JP2769079B2 - Steel plate temperature measuring device between hot continuous rolling mill stands - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring the temperature of a steel sheet between stands in a continuous hot rolling mill.

[0002]

2. Description of the Related Art In hot continuous rolling, it is important for controlling the quality of a steel sheet to terminate the rolling at a predetermined steel sheet temperature. In the conventional hot continuous finishing rolling mill, the surface temperature of the steel sheet is arranged with a radiation thermometer on the outgoing or incoming side of the rolling mill,
It is measured by the thermometer. (For example, see JP-A-56-1
36227). Based on these measurement results, learning to the next bar of the rolling mill preset or dynamic finishing temperature control (feedback control) in the bar is performed.

However, in hot rolling, there are heat generated during processing of a material (steel plate) and heat removal by a roll, and the temperature of the steel plate at each stand is accurately estimated from the actual temperature at the entrance and exit of the rolling mill. It is difficult to do this, and there are limits to learning presets. Also, in the dynamic finishing temperature control, the feedback control from the exit side thermometer of the rolling mill has a large time delay due to the movement of the steel sheet,
Stable control was difficult.

[0004] From the above, if it is possible to directly measure the steel plate temperature between stands by any means, it is possible to achieve an improvement in the accuracy of learning of presets and an improvement in controllability of dynamic finishing temperature control.

However, between the stands of the hot continuous rolling mill, there is a water wheel such as a roll cooling water on the upper surface of the steel plate, and a large amount of steam is generated. It is difficult to stably measure the upper surface.

On the other hand, although there is no disturbance such as water riding on the lower surface of the steel plate, there is not enough space for a thermometer. For this reason, a device for directly measuring the steel plate temperature between stands has not been proposed yet.

[0007]

As a technology for measuring the temperature from the lower surface of a steel plate, Japanese Utility Model Application Laid-Open No. 61-41409 proposes a temperature measuring device provided with a temperature detector below the steel plate. Since facilities such as a looper and side guides are provided between the stands of the rolling mill, installation space cannot be obtained with such a conventional apparatus, and practical use has been difficult.

In order to reduce the influence of water vapor and the like between the stands, a thermometer must be placed as close as possible to the surface of the steel sheet. In this case, radiant heat from the steel sheet increases, and sufficient cooling is required. In order to do so, there is a contradictory requirement that the device be enlarged.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems, and to have a size that can be arranged even in a narrow space below a steel plate between hot continuous rolling mill stands, and that a lower surface of a steel plate moving between stands is provided. Can be measured close enough to
An object of the present invention is to provide an apparatus for measuring the temperature of a steel sheet between hot rolling mill stands that can obtain a measurement result stably.

[0010]

SUMMARY OF THE INVENTION The present invention is directed to a method for controlling radiation emitted from a steel sheet, which is arranged below a steel sheet moving between a plurality of stands of a hot continuous rolling mill and close to a lower surface of the steel sheet. A lens system for condensing, one end of which is connected to the lens system, an optical fiber for transmitting the radiated light condensed by the lens system, and for converting the radiated light into an electric signal, A temperature detector connected to the other end of the optical fiber, and a water-cooled jacket having an opening for obtaining light emitted from the steel plate, provided to cover one end of the optical fiber and the periphery of the lens system; It is characterized by comprising a heat shield provided on the steel plate side of the water cooling jacket to block radiant heat from the steel plate.

An object of the present invention is to provide an apparatus for measuring the temperature of the lower surface of a steel plate between hot continuous rolling mill stands at a temperature measuring device detecting end (hereinafter referred to as a “detecting end”) such as a lens system, which has an optical fiber connected to the lens system. With this optical fiber, the radiated light from the steel plate condensed by the lens system is transmitted to a temperature detector installed in a good environment outside the rolling mill without attenuating, and the temperature is detected by the temperature detector. This problem can be solved by adopting a configuration in which information is converted into an electric signal, and protecting one end of the lens system and the optical fiber with a water-cooling jacket provided with a heat-insulating plate to protect the steel plate from radiant heat.

Since the lens system and the temperature detector are connected by an optical fiber, it is possible to arrange the temperature detector in a place other than between stands and in a good environment. Therefore, since only the lens system and the optical fiber need to be protected by the water-cooled jacket, the device can be downsized,
It requires less cooling energy. Further, by providing a heat insulating plate in the water cooling jacket, the cooling efficiency for protecting the lens system and the optical fiber is further improved.

[0013] Due to the miniaturization of such an apparatus, the detecting end can be provided in a limited space below the steel plate between the stands and at a position close to the lower surface of the steel plate. Therefore, it is possible to stably measure the temperature of the steel sheet between stands without being substantially affected by water vapor or the like.

Next, the present invention will be described with reference to the drawings. FIG. 4 is a cross-sectional view showing the structure of the detecting end of the temperature measuring device of the present invention, and FIG. 5 is a view taken along line XX of FIG. Lens system 13
One end of the optical fiber 14 is loaded in a water-cooled jacket 15. One end of an optical fiber 14 is connected to the lens system 13. The water-cooling jacket 15 has a heat shield 16 on the steel plate side for blocking radiant heat from the steel plate 9.
Further, the water-cooling jacket 15 has a double structure having a cavity in its tubular body, and cooling water circulates in the body. The cooling water supplied from the water inlet 11a of the cooling water pipe 11 circulates through the body of the water cooling jacket 15 to cool the inside of the water cooling jacket 15 and the heat shield 16 and is discharged from the water outlet 11b.

Reference numeral 12 denotes a purge air pipe. The air from the purge air pipe 12 makes the inside of the water-cooled jacket 15 positive while the pressure inside the water-cooled jacket is higher than the pressure outside the jacket.
The purging (cleaning action by blowing off air) of the tip opening 15b of a is performed.

Reference numeral 10 denotes a water-cooled tube for protecting the optical fiber 14. The water-cooled tube 10 has one end connected to the water-cooling jacket 15 and the other end connected to a temperature detector 17 described later. The water cooling tube 10 has a double structure having a cavity in its body, and cooling water circulates in the body. And water cooling tube 10
Protects the optical fiber 14 from radiant heat from the steel plate, roll cooling water, and the like over its entire length. Optical fiber
14 reaches the temperature detector 17 through the inside of the water-cooled tube 10, and the other end is connected to the temperature detector 17.

FIG. 2 is a front view showing the installation state of the detection end, and FIG. 3 is a side view of FIG. As shown in FIGS. 2 and 3, the detection end 6 is provided between the center guide 8 and the side guide 5. The side guides 5 are arranged on both sides in the moving direction of the steel plate 9 and have a structure that can be opened and closed in the plate width direction. The side guide 5 is preset according to the width of the steel plate. The center guide 8 is arranged below the central part in the width direction of the steel sheet to support the central part of the steel sheet 9 when the steel sheet is passed.

At the detecting end 6 of the measuring apparatus of the present invention, the radiated light from the steel plate 9 passes through the opening 15b at the tip of the upper end 15a of the water cooling jacket 15 and is condensed by the lens system 13. The field of view of the lens system 13 for condensing the emitted light is determined by adjusting the mounting angle of the water cooling jacket 15. That is, as shown in FIGS. 3 and 4, the field of view of the lens system 13 and the upper end of the water-cooling jacket 15
The water-cooling jacket 15 is inclined so that 15a forms an elevation angle of about 45 ° toward the running direction of the steel sheet 9, and the opening 15b at the tip of the upper end 15a of the water-cooling jacket 15 approaches the lower surface of the steel sheet 9. A water cooling jacket 15 is provided. The opening 15b is
In order to prevent intrusion of scale, roll cooling water, and the like, which fall from the steel plate 9, it is formed to have a vertical cut surface.

FIG. 1 is an explanatory view showing an arrangement position of a steel plate temperature measuring device between stands in one embodiment of the present invention. In this embodiment, the detection end 6 of the steel sheet temperature measuring device is disposed between the No. 4 stand 3a and the No. 5 stand 3b in the hot finishing mill 7 shown in FIG.
As shown in FIG. 1, the steel plate 9 is sequentially reduced in thickness in each stand mill 3 and is rolled to a predetermined plate thickness. Numerals 1 and 2 are radiation thermometers arranged on the entrance side and the exit side of the rolling mill, respectively, for measuring the upper surface temperature of the steel sheet. 4 and 5 are a looper and a side guide respectively arranged between the stands.

FIG. 6 is an explanatory diagram showing one embodiment of the system of the measuring apparatus of the present invention. The radiated light from the lower surface of the steel plate 9 is condensed by the lens system 13, transmitted by the optical fiber 14, and converted into an electric signal by the temperature detector 17 installed in a good environment outside the rolling mill. The temperature chart is recorded on the recorder 18. Further, it is input to the control device 19 and used for various controls.

[0021]

The temperature measuring device of the present invention comprises a lens system, an optical fiber, a temperature detector and a water-cooled jacket with a heat shield, and can be installed in a narrow space below the steel plate between stands. Further, since the detection end can be brought sufficiently close to the lower surface of the steel plate, the temperature of the steel plate between stands can be stably measured without being affected by water vapor or the like.

[0022]

Next, the present invention will be described with reference to embodiments. As shown in FIG. 1, the No. 4 stand 3a and the No. 5 stand 3b
The temperature of the lower surface of the steel plate between stands was measured by the apparatus of the present invention. For comparison, the temperature of the upper surface of the steel sheet on the exit side of the rolling mill (finish exit side temperature) was measured by the radiation thermometer 2 on the exit side of the rolling mill. FIG. 7 shows the measurement results. In FIG. 7, the measurement results obtained by the apparatus of the present invention are shown in the lower part, and the measurement results on the exit side of the rolling mill are shown in the upper part. As shown in FIG. 7, both tend to have the same tendency, and it can be seen that the temperature of the steel plate between stands can be stably measured by the apparatus of the present invention.

When there is a temperature difference between the upper surface and the lower surface of the steel plate, the temperature of the upper surface of the steel plate between stands can be estimated by the following method. That is,
The temperature measuring device of the present invention capable of measuring the lower surface of a steel sheet is disposed between stands and on the exit side of a rolling mill. Next, the temperature of the lower surface of the steel sheet between the stands and the exit side of the rolling mill is measured by the apparatus of the present invention, and the temperature of the upper surface of the steel sheet at the exit side of the rolling mill is measured by a conventional radiation thermometer. Then, the temperature of the upper surface of the steel sheet between the stands is estimated from the temperature difference between the upper surface and the lower surface of the steel sheet at the exit side of the rolling mill and the measured value of the temperature of the lower surface of the steel plate between the stands.

[0024]

As described above, according to the present invention, the lens system and the optical fiber are arranged as the temperature detecting end, and furthermore, this is configured to be protected by the water-cooled jacket with the heat insulating plate. The temperature of the steel sheet can be accurately measured without being affected by water vapor or the like by bringing the detection end sufficiently close to the lower surface of the steel sheet, thus providing an industrially useful effect.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an arrangement position of a steel plate temperature measuring device between stands according to an embodiment of the present invention.

FIG. 2 is a front view showing an installation state of a detection end of the temperature measuring device of the present invention.

FIG. 3 is a side view showing an installation state of a detection end of the temperature measuring device of the present invention.

FIG. 4 is a cross-sectional view showing a structure of a detection end of the temperature measuring device of the present invention.

FIG. 5 is a view taken in the direction of arrows XX in FIG. 4;

FIG. 6 is an explanatory view showing one embodiment of the system of the measuring device of the present invention.

FIG. 7 is a graph showing a measured value of the temperature of the lower surface of the steel sheet between stands and a measured value of the temperature of the upper surface of the steel sheet at the exit side of the rolling mill by the apparatus of the present invention.

[Explanation of symbols]

 1, 2 Radiation thermometer 3 Stand mill 3a No. 4 stands. 3b No.5 stand. 4 Looper 5 Side guide 6 Detecting end 7 Hot finishing mill 8 Center guide 9 Steel plate 10 Water cooling tube 11 Cooling water pipe 11a Water inlet 11b Water outlet 12 Purge air pipe 13 Lens system 14 Optical fiber 15 Water cooling jacket 15a Upper end 15b Opening 16 Heat shield 17 Temperature detector 18 Recorder 19 Control device.

──────────────────────────────────────────────────の Continued on front page (72) Inventor Motohiko Kitazawa 32-8 Kumano-cho, Itabashi-ku, Tokyo Chino Co., Ltd. (72) Inventor Ichino 32-8 Kumano-cho, Itabashi-ku, Tokyo Chino-uchi ( 56) References JP-A-58-174821 (JP, A) JP-A-61-41409 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G01J 5/02 G01J 5/08

Claims (1)

(57) [Claims] 1. A lens system for condensing radiated light from the steel sheet, the lens system being arranged below the steel sheet moving between a plurality of stands of a hot continuous rolling mill and in a position close to a lower surface of the steel sheet. An optical fiber, one end of which is connected to the lens system, for transmitting the emitted light condensed by the lens system, and an optical fiber for converting the emitted light into an electric signal, which is connected to the other end of the optical fiber. Temperature detector, a water-cooled jacket provided to cover one end of the optical fiber and the periphery of the lens system, and an opening for obtaining radiation from the steel plate, and a water-cooled jacket on the steel plate side of the water-cooled jacket. An apparatus for measuring the temperature of a steel sheet between hot continuous rolling mill stands, comprising: a heat-insulating plate for shielding radiant heat from the steel sheet provided.