JPS5966915A - Method for compensating speed of table - Google Patents

Abstract

PURPOSE:To prevent a material to be rolled from the generation of flaw and an electric power converter from tripping, by detecting the sheet thicknesses at the inlet and outlet sides of the material, and changing the carrying speed of a table of the material basing on a specific relative equation, at the time of changing the sheet thickness of the material during running. CONSTITUTION:When the sheet thickness of a material to be rolled is changed steeply while the material is rolled by a mill, the sheet thickness h1 at the inlet side of the material of the mill and the sheet thickness hO at the outlet side are detected. Next, the carrying speed VTi of a table of the material is obtained from said thicknesses h1, hO and the roll speed VR of the mill basing on the equation. Thus, a slip, etc. of the material on the table is prevented by conforming the carrying speed of the table to the speed of the material.

Description

Detailed Description of the Invention (a) Description of the Technical Field The present invention relates to a table for conveying material in a rolling mill that changes the thickness of a material to be rolled (or referred to as a material to be rolled) during rolling. This invention relates to a table speed compensation method.

Note that changing the plate thickness to a large lJ during rolling is referred to as changing plate thickness during rolling.

(b) Explanation of the prior art Changing the plate thickness during running creates different plate thicknesses from one material,
This is done to improve material yield and save energy.

The rolled material has a shape as shown in FIG.

FIG. 1(a) shows the shape before being rolled in a rolling mill.

Figure 1 (b) shows that when the roll interval of the rolling mill is changed during rolling and the material plate thickness is made smaller than before the change, Figure 1 (C
) indicates the shape of the material when it is larger than before the change.

In this way, when the material plate thickness at the exit side of the rolling mill is changed, the material speed at the input side and the material speed at the exit side of the rolling mill change.

Particularly when changing plate thickness during running, the material speed changes at the entrance of the rolling mill become more severe.

In addition, the speed of the table that transports the material to the rolling mill is such that the rolls on the table scrape the material, causing scratches on the material and making it impossible to use it as a product, or the gravity transducer that drives the table running into an overcurrent as it tries to maintain the speed. The speed must be matched to the speed of the milling material being rolled so as not to cause the gravity transducer to trip.

Therefore, if the table speed is conventionally given at a fixed draft value set from the input side material thickness and the exit side thickness predicted by the rolling mill speed, the exit side material plate will be When changing the running plate thickness to change the thickness, a situation occurs where the speed of the material to be rolled and the table speed do not match, causing the above-mentioned problem and hindering the operation.

(C) Purpose of the Invention The present invention has been made based on the above-mentioned circumstances, and it is possible to ensure smooth operation by ensuring that the table speed always matches the speed of the material being rolled in a rolling mill that changes plate thickness during running. The purpose is to provide a table speed compensation method.

(d) Summary of the invention In order to achieve the above object, the present invention has the following configuration. That is, when rolling a material to be rolled in a rolling mill and changing the thickness of the material during rolling, measure the thickness ho of the rolled material on the incoming side and the thickness ho on the exit side of the rolling mill. Based on the plate thickness and the roll speed VFI of the rolling mill, the table conveyance speed V71 of the material to be rolled of the rolling mill is determined, and the table conveyance speed VTI of the table and the speed of the material to be rolled are made to match, and the Eliminates slippage of rolled material.

(e) Structure and operation of the invention The present invention will be explained below with reference to an embodiment shown in FIG.

The material 2 rolled by the first rolling mill 1 is conveyed by the table 3 and rolled by the second rolling mill 4. The present invention is a continuous rolling mill in which material 2 is rolled simultaneously (2 is not applicable).

The second rolling mill 4 uses a rolling device (not shown) to change the distance between rolls to change the thickness of the rolling plate.

The first rolling B&[ has a load cell 5 that can detect the rolling load.
is provided, and the rolling load is inputted from the load cell 5 to the rolling mill exit side material plate thickness detector 6, and the first rolling mill l is input by the following formula.
The exit side material plate thickness 111 is measured.

however, PI: Rolling load of the first ratio rolling mill Ml; Mill constant of Si: Roll interval of It is.

The material 2 leaving the first rolling mill 1 is conveyed as it is by the table 3 in the shape shown in FIG. 1(a).

Therefore, the thickness of the material plate on the outlet side of the first rolling mill 1 measured by equation (1) becomes the thickness of the material plate on the input side of the second rolling mill 4.

The material rolled in the second rolling mill 4 is shown in FIG. 1(b) or (
It becomes the shape of C). The outlet plate thickness hO of the second rolling mill 4 is the second rolling mill 4.
The rolling load is detected by the rotor self provided in the rolling mill 4 (-) and inputted to the material plate thickness detector 8 on the exit side of the rolling mill, and the following formula (
Measured twice.

however Ro: Rolling load of the second rolling mill Mo: Mill constant of So: Roll interval of It is.

Output side material plate thickness detectors 6 and 8 (input side interest plate thickness ht of the second rolling mill 4 measured by 2): Output side material plate thickness 110 is inputted to the input side table speed reference calculator 9 .

In addition to the material plate thicknesses h+ and ho, the roll speed vB of the M2 rolling mill 4 is also input to the entry side table speed reference calculator 9.

The roll speed vB is determined by the motor 10 that drives the second rolling mill 4.
The rotational speed of the second rolling mill m4 is detected by the tachometer starting device 11 directly connected to the shaft of the rolling mill 4, and is determined by multiplying this by the roll diameter and gear ratio of the second rolling mill 4 using the speed detector 14.

At the beginning of the entry table speed standard, the device 9 is expressed by the following equations (3) and (4).
The entrance table speed standard VT is determined by equation (5) derived from equation (5).
Find 1.

Based on my experience, I learned that l b□-hs f中4'``'-语-''--(41 If ho and b+ have a special relationship, it will be a roar.

however, r: rolling reduction rate f: Advanced rate It is.

Note that although the calculation formula used in the entry side table speed reference calculator 9 is an approximate formula, another rolling theoretical formula may be used.

In the present invention, the thickness of the material at the entrance of the second rolling mill is measured at the first rolling mill, but it may also be measured using a thickness meter or the like at the entrance of the second rolling mill.

Moreover, although the second rolling mill roll speed is given using a tachometer generator, there is no problem in giving the speed setting value of the second rolling mill.

The entry table speed reference V71 determined by the entry table speed reference calculator 9 is applied to the power converter 12 that drives the table motor 13 via the lead compensation circuit 10.

The lead compensation circuit 10 compensates for the table's response delay with respect to the speed reference VTI, and may not be provided if the response delay is not a problem.

(f) Effects of the Invention As described above, according to the present invention, the table speed can be changed at any time in accordance with the change in the thickness of the material due to the change in the thickness of the material during running. Smooth operation can be performed without tripping the power converter that drives the table motor.

[Brief explanation of drawings]

FIG. 2 is a diagram showing the shape of the material, and FIG. 2 is a block diagram for embodying the table speed compensation method of the present invention. 1... First rolling mill 2... Material 3... Table 4... Second rolling mill 5... Load cell 6... Rolling machine exit side material plate thickness detector 7... Load cell 8 ...Rolling machine exit side material plate thickness detector 9...Input (111, 1 table speed reference calculator to...
...Motor 11 of the second rolling mill...Tachometer generator [2...Power converter 13...Table motor 14...Speed detector of the second rolling mill

Claims (1)

[Scope of Claims] When rolling a material to be rolled in a rolling mill and changing the thickness of the material to be rolled during rolling, the thickness hI of the material to be rolled at the exit side of the rolling mill and the thickness of the material to be rolled by the exit side of the rolling mill. 1+0, and from these two plate thicknesses and the roll speed Vl of the rolling mill, the table conveyance speed V? of the rolled material of the rolling mill is determined. A table speed compensation method characterized in that I is determined based on .