JPS58174821A - Device for measuring temperature of lower surface of steel in heating furnace - Google Patents

Abstract

PURPOSE:To measure the temperature of the lower surface of the steel under the stable state, by providing radiation introducing holes in a cooled path so that the radiated light from the lower surface of the steel is introduced into optical fibers provided in the inner tube of double cooling tubes. CONSTITUTION:The cooling tubes 3 are inserted through a measuring hole 2 and positioned at a specified place with respect to the steel 5 in the furnace. The measuring parts of the optical fibers 4 and 4' are positioned at the place where skid marks are located at the lower surface of the steel 5 and the place between the skid marks. The irradiated light from the lower surface of the steel is received through the radiation introducing hole 15 and 15'. The minimum level value and the maximum level value are measured by radiation thermometers 28 and 28', and the measured values are recorded in a display and recording device.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature measuring device for the lower surface of a steel material in a heating furnace.

In the conventional heating furnace, the temperature of the steel material was measured only on the upper surface of the steel material using a radiation thermometer installed in the furnace wall soil.

However, the temperature distribution due to skid marks and the like is rather larger in the lower part, so knowing the temperature in the lower part is important in hot rolling.

However, there is currently no means for measuring this, and in the present invention, we have discovered that good results can be obtained by using optical fibers, and have proposed the present invention.

The structure of the present invention will be explained in detail based on the embodiment shown in the drawings.A cooling tube 3 is inserted through a measurement port 2 drilled in a furnace wall 1 of a heating furnace, and two optical fibers 4,
4' is used to measure the lower surface of the steel material 5.

As shown in FIGS. 1 and 2, the cooling cylinder 3 is composed of an outer cylinder 6 and an inner cylinder 7. The tips of the inner and outer cylinders 7 and 6 are sealed with a tip lid 8, and the inner cylinder 7 is formed long at the rear end. The space between the inner and outer cylinders 7 and 6 is sealed with a rear end cover 9. The tip of the inner cylinder 7 is hermetically sealed with an inner cylinder lid 11 via a sealing material 10. Further, a cooling water outlet 12 is provided at the rear end of the outer cylinder 6, and a cooling water inlet pipe 13 is inserted from the rear end cover 9 to near the tip of the cooling cylinder 3 to form a cooling water channel 14 between the inner and outer cylinders 7°6. Form. In addition, there are synchrotron radiation introduction holes 15°15 at two locations located on the top surface of the inner and outer cylinders 7°6.
' are provided so as to communicate with each other, and both beam introduction holes 15° and 15'
At the location located in the cooling water channel 14, the cylindrical body 16 is connected to the inner and outer cylinders 7,
By fixing between the cooling water channels 6 and 6, a part of the cooling water channel 14 is connected to each other, and the cooling water is configured to be prevented from leaking.

Further, an optical fiber fixture 17 having a semicircular cross section is inserted and fixed into the inner tube 7 as shown in FIGS. 2 and 3. The optical fiber fixing device 17 is provided with a semicircular fixing plate 18 at its tip, a plurality of screw holes 19 and 19 are provided in the fixing plate 18, and the fixing plate 17 is removably fixed to the inner cylinder lid 11 with bolts (not shown). Further, the rear end of the optical fiber fixture 17 has a protruding piece 2o protruding from the outer periphery, and the protruding piece 20 also has a plurality of screw holes 2.
It is removably fixed to a flange 22 provided at the rear end of the inner cylinder 7 with a bolt (not shown) with a 1° angle. In addition, mounting pieces 23 and 23' are fixed horizontally to two locations on the upper surface facing the optical fiber fixture 17, respectively, and a supporting plate 24 has L-shaped optical fibers 4 and 4' fixed thereto.
.

A lens 26 is provided at the tip of each of the optical fibers 4, 4', and the rear end is attached to a protective case 27 (see FIGS. 1 and 4) connected to the flange/22 of the inner tube 7. They are respectively connected to radiation thermometers 28 and 28' installed inside.

The protective case 27 and the rear end of the inner cylinder 7 are provided with support legs 29,
It is supported by a trolley 3o via 29', and the trolley 3° can run on rails 3 and 1 installed outside the furnace.

Note that 320 in FIG. 1 is the N2 gas introduction pipe provided in the inner cylinder 7.

The present embodiment is constructed as described above, and the trolley 30 is moved by the guide of the rails 31, the cooling cylinder 3 is inserted through the measurement port 2, and is positioned at a predetermined location of the preparation 5 in the furnace. Then, both the optical fibers 4 and 4' measurement parts are positioned at the position where the skid mark is located on the lower surface of the steel material 5 and the intermediate position between the skid marks, and the emitted light from the lower surface of the steel material is transmitted to the two radiation light introduction holes 15.
, 15', and measure the minimum value level and maximum value level with radiation thermometers 28 and 28', and record the measured values on a display/recording device (not shown).

On the other hand, cooling water is introduced from the cooling water inlet pipe 13, passes through the cooling water passage 14, and is discharged from the cooling water outlet 12. By circulating the cooling water, the optical fibers 4, 4' are connected to the high temperature of the heating furnace. Avoid being influenced. In addition, N2 gas is introduced into the inner cylinder 7 from the N gas introduction pipe, and the synchrotron radiation introduction hole 1 is
5, the falling objects are discharged from the synchrotron radiation introduction hole 15'.
, 15'.

In the above embodiment, two optical fibers are connected to the radiation thermometers 28 and 28', respectively.
It may be connected to one radiation thermometer and switched sequentially using a switch.

If such a switching means is provided, a large number of optical fibers can be used instead of two, and temperatures at multiple points can be monitored.

It is also possible to measure the temperature distribution on the lower surface of the steel material by using one optical fiber and running the cooling cylinder 3 with the trolley 30.

Furthermore, the synchrotron radiation introduction holes 15 and 15' and the optical fiber 4.
If the cooling tubes 4' are provided not vertically but slightly inclined, it is possible to prevent falling objects from entering and shorten the insertion length of the cooling cylinder 3.

Since the present invention has the above-described configuration and operation, it is possible to prevent falling objects 2.
It is not easily affected by external disturbances such as, and can measure the temperature of the lower surface of the steel material in a stable state.

Moreover, good results can be obtained in measuring the temperature distribution of steel materials.

[Brief explanation of the drawing]

The figures show an embodiment of the temperature measuring device for the lower surface of the steel material in a heating furnace according to the present invention. FIG. 4 is a perspective view showing the fixing means, and FIG. 4 is a sectional view of the protective case. In the figure, 3 is a cooling cylinder, 14 is a passage, and 15 is a synchrotron radiation introduction hole. Patent applicant: Kawasaki Steel Corporation

Claims (1)

[Claims] A device for measuring the temperature of the lower surface of a steel material in a heating furnace, characterized in that a cooling passage is provided in the inner cylinder of a double cooling cylinder provided on the outer periphery.