JPH1071410A - Method for adjusting zero point of screw-down location in 2-stage horizontal rolling mill and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for adjusting the zero point of screwdown location suitable to a 2-stage horizontal rolling mill the reduction fastening force of which is small or with which kiss-roll is impossible and device therefor. SOLUTION: Hydraulic jacks 21 are respectively interposed on the operator side and drive side of the gap between upper and lower work rolls 2, 3 in an opened state and respective roll gaps on the operator side and drive side are measured by executing one-point loading of a heavy load in the actual rolling region to the hydraulic jacks 21. The obtained respective roll gaps on the operator side and drive side are compared and, when there is difference between both, the zero point of the screw-down location is adjusted by adjusting roll position so as to eliminate the difference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for adjusting a rolling position zero of a two-stage horizontal rolling mill.

[0002]

2. Description of the Related Art Conventionally, a rolling mill used for producing steel or the like has a structure as shown in FIG. That is,
For example, 2 used for a rough mill of a hot strip mill
1 shows an outline of a step type horizontal rolling mill, in which a pair of upper and lower work rolls 2 and 3 are housed in a housing 1 by being respectively supported by upper and lower roll chocks 4 and 5. The upper work roll 2 can be moved up and down by a pressure block 6, a screw 7, a worm wheel 8, and a pressure reduction device 9 including a pressure reduction motor (not shown). A lifting device 13 including a worm wheel 12, a lifting motor (not shown), and the like makes it possible to vertically move up and down. A rolling load cell 14 such as a load cell is attached to the screw 7 with a screw nut 15.

When setting the roll gap of such a rolling mill, in a rolling mill having a large rolling force, the upper and lower work rolls 2 and 3 are set in a kiss roll state, and the rolling screw 7 is actually rolled while rotating the rolls normally. Machine for example 10
Roll up to 00 ~ 1500ton, then roll gap 0
In general, a so-called interference method for performing zero adjustment (hereinafter abbreviated as zero tone) by inputting mm is used. If there is a difference between the rolling load value on the operator side and the rolling load value on the drive side, the one-side reduction position is adjusted so that the difference, which is the reference value, is within ± 15 ton.

[0004] By the way, there are some rolling mills to which the above-mentioned setting method cannot be applied. That is, for example, as in a two-stage horizontal rolling mill used on the front side of a rough mill,
Since it is necessary to adjust the roll gap at high speed, it is necessary to reduce the reduction ratio of the reduction drive unit so that the reduction force is only about tens of tons, or the upper and lower roll chocks interfere with each other. That cannot be kiss rolled.

In the case of a rolling mill to which such a setting method cannot be applied, as shown in FIG.
For example, two wooden bars (or square blocks made of steel) of about 100 mm square are placed at both ends between the three units, and are squeezed under light pressure to perform mechanical backlash and poor surface contact of machine parts. Then, the so-called timber bar sticking method is used in which the roll gap is measured by a measuring tool such as an inner path and the difference between the right and left roll gaps is adjusted.

[0006]

However, in the case of the above-described conventional method of pinching a timber rod, there are the following drawbacks. Since rolling reduction of only several tens of tons can be performed, the rigidity characteristics of the rolling mill become non-linear in the low load range, and the roll gap in the actual rolling range requiring a high load cannot be set properly. Inability to measure. Since only a load of less than about 1.0 ton is applied since the wood is inserted, it is not possible to suppress mechanical backlash and poor surface contact of mechanical parts.
Roll gap or difference between right and left roll gaps during actual rolling in a high load area such as 2000ton. The measurement of the roll gap must rely on manual labor, and therefore, there is large variation among operators, poor reproducibility, and so-called 3K work. In practical terms, roll replacement and zero adjustment are performed during suspension work, etc.
The roll gap difference may be adjusted again based on the result of checking the bending of the material at the time of subsequent rolling restart, which is extremely inefficient.

An object of the present invention is to provide a method and an apparatus for adjusting a zero position of a rolling position of a two-stage horizontal rolling mill which solves the above-mentioned problems of the prior art.

[0008]

SUMMARY OF THE INVENTION The present invention is a method for adjusting a zero point of a rolling position in a two-stage horizontal rolling mill,
A step of interposing hydraulic jacks on the operator side and the drive side of the gap between the upper and lower work rolls in an open state, and applying a high load in the actual rolling area to the hydraulic jacks at one point, and The process of measuring the roll gap and comparing the obtained operator side and drive side roll gaps,
And a step of adjusting the roll position so as to eliminate the difference if there is a difference between the two.

A step of continuously changing the load of the hydraulic jack from 0 to a predetermined load value in the actual rolling area, detecting a roll gap at that time, and calculating mill constants on the operator side and the drive side. May be added. Further, the present invention is an apparatus for adjusting a zero point of a rolling position in a two-stage horizontal rolling mill, wherein a hydraulic jack is provided one by one near each end between upper and lower work rolls, and the hydraulic jack is incorporated in the hydraulic jack. A displacement sensor for measuring the stroke of the rod, a hydraulic pump for supplying hydraulic pressure to the hydraulic jack, a drive motor for driving the hydraulic pump, a hydraulic sensor for measuring the hydraulic pressure of the hydraulic pump, and the displacement sensor A two-stage horizontal rolling mill comprising: a calculation control device for performing predetermined calculation processing by inputting a detection signal from a hydraulic pressure sensor and performing stepwise control of the hydraulic pressure of the hydraulic pump via a drive motor. This is a zero position adjustment device for the machine.

[0010] The arithmetic and control unit may incorporate a zero-tone mode and a mill constant measurement mode.

[0011]

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 an embodiment of the present invention, and FIG. 2 is a block diagram of a rolling position zero point adjusting device of the present invention. The same members as those in the conventional example are denoted by the same reference numerals, and description thereof will be omitted.

In these figures, reference numeral 21 denotes a hydraulic jack which is interposed between the upper and lower work rolls 2 and 3 in an open state, one near each end of the operator side and the drive side. Reference numeral 22 denotes a displacement sensor such as a magnescale, which is built in the hydraulic jack 21 and is configured to measure the stroke of the rod 21a. 23 is a hydraulic jack
A hydraulic pump for supplying a hydraulic pressure to the oil pump 21 via an oil supply pipe 24, a drive motor 25 for the hydraulic pump 23, and a hydraulic sensor 26 attached to the oil supply pipe 24.

An arithmetic and control unit 27 such as a personal computer inputs detection signals from the two displacement sensors 22 and one oil pressure sensor 26 to perform predetermined arithmetic processing.
, And has a function of controlling the hydraulic pressure of the hydraulic pump 23 in a stepwise manner, and two modes of a zero adjustment mode and a mill constant measurement mode are incorporated. Reference numeral 28 denotes a display device for displaying the result of the arithmetic processing by the arithmetic and control unit 27.

The procedure for performing the zero adjustment of the roll gap by using the rolling position zero point adjusting apparatus of the present invention thus configured will be described below. (i) The upper and lower work rolls 2 and 3 are opened to provide an appropriate gap, and two hydraulic jacks 21 are interposed in the gap near both ends of the operator side and the drive side. (ii) The arithmetic control unit 27 selects the zero-tone mode. (iii) First, the drive motor 25 is started to supply hydraulic pressure from the hydraulic pump 23 to the hydraulic jack 21, and a high load set pressure corresponding to an actual rolling area of 500 to 1000 tons on one side between the upper and lower work rolls 2 and 3. , And the roll gap and the oil pressure value are similarly input to the arithmetic and control unit 27. (iv) Then, the arithmetic and control unit 27 compares the left and right (operator side and drive side) roll gaps. Here, if the set pressure is, for example, 1000ton,
If there is a difference of, for example, ± 0.1 mm or more between the left and right roll gaps, the hydraulic pump 23 is stopped, the pressure of the hydraulic jack 21 is lowered once, and then the pressure reduction device 9 is operated to eliminate the single pressure reduction state. The left and right roll gaps are adjusted to be equal, for example. (v) Start the hydraulic pump 23 again and start the hydraulic jack
Step 21 is repeated until the difference between the left and right roll gaps becomes ± 0.1 mm or less, and the roll gap and the oil pressure value are input to the arithmetic and control unit 27, and the final result is displayed on the display unit 28. To be displayed. (vi) The hydraulic pump 23 is stopped, the pressure of the hydraulic jack 21 is reduced, and the zero adjustment ends.

Next, the procedure of the subsequent measurement of the mill constant will be described. (vii) The arithmetic control unit 27 selects the mill constant measurement mode. (viii) The load of the hydraulic jack 21 is continuously changed from 0 to a predetermined load value in the actual rolling area, for example, 0 ton → 1000 ton → 0 ton, and the roll gap and the oil pressure value at that time are simultaneously detected and closed. The direction and opening direction data are input to the arithmetic and control unit 27, respectively. (ix) The arithmetic and control unit 27 calculates the operator side and drive side mill constants Kh _OP and Kh _DR and displays them on the display unit 28.

That is, when the relationship between the average roll gap displacement and the average load value is plotted on two-dimensional coordinates, for example, a relationship as shown in FIG. 3 is obtained. Non-linear area due to poor surface contact, etc.
The curve is regressed in the linear region of 1000 tons, and the slope Kh of the regression line (solid line) is calculated as a mill constant (ton / mm). By performing this individually for the operator side and the drive side, as shown in FIGS. 4 (a) and 4 (b),
The respective mill constants Kh _OP and Kh _DR can be calculated.

Incidentally, the management reference value ε of the mill constant is usually about 3 to 5%, and is generally calculated by the following equation. ε = (| Kh _OP −Kh _DR | / Kh) × 100 ≦ 3-5% where Kh is the average mill constant of the operator side and the drive side. (x) The hydraulic pump 23 is stopped to reduce the pressure of the hydraulic jack 21, and the mill constant measurement is completed.

In the above example, the load amount of the hydraulic jack has been described as being detected by the hydraulic sensor. However, in the case of a rolling mill having a rolling load meter such as a load cell in the housing, the rolling load meter is used. You may do so. It is needless to say that the accuracy of the rolling load cell can be checked by using the method of measuring the mill constant.

[0019]

As described above, according to the present invention,
While pressurizing between the rolls using a hydraulic jack, by measuring the change in the roll gap at that time, zero adjustment or mill constant measurement was performed, so even if the rolling mill has a low rolling-in force, The zero-tone or mill constant measurement can be performed in a short time at low cost and with high accuracy.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a main part of an embodiment of the present invention.

FIG. 2 is a block diagram of a rolling position zero adjustment device of the present invention.

FIG. 3 is a characteristic diagram illustrating measurement of a mill constant.

FIG. 4 is a characteristic diagram of (a) an operator side and (b) a drive side of the mill constant measurement.

FIG. 5 is a side sectional view showing an example of a conventional rolling mill.

FIG. 6 is an explanatory diagram of a conventional method of pinching a timber bar.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Upper work roll 3 Lower work roll 4 Upper roll chock 5 Lower roll chock 6 Pressure block 7 Pressure screw 8 Warm wheel 9 Pressure reduction device 10 Pressure block 11 Pressure screw 12 Worm wheel 13 Pressure device 14 Rolling load meter 15 Screw nut 16 Wood stick 21 Hydraulic jack 22 Displacement sensor 23 Hydraulic pump 24 Oil supply pipe 25 Drive motor 26 Hydraulic sensor 27 Arithmetic control unit 28 Display unit

Claims (4)

[Claims] 1. A method for adjusting a zero point of a rolling position in a two-stage horizontal rolling mill, comprising: interposing hydraulic jacks on an operator side and a drive side of a gap between upper and lower work rolls in an open state, respectively. A step of applying a high load in the actual rolling zone to the hydraulic jack at one point and measuring the roll gaps on the operator side and the drive side, and comparing the obtained roll gaps on the operator side and the drive side. Adjusting the roll position to eliminate the difference if there is a difference, the method of adjusting the rolling position zero of the two-stage horizontal rolling mill. 2. A step of continuously changing a load of the hydraulic jack from 0 to a predetermined load value in an actual rolling area, detecting a roll gap at that time, and calculating mill constants on an operator side and a drive side. 2. The method for adjusting a rolling position zero of a two-stage horizontal rolling mill according to claim 1, wherein: 3. A device for adjusting a zero point of a rolling position in a two-stage horizontal rolling mill, wherein hydraulic jacks are interposed one by one near both ends between upper and lower work rolls, and are built in the hydraulic jacks. A displacement sensor for measuring the stroke of the lever, a hydraulic pump for supplying hydraulic pressure to the hydraulic jack, a drive motor for driving the hydraulic pump, a hydraulic sensor for measuring the hydraulic pressure of the hydraulic pump, the displacement sensor and A two-stage horizontal rolling mill, comprising: a calculation control device that inputs a detection signal from a hydraulic pressure sensor, performs predetermined calculation processing, and controls stepwise the hydraulic pressure of the hydraulic pump via a drive motor. Zero position adjustment device for rolling. 4. The apparatus for adjusting a rolling position zero of a two-stage horizontal rolling mill according to claim 3, wherein a zero adjustment mode and a mill constant measurement mode are incorporated in the arithmetic and control unit.