JP2001321815A - Method for controlling conveying speed of succeeding rough bar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for controlling the conveying speed of the succeeding rough bar by which the time interval from the start of cutting of the tail end of a preceding rough bar till the cutting of the tip of the succeeding rough bar is enabled is minimized in addition to securing the minimum constrained time which is necessitated from the restriction of the electric and mechanical responsiveness of equipment in a shear for joining. SOLUTION: After determining the time required for the arrival of the tail end till the tail end of the preceeding rough bar 18 reaches the position of the shear 24 for joining and furthermore determing a time required for the arrival of the tip of the succeeding rough bar 12, whose acceleration from a conveying speed to tip cutting speed is started at an acceleration starting position, at the position of the shear 24 for joining, the conveying speed at which the succeeding rough bar 12 is conveyed to the acceleration starting position is adjusted so that the time required for the arrival of the tip and the time required for the arrival of the tail end coincides with the operating time of the shear 24 for joining from the start of cutting of the tail end of the preceding rough bar 18 to a time when the cutting of the tip of the succeeding rough bar 12 is enabled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for joining a tail end of a leading coarse bar and a leading end of a following coarse bar in a continuous hot rolling step, depending on the traveling speed of the preceding coarse bar. The present invention relates to a method for controlling the transport speed of a subsequent coarse bar so that the time interval from the start of tail end cutting to the time when the leading end of the following coarse bar can be cut is minimized.

[0002]

2. Description of the Related Art In a continuous hot rolling process, a trailing coarse bar running after a preceding coarse bar running ahead of a finishing rolling mill is driven to catch up with the trailing coarse bar. The end and the leading end of the subsequent coarse bar were abutted and joined to form an integrated rough bar for finish rolling. Also, when the leading coarse bar catches up the trailing coarse bar and the tail end of the leading coarse bar and the leading end of the trailing coarse bar are abutted and joined, a joining shear is used to join the tail end of the leading coarse bar with the trailing coarse bar. The ends of the coarse bars were cut to form end faces that were easy to join.

When the tail end of the leading coarse bar and the leading end of the following coarse bar are joined on the joining bogie, the traveling distance of the leading coarse bar is limited because the traveling section of the joining bogie is limited. It is important to keep it short. Therefore, when the tail end of the leading coarse bar is cut and the leading end of the following coarse bar is cut, it is easier for the leading coarse bar to catch up with the trailing coarse bar when approaching as close as possible. It was necessary to convey the row coarse bar as close as possible to the preceding coarse bar.

[0004]

However, since the tail end of the leading coarse bar and the tip of the subsequent coarse bar are cut by one joining shear, the electrical and mechanical responsiveness of the joining shear is reduced. Due to restrictions, a predetermined time interval is required from the start of cutting the tail end of the preceding coarse bar to the end of the trailing coarse bar being cuttable. In particular, due to the hardness of the rough bar that is the object to be cut, the shear for joining is designed to have large inertia, so it takes time to accelerate and decelerate the blade,
A predetermined time was required from the start of cutting until the next cut became possible. For this reason, if the transport speed of the subsequent coarse bar is high and the subsequent coarse bar is transported too close to the preceding coarse bar, there is a problem that the leading end of the subsequent coarse bar cannot be cut.

In addition, the conveying speed of the subsequent coarse bar is too slow,
If the trailing coarse bar is transported too far from the preceding coarse bar,
In the case of a coarse bar that takes time to catch up with the leading coarse bar and takes a long time to join, the joining does not end within the traveling section of the joining bogie, and the joining rough bar in an incomplete joining state is finished by a rolling mill Will be bitten by. When finish-rolling a rough bar with incomplete joining, there is a problem that the rough bar is cut during the finish rolling. The present invention has been made in view of the above circumstances, and cuts the tail end of the leading coarse bar while minimizing the time required due to the restriction of electrical and mechanical equipment responsiveness of the joining shear. It is an object of the present invention to provide a method of controlling the transport speed of a subsequent coarse bar that can minimize the time interval from the start of the process to the time when the leading end of the subsequent coarse bar can be cut.

[0006]

According to the present invention, there is provided a method for controlling a conveying speed of a trailing coarse bar according to the present invention. In the method of controlling the transport speed of a subsequent coarse bar in the case where the leading end of the subsequent coarse bar is cut by the joining shear and then abutted to each other and then joined, the tail end of the preceding coarse bar is positioned at the position of the joining shear. Calculate the time required to reach the tail end to reach the tip, and further, start the acceleration from the transport speed to the tip cut speed at the acceleration start position, where the tip of the following coarse bar reaches the position of the joining shear. Finding the required time, the difference between the required time to reach the leading end and the required time to reach the tail end is from the start of cutting the tail end of the preceding coarse bar until the leading end of the following coarse bar can be cut. Operating time of the joining shear As matching, adjusting the conveying speed for conveying the trailing coarse bar to the acceleration starting position.

[0007] From the start of cutting the tail end of the preceding coarse bar to the point where the leading end of the following coarse bar can be cut,
The blade of the joining shear accelerates from the cutting standby position to the same speed as the traveling speed of the preceding coarse bar, cuts the tail end of the preceding coarse bar, then decelerates to the cutting standby position, stops and waits. Perform the operation. On the other hand, the response speed of the above-described series of operations of the blade has a limit due to mechanical and electrical equipment restrictions such as the inertia of the joining shear being designed to have a large inertia due to the hardness of the object to be cut. For this reason, a series of operations of accelerating from the cutting standby position to the traveling speed of the preceding coarse bar, cutting the tail end of the preceding coarse bar, then decelerating and returning to the cutting standby position and waiting, that is, the tail end of the preceding coarse bar In the operation time of the joining shear from the start of the cutting to the point where the leading end of the following coarse bar can be cut, there is a time interval that must be ensured.

[0008] The operating time of the joining shear until the blade of the stopped joining shear accelerates, cuts the tail end of the preceding coarse bar, decelerates and returns to the cutting standby position is determined by the traveling speed of the preceding coarse bar. Is determined, it can be set within the range of the electrical and mechanical response speed of the joining shear.
By setting the electrical and mechanical response speed of the joining shear to the maximum value, the operating time of the joining shear can be minimized, and this minimum operating time is the time that must be secured. . Therefore, by setting the operation time of the joining shear to the minimum time (hereinafter referred to as the minimum idle time), the blade of the joining shear can return to the cutting standby position and wait, and at the same time, move to the cutting operation of the subsequent coarse bar. Becomes

The operating time of the joining shear is defined as the minimum idle time, that is, the blade of the joining shear starts cutting the tail end of the preceding coarse bar, returns to the cutting standby position and waits for the subsequent coarse bar at the same time. In order to be able to shift to the cutting operation, the leading end of the following coarse bar should reach the joining shear position after the minimum idle time has passed since the tail end of the preceding coarse bar reached the position of the joining shear. In other words, the time may be set to match the required time to reach the tip.

The trailing coarse bar that has been unwound from the coil box and conveyed is accelerated to a predetermined leading edge cutting speed when the leading end of the trailing coarse bar is cut by the joining shear. At this time, the acceleration start position at which the subsequent coarse bar starts to accelerate and the joining shear position are fixed on the equipment, and the acceleration rate of the speed is also a constant value depending on the equipment capacity. Therefore, if the transport speed of the following coarse bar reaching the acceleration start position is determined, the time required for the leading end of the following coarse bar to reach the joining shear position from the acceleration start position can be uniquely determined.

Therefore, after the minimum idle time after the tail end of the preceding coarse bar reaches the position of the joining shear, the leading end of the succeeding coarse bar reaches the position of the joining shear and is unwound from the coil box. It is necessary to adjust the transport speed when transporting the subsequent coarse bar that has been transported to the acceleration start position. Since the speed of the preceding coarse bar changes depending on the finish rolling conditions, the time required for the tail end of the preceding rough bar to reach the position of the joining shear also changes during finish rolling. For this reason, the tail end of the preceding coarse bar is always detected to predict the cutting start time, and the leading end of the following coarse bar is also always detected. It is necessary to control whether to reach the shear position, that is, the time required to reach the tip.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. Here, FIG. 1 is a conceptual diagram of a downstream coarse bar transport speed control apparatus to which the downstream coarse bar transport speed control method according to one embodiment of the present invention is applied, and FIG. 2 is an embodiment of the present invention. And FIG. 3 is a schematic diagram illustrating a control process of the cut idle control speed by the following coarse bar transfer speed control method. As shown in FIG. 1, the trailing coarse bar transport speed control equipment 10 to which the trailing coarse bar transport speed control method according to one embodiment of the present invention is applied, Gradle roll 13 and table roll 14 for controlling the transport speed of coarse bar 12, tip detection sensor 15 for detecting the tip of trailing coarse bar 12, and the fact that the tip of trailing coarse bar 12 has reached the acceleration start position. An acceleration start detection sensor 16 for detecting, an acceleration pinch roll 17 for accelerating the leading end of the subsequent coarse bar 12 reaching the acceleration start position, a tail end detection sensor 19 for detecting the tail end of the preceding coarse bar 18, and a grade. Roll drive device 20, table roll drive device 21, pinch roll drive device 22 for acceleration, front end detection sensor 15, acceleration start detection sensor 16, and tail end detection sensor Function of controlling the transport speed of the trailing coarse bar 12 has a control unit 23 provided from the 9 signal. Hereinafter, these will be described in detail.

Grade roll 13 and table roll 1
Reference numeral 4 denotes a device that unwinds the subsequent coarse bar 12 that has been rough-rolled and wound into the coil box 11 from the coil box 11 and conveys it to a finishing rolling mill (not shown) at a specified predetermined conveying speed. When the leading end of the trailing coarse bar 12 reaches the position of the leading end detection sensor 15 and the leading end of the trailing coarse bar 12 is detected, the control device 23 sends the Gradle roll driving device 2.
0, a driving command signal is output to the table roll driving device 21. For this reason, the rotation speed of the grade roll 13 and the table roll 14 changes, and the conveyance speed of the following coarse bar 12 changes. The tip detection sensor 15 is a non-contact type detection sensor, and for example, an optical sensor can be used.

When the acceleration start detecting sensor 16 detects that the leading end of the following coarse bar 12 has reached the acceleration start position, the control device 23 sends a driving command signal to the acceleration pinch roll driving device 22. Is output, and the accelerating pinch roll 17 starts driving, and accelerates the following coarse bar 12 to a specified predetermined tip cutting speed (for example, 90 m / min). The acceleration start detection sensor 16 is a non-contact type detection sensor, and for example, an optical sensor can be used.

The control device 23 determines a transport speed for transporting the trailing coarse bar 12 to the acceleration start position, that is, a cut idle control speed, based on signals from the leading edge detection sensor 15 and the tail edge detection sensor 19. This is a device for outputting a drive command signal to the gradual roll drive device 20 and the table roll drive device 21 so that The control device 23 includes a following coarse bar calculation unit, a preceding coarse bar calculation unit,
A transport speed calculation unit. The following coarse bar calculation unit
According to the signal from the tip detection sensor 15, the following coarse bar 12
Is detected, and the travel time of the trailing coarse bar 12 until the leading end of the trailing coarse bar 12 reaches the position of the joining shear 24 is calculated.

The leading coarse bar calculation unit is a tail end detection sensor 1
9 to detect the tail end of the preceding coarse bar 18 and calculate the time required for the tail end of the preceding coarse bar 18 to reach the position of the joining shear 24, that is, the time required to reach the tail end. In consideration of the minimum idle time, which is the minimum operation time of the joining shear 24 from when the tail end of the joining shear 24 begins to be cut by the joining shear 24 until the tip of the following coarse bar 12 can be cut by the joining shear 24, The time from when the tail end of the preceding coarse bar 18 is detected to when the tail end of the preceding coarse bar 18 is cut and the tip of the succeeding coarse bar 12 can be cut (hereinafter referred to as target cut idle time).
Is calculated.

The transport speed calculating section determines the leading end of the following coarse bar 12 from the running time of the following coarse bar 12 obtained by the following coarse bar calculating section and the target cut idle time obtained by the preceding coarse bar calculating section. The time required to reach the acceleration start position is obtained, and the transport speed required for the leading end of the following coarse bar 12 to reach the acceleration start position, that is, the cut idle control speed, is calculated based on the required time. The control device 23 includes, for example, a calculation unit that performs various calculations and each drive device 2.
A configuration using a sequencer having both functions of an output unit for outputting output signals to 0, 21, and 22 can be adopted.

FIG. 2 is a flowchart showing a method of controlling the transport speed of the following coarse bar according to an embodiment of the present invention. Hereinafter, the method of controlling the transport speed of the trailing coarse bar of the present invention will be described in detail with reference to this flowchart.
When the transport speed control equipment 10 for the subsequent coarse bar starts,
The leading end detection sensor 15 detects the leading end of the trailing coarse bar 12 (step S1). It is determined whether the leading end of the trailing coarse bar 12 exists in the cut idle control section that controls the transport speed of the trailing coarse bar 12. Judge (Step S
2). If it is determined that the leading end of the following coarse bar 12 does not exist in the cut idle control section, the leading end detection sensor 1
5 detects the leading end of the following coarse bar 12 (step S5).
Return to 1).

If the leading end of the trailing coarse bar 12 is detected and it is determined that it has entered the cut idle control section,
The positions of the tail end of the preceding coarse bar 18 and the front end of the following coarse bar 12 are calculated by the detection by the front end detection sensor 15 and the tail end detection sensor 19 (step S3). When the tail end of the preceding coarse bar 18 is detected by the tail end detection sensor 19, the elapsed time from the detection of the tail end of the preceding coarse bar 18 is detected because the preceding rough bar 18 is finish-rolled at a predetermined speed. Is used to determine the current tail end position of the preceding coarse bar 18. Similarly, when the leading end of the trailing coarse bar 12 is detected, the trailing coarse bar 12 is being transported to the finishing rolling mill at a predetermined transport speed. Using the elapsed time, the current tip position of the following coarse bar 12 is determined.

Subsequently, the leading end of the following coarse bar 12 is detected by the acceleration start detecting sensor 16 (step S).
4) It is determined whether the leading end of the following coarse bar 12 is present in the cut idle control section (step S5). When the leading end of the trailing coarse bar 12 is detected by the acceleration start detection sensor 16, the leading end of the trailing coarse bar 12 has passed through the cut idle control section. In order to detect the leading end, the process returns to the leading end detection state of the trailing coarse bar by the leading end detection sensor 15 (step S1).

If the leading end of the following coarse bar 12 is not yet detected by the acceleration start detection sensor 16 and it is determined that the leading end of the following coarse bar 12 is within the cut idle control section, the following coarse bar 12 is Calculates the travel time from when the leading end of the following coarse bar 12 reaches the position of the joining shear 24 from the acceleration start position when it is assumed that the leading end of the following coarse bar 12 has been transported to the acceleration start position and accelerated to the leading end cut speed at the transport speed of (Step S6). Here, the pinch roll 17 for acceleration
The acceleration rate is determined by the motor capability of the pinch roll for acceleration and becomes a predetermined value. On the other hand, since the tip cutting speed depends on the finish rolling speed of the preceding rough bar 18, the speed is specified by the process management computer that manages the finish rolling process. Also, the distance between the acceleration start position and the position of the joining shear 24 is uniquely determined by the finishing rolling equipment,
Once the transport speed of the succeeding coarse bar 12 transported to the acceleration start position is determined, the time required to accelerate from the transport speed to the leading edge cutting speed and the time from when the leading edge cutting speed is reached to the position of the joining shear 24 are reached. Is determined uniquely.

Due to the restriction of the electrical and mechanical response speed of the joining shear 24, the minimum idle time which is the minimum operation time of the joining shear 24 is uniquely determined when the traveling speed of the preceding coarse bar 18 is determined. Is done. For this reason, the minimum idle time is specified by the process management computer that manages the finish rolling process (step S7).

Tail end detection sensor 19 and joining shear 24
Since the position distance is uniquely determined by the finishing rolling equipment, when the tail end detection sensor 19 detects the tail end of the leading coarse bar 18, the leading rough bar 18 is finish-rolled at a predetermined speed. The required time from when the tail end of the preceding rough bar 18 is detected to when it reaches the position of the joining shear 24, that is, the time required to reach the tail end, is determined. Further, the cutting time for cutting the tail end of the preceding rough bar 18 by the joining shear 24 can be determined from the finish rolling speed of the preceding rough bar 18. Accordingly, the time from when the tail end of the preceding coarse bar 18 is detected to when the tail end of the preceding coarse bar 18 is cut and the tip of the succeeding coarse bar 12 can be cut, that is, the time required to reach the tail end and the minimum idle time Can be calculated (step S8).

When it is desired to control the time interval from the start of the cutting of the tail end of the preceding coarse bar 18 to the end of the following coarse bar to be cuttable to the minimum idle time, the position of the leading end of the following coarse bar 12 is controlled. When the tail end position of the preceding coarse bar 18 is simultaneously grasped, the traveling time from the current position to the acceleration start position of the leading end of the following coarse bar 12 and the travel time from the acceleration start position to the welding shear 24 position are obtained. , That is, the time required to reach the front end, must be equal to the target cut idle time.

From the above, when the condition 1: the time required to reach the tail end + the minimum idle time = the target cut idle time, the condition 2: the time required to reach the front end = the target cut idle time is satisfied, the time required to configure the time required to reach the front end is obtained. Both the travel time from the current position to the acceleration start position of the row coarse bar 12 and the travel time from the acceleration start position to the joining shear 24 position are determined by the following coarse bar 1.
Since the transfer speed depends on the transfer speed of No. 2, the transfer speed at which the trailing coarse bar 12 reaches the acceleration start position is uniquely determined. The determined transport speed of the subsequent coarse bar 12 is defined as a cut idle control speed. A drive command signal is output from the control device 23 to the grade roll drive device 20 and the table roll drive device 21 so that the cut idle control speed is obtained (step S9).

The running speed of the leading coarse bar 18 is the finish rolling.
Changes inside. For this reason, the tail end of the leading coarse bar 18 is detected.
After that, the tail end of the preceding coarse bar 18 can be cut.
The time at is fluctuating. Therefore, the target cut eye
Since the time varies, for example, steps every 50 ms
Repeat the operations from S1 to S9 to cut
The idle control speed is constantly adjusted. Then, in FIG.
Specific control process of cut idle control speed based on
explain. The tip of the trailing coarse bar 12 is a tip detection sensor
15, the cut idle control is started.
It is. (1) In the first cut idle control, the following coarse bar
12 is the current transport speed V ₀ Transported to the acceleration start position
The tip cutting speed V which is accelerated and is a predetermined constant speed_cut 
, The tail end position of the preceding coarse bar 18 is considered.
The target cut idle time is determined with due consideration. Next, this eye
Cut idle control speed for standard cut idle time
V₁ Is calculated, and the transport speed of the succeeding coarse bar 12 is set to V₀ To V
₁ Adjust to

(2) At the time when the second cut idle control is started, the leading end of the following coarse bar 12 and the tail end of the preceding coarse bar 18 have moved to the finishing mill side, and the target cut idle time Is changing. Therefore, the target cut idle time is calculated based on the cut idle control speed V ₁ adjusted by the first cut idle control, and the cut idle control speed V ₂ for this target cut idle time is calculated. 12 transfer speeds V ₁
Adjusted to V ₂ from. (3) As described above, the target cut idle time is sequentially obtained in accordance with the position change between the leading end of the following coarse bar 12 and the tail end of the preceding coarse bar 18, and the cut idle control speed for this target cut idle time is calculated. By sequentially calculating, the transport speed of the succeeding coarse bar 12 is adjusted to be the latest cut idle control speed. The cut idle control ends when the leading end of the following coarse bar 12 is detected by the acceleration start detection sensor 16, and the following coarse bar 12 is moved to the cut idle control speed V _n.
To the tip cutting speed _Vcut .

The embodiment of the present invention has been described above.
The present invention is not limited to this embodiment.
For example, although an optical sensor is used for the leading end detection sensor, the acceleration start detection sensor, and the tail end detection sensor, an ultrasonic sensor may be used. Although a sequencer was used as the control device, a microcomputer can also be used.

[0029]

According to the method for controlling the conveying speed of the following coarse bar, the time required for the tail end of the preceding coarse bar to reach the position of the joining shear is determined.
In the acceleration start position, the acceleration from the transport speed to the tip cutting speed is started, and the leading end reaching time required for the leading end of the subsequent coarse bar to reach the position of the joining shear is determined. Move the following coarse bar to the acceleration start position so that the difference matches the operating time of the joining shear from the start of the tail end of the preceding coarse bar until the leading end of the following coarse bar can be cut. Since the transport speed for transport is adjusted,
It is possible to cut the tail end of the leading coarse bar and the tip of the following coarse bar at the minimum time interval in consideration of equipment restrictions, and the trailing coarse bar can reliably catch up with the leading coarse bar.
The tail end of the preceding coarse bar and the front end of the following coarse bar can be securely joined.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a trailing coarse bar transport speed control facility to which a trailing coarse bar transport speed control method according to an embodiment of the present invention is applied.

FIG. 2 is a flowchart showing a method of controlling a transport speed of a subsequent coarse bar according to an embodiment of the present invention.

FIG. 3 is a schematic diagram illustrating a control progress of a cut idle control speed by a method of controlling a conveying speed of a trailing coarse bar according to an embodiment of the present invention.

[Explanation of symbols]

10: transfer speed control equipment, 11: coil box, 1
2: trailing coarse bar, 13: gradle roll, 14: table roll, 15: tip detection sensor, 16: acceleration start detection sensor, 17: acceleration pinch roll, 18: leading coarse bar, 19: tail end detection sensor, 20: Gradle roll drive, 21: Table roll drive, 22:
Acceleration pinch roll drive device, 23: control device, 24:
Joining shear

Claims (1)

[Claims] 1. A tail end of a preceding coarse bar traveling at a finish rolling speed and a leading end of a following coarse bar traveling at a predetermined tip cutting speed are cut by a joining shear, and then contacted with each other to be joined. In the transfer speed control method of the subsequent coarse bar in the case of, the tail end arrival time required until the tail end of the preceding coarse bar reaches the position of the joining shear is obtained, and further, the transfer speed is calculated from the transfer speed at the acceleration start position. The leading end of the trailing coarse bar that starts accelerating to the leading end cutting speed determines the leading end arrival time required to reach the position of the joining shear, and the difference between the leading end arrival time and the tail end arrival time is calculated. Accelerating the subsequent coarse bar so as to coincide with the operation time of the joining shear from the start of cutting the tail end of the preceding coarse bar until the leading end of the subsequent coarse bar can be cut. Said transport to transport to start position A method for controlling a conveying speed of a subsequent coarse bar, comprising adjusting a speed.