JP2971390B2 - Shape correction method of metal strip in continuous straightening line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for correcting the shape of a metal strip in a continuous straightening line provided with a skin pass mill or a leveler.

[0002]

2. Description of the Related Art FIG. 2 shows an outline of a conventional straightening line provided with a conventional tension leveler. A metal strip S such as a stainless steel strip unwound from a payoff reel 1 has a welder 3 and a side trimmer. 4. After being sent out through the looper 5 and leveled by a tension leveler (hereinafter simply referred to as leveler) 7 with a predetermined tension applied between the entrance bridle roll 6 and the exit bridle roll 8, the shape is changed. The winding process is performed on the tension reel 2 via the confirmation platen 9 and the shear 10.

By the way, when the line is started / stopped while the metal strip S is being leveled by the leveler 7,
The work roll of the leveler 7 causes a defect called a leveler mark or a roll mark. Therefore, in order to prevent the occurrence of such a leveler mark, when starting or stopping the line, the line speed is temporarily reduced to a low speed, and after the pressure is reduced or released at a speed at which the leveler mark does not occur, the line is accelerated or stopped. In general, measures are taken.

[0004] However, when the leveler 7 is opened at a low speed and under a reduced pressure, the metal strip S passing through the leveler 7 is not leveled during that time, so that a portion whose shape is not corrected occurs. In order to prevent the occurrence of this no leveling part,
An example has been reported in which a method of starting the line after returning the metal strip S in the reverse direction by a length that is not leveled while the leveler is open after the line is stopped has been reported (for example, "Nisshin Steel Engineering Report, No. 54 No. (issued in July 1986,
P.61-68) ”).

In this case, as shown in the drawing, if the side trimmer 4 or the like is provided on the upstream side of the leveler 7, the metal strip S cannot be reversely fed. In this case, the side trimmer 4 and the entrance bridle are not provided. The looper 5 provided between the metal strip S and the roll 6 absorbs the metal strip S that has been fed back. As a result, even when trimming is being performed by the side trimmer 4, the reverse feed can be performed without any trouble.

[0006]

However, in the above-mentioned conventional method, when the metal strip is fed backward and the line is operated to discharge the metal strip stored in the looper, that is, when the looper roll is moved up and down, or When the looper roll comes into contact with or separates from the metal strip, there is a problem that fluctuations in the pass line and tension occur, which adversely affects the shape correction of the metal strip.

An object of the present invention is to provide a method for correcting the shape of a metal strip which has solved the above-mentioned problems of the prior art.

[0008]

In order to solve the above-mentioned problems, the present invention is to provide a skin pass mill or a leveler between the entrance and exit bridle rolls, and to reversely feed the metal strip upstream of the entrance bridle roll. A method for correcting the shape of a metal strip in a continuous straightening line equipped with a device that cannot perform, comprising a looper between the entrance bridle roll and the skin pass mill or leveler,
When the line is stopped, the work roll of the skin pass mill or leveler is opened, the metal strip is sent back and stored in the looper to temporarily stop the line, and when the line is restarted, the work roll of the skin pass mill or the leveler is gradually reduced. A method for correcting the shape of a metal strip in a continuous straightening line, wherein the metal strip is sent out in a reduced state.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic diagram showing a main part of a continuous straightening line according to the present invention,
A vertical looper between the entrance bridle roll 6 and leveler 7
13 is different from the conventional example. The operation of the line configured as described above will be described as follows.

First, when it is necessary to stop the line by welding, coil division, or the like, the work roll of the leveler 7 is gradually opened to allow the metal strip S to pass therethrough to create an unpressed lower portion so as not to generate a leveler mark. And stop. Next, with the leveler 7 with the work roll released, the unpressurized lower part of the metal strip S is fed back to the upstream side to
13 to return to the upstream side of the leveler 7. At this time, since the unpressurized lower portion is entirely absorbed by the vertical looper 13, the side trimmer 4 on the upstream side of the vertical looper 13 does not affect the backward feeding. Further, the tension applied to the metal strip S is also cut off by the entry bridle roll 6 and does not affect the side trimmer 4.

[0011] Even after the unpressurized lower portion that has been fed back in this way is fed into the vertical looper 13, the tension can be maintained by the looper roll 13a. The stored metal strip S is released, the leveler pressure is gradually reduced from the unpressurized lower part, and after the discharge is completed, the operation shifts to the steady operation. In the above example, the leveler is used to correct the shape of the metal strip S. However, the present invention is not limited to this, and the same effect can be obtained even when the shape is corrected using a skin pass mill. Needless to say.

[0012]

As described above, according to the present invention,
In a continuous straightening line with a skin pass mill or leveler between the entrance and exit bridle rolls, a reverse loop is installed upstream of the entrance bridle roll by installing a vertical looper between the entrance side bridle roll and the skin pass mill or leveler. Even if there is equipment that cannot be returned, the vertical looper can absorb the reverse feed portion of the metal strip, so that the equipment that cannot return is not adversely affected.

Also, since the vertical looper is located between the entrance and exit bridle rolls, defects such as meandering caused by fluctuations in tension do not occur in the entrance facility. Furthermore, the unpressed lower part is absorbed by the vertical looper by the reverse feeding, and then the stored metal strip is released while gradually reducing the pressure, whereby a metal strip having a good shape without generation of a leveler mark can be manufactured.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a main part of a continuous straightening line according to the present invention.

FIG. 2 is a schematic view showing an example of a conventional continuous straightening line.

[Explanation of symbols]

 1 Payoff Reel 2 Tension Reel 3 Welder 4 Side Trimmer 5 Looper 5a Looper Roll 5b Deflector Roll 6 Inlet Bridle Roll 7 Leveler (Tension Leveler) 8 Outlet Bridle Roll 9 Shape Check Plate 10 Shear 11 Inlet Deflector Roll 12 Outlet Deflector Roll 13 Vertical looper (looper) 13a Looper roll S Metal strip

Claims (1)

(57) [Claims] 1. A method for correcting the shape of a metal strip in a continuous straightening line comprising a skin pass mill or a leveler between an inlet-side bridle roll and an apparatus which cannot reverse the metal strip upstream of the inlet-side bridle roll. A looper is provided between the entrance side bridle roll and the skin pass mill or leveler. When the line is stopped, the work roll of the skin pass mill or leveler is opened and the metal strip is fed back to store the line in the looper. The method for correcting the shape of a metal strip in a continuous straightening line, wherein the work strip of the skin pass mill or the leveler is gradually lowered and the metal strip is sent out when the line is restarted.