JPH01118312A - Controller for edge heater - Google Patents

Abstract

PURPOSE:To improve the control accuracy of an edge temperature by controlling the output of an edge heater according to the deviation of a measured sheet thickness and moving the position of the edge heater in the width direction of band steel according to the difference between measured temperatures at both edge parts. CONSTITUTION:A measuring roll 12 and a thickness gauge 13 are provided on the front stage side of a preheating room 2 and a traveling mechanism 4-1 having a motor 4-2 is arranged at the edge heater 4. When a skelp 1 travels, a measuring roll 12 outputs a speed detecting signal of a number of pulses corresponding to traveling speed and the thickness gauge 13 measures the thickness of the skelp 1 and inputs it into the main controller 15. Hereby, the output of the edge heater 4 is controlled according to the deviation of sheet thickness and further the position of the heater 4 is moved in a width direction according to the difference of temperature between the edges. Since heating is controlled according to the thickness of the sheet and at the same time the temperatures of both edge parts balance, the controlling accuracy of the temperatures at the edge parts is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an edge heater control device for heating the edge portion of a skelp (steel band), which is applied to a forge-welded pipe manufacturing system.

[Conventional technology]

FIG. 13 is a configuration diagram of a forge-welded pipe manufacturing system, in which the skelp 1 passes through a preheating chamber 2 and a heating furnace 3, and is composed of an upper coil 4a and a lower coil 4b, and an edge heater that heats both edges of the skelp 1 by the skin effect. Sent to 4th, and then forged welding! ! It is scheduled to be sent to the 15th. By the way, since the part corresponding to the seam of Skelp 1 corresponds to the off-gauge part of the hot rolling process, the thickness variation is large, which causes a decrease in the temperature of both edges. For this reason, the quality of the joint portion of the manufactured forge-welded pipe is significantly degraded. The edge heater 4 has the function of eliminating such a temperature drop at the edge portion, and a temperature measuring device 6 using a linear array is arranged on the downstream side of the edge heater 4.
The squelp temperature distribution detection signal output from the heater tJ
The information is sent to the control section 7. Note that the linear array is composed of a large number of silicon photodiodes and a scanning section that reads out accumulated charges. Therefore, the temperature distribution of Skelp 1 measured by the temperature measuring device 6 is
The heater control unit 7 controls the output of the edge heater 4 according to the temperature distribution.

On the other hand, there is a temperature difference E between the edges A and Skelp 1 as shown in FIG. 14, resulting in an imbalance. If the two edge temperatures are unbalanced as described above, the quality of the manufactured forge-welded pipe will be degraded, so efforts are being made to eliminate this unbalanced edge temperature.

That is, the squelp temperature distribution measured by the temperature measuring device 6 is monitored on a monitor television, and the position of the edge heater 4 is manually adjusted in the width direction (a) of the squelp 1 as shown in FIG. 15 according to the squelp temperature distribution. I'm moving it with that.

[Problem that the invention seeks to solve]

As described above, the output and position of the edge heater 4 are controlled so as not to lower the temperature of both edge portions and to prevent imbalance, but with such technology it is difficult to control the edge temperature to an appropriate temperature. Measures against this are insufficient. Furthermore, since the edge heater 4 is manually moved in order to balance the temperatures of both edges, the adjustment accuracy varies due to individual differences among workers.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an edge heater control device that can control the temperature of a steel strip to an appropriate temperature and balance both edge temperatures with high accuracy.

[Means for solving problems]

The present invention is an edge heater control device that heats both edges of a steel strip heated in a preheating chamber heating furnace and sends this steel strip to a forge welding machine. A thickness gauge, a heater output control means for tracking the plate thickness measured by the thickness gauge to the edge heater and controlling the output of the edge heater according to the plate thickness, and a heater output control means for controlling the output of the edge heater in accordance with the plate thickness; and edge heater position control means for moving the position of the edge heater in the width direction of the steel strip in accordance with the temperature difference between both edges measured by the edge temperature measuring device. This is an edge heater control device that attempts to achieve the above object.

[Effect]

By providing such a means, the heater output control means tracks the measured value of the thickness gauge placed at the front stage of the preheating furnace to the edge heater, and adjusts the output of the edge heater according to the plate thickness. In addition, the edge heater position control means moves the position of the edge heater in the width direction of the steel strip in accordance with the temperature difference between both edges measured by an edge temperature measuring device disposed on the downstream side of the edge heater.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. Note that the same parts as in FIG. 13 are given the same reference numerals, and detailed explanation thereof will be omitted.

FIG. 1 is an overall configuration diagram of an edge heater control device applied to a forge-welded pipe manufacturing system. Two pinch rolls 10 and 11 are arranged on the front side of the preheating chamber 2, and a measuring roll 12 and a thickness gage 13 are arranged between these pinch rolls 10 and 11. The measuring roll 12 outputs a speed detection signal of the number of pulses corresponding to the running speed of the squelp 1, and this speed detection signal is sent to the main control section 15 through the l10 (input/output) boat 14. ing. Also, the thickness gauge 13 measures the γ-ray radiation I! It has a radiation source and its radiation detector, detects the thickness of the skelp 1, and outputs the thickness signal. And this thickness signal is I10 boat 1
4 to the main control unit 15.

Further, the Skelp temperature distribution detection signal output from the temperature measuring device 6 is sent to the main control section 15 through the I10 boat 14. As shown in FIG. 2, the edge heater 4 is placed on a moving mechanism 4-1 and is moved in the width direction (A) of the scale 1 by the rotation of a motor 4-2.

Now, this main control section 15 has the function of controlling the output of the edge heater 4 and its position, and the heater output section 1
6. The edge temperature comparison section 17 and the edge position control section have various functions for one day. By the way, before explaining each of these functions, a tracking memory 19 is connected to this main control section 15. This tracking memory 19 is formed with one memory area -1 to 19-n for the thickness signal to be taken in.
9-1, and then when the thickness signal is imported, the thickness signal is transferred to the memory area 19-2 and the next thickness signal is stored in the memory area 19-1. Each time the data is entered, the memory area is expanded in sequence.

Then, when the measurement point of the thickness gauge 13 in the Skelp 1 reaches the placement position of the edge heater 4 due to the running of the Skelp 1, the thickness/thickness signal of the measurement point is read out from the thickness signal reading area 19-n of one tracking memory. It has become.

Now, the heater output control unit 16 detects the deviation of the thickness signal level read from the thickness signal readout area 19-n from the thickness signal level of the reference plate thickness, for example, as shown in FIG. ], -10[If it is a V-type, the plate thickness deviation is +10[%].

-10[%], determines a heater output value corresponding to this plate thickness deviation, and sends out a heater output control signal. In other words, the thickness gauge is 13 degrees and the heater output control section is 16 degrees. The edge heater 4 forms a feedforward control system. The edge temperature comparison section 17 is the temperature measuring device 6
It has a function of determining the temperature difference between both edge parts from the edge humidity distribution detection signal from the edge and sending this temperature difference to the edge position control unit 18, which detects this temperature difference within the allowable temperature range. If the temperature is outside the allowable temperature range, the device has a function of determining the edge side with a lower edge temperature and sending a movement control signal to move the edge to that side.

The heater output control signal and movement control signal are I10.
The water is sent to the heater control panel 20 through the boat 14. This heater control panel 20 has an inverter circuit, receives a heater output control signal, controls the voltage applied to the edge heater 4 by the inverter circuit, and sends a movement control signal to the drive motor through the drive section 21.

Next, the operation of the 6A position constructed as described above will be explained. When Skelp 1 runs, Measuring Roll 1
2 outputs a speed detection signal of the number of pulses corresponding to the running speed of the skelp 1, and a thickness gauge 13 measures the thickness of the skelp 1 and outputs the thickness signal. These speed detection signals and thickness signals are sent to the main control section 15 through the I10 port 14, and this main control section 15 receives the speed signals and sends them to the Skelp 1.
The running speed of the tracker is recognized and the thickness signal is stored in a memory area 19-1 of one tracking memory. When the Skelp 1 travels a predetermined distance, the main control unit 15
determines the running speed of the Skelp 1 based on the speed detection signal, and takes in the next thickness signal after the Skelp 1 has traveled a predetermined distance. At this time, the main control unit 15 next transfers the thickness signal stored in the memory area 19-1 to the memory area 19-2 and stores the current thickness data in the memory area 19-1. In this way, the main controller 15 moves the memory area each time thickness data is taken in.

Then, when the Skelp 1 travels and the measurement location of the thickness meter 13 reaches the position where the edge heater 4 is placed, the thickness signal of the measurement location is read out from the memory area 19-n. Here, the heater output control section 16 determines the plate thickness deviation according to the plate thickness deviation characteristic shown in FIG. 3, and sends out a heater output control signal according to this plate thickness deviation. Then, a voltage according to the heater output control signal is applied from the inverter circuit of the heater control panel 20 to the edge heater 4, and the edge heater 4
output is controlled. Here, FIGS. 4 to 6 respectively show the voltage applied to the edge heater 4 with respect to the plate thickness deviation value, and FIG. 4 shows the plate thickness deviation of +6.8%, and FIG. 5 shows the plate thickness deviation of +8. 4%, and FIG. 6 shows the case where the plate thickness deviation is +9.7%. In addition, FIGS. 7 to 9 respectively show the relationship between the edge heater 4 and the plate thickness deviation value when the feedforward control using the thickness gauge 13 in the present application is eliminated.
Figure 7 shows the applied voltage when the plate thickness deviation is +4°1.
%, Fig. 8 shows the case where the plate thickness deviation is +8.9%, and Fig. 9 shows the case where the plate thickness deviation is +H, 5%. Further, the temperature measuring device 6 measures the temperature distribution of the squelp 1 heated by the edge heater 4 and outputs the squelp temperature distribution detection signal. This squelp temperature distribution detection signal is sent to the edge temperature comparison section 17 through the I10 boat 14, and this edge temperature comparison section 17 calculates the temperature difference between both edge parts from the squelp temperature distribution detection signal and sends it to the edge position control section 18. send. This edge position control section 18 does not send out a signal to move the position of the edge heater 4 if the temperature difference is within an allowable range. However,
If the temperature difference between the two edge portions is outside the allowable range, the edge position control unit 18 determines which edge portion has a lower temperature and sends a movement control signal to move the edge heater 4 to this edge portion. This movement control signal is sent to the heater control panel 20 through the I10 boat 14, and further sent to the drive section 21. Thus, the edge heater 4 moves to the side where the edge temperature is low, and the side of the squelp 1 where the edge temperature is low is particularly heated. By the way, similarly, FIGS. 4 to 6 show the temperature of one edge, and FIGS. 7 to 9 show the temperature of one edge using the thickness gauge 13 when feedforward control is eliminated. It is shown. Thus,
The skelp 1 is heated and controlled by the edge heater 4 according to the plate thickness IIA difference and the temperature difference between both edges, and is sent to a forge welding machine 5 to become a forge welded pipe.

By the way, the I! of the forge welded pipe manufactured in this way! The quality of the eye area is expressed in terms of flatness as shown in Figures 10 to 12.
The result will be as shown in the figure. Note that this oblateness indicates the quality of the forgeability of the longitudinal joint portion of the manufactured forge-welded pipe. As shown in the figure, it can be seen that the aspect ratio is improved when feedforward control using the thickness gauge 13 and automatic movement control of the edge heater 4 are adopted.

In this way, in the above-mentioned embodiment, the measurement point of the thickness gauge 13 disposed in the preheating chamber 2 and the front side of the heating furnace 3 is tracked to the edge heater 4 by the heater output control means, and the edge heater is adjusted according to the thickness deviation. 4, and controls the position of the edge heater 4 in the width direction of the squelp 1 by the edge heater position control means according to the temperature difference between both edges measured by the edge temperature measuring device 6 disposed on the downstream side of the edge heater 4. Since the structure is such that the temperature of the squelp 1 can be heated according to the plate thickness deviation, the temperature of both edges can be automatically balanced, and the temperatures of both edges can be controlled equally and with high precision. Therefore, the quality of the forge-welded pipe can be improved, and the yield can also be improved.

Note that the present invention is not limited to the above-mentioned embodiment, and may be modified without departing from the spirit thereof.

〔Effect of the invention〕

As described in detail above, according to the present invention, it is possible to provide an edge heater control device that can control the temperature of the steel strip to an appropriate temperature and balance both edge temperatures with high accuracy.

[Brief explanation of the drawing]

1 to 12 are diagrams for explaining an embodiment of an edge heater control device according to the present invention, in which FIG. 1 is an overall configuration diagram commonly used in a forge-welded pipe manufacturing system, and FIG. FIG. 3 is a diagram showing the action of moving the edge heater. FIG. 3 is a diagram showing the action of determining plate thickness deviation. FIGS. 4 to 6 are diagrams showing inverter output and edge temperature with respect to plate thickness deviation. The figure is a diagram showing inverter output and edge temperature with respect to plate thickness deviation in the conventional technology, Figures 10 to 12 are diagrams showing the aspect ratio, and Figures 13 to 15 are diagrams for explaining the conventional technology. It is. 1... Skelp, 2... Preheating chamber, 3... Heating furnace,
4... Edge heater, 5... Forge welding machine, 6... Temperature measuring device, 10.11... Vinci roll, 12... Measuring roll, 13... Thickness gauge, 15... Main Control unit, 16... Heater output control unit, 17... Edge temperature comparison unit, 18... Edge position control unit, 19...
-Tracking memory, 20...Edge heater control panel. Applicant's agent Patent attorney Takehiko Suzue No. 3 Kokutsuchime Kidney Jibata T Injury Rate (25A) Fig. 10 Fig. 11 Contradiction Wt I Kuhei Prison (80A) Fig. 12 Fig. 13 Fig. 15

Claims (1)

[Claims] In a control device for an edge heater that heats both edges of a steel strip heated in a preheating chamber heating furnace and sends this steel strip to a forge welding machine, the thickness of the steel strip is measured on the upstream side of the preheating furnace. a heater output control means for tracking the plate thickness measured by the thickness gauge to the edge heater and controlling the output of the edge heater according to the plate thickness; an edge temperature measuring device that measures the temperature of both edges of the steel strip; and moving the position of the edge heater in the width direction of the steel strip in accordance with the temperature difference between both edges measured by the edge temperature measuring device. 1. An edge heater control device comprising an edge heater position control means for controlling the edge heater position.