JPH074692B2 - How to trim a strip - Google Patents

Description

The present invention relates to a strip trimming method, and more specifically, to a shear reaction force perpendicular to a strip surface during trimming, and then the shear reaction force. The present invention relates to a method of trimming a strip by obtaining the plate thickness of a strip at a trimming position that is sheared from a force and adjusting the clearance between the upper and lower blades and the overlap amount of overlap depending on the plate thickness.

2. Description of the Related Art In recent years, for the purpose of reducing production cost and improving yield, an automatic controller for strip strip width, that is, AWC has been introduced in the hot rolling process.

By introducing this AWC, the trimming allowance is reduced at the next step, for example, in a slitter, a shear, or an pickling line, at the time of edge trimming.

However, there is a limit to the application of AWC in the unsteady region at the strip front and rear ends. When the trimming margin is reduced by the camber or the like at the front and rear ends, the strip thickness of the hot-rolled sheet or the like sharply becomes thin due to the edge drop.

Therefore, when the trimming reaches the front and rear ends, the clearance or overlap between the upper and lower blades becomes relatively large. Further, if the clearance or overlap becomes excessive in this way, (1), the quality of the trimming surface is deteriorated, and the ear creases and cracks are generated after the cold rolling in the next step.

(2) The trimming waste cannot be separated.

From such a place, conventionally, for strips,
A slitter has been developed in which the upper blade and the lower blade can be moved in the width direction of the strip to change the clearance and the overlap (for example, Japanese Patent Laid-Open No. 58-81515).

However, even with this slitter, it is difficult to actually change the clearance or overlap while actually traveling, and when the trimming margin changes due to the camber of the strip at the front and rear ends of the strip, or when the edge drop occurs. If the plate thickness changes rapidly due to the influence,
No trimming technology has been developed that can change the clearance and overlap in accordance with this.

Therefore, there is a limit in reducing the trimming margin.

Clearance and overlap of the upper and lower blades in the trimmer are based on the standard thickness of the strip center,
It is determined by this and no consideration is given to the edge drop at the front and rear ends of the strip. In particular, when the trimming margin is reduced, the influence of the edge drop at the front and rear ends of the strip is great, and if the clearance and overlap are determined as described above by ignoring this, the above problems occur.

Problems to be Solved by the Invention The present invention aims to solve these problems, and in detail,
An object of the present invention is to provide a trimming method capable of reducing the trimming allowance by adjusting the clearance between the upper blade and the lower blade, the strip width and the thickness at the trimming position, and improving yield and preventing troubles. And

<Structure of the Invention> Means for Solving the Problems and Their Actions That is, the method of the present invention is such that when the edge portion of the strip is continuously trimmed between the upper blade and the lower blade of the trimmer device, the trimming is performed in advance. The relationship between the plate thickness of the strip and the shear reaction force in the direction perpendicular to the strip surface is obtained for each steel type of the strip to be detected, and the shear reaction force perpendicular to the surface of the strip is continuously detected. It is characterized in that the change in plate thickness of the strip at the trimming position is obtained from the above, and one or both of the clearance and the overlap between the upper blade and the lower blade are adjusted according to the change in plate thickness.

The structure and operation of the present invention will be described below with reference to the drawings.

First, FIG. 1 is a perspective view of an example of a trimmer device for carrying out the method of the present invention. A load cell 5 is incorporated in this apparatus, and the shear reaction force in the direction perpendicular to the surface of the strip can be detected by the load cell 5.

Reference numeral 1 is a trimmer upper blade, 2 is a trimmer lower blade, and each blade 1, 2 is held and rotated by a trimmer shaft box 3 and 4 via a spindle (not shown).

The upper blade 1 is vertically moved up and down together with the axle box 3, and the overlap with the lower blade 2 is adjustable. The lower blade 2 moves laterally together with the shaft box 4, and the clearance between the lower blade 2 and the upper blade 1 is adjustable.

That is, the screw shaft 6 screw-engaged with the worm gear 7 is driven via the worm 8 rotatably driven by the motor 9 on the base 23 and the worm gear 7 meshing with the worm 8, and the shaft box 3 is moved up and down to adjust the overlap. To do.

The shear reaction force P in the direction perpendicular to the strip surface is directly received by the load cell 5 interposed between the screw 6 and the axle box 3.

On the other hand, the clearance is adjusted by moving the screw shaft 24 screw-engaged with the worm gear 20 to the left or right or in the lateral direction via the worm 21 rotatably driven by the motor 22 and the worm gear 20 meshing with the worm 21.

The upper blade 1 is fixed without moving in the lateral direction, while the lower blade 2 is fixed without moving in the vertical direction. Further, the trimmer device having this configuration can be moved in the left-right direction, that is, in the lateral direction, and the trimming width can be adjusted according to the width of the strip.

When trimming the strip with the trimmer device having the above-described configuration, the shear reaction force is detected by the load cell 5, while the strip thickness is estimated from the shear reaction force. , Adjust the overlap amount of overlap.

That is, FIG. 2 shows a circuit of an example of a controller for controlling the clearance based on the shear reaction force perpendicular to the strip surface at the time of trimming according to the method of the present invention. In FIG. 2, 10 is a strip and 11 is a controller. The control device 11 is provided with the following arithmetic circuits 12, 13, 14, and 15 for selecting mathematical formulas according to the steel types A, B, C ... Of the strip 10.

When the shear reaction force P perpendicular to the strip surface at the time of trimming is detected as the output value of the load cell 5 in the circuit 12, the strip thickness t selected according to the steel type and the shear reaction force P are detected from the relational expression. Is required. That is,
The shear reaction force of the strip surface when trimming a strip having the reference plate thickness to is referred to as a reference shear reaction force Po, and the difference between this reference shear reaction force Po and the measured shear reaction force Pm is referred to as ΔP. Based on this ΔP, the plate thickness variation amount Δt with respect to the reference plate thickness to is calculated to obtain the strip plate thickness variation.

Next, the circuit 13 calculates the clearance correction amount ΔC corresponding to the plate thickness variation amount Δt.

On the other hand, the reference plate thickness for the steel type selected by the circuit 14
The reference clearance Co corresponding to to is obtained.

In addition to the reference clearance Co and the previously obtained clearance correction amount ΔC, the circuit 15 uses the trimmer device to move the upper and lower blades 1, 2
The actually measured clearance C _FB actually measured in is introduced.

Based on these information Co, ΔC, and C _FB , the clearance adjustment amount Cp is calculated by the equations Cp = Co + ΔC−C _FB (1) and (1).

The clearance is automatically adjusted by the clearance adjusting device including the motor 22, the worm 21, the worm gear 20, and the screw shaft 24 so that the Cp becomes zero.

The steel types A, B, C of the strip to be trimmed
............ is input, the formula corresponding to the steel type is selected in each control circuit 12, 13, 14, 15 and the reference plate thickness to (normally as described above is set in the control circuits 12, 14). Enter the strip thickness at the center of the strip).

In short, in the present invention, when the shear reaction force Pm perpendicular to the strip surface is measured by the load cell 5, the circuit 12 calculates the plate thickness variation amount Δt with respect to the reference plate thickness to, and the circuit 13 corrects the clearance from this Δt. The amount ΔC is obtained.

From the circuit 14, the reference clearance Co corresponding to the reference plate thickness to
Is output, and the circuit is output together with the clearance correction amount ΔC.
Entered in 15.

On the other hand, the actual measurement value C _FB of the clearance between the upper and lower blades 1 and 2 is also fed back to the circuit 15, and the clearance adjustment amount Cp is calculated. The clearance between the upper and lower blades 1 and 2 is adjusted so that this Cp becomes zero.

FIG. 3 shows another embodiment, in which steel types A, B,
C, ......... Each relation between shear reaction force P and plate thickness t, plate thickness t
And the relational expression of the clearance C are incorporated in the respective control circuits 25 and 26.

That is, the shear reaction force acting on the upper and lower blades is applied to the load cell 5
The circuit thickness is directly detected by the circuit 25 from the detected value P.

The clearance C corresponding to the plate thickness t is obtained by the circuit 26. Further, in the circuit 27, the clearance C is compared with the actual clearance value C _FB, and the motor 22, the worm 21, the worm gear 20, and the screw shaft 24 are adjusted so that the difference Cp becomes zero.
The clearance is automatically adjusted by the clearance adjusting device.

In the above, the automatic adjustment of the clearance is described, but regarding the overlap, the shear reaction force is detected by the load cell, the plate thickness is continuously calculated from this detected value, and the overlap corresponding to this plate thickness is detected. The lap amount of can be automatically adjusted in exactly the same way. Since the description is duplicated here, the description is omitted.

Of course, depending on the steel type and plate thickness change conditions, it may be sufficient to adjust only one of the clearance and the overlap, and in some cases it is necessary to adjust both of them at the same time.
Formulas that take this into consideration are prepared in the arithmetic circuit.

Examples Hereinafter, examples will be further described.

First, when the clearance during trimin was controlled by the method of the present invention by the clearance control device shown in FIG. 2, it was as shown in FIGS. 4 (a), (b) and (c).

When trimming the strip, the plate width changed as shown in FIG. 4 (a). In response to the change in the plate width, the fluctuation ΔP of the shear reaction force was detected in the load cell as shown in FIG. 4 (b).

If the adjustment is made by the method of the present invention regardless of the variation of the plate thickness as described above, the clearance is adjusted according to these variations as shown in FIG. The trouble such as did not occur.

When trimming the strip, the strip width changes (ΔB) as shown in FIGS. 4 (a) and 4 (b), and the strip width changes (ΔB) as shown in FIGS. 4 (a) and 4 (b). Based on this, the shear reaction force changes (ΔP). Nevertheless, conventionally, trimming is performed under the condition of constant clearance.

On the other hand, according to the method of the present invention, it is possible to obtain a change in the shear reaction force and a change in the plate thickness according to the change in the plate width, and correct the clearance accordingly.

<Effects of the Invention> As described above, the method of the present invention, the edge portion of the strip that is sheared between the upper blade and the lower blade, that is, the shear reaction in the direction perpendicular to the surface at the edge portion of the trimming position. The change in force is continuously detected, the plate thickness change of the strip at the trimming position is obtained from this, and the clearance and / or overlap between the upper and lower blades are adjusted according to this plate thickness change for trimming. . According to the method of the present invention,
Conventionally, the trimming allowance, which was required to be about 3.5 times the plate thickness (both sides), is about 2 times the plate thickness (both sides), and trimming will be sufficient.

Therefore, the material can be significantly reduced, and line troubles such as ear marks and ear cracks and line stop due to trimming failure can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of an example of a trimmer device for carrying out the method of the present invention, FIG. 2 is a block diagram of an example of a control circuit diagram for controlling clearance by the method of the present invention, and FIG. 3 is a block of another control circuit diagram. FIGS. 4 (a), 4 (b), and 4 (c) are graphs showing examples controlled by the method of the present invention. Reference numeral 1 ... Upper blade 2 ... Lower blade 3 ... Upper blade bearing box 4 ... Lower blade bearing box 5 ... Load cell 6 ... Reduction screw 7, 20 ... Worm gear 8, 21 ... Worm 9 ... Motor 10 …… Strip 11 …… Trimmer control device 12,13,14,15 …… Control circuit 22 …… Motor 23 …… Base 24 …… Screw shaft

Claims (1)

[Claims] 1. When continuously trimming an edge portion of a strip between an upper blade and a lower blade of a trimmer device, a strip thickness and a strip surface are previously set for each steel type of the strip to be trimmed. The relationship with the vertical shear reaction force is obtained, the shear reaction force perpendicular to the surface of the strip is continuously detected, the strip thickness change of the strip at the trimming position is obtained from this detected value, and this strip thickness change A trimming method for a strip, which comprises adjusting one or both of a clearance or an overlap between the upper blade and the lower blade according to the above.