JPH0716875B2 - Roll grinding control method and apparatus - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method and apparatus for controlling the grinding of a rolling roll incorporated in a rolling mill or the like for rolling metal strips and the like. INDUSTRIAL APPLICABILITY The present invention can be applied not only to rolling rolls, but also to various process lines, for example, a method for controlling grinding of rolls in a line for pickling, plating, heat treatment of strips and the like, and an apparatus therefor.

<Prior Art> In a rolling mill, for example, a hot strip rolling mill, generally only a portion of a rolling roll that comes into contact with a strip is locally worn, and a step is formed between the portion that does not come into contact with the strip. Also, a large number of cracks, so-called rough skin, occur on the surface of the roll that contacts the hot strip. When the strip is rolled with the step and the rough surface, these are directly transferred to the strip. Therefore, normally, rolling is carried out according to a rolling schedule in which the width dimension of the strip to be rolled is gradually reduced so that the step is not transferred to the strip. If the rough skin exceeds the allowable value, a new rolling roll is replaced. However, such a method has many problems that not only the rolling work efficiency is hindered but also the rolling cannot be performed according to an arbitrary rolling schedule.

Therefore, in order to solve this problem, in recent years, the rolling roll was ground while the rolling roll was still incorporated in the rolling mill to remove the above-mentioned steps and surface roughness, and the roll life until recombining and the rolling according to an arbitrary rolling schedule were realized. Various on-line grinding methods for rolling rolls to be tried have been proposed.

The determination of the grinding amount in these conventionally proposed rolling roll grinding methods is performed by [grinding amount = cut amount × retention time] as disclosed in JP-A-60-124410, for example. There is. Here, the depth of cut represents the amount of grinding per unit time under a predetermined grinding condition, and the residence time represents the contact time of the abrasive with the surface of the rolling roll, that is, the time during which grinding is performed. As described above, in the conventionally proposed method for grinding a rolling roll, the amount of grinding is controlled over time.

<Problems to be Solved by the Invention> The conventional method for determining the grinding amount based on time has the following drawbacks.

That is, the factors that determine the amount of grinding are: 1) specifications of the abrasive (grain size, degree of bonding, etc.) 2) grinding speed (rotational speed of the rolling roll) 3) pressing force of the abrasive on the rolling roll 4) grinding mode ( The shape of the grinding material, driving method, etc.) 5) The material of the rolling roll and the presence or absence of lubricating oil, etc., but among the above, the factors of 1) and 3) to 5) can be determined by initial selection, There is no problem in considering it as a fixed condition factor. However, the grinding speed in the item 2) is the rolling speed, which is a variable condition factor whose value constantly changes, and therefore some measure is required.

That is, when grinding is performed under the condition of constant rolling speed, that is, constant grinding speed, all of the factors 1) to 5) described above are fixed condition factors, and the grinding amount increases in proportion to time. Control can be performed easily.

However, when the rolling roll is ground during strip rolling, the rolling speed V _R is not constant as shown in FIG. 4 as an example of the change of the rolling speed with time t, and in order to improve the productivity, After the start of rolling, it is usual to take a speed pattern in which the speed increases from the strip speed V _R1 to the maximum rolling speed V _RMAX that is suitable for the strip and after rolling for a predetermined time, it decreases to the rolling end speed V _R2. is there.

When the grinding amount is determined based on such a speed pattern, the cutting amount, which is the basic value, that is, the grinding amount per unit time, changes with the time pattern described above. Therefore, in order to obtain the required staying time for obtaining the required grinding amount, an advanced calculation such as performing an integral calculation of the cutting amount using the above speed pattern and performing a convergence calculation with the staying time, Need control. It should be noted that such a problem can be solved by performing grinding while the grinding speed can be kept constant, that is, while the strip is not rolled, but in practice,
In order to improve productivity, it is difficult to obtain the time required for grinding while the strip is not rolled, and it is necessary to perform grinding during rolling.

The present invention has been made in view of the conventional problems as described above, it is not necessary to perform a high degree of calculation and control as in the related art, and grinding can be performed with a desired accuracy even during strip rolling, and a large amount of money is required. An object of the present invention is to provide a rolling roll grinding control method and an apparatus thereof, which does not require equipment costs.

<Means for Solving Problems> In order to solve the above problems, a roll grinding control method according to the present invention is applied to a roll grinding control applied to the processing of a strip running while being continuously accelerated and decelerated by a rolling roll. In the method, the step of measuring the peripheral speed of the rolling roll, so that the grinding amount per one rotation of the rolling roll has a relationship inversely proportional to the peripheral speed of the rolling roll, an abrasive material for the rolling roll according to the measured peripheral speed of the rolling roll. By adjusting the pressing force of, the process of grinding by controlling the grinding amount per unit time of the rolling roll to a constant value, the process of measuring the time from the start of grinding, the measured time and preset The step of comparing the grinding time required for obtaining the predetermined total grinding amount, and terminating the grinding at the time of coincidence are characterized by the following steps.

Further, the roll grinding control device according to the present invention is a roll grinding control device applied to the processing of a strip that travels while continuously accelerating and decelerating by a rolling roll, and a pressing force detection for detecting a pressing force of an abrasive material against a rolling roll. A mechanism and a rotation speed detection mechanism for detecting the rotation speed of the rolling roll,
A speed calculation mechanism that calculates the peripheral speed of the rolling roll from the diameter of the rolling roll and the detected rotational speed of the rolling roll, a necessary time calculation mechanism that calculates the grinding time required to obtain a predetermined total grinding amount, and at the start of grinding From the relationship between the grinding time calculation mechanism that calculates the actual grinding time that has elapsed from the above, the pressing force of the abrasive material, the grinding amount per one rotation of the rolling roll, and the peripheral speed of the rolling roll, Based on the calculated value of the peripheral speed of the rolling roll of the speed calculation mechanism, the pressing force of the abrasive is controlled so that the grinding amount per unit time is a constant value, and the calculated value of the actual grinding time is the required value. And a pressure control mechanism for releasing the pressing of the grinding material when the calculated grinding time coincides.

<Operation> In the present invention configured as described above, the peripheral speed of the roll during grinding, that is, for example, the rolling speed is detected and calculated, and the grinding amount per roll revolution and the roll peripheral speed are calculated based on the calculated value. The pressing force of the abrasive material against the roll is controlled by the pressure control mechanism so as to provide an inversely proportional relationship between the two, and grinding is performed so that the grinding amount of the roll per unit time becomes constant. The pressure control mechanism releases the pressing of the abrasive material when the time from the start of grinding matches the time required to obtain the predetermined grinding amount, and finishes the grinding.

<Examples> Hereinafter, the configuration of the present invention will be described in more detail based on the examples shown in the drawings.

FIG. 1 shows an embodiment in which the present invention is applied to a rolling roll grinding device that uses a cup-shaped grindstone as an abrasive and presses this against the circumferential surface of a rolling roll to perform grinding.

In the figure, the cup-shaped grindstone 1 is pressed against the surface of the rolling roll 2 to perform grinding. Cup type grindstone 1 is bearing 3
The grindstone support box 4 is rotatably mounted on the grindstone support box 4 by means of a hydraulic cylinder 5. The grindstone support box 4 is moved in the direction of arrow A by the hydraulic cylinder 5, and the grindstone 1 is pressed against the rolling roll 2. The hydraulic cylinder 5 operates by supplying and discharging pressure oil from the oil supply pipes 6 and 7, and the pressing force of the grindstone 1 against the rolling roll 2 is detected by the pressure detection mechanism 8 attached to the oil supply pipe 7, and the value thereof is the pressure. It is controlled to an arbitrary value by the control mechanism 9. The grindstone 1 is arranged such that its rotation axis is tilted by an angle α with respect to the axis normal of the rolling roll, and by a moving device (not shown) to the position of the grindstone 1 ′ indicated by the chain line in the axial direction of the rolling roll 2 shown by arrow B,
The amount of movement L _P can be moved.

The rolling roll 2 is mounted on a rolling mill housing (not shown) via a bearing 10 and is rotationally driven by a rotary drive device 11 so that the rotational speed N _R of the rolling roll 2 is a rotational speed detecting mechanism 12
And the peripheral speed V _R of the rolling roll 2 is detected by the speed calculation mechanism 13,
That is, the rolling speed is calculated by the following equation.

V _R = π · D _R · N _R (m / min) Here, D _R is the average diameter (m) of the rolling roll 2, and N _R is the number of revolutions (rpm).

In such a device configuration, the grinding device for the rolling rolls is controlled as described below to carry out grinding.

The whetstone 1 reciprocates in the direction of arrow B within the range of the movement amount L _P by a moving device (not shown). This movement continues even during grinding. Next, pressure oil is sent to the oil supply pipe 7, the hydraulic cylinder 5 operates, the grindstone 1 is pressed against the rolling roll 2, and grinding is started. This grinding is started by the pressure detection mechanism 8
The rotation speed detection mechanism is detected by this detection signal.
12. The pressure control mechanism 9 starts control of the hydraulic cylinder 5 based on the rolling speed detected and calculated by the speed calculation mechanism 13, and controls the pressing force of the grindstone 1 against the rolling roll 2 during grinding as described later. However, the grinding is performed for the time required to obtain the desired grinding amount. The required grinding time is calculated by a necessary time calculator (not shown) by the formula described later, and when the calculated value matches the actual grinding time from the start of grinding by the grinding time calculator (not shown), the signal is used to control the pressure control mechanism 9 actuates the hydraulic cylinder 5 in the opposite direction from the time of pressing,
Release pressing and finish grinding.

Fig. 2 shows the relationship between the grinding amount Gg per revolution of the rolling roll and the rolling speed (peripheral speed of the rolling roll during grinding) V _R obtained from the grinding experiment using the grinding apparatus shown in Fig. 1. Show. The experiment was performed on the grindstones (a) and (b) when the pressing force Fg of the grindstone 1 was constant. The grindstone (a) is a grindstone with a soft bond, and the grindstone (b) is a grindstone with a hard bond. For both grindstones, as the rolling speed V _R increases, the grinding amount Gg per one rotation of the rolling roll tends to decrease,
This tendency is more remarkable as the degree of bonding of the grindstone is harder. The results showed that the tendency did not change even in grinding experiments using grindstones of various bonding degrees or in grinding experiments in which the pressing force Fg was changed.

On the other hand, as described below, it was also found that the grinding amount Gg per revolution of the rolling roll can be controlled to an arbitrary value by the value of the pressing force Fg.

Fig. 3 shows the grinding amount Gg per rolling roll and the rolling speed.
The pressing force Fg at the time of giving an inversely proportional relationship with V _R as shown by the following formula is shown by the relationship with the rolling speed V _R for the above grindstones (a) and (b).

Gg · V _R = C where C is a constant.

If the pressing force Fg is controlled by the value of the rolling speed V _R as shown in FIG. 3 so that the relationship of the above equation is established, the rolling speed V _R and the number of grinding opportunities per unit time are proportional, Rolling speed
The grinding amount G ₁ per unit time becomes constant regardless of V _R , and the desired grinding amount can be accurately controlled by the grinding time. That is, if the grinding amount Gg per one rotation of the roll is inversely proportional to the rolling speed (roll peripheral speed) V _{R as} in the above formula, the grinding amount G ₁ per unit time is constant regardless of the rolling speed V _R. It becomes a value. Therefore, in order to always establish the inverse proportional relationship of the above equation, the rolling speed V _R and the pressing force such that the grinding amount per unit time becomes a certain constant value in advance as shown in (a) and (b) of FIG. It is possible to control the grinding amount G ₁ per unit time to a desired value by obtaining the relationship with Fg by experiments and adjusting the pressing force Fg according to the rolling speed from this relationship.

The required grinding time Tg for obtaining the desired grinding amount is calculated by the following formula.

Here, W _G : Effective grinding width of the grinding wheel 1 (mm) Ga: Desired grinding amount (mm) k: Coefficient Incidentally, as inferred from FIGS. 2 and 3, depending on the selection of the grinding wheel, , If the grinding wheel is selected such that the relationship between the rolling speed V _R and the grinding amount Gg per one rotation of the rolling roll is inversely proportional, the pressing force Fg remains constant regardless of the rolling speed V _R, and grinding control can be performed over time. Is what you can do.

As is clear from the above description, the roll grinding control method and device according to the present invention are not applied only to the rolling roll grinding device shown in FIG. A grinding device, for example, a grindstone having a cylindrical or rod-like shape, or a cloth-like grinding material, can be widely applied regardless of whether or not the grinding material is driven. On the other hand, publicly known methods and means can be applied to the means for pressing the abrasive material against the rolling rolls and various detection and calculation means, and no special one is required. Note that the present invention is not limited to a grinding machine for rolling rolls, a processing line for various strips, for example, a pickling line,
The present invention can be applied to a roll surface grinding device in a plating line, a heat treatment line, etc. <Effects of the Invention> As specifically described above, according to the present invention, it is not necessary to perform advanced arithmetic processing and control. Even when the speed changes online, it is possible to easily and accurately perform roll grinding by grinding control depending on time. In particular, it is possible to provide a roll grinding control method and device which are extremely effective in practice when applied to the grinding of a rolling roll as it is incorporated in a rolling mill.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of a rolling roll grinding device to which the present invention is applied, FIG. 2 is a diagram showing a relationship between a rolling speed V _R and a grinding amount Gg per one rotation of a rolling roll, and FIG. diagram showing the relationship between pressing force Fg to the rolling roll of the grinding wheel with respect to the rolling speed V _R when giving an inverse relationship between the rolling speed rolling roll per revolution of the grinding amount, Figure 4 is the rolling speed V _R It is a figure which shows the example of a pattern of the time change of. In the drawings, 1 is an abrasive, 2 is a rolling roll, 5 is a hydraulic cylinder, 8 is a pressure detection mechanism, 9 is a pressure control mechanism, 12 is a rotation speed detection mechanism, and 13 is a speed calculation mechanism.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location C23G 3/02 9352-4K C25D 7/06 M

Claims (2)

[Claims] 1. A roll grinding control method applied to the processing of a strip traveling while being continuously accelerated and decelerated by a rolling roll, comprising a step of measuring a peripheral speed of the rolling roll, and a grinding amount per one rotation of the rolling roll. By adjusting the pressing force of the abrasive material against the rolling roll according to the measured rolling roll peripheral speed, the grinding amount per unit time of the rolling roll is kept constant so that the relationship is inversely proportional to the rolling roll peripheral speed. The process of controlling and grinding, the process of measuring the time from the start of grinding, and the measured time and the preset grinding time required to obtain the predetermined total grinding amount were compared and found to match. And a step of terminating the grinding at a point of time. 2. A roll grinding control device applied to the processing of a strip traveling while being continuously accelerated and decelerated by a rolling roll, a pressing force detection mechanism for detecting the pressing force of an abrasive material against a rolling roll, and a rolling roll detecting device. The rotation speed detection mechanism that detects the rotation speed, the speed calculation mechanism that calculates the peripheral speed of the rolling roll from the diameter of the rolling roll and the detected rotation speed of the rolling roll, and the grinding time required to obtain the specified total grinding amount Based on the relationship between the required time calculation mechanism, the grinding time calculation mechanism that calculates the actual grinding time that has elapsed since the start of grinding, the pressing force of the abrasive, the grinding amount per rolling roll revolution, and the rolling roll peripheral speed, Based on the detected value of the pressing force of the pressing force detection mechanism and the calculated value of the rolling roll peripheral speed of the speed calculation mechanism, the pressing force of the abrasive is controlled so that the grinding amount per unit time becomes a constant value. Gosuru together, the roll grinding control device calculated value of the actual grinding time is characterized by comprising a pressure control mechanism for releasing the pressing of the abrasive when matching the calculated value of the required grinding time.