Now, assuming that the line speed is v _A , the distance L _S from the speed v _A to the stop can be calculated by the following equation (1).
On the other hand, the coil length, the coil outer diameter D ₁ , the coil inner diameter D ₀ , and the plate thickness T, the distance L _S is expressed by equation (2). Furthermore, (1),
From equation (2), the deceleration rate dv / dt can be calculated by equation (3). The plate thickness T is calculated by the equation (4).

[0011]

[Equation 1]

Where D _{X is the} outer diameter of the coil during rewinding,
D _n -D _n + _1; a change of the coil diameter per payoff reel 1 rotates. In addition, the coil inner diameter D _{0 in the} equation (3) is
Is given as an initial value. From the above, the deceleration rate dv / dt is determined using the line speed v _A , the coil outer diameter D _X during rewinding, and the plate thickness T as variables, and deceleration at this deceleration rate enables automatic deceleration within the remaining length. Becomes

[0013]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a conceptual diagram showing an embodiment of the present invention. In FIG. 1, 1 is a coil, 2 is a payoff reel for rewinding the coil 1, 3 is a deflector roll,
4 is a pinch roll, and 5 is a continuous processing device. 6 is a rotation speed detector for detecting the rotation speed of the pay-off reel 2, 7 is a laser range finder for measuring the distance from a predetermined position to the surface of the coil 1, and 8 is the rotation speed of the deflector roll 3. Is a speed detector for detecting the speed of the steel strip P, and 9 is an arithmetic and control unit.

A coil inner diameter D ₀ is preset in the arithmetic and control unit 9 as an initial setting value, and the number of revolutions N of the pay-off reel 2 which changes momentarily from the number of revolutions detector 6, the distance meter 7 and the velocity detector 8. _R , the outer diameter value D _X of the coil 1, and the transport speed of the steel strip P, that is, the line speed v _A are input. Then, when the remaining coil length L _C calculated by the conventional method reaches a preset value L _CS , a calculation command at the deceleration start time is output, and the following calculation and control are performed based on this calculation command. It The coil outer diameter D ₁ is calculated by the following equation (5) using the rotation speed N _R of the payoff reel 2 and the line speed v _A.

[0015]     D₁= V_A/ ΠN_R                                ………………(Five) One payoff reel hit based on the signal from the distance meter 7
Change in coil diameter (D _n-D_{n + 1}) And calculate
The plate thickness T is calculated using the equation (4). Next, this plate thickness T and line speed v_AAnd rangefinder 7
Coil outer diameter D during rewinding_XAnd coil inner diameter D₀For and
Then, the deceleration rate dv / dt is calculated using the above equation (3). Based on this deceleration rate dv / dt, the payoff reel 2
And the line speed of the pinch roll 4 and continuous processing device 5 are reduced.
Speed control.

FIG. 2 is a characteristic diagram showing the relationship between the line speed and the coil residual length due to the change in plate thickness. The plate thickness T is shown in Fig. 2 (a).
In the case where the rear end is gradually increased as shown in Fig. 2, in the conventional example in which the deceleration rate is constant, as shown by the dotted line in FIG. In the case of the method of the present invention, the line can be stopped at the time when the remaining coil length is 0 as shown by the solid line.

As described above, according to the method of the present invention, the deceleration rate is calculated based on the remaining coil length in consideration of the off-gauge portion to reduce the line speed. Instead, it is possible to stop the line at a predetermined position.

[0018]

As described above, according to the present invention,
Since the plate thickness of the steel strip is calculated and the remaining coil length is calculated, and the deceleration rate is calculated from the remaining coil length and the line speed at the start of deceleration, the coil is decelerated. Enables automatic deceleration of payoff reels,
It is possible to prevent slipping out of the hips.

Further, since the tail end of the coil can be accurately stopped, the deceleration start point can be delayed as compared with the conventional method, so that the margin coil length after deceleration can be reduced. This also has the effect of improving the operating efficiency of the line.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing an embodiment of the present invention.

FIG. 2 is a characteristic diagram showing a relationship between a line speed and a coil remaining length due to a change in plate thickness.

[Explanation of symbols]

1 coil 2 Payoff reel 3 deflector roll 4 pinch rolls 5 Continuous processing equipment 6 rpm detector 7 rangefinder 8 Speed detector 9 arithmetic and control unit P steel strip

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B21C 45/00-49/00

Claims (2)

(57) [Claims] 1. A method for automatically decelerating a steel strip coil rewound by a pay-off reel in a continuous processing line, comprising a step of presetting a coil residual length of the steel strip coil and a set value of the coil residual length being reached. At the time of deceleration, outputting a calculation command at the time of starting deceleration, and calculating a coil outer diameter from the number of rotations of the payoff reel and a line speed, and calculating a change of the coil diameter per one rotation of the payoff reel to determine a plate thickness. Then, the line speed, coil outer diameter, and plate thickness are used as variables.
And a deceleration control of the line speed based on the deceleration rate. 2. An automatic deceleration control device for a steel strip coil rewound by a payoff reel in a continuous processing line, wherein a rotation speed detector for detecting the rotation speed of the payoff reel and a distance to the surface of the coil are measured. Distance meter, a speed detector for detecting the line speed, the rotation speed detector and the distance meter, the pay-off reel rotation speed, the coil outer diameter value, and the line speed are respectively input from the speed detector, and the remaining coil length is input. When the value reaches a preset value, a calculation command at the start of deceleration is output, the coil outer diameter at that time is then calculated, and the change in the coil diameter per one rotation of the payoff reel is calculated to calculate the plate. seeking a thickness, said La
An automatic speed reducer for a steel strip coil, comprising: an arithmetic control unit that obtains a deceleration rate that uses in-speed, coil outer diameter, and plate thickness as variables, and decelerates and controls the line speed based on the deceleration rate.