JPS6268615A - Rolling method for steel material by shifted mill - Google Patents

Abstract

PURPOSE:To prevent distortion and bending of steel material and to stabilize conveying by controlling a roll gap and a deflection extent of axis to symme trize the section of rolling steel materials with respect to the width center line by detecting the roll profile. CONSTITUTION:A profile measuring machine 42 consisting of profile detectors 44, 46 and a profile arithmetic unit 48 is provided to a shifted mill to detect profiles of work rolls 12, 14. In the stage of rolling the steel materials, the gap between the roll 12 and the roll 14 and the extent of deflection are controlled based to the profiles of rolls 12, 14, so that the section of the steel material in the width direction after rolling is symmetrized in line with respect to the center line of the width of the section. In this way, the distortion and bending of the steel materials are prevented and the conveyance of the steel materials is stably performed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a shift mill that rolls a steel material by shifting a pair of work rolls in the axial direction of the work rolls so as to be point symmetrical about their opposing centers. A method of rolling steel materials according to this method.

[Prior Art] When rolling a steel material, the steel material is passed between a pair of work rolls and rolled into a steel material of a predetermined thickness.

When this type of work roll rolls a steel material, its peripheral surface wears out due to friction with the steel material. The circumferential surface of such a work roll may wear locally depending on the temperature distribution and hardness distribution of the steel material. Particularly, wear progresses locally in a portion of the circumferential surface of the work roll corresponding to the edge of the steel material to be rolled. Therefore, the circumferential surface of the work roll wears unevenly,
If irregularities are formed on the circumferential surface, there are problems such as unevenness being formed on the surface of the steel material during rolling of the steel material, and the thickness of the steel material becoming thicker at the edges, resulting in uneven thickness. .

For this reason, a method is known in which the work roll is shifted in the axial direction every time a predetermined number of steel materials are rolled. In this way, by constantly shifting the work roll, the circumferential surface of the work roll is uniformly worn and localized wear is prevented.

[Problems to be Solved by the Invention] However, even when the work rolls are shifted, the amount of wear between the upper and lower work rolls is different. The profile (shape) of the circumferential surface is different from that of the work roll.

Therefore, the gaps formed by the circumferential surfaces of these work rolls facing each other are not only uneven, but also vary in size depending on the location due to shifting. If the steel material is passed between such work rolls as it is, the profile (cross-sectional shape) of the steel material may be left and right asymmetrical, or the steel material may be bent. If they are formed asymmetrically, the conveyance of the steel material becomes unstable, and there is a problem that the steel material may become twisted or come off the conveyance path during conveyance.

[Means to solve a problem] This proposal was made in view of the circumstances of refusal,
It is an object of the present invention to provide a method for rolling steel materials using a shift mill, which can prevent the steel materials from twisting and bending in the shift mill, and can transport the steel materials in a stable state.

The method for rolling steel materials using the Schiff 1-mill according to the present invention is as follows:
In a rolling method that rolls a steel material by shifting a pair of work rolls in the axial direction of the work rolls in a point-symmetrical manner with respect to their opposing centers, the profile of each work roll is detected and the steel material is rolled. , controlling the size of the gap between the pair of work rolls and the amount of deflection of the work rolls based on the profile so that the cross section in the width direction of the steel material after rolling is symmetrical with respect to the center line of the width; It is characterized by

[Embodiments] Next, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 5 of the accompanying drawings.

As shown in FIG. 1, a rolling mill 10 for rolling the steel billet to a predetermined thickness is provided on a conveyance path (not shown) for steel billets (steel materials) during hot rolling. In this rolling R10, a pair of work rolls 12.14 are arranged facing each other vertically with respect to the conveyance path. A first hydraulic cylinder 16 is connected to the upper work roll 12 to shift the upper work roll 12 in the axial direction.
4 is similarly connected to a second hydraulic cylinder 18. These first and second hydraulic cylinders 16, 18 are driven in conjunction with each other in response to a drive signal from a control device 20, which will be described later, so that the pair of work rolls are point symmetrical about their opposing centers. .

The upper work roll 12 and the lower work roll 14 are provided with backup rolls 22 and 28, respectively, which are transferred to their peripheral surfaces.
is provided, thereby applying a predetermined rolling load via the work rolls during rolling of the steel billet, and setting the size of the gap to be formed between the work rolls. Gap setting devices 24 and 26 are installed at both ends of the first upper backup roll 22 via bearings 25, respectively, for applying a pressure 3τ load and adjusting the gap through which the steel billet is passed. It is provided. Each of the gap setting devices 24 and 26 is equipped with a motor that can significantly change the gap between the work rolls, and a hydraulic cylinder with a short changing stroke but a wide reduction force limit, and the gap can be adjusted by operating the motor and hydraulic cylinder. Adjusting the dimensions.

The work roll 12 is supported by a bearing (chock) 34 and housed in a housing 36, as shown in FIG. Similarly, lower work roll 14 is supported by bearings 38 and housed within housing 36 . Further, the upper work roll 12 and the lower work roll 14 are provided with first and second benders 30, 32, respectively, for adjusting the sag of the axis of the work roll. 30 of these vendors
and 32 are attached to one end and the other end of the upper and lower work rolls 12 and 14, respectively. Each bender 30, 32 is configured to apply a predetermined pressure using a hydraulic cylinder in a direction to separate the end portions of the work rolls facing each other from each other, thereby adjusting the degree of deflection of the work rolls. Each bender 30, 32 is connected to the control device 20 in the same way as the shift cylinders described above.

As shown in FIG. 3, the rolling station 10 is further provided with a profile measuring device 42 for detecting the profile of the work rolls 12.14. This profile measuring device 4
2, a first movable member attached to the circumferential surface of the work roll 14;
A profile detector 44 and a second profile detector 46 movable along the circumferential surface of the work roll 12 are provided. Each first and second detector 44.46 is coupled to a profile calculation device 48, and each work roll 12.
Measure 14 profiles. The computing device 48 is connected to the control device 20, and the profiles of the upper and lower work rolls are sent to the control device 20 as data signals. This control [l
The device 20 uses first and second gap setting devices 24.26 based on the information of the profile of the work roll and the shift position of the work roll by the hydraulic cylinder 16.18.
A gap setting signal is sent to the benders 30 and 32, and a signal is also sent to set the pressure to be applied to the benders 30 and 32.

Next, the operation of this embodiment will be described with reference to FIG. 5, which is a flowchart of the control device 20.

In the first snoteb 50, the work roll is shifted by a predetermined amount 1 to 1 in the axial direction of the work roll. In this case, each time one steel billet is rolled, the control device 20 controls the first and second hydraulic cylinders 16.
．． 18 to automatically shift each work roll by a preset amount and store the shifted position in an appropriate memory.

In a second step 52, a pair of work rolls 22.2
Set the gap between 4. In this case, the control device 20 issues an activation signal to the first and second gap setting devices 24 and 26 to set a gap in the thickness of the steel billet to be rolled.

Next, in a third step 54, the deflection l of the work roll is set and predicted. In this case, the first step 50
It is calculated based on the shift position of the work roll set in step 52 and the gap (rolling load) between the work rolls set in the second step 52.

In a fourth step 56, the circumferential profile of the work roll 12.14 is measured. In this step, the first and second detectors 44, 46 each move along the circumferential surface of the work roll and measure the profile of the circumferential surface. The profile of each work roll is stored in memory at an appropriate location in the controller 20.

Next, in a fifth step 58, the plate profile during rolling of the steel billet is calculated. Since the shift position of the work roll is stored in the control device 20 in the first step, the shift position of the work roll 12.14 and the prediction of the amount of roll deflection from the second step 54 and the fourth step are stored in the control device 20. From the no-load roll profile obtained in step 56, the shape of the gap during rolling, that is, the profile of the steel billet after it is passed through this gap and rolled is predicted.

In a sixth step 60, the gap is adjusted so that the profile in the width direction of the steel billet after rolling becomes symmetrical. In this case, the first and second pressing devices are adjusted so that the dimensions Ah and Bh of the gap between the first measurement position @A and the second measurement position B are equal, as shown in FIG. The first position A and the second position B are each located at a distance of 1/4 of the width W of the steel piece from a center line Y that bisects the cross section of the steel piece in the width direction. At these measurement positions @A and B, the dimensions Ah and Bh change according to the gap between the steel slabs, so by pressurizing one of the gap setting devices as shown by the broken line in Fig. 4, the dimensions Ah and Bh can be changed. can be made approximately equal.

Next, in the seventh step 62, a portion C corresponding to the edge of the steel piece,
Vendor 30. to equalize the gap at point D.
Set 32. In this case, the axial deflection of the work roll is adjusted by adjusting the bender. When adjusting the deflection of the axis of the work roll, when one of the benders, for example, the seventh bender 30, is applied according to the lever principle, the second bender 32 is moved as shown by the broken line in FIG.
serves as a fulcrum, so the amount of change in the position closer to the first bender 30 is larger than the amount of change in the position closer to the second bender. Therefore, by adjusting one bender, the dimension Ch, [)
h can be easily set.

In the eighth step 64, Ah and ah are again compared. After setting the vendor in the seventh step 62, the previously set All and Bll may be slightly shifted.

Therefore, calculate the following equation (1) and check the deviation.

1Ah-Bh 1610μm ・・・・・・・・・
...(1) If this formula (1) is not satisfied, the process returns to the sixth step 60, and if the formula (1) is satisfied, the process proceeds to the next ninth step 66, and the vendor and complete the gap adjuster settings.

This repetitive motion is repeated for each shift of the work rolls, or in this case for each passing of the billet. Therefore, the cross section of the steel billet after rolling can be rolled into a shape that is substantially symmetrical about the center line that bisects the width direction. Since the steel billet after rolling has good symmetry, it is possible to stably pass the steel billet and prevent bending of the steel billet.

This invention is not limited to the embodiments described above, and can be modified in various ways without departing from the gist of the invention.

For example, the measurement position of the gap was measured at 1/4 of the width from the bisector and at the edge of the cross section in the width direction of the steel slab, but the measurement position is not limited to this. Any position may be used as long as it is symmetrical with respect to the bisector, such as the dimension at .

Further, in the above-described embodiment, the tolerance at the gap measurement position was set to 10 μmiJ or less, but the tolerance is not limited to this, and any value may be used as long as it is within the tolerance range.

Further, in the above-described embodiment, the work rolls were set every time one steel plate was rolled, but the work rolls are not limited to this, and may be set every 2 or 5 sheets or any other number of times.

[Effects of the Invention] According to this invention, the gap between the pair of work rolls and the amount of deflection of the axis thereof are set so that the cross section of the steel material to be rolled is symmetrical with respect to the center line of its width. The rolled steel material can be rolled into a symmetrical shape in its cross section.

[Brief explanation of drawings]

FIG. 1 is a front view showing the general configuration of a rolling mill according to the present invention, FIG. 2 is a side view of the rolling mill, FIG. 3 is a schematic diagram of work roll profile measurement, and FIG. FIG. 5 is a flow chart showing a method for controlling a work roll according to the present invention. 10...Rolling mill, 12...Upper work roll, 14...
...lower work roll, 16...first hydraulic cylinder,
18... Second hydraulic cylinder, 20... Control device,
24...First gap setting device, 26...Second gap setting device, 30.32...Bender, 42...Profile measuring device. Applicant's agent Patent attorney Takehiko Suzue Figure 3 Figure 4

Claims (1)

[Claims] In a rolling method that rolls a steel material by shifting a pair of work rolls in the axial direction of the work rolls in a point-symmetrical manner with respect to their opposing centers, the profile of each work roll is detected and the steel material is rolled. , controlling the size of the gap between the pair of work rolls and the amount of deflection of the work rolls based on the profile so that the cross section in the width direction of the steel material after rolling is symmetrical with respect to the center line of the width; A method for rolling steel materials using a shift mill, characterized in that: