JPS6259779B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for temperature measurement and/or sampling of molten metal in a metal smelting furnace.

Conventional converter sublance equipment used for temperature measurement and/or sample collection of molten metal inside the furnace is a long device installed above the converter, so the building above the converter is high. In fact, if a large amount of metal or slag adheres to the sublance that has passed through the furnace hood above the converter and is lowered into the furnace, it will not come out of the furnace hood when it is raised, making it necessary to stop the converter operation. , extremely difficult work is required to remove the metal and slag attached to the sub-lance, and the main lance, which is located on the vertical axis of the converter during operation, was avoided and deviated from the axis. Since the sub-lance is inserted into the converter at a fixed position, there are problems such as the sub-lance being deformed due to different heat loads on the furnace center side and the furnace wall side.

In order to solve this problem, an insertion cylinder is connected to the bottom of the converter or to the side wall near the bottom of the converter.
A method has been proposed in which gas for sealing is injected from the insertion tube and a probe is pushed in to measure the temperature of the molten metal and/or take a sample (Japanese Patent Application No. 54-25785). In this method, the sealing gas that is blown into the furnace may flow near the sample inlet of the probe and prevent the molten metal from flowing through the sample inlet. An annular projection projecting radially outward is provided on the outer periphery. Therefore, the inner diameter of the insertion tube into which the probe is inserted must be increased by the amount by which the annular projection protrudes. However, since the annular gap between the inner surface of the insertion cylinder and the probe becomes large, the flow rate of gas for sealing must be increased, resulting in a disadvantage that the amount of gas consumed is large.

The present invention aims to solve the above-mentioned technical problem in a method for measuring the temperature and/or sampling of molten metal from the furnace bottom or a side wall close to the furnace bottom.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall sectional view of an embodiment of the present invention. An insertion tube 2 is provided at the bottom 1a of a metal smelting furnace, such as a converter 1. Probe 3 for temperature measurement and/or sampling of molten metal 9 in converter 1
is inserted into the converter 1 from the insertion tube 2 by the pushing device 4.

FIG. 2 is an enlarged vertical cross-sectional view of the vicinity of the insertion tube 2.
The insertion cylinder 2 communicates with a tuyere 10 formed in the converter 1a, and includes a cylinder 5 extending in a straight line from the tuyere 10 to the outside of the converter 1, an on-off valve 6, and a check valve 7. , and the flexible tube 8 are integrally connected in this order. One end of the cylindrical body 5 is flange-jointed to the hearth bottom 1a. The on-off valve 6 fixed to the other end of the cylindrical body 5 is, for example, a gate valve, and when the valve is open, the cylindrical body 5 and the passage 13 communicate in a straight line, and the probe 3 is connected to the inside of the converter 1. It has a structure that allows insertion and removal into the A gas introduction pipe 11 that protrudes radially outward is connected to the cylinder 5 . This gas introduction pipe 11 is connected to a gas supply source (not shown) through a gas passage 38 formed in the trunnion shaft 28 (see FIG. 1). A gas is constantly jetted from a gas supply source into the cylinder body 5 during operation of the converter 1 to prevent the molten metal 9 from flowing out of the furnace.

The check valve 7 includes a flat valve body 15 whose one end is pivotally supported by a pin 14 perpendicular to the axis of the passage 13.
It is biased by a spring 16 in a direction that blocks the passage 13. A rotation prevention piece 17 is provided on the opposite side of the passage 13 from the pin 14, and when the valve body 15 is in contact with the rotation prevention piece 17 as shown in FIG.
3 is shielded. Probe 3 by pushing device 4
When inserting into the converter 1, the valve body 15 is pushed open by the probe 3. Therefore, the probe 3 can freely pass through the check valve 7.
The check valve 7 configured in this way prevents the molten metal 9 in the converter 1 from flowing from the on-off valve 6 to the pushing device 4 when the on-off valve 6 cannot be completely shut off due to dust or the like. Prevent it from flowing towards the target.

At the lower end of the flexible tube 8, there is a socket 1 consisting of an outer flange 12a and a cylindrical portion 12b extending from the peripheral edge of the outer flange 12a toward the pushing device 4 side along the axis.
2 is fixed.

Such an insertion tube 2 is attached to the bottom 1a of the converter 1, forming an angle α with the vertical line. This angle α
is selected such that 30°≦α≦150°. In addition, insertion tube 2
may be attached to the side wall of the converter 1 near the bottom 1a. When the angle α is in the range of more than 150 degrees and less than 180 degrees, a large amount of sealing gas is required, and it becomes difficult to separate the probe from the sealing gas. An angle α of less than 30 degrees is not possible due to the configuration of the actual device.

FIG. 3 is an enlarged longitudinal sectional view of the probe 3,
Shown for reference. The sample collection container 19 with the sample collection chamber 20 is integrally surrounded by a protective tube 18 made of multiple laminated paper. A sample inflow hole 21 communicating with the sample collection chamber 20 is connected to the side wall 18a near the tip of the protection tube 18 and the side wall 1 of the sample collection container 19.
It is formed to penetrate through 9a. A molten metal temperature measuring element 25 in which a thermocouple 24 is embedded is fixed to the tip 18c of the protection tube 18, and a freezing point temperature measuring element 27 in which a thermocouple 26 is embedded is fixed to the rear part 19b. Each thermocouple 2
Lead wires 4 and 26 are connected to the rear end 18b of the protective tube 18.
pulled outward from the The tip of the piston rod 22 of the pushing cylinder 29 is inserted into the rear end of the probe 3 .

FIG. 4 is a sectional view taken along the section line - in FIG. 1. Referring to FIGS. 1 and 2, the pushing device 4 includes a pushing cylinder 29 for pushing the probe 3 into the converter 1. As shown in FIG. One end of this pushing cylinder 29 on the converter 1 side has a pushing cylinder 2
A guide tube 30 having the same axis as 9 is connected.
An outer flange 31 that is removably fitted into the socket 12 of the flexible tube 8 is fixed to the end of the guide tube 30. A support ring 32 is integrally provided in the middle of the pushing cylinder 29, and a pivot 33 is fixed to the support ring 32 along one diameter line. This axis 3
3 is a bracket 35 erected on a support stand 34;
36. A gear 37 is fixed to one end of the pivot 33. A motor 39 with a speed reducer is fixed to the support base 34, and a gear 4 meshing with the gear 37 is attached to the output shaft of the motor 39.
0 is fixed. Therefore, by driving the motor 39, the pushing cylinder 29 and the guide tube 30 are rotated around the pivot shaft 33, so that the pushing cylinder 29 and the guide tube 30 are tilted at an arbitrary angle, and the flexible tube is rotated. 8 can be reliably connected.

A substrate 42 is fixed to a side wall 41 of a pit or the like below the converter 1. A support body 44 is provided on this substrate 42 . This support body 44 has cylinders 45, 46, 47 arranged at equal intervals in the circumferential direction.
is provided. Each cylinder 45-47 has pin 4
8, 49, and 50 to the lower surface of the support base 34. The cylinders 45 to 47 are arranged at equal intervals in the circumferential direction of the pushing cylinder 29. Therefore, by driving the cylinders 45 to 47 to expand and contract, the axial positions of the support base 34 and the pushing cylinder 29 can be determined.

In the pushing device 4, the length of the piston rod 22 is such that when the pushing cylinder 29 is driven to extend,
As shown in FIG.
The length is chosen such that it lies inward by l2. The distances l1 and l2 are five times or more the outer diameter d of the probe 3. If the outer diameter d is less than 5 times, a representative temperature cannot be measured.

When measuring the temperature of the molten metal 9 in the converter 1 and/or collecting a sample, the cylinders 45 to 47 and the motor 39 are driven to fit and connect the outer flange 31 of the guide tube 30 to the socket 12. Note that the flexible tube 8 allows the axes of the guide tube 30 and the check valve 7 to be slightly deviated. After connecting the guide tube 30 to the insertion tube 2, the on-off valve 6 is opened. Then, the pushing cylinder 29 is driven to extend, and the probe 3 is attached to the tip of the piston rod 22 as shown by the imaginary line in FIG.
is pushed into the molten metal 9 in the converter 1 through the insertion tube 2.

During this pushing operation of the probe 3, the insertion tube 2
A sealing gas is injected into the interior from a gas introduction pipe 11, and the sealing gas flows through an annular gap between the probe 3, the piston rod 22, and the cylinder 5, as shown in FIG. It spews out into the furnace 1. Therefore, the molten metal 9 in the converter 1 is inserted into the insertion tube 2.
This prevents leakage into the interior. The injected sealing gas becomes a bubble flow and rises in the converter 1 as shown by an arrow 23.

The probe 3 is inserted deeper into the converter 1 than the rising bubble flow 23, and the molten metal temperature measuring element 2
5 and the sample inflow hole 21 are located above. Therefore, the rising bubble flow 23 of the seal gas does not flow past the molten metal temperature measuring element 25 and the vicinity of the sample inflow hole 21, and the molten metal 9 in the converter 1 flows from the sample inflow hole 21 into the sample collection chamber 20. The temperature of a typical molten metal 9 that easily flows into the molten metal 9 and is not heated or cooled by the seal gas is measured.

After measuring the temperature and/or collecting a sample using the probe 3, the pushing cylinder 29 is driven to contract and the probe 3 is returned into the guide tube 30. Then,
The operation is completed by closing the on-off valve 6 and disconnecting the guide tube 30 and the insertion tube 2.

The present invention can be widely implemented in connection with not only the converter of the above-mentioned embodiments but also metal smelting furnaces and ladles such as degassing furnaces, electric furnaces, and pig iron mixing furnaces.

As described above, according to the present invention, the probe is inserted into the metal smelting furnace so that the molten metal temperature measuring element and the sample inflow hole are located away from the rising bubble flow of the sealing gas, so that the outer periphery of the probe Even without the annular protrusion, the molten metal temperature sensing element is not affected by the seal gas, and the molten metal is not prevented from flowing into the sample inflow hole. Therefore, it is possible to reduce the diameter of the insertion tube, and the consumption of sealing gas can be reduced accordingly.

Further, according to the present invention, the positions of the probe molten metal temperature sensing element and the sample inflow hole are selected so as to be separated from the upward bubble flow of the sealing gas along the axis of the probe by at least five times the outer diameter of the probe,
Therefore, it is possible to reliably measure representative temperatures.

Moreover, according to the present invention, the axis of the insertion tube is
Since it is formed at an angle of 30 degrees or more and 150 degrees or less with the vertical line, an unnecessarily large amount of seal gas is not required, and the probe can be separated from the seal gas. .

[Brief explanation of the drawing]

Fig. 1 is an overall sectional view of one embodiment of the present invention;
3 is a sectional view of the probe 3, and FIG. 4 is a sectional view taken along the cutting plane line - in FIG. 1. 1... Converter, 1a... Hearth bottom, 2... Insertion tube, 3
... Probe, 4 ... Pushing device, 9 ... Molten metal, 21 ... Sample inflow hole, 23 ... Rising bubble flow,
d...Probe outer diameter, α...Inclination angle of insertion tube.

Claims (1)

[Claims] 1. Measure the temperature of the molten metal by injecting seal gas from the insertion tube provided at the bottom of the metal smelting furnace or on the side wall near the bottom of the furnace, and inserting a probe equipped with a molten metal thermometer and/or sample inlet hole. and/
Alternatively, in the method for sampling a sample, the probe is inserted into a metal smelting furnace such that the molten metal thermometer and the sample inflow hole are located away from the upward bubble flow of seal gas in the metal smelting furnace, and the probe is The positions of the molten metal thermometer and the sample inflow hole are selected so that they are separated from the upward bubble flow of the sealing gas by at least five times the outside diameter of the probe along the axis of the probe, and the axis of the insertion tube is aligned with the vertical line. A method for temperature measurement and/or sample collection of molten metal, characterized in that the temperature is tilted at an angle of 30 degrees or more and 150 degrees or less.