KR101167172B1

KR101167172B1 - Method for calculating length and width in rolling process

Info

Publication number: KR101167172B1
Application number: KR20100017478A
Authority: KR
Inventors: 강기수; 김동일
Original assignee: 현대제철 주식회사
Priority date: 2010-02-26
Filing date: 2010-02-26
Publication date: 2012-07-24
Also published as: KR20110098057A

Abstract

The present invention relates to a method for calculating the length and width of a plate in a rolling process of calculating the length and width of a cold state plate by applying a thermal expansion coefficient differently according to the temperature of the hot state plate in the rolling process, the length and width of the hot state plate Sensing the temperature, calculating a coefficient of thermal expansion at the temperature of the hot state sheet; And calculating the length and width of the cold state sheet by applying a coefficient of thermal expansion to the length and width of the hot state sheet.

Description

METHODS FOR CALCULATING LENGTH AND WIDTH IN ROLLING PROCESS}

The present invention relates to a rolling process, and more particularly, to a method of calculating the length and width of a plate in a rolling process of calculating a length and width of a cold state sheet by applying a thermal expansion coefficient differently according to the temperature of the hot state sheet in the rolling process. It is about.

In general, the hot rolling process is a process of producing a product of a desired specification by rolling a plate through a rolling mill. The hot rolling process is configured to transfer plate materials such as semi-finished products along the process line using a conveyor or the like.

In the hot rolling process, the plate is heated to a constant temperature in the furnace before being blown into the rolling mill for smooth rolling. In this way, when the plate is blown from the heating furnace, the rolling mill adjusts the reduction amount according to the plate is injected to produce the desired product. Thereafter, the cutter cuts the plate, and places the cut plate on the loading rack.

The above technical configuration is a background art for helping understanding of the present invention, and does not mean a conventional technology well known in the art.

The present invention calculates the length and width of the cold state sheet by applying a different coefficient of thermal expansion according to the temperature of the hot state sheet detected in the hot state, thereby improving the cold state sheet length and width measurement accuracy of the plate in the rolling process To provide a method for calculating the length and width of the object.

Another object of the present invention is to improve the accuracy in calculating the length and width of the cold state sheet to minimize the margin in the initial blade design to improve the error rate.

The configuration of the present invention, which is invented to achieve the above-described object, is as follows.

Method for calculating the length and width of the plate in the rolling process of the present invention comprises the steps of sensing the length and width and temperature of the hot state plate; Calculating a coefficient of thermal expansion at the temperature of the hot state sheet; And calculating the length and width of the cold state plate by applying the thermal expansion coefficient to the length and width of the hot state plate.

In the present invention, the temperature is characterized in that divided into three temperature bands according to the phase transformation temperature of the hot state plate.

In the present invention, the thermal expansion coefficient is characterized by calculating using the thermal expansion coefficient slope of each of the temperature band and the temperature of the hot state plate.

The present invention can improve the accuracy in calculating the length and width of the cold state plate, and can improve the error rate by minimizing the margin at the initial blade design.

1 is a block diagram of a device for calculating the length and width of a plate in a rolling process according to an embodiment of the present invention.
Figure 2 is a flow chart of the length and width calculation method of the plate in the rolling process according to an embodiment of the present invention.
3 is a view showing a thermal expansion coefficient for each temperature band according to the phase transformation temperature of the plate according to an embodiment of the present invention.

Hereinafter, the length and width calculation method of the plate in the rolling process according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this process, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to a user's or operator's intention or custom. Therefore, the definitions of these terms should be made based on the contents throughout the specification.

1 is a block diagram of a device for calculating the length and width of a plate in a rolling process according to an embodiment of the present invention.

Device for calculating the length and width of the plate in the rolling process according to an embodiment of the present invention, as shown in Figure 1, the length sensing unit 10, the width sensing unit 20, the temperature sensing unit 30 and the control unit ( 40).

The length sensing unit 10 detects the length of the hot state plate, and the width detecting unit 20 detects the width of the hot state plate.

The length detecting unit 10 and the width detecting unit 20 may use various methods such as a method using a photo sensor, a method using a laser, a method using a camera, and a method using a photo sensor and a camera together.

Here, since the length and width of the plate using the length sensing unit 10 and the width detecting unit 20 can be easily implemented by those skilled in the art, a detailed description thereof will be omitted.

The temperature detector 30 is installed at the exit side of the hot rolling mill (not shown) to sense the temperature of the hot state plate. Usually, a hot rolling mill is provided with a several rolling stand, and detects the temperature of a board | plate material at the entrance side and exit side of this rolling stand, respectively.

The controller 40 calculates the length and width of the cold state plate when the length and width of the hot state plate detected in the hot state by the length detector 10 and the width detector 20 are input. To this end, the control unit 40 stores various data necessary for calculating the length and width of the cold state sheet and mounts a program necessary for the calculation.

Figure 2 is a flow chart of the length and width calculation method of the plate in the rolling process according to an embodiment of the present invention, Figure 3 is a view showing the thermal expansion coefficient for each temperature band according to the phase transformation temperature of the plate according to an embodiment of the present invention to be.

The length detecting unit 10 and the width detecting unit 20 detect the length and width of the hot state plate conveyed through the roller table of the hot rolling mill and input the same to the control unit 40. In addition, the temperature sensing unit 30 detects the temperature of the hot state plate at the exit side of the hot rolling mill (S10) and inputs it to the control unit 40.

When the temperature of the hot state plate is input from the temperature sensing unit 30, the control unit 40 calculates a thermal expansion coefficient at the temperature of the hot state plate (S20).

Typically, the metal undergoes expansion, contraction and expansion depending on the phase transformation temperature. That is, the coefficient of thermal expansion increases, decreases and increases with the temperature of the plate.

Accordingly, the controller 40 calculates the coefficient of thermal expansion at the corresponding temperature by dividing the temperature of the hot state plate detected by the temperature sensor 30 in the hot state into three temperature bands according to the phase transformation temperature of the metal.

3 shows thermal expansion at a first temperature band Tm ≦ T1, a second temperature band T1 ≦ Tm <T2, a third temperature band Tm> T2, and respective temperatures according to the temperature Tm of the hot state sheet. The coefficients are shown.

The thermal expansion coefficient k1 in the first temperature band increases in thermal expansion coefficient k1 until the temperature reaches the first temperature T1. The thermal expansion coefficient k2 in the second temperature band decreases until the temperature reaches the second temperature T2 after the temperature exceeds the first temperature T1. It can be seen that the coefficient of thermal expansion k3 in the third temperature range increases after exceeding the second temperature T2.

The thermal expansion coefficients k1, k2, and k3 are calculated using the thermal expansion coefficient slope of each temperature band, the temperature of the hot state plate detected by the temperature sensing unit 30, and the thermal expansion coefficient offset value of each temperature band.

That is, the method of calculating the thermal expansion coefficient k1 in the first temperature band is as follows.

k1 = a1 × Tm + b1

Here, k1 is the coefficient of thermal expansion calculated using the first temperature band, a1 is the slope of the coefficient of thermal expansion of the first temperature band, Tm is the temperature of the hot state plate detected by the temperature sensing unit 30, b1 is The offset value of the coefficient of thermal expansion in the first temperature band is a constant.

The method of calculating the coefficient of thermal expansion k2 in the second temperature band is as follows.

k2 = a2 × Tm + b2

Here, k2 is the coefficient of thermal expansion calculated using the second temperature band, a2 is the slope of the coefficient of thermal expansion of the second temperature band, Tm is the temperature of the hot state plate detected by the temperature sensing unit 30, b2 is The offset value of the coefficient of thermal expansion in the second temperature band is a constant.

The method of calculating the thermal expansion coefficient k3 in the third temperature band is as follows.

k3 = a3 × Tm + b3

Here, k3 is the coefficient of thermal expansion calculated using the third temperature band, a3 is the slope of the coefficient of thermal expansion of the third temperature band, Tm is the temperature of the hot state plate detected by the temperature sensor 30, b3 is The offset value of the coefficient of thermal expansion in the third temperature band is a constant.

That is, the thermal expansion coefficients k1, k2, and k3 can know the thermal expansion coefficients k1, k2, and k3 at the detected temperature by using the temperature of the hot state plate detected by the temperature sensing unit 30. .

As described above, when the thermal expansion coefficients k1, k2, and k3 are calculated using the respective temperature bands, the length and width of the cold state board are calculated using the thermal expansion coefficients k1, k2 and k3 (S30).

The length of the cold state plate is the thermal expansion coefficient (k1, k2, k3) and the temperature sensing unit 30 calculated by using the length Lo and the respective temperature bands detected by the length sensing unit 10 in the hot state. Calculate using the temperature of the hot state plate detected by.

In addition, the width of the cold state plate is the thermal expansion coefficient (k1, k2, k3) and the temperature in the hot state calculated using the width (Wo) of the plate detected by the width sensor 20 in the hot state and each temperature band It calculates using the temperature of the board | plate material detected by the detection part 30.

When the temperature sensed by the temperature sensing unit 30 is the first temperature band, a method of calculating the length Lo of the cold state sheet is as follows.

Lo = Lm × (1+ (k1 × (25-Tm)))

Here, Lo is the length of the cold state plate, Lm is the length of the hot state plate detected by the length sensing unit 10, k1 is the coefficient of thermal expansion calculated using the first temperature band, Tm is the temperature sensing unit The temperature of the hot state plate detected by 30.

When the temperature sensed by the temperature sensing unit 30 is the second temperature band, a method of calculating the length Lo of the cold state sheet is as follows.

Lo = Lm × (1+ (k2 × (25-Tm)))

Here, Lo is the length of the cold state plate, Lm is the length of the hot state plate detected by the length sensing unit 10, k2 is the coefficient of thermal expansion calculated using the second temperature band, Tm is the temperature sensing unit The temperature of the hot state plate detected by 30.

When the temperature sensed by the temperature sensing unit 30 is the third temperature band, a method of calculating the length Lo of the cold state sheet is as follows.

Lo = Lm × (1+ (k3 × (25-Tm))

Here, Lo is the length of the cold state plate, Lm is the length of the hot state plate detected by the length sensing unit 10, k3 is the coefficient of thermal expansion calculated using the third temperature band, Tm is the temperature sensing unit The temperature of the hot state plate detected by 30.

On the other hand, the width (Wo) of the cold state board is similar to the above-mentioned length, and can be obtained only by substituting the width for the length of the hot state board.

That is, the width Wo of the cold state plate in each temperature range is as shown in the following equation.

Wo = Wm × (1+ (k1 × (25-Tm))

Wo = Wm × (1+ (k2 × (25-Tm)))

Wo = Wm × (1+ (k3 × (25-Tm)))

Here, Wo is the width of the cold state plate, Wm is the width of the hot state plate detected by the width sensing unit 20, k1, k2, k3 is thermal expansion calculated using the first, second, third temperature band The coefficient, Tm, is the temperature of the hot state plate detected by the temperature sensor 30.

Accordingly, the length Lo and the width W o of the cold state plate are calculated using the temperature of the hot state plate and the coefficient of thermal expansion at this temperature, so that the length Lo and the width W o of the cold state plate are calculated. Its accuracy can be improved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, I will understand. Therefore, the true technical protection scope of the present invention will be defined by the claims below.

10: length detector
20: width detection unit
30: temperature sensing unit
40:

Claims

Sensing the length, width and temperature of the hot state sheet;
Calculating a coefficient of thermal expansion at the temperature of the hot state sheet; And
Calculating the length and width of the cold state sheet by applying the coefficient of thermal expansion to the length and width of the hot state sheet.

The method of claim 1, wherein the temperature is divided into three temperature bands according to the phase transformation temperature of the hot state sheet.

The method of claim 2, wherein the coefficient of thermal expansion is calculated using a slope of thermal expansion coefficient of each of the temperature bands and a temperature of the hot state plate.