JPS62282247A - Method and apparatus for analyzing components of molten metal - Google Patents

Abstract

PURPOSE:To reduce installation cost to a large extent, by sampling a molten metal specimen by a sampler to feed the same to a laser analyser in a molten state and analyzing the components thereof at a metal melting site. CONSTITUTION:A molten metal specimen is sampled by a sampler 14 having a heat insulating cup 22 and the sampled specimen is fed to the position right under the prober 50 of a laser analyser 4 in a molten state. In this analyser 4, plasma beam is generated from the surface of the specimen by the irradiation of high intensity laser beam and spectrally analyzed to analyze the components of the molten metal. Therefore, the analysis of the components of the molten metal at a metal melting site becomes possible and an exclusive analytical chamber or various analysers for components becomes unnecessary and, therefore, installation cost can be reduced to a large extent.

Description

[Detailed description of the invention] 3. Detailed description of the invention] Industrial applications The present invention relates to a method and apparatus for analyzing components of molten metal.

Lost! Kotogumi's molten metal smelting industry, especially in the steel smelting field, which is its mainstream, has recently seen demands for higher quality and diversified products, as well as for continuous and shorter processes. There is also a need to shorten the time required for component analysis work.

Current mainstream analysis methods include fluorescent X-ray analysis and emission spectrometry, which have themselves met the demand for shortening analysis time.

However, in the case of molten metals, off-line analysis involves transporting the analysis material into the analysis chamber by some method, that is, collecting the sample with a sampler, processing the sample for transportation, shipping it through a pneumatic tube, and processing the sample for analysis. It required the following steps: analysis, communication of results, refinement and adjustment work.

The time required for scouring and ingot making has been shortened.
Perhaps for this reason, by the time the results of the analysis were communicated using this method, the refinement had progressed further. In other cases, the information is only used as reference information for the next process, and in extreme cases, the information is only used as reference information. For this reason, attempts have been made to directly analyze molten metal components using sensors, and this has already been done for carbon, oxygen, and silicon using thermocouples and solid electrolytes, but the precision of carbon and silicon is limited. However, in the case of oxygen, although it is superior in speed because it detects dissolved oxygen, there are still difficulties in how to use it. In response, attempts have been made to directly analyze the components of molten metal using laser light. For example, JP-A No. 57-119241 discloses a device that directly fires a pulsed laser onto molten metal and uses an optical fiber to input the generated plasma light into a spectrometer for spectroscopic analysis. A method of analysis is made by drilling a small hole in the converter wall, emitting three pulsed laser beams while purging inert gas, and guiding the resulting plasma light to a spectrometer.
5 (Examination 32) describes a method of generating a spark discharge between the molten metal and a counter electrode, transmitting the excitation light to a spectrometer using an optical fiber, and directly analyzing the silicon content in the hot metal, as described in P129 (Examination 33).
In the same way as above, the excitation light generated by spark discharge in the molten steel is transmitted to the spectrometer using an optical fiber, and multiple elements are simultaneously analyzed. In addition, P133 (section 34) describes a method for direct analysis of hot metal using an infrared pulsed laser.

Problems that Ming attempts to solve It can be seen from the explanations that each of the above techniques has advantageous features. However, when it comes to practical use, since it is a precision optical device, there are various technical limitations, and depending on the implementation, the device is extremely expensive, so it has not been able to go beyond the realm of laboratory use. This is the current situation. In particular, the current wavelength spectrum of around 200 nm or less cannot be transmitted through optical fibers due to its high attenuation.

In addition, the high temperature and dust at the site were also limiting factors.

Furthermore, as seen in Japanese Patent Application Laid-Open No. 57-119241, it is impractical to expose the tundish or mold of separation equipment to high temperatures of several hundred degrees or more for a long period of time, which requires many protective measures.

It is an object of the present invention to provide a method and apparatus for analyzing components of molten metal that solves these problems.

According to the present invention, a molten metal sample 5 is collected using a sampler equipped with heat-retaining kelp, the collected sample is transported in a molten state to a laser analyzer, and a high-intensity A method for analyzing the components of molten metal is provided, which is characterized by generating plasma light on the surface of a sample by laser light irradiation and performing spectroscopic analysis of the plasma light.

Desirably, the steps of laser light irradiation and plasma light spectroscopic analysis are performed in an inert gas atmosphere.

Furthermore, according to the present invention, there is provided a sampler stocker device that can store a plurality of samplers containing heat-retaining tips and supply them one by one, and a sampler stocker device that can receive the samplers supplied from the sump sheath 1 to the container device and perform a molten metal test 1 case□If+ 4+
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-t CH - RU 17- ÷ A sampling device that transports the sampler to a spectroscopic analyzer and a collection position after analysis, and a plasma light generated by irradiating the molten metal sample in the sampler with high-intensity laser light. A molten metal component analysis device is provided, including a laser spectrometer for performing spectroscopic analysis.

The laser spectrometer has a laser oscillator section, a probe section,
The main body of the analyzer including the spectrometer section and control mechanism, the power supply,
It consists of a controller, data processing and display device, and the spectrometer section includes incident light swans 1 to 1, a concave mirror, a diffraction grating,
Preferably, it includes an image intensifier and a photodiode array.

Since it can be installed on-site, there is no need for a dedicated analysis room, various analysis devices for components, ancillary equipment, sample pneumatic transportation equipment, etc., and equipment costs can be significantly reduced.

If sequence control is performed, the device can complete analysis within 80 seconds, and can be fully used for on-line analysis.

In conventional analysis methods for solid samples, the sample often cannot be used for analysis due to air bubbles and component segregation occurring during the solidification of the collected sample, and it is often necessary to re-sample or collect extra samples due to analysis failure. It was necessary to keep it. In addition, in the case of hot metal, the white pig iron rate was poor. However, according to the present invention, this does not occur and since the collected sample is in a molten state, 100% analysis is possible.

The amount of heat generated by the molten metal in the tip is small, and the main body of the analyzer can be sufficiently thermally protected by the usual heat resistance measures and by blowing out argon gas (inert gas) from the tip of the probe.

For conventional processes that require a lot of labor, such as sample collection - pretreatment for removal and one-shot feeding - pneumatic feeding - pretreatment for analysis TI (cutting, polishing, etc.) - analysis - reporting of results - necessary edge line treatment. sample collection, transportation, analysis, and display of results (in some cases, automatic support for post-processing using a computer)
This simplifies the response and process, requiring less human intervention and allowing analysis results to be obtained with a single touch.

Embodiment FIG. 1 is an overall layout diagram of an analyzer according to the present invention. In the figure, 1 is a molten metal tank (1 dollar), but any molten metal reservoir such as a melting furnace, tundish, mold, etc. may be used in the pond. 1' is molten metal. On the work floor 0, a sampling device 2 having a mechanism capable of rotating left and right is provided opposite to the ladle 1. In relation to the sampling device 2, a sampler stocker 3 and an analyzer main body 4 are appropriately arranged on a movement locus 5 of a tip 22 housed at the tip of the sampling device 2. Also 6
, 7 are a controller and a power supply device for the laser oscillator 55, and a data processing display and control device for the analyzer 4, respectively.

Next, FIG. 2 is a schematic plan view of the sampler stocker 3.
1.11' are gears facing each other at intervals, and 12 is an endless chain. 13 is a holding fitting having an opening 15 in the center and fixed to the chain 12 at equal intervals; 14;
is a sampler. A holding fitting 13 is fixed to a chain 12 stretched along the roadside 11, 11', and a sampler 14 is mounted in an opening 15 of this holding fitting 13. Although not shown, there is a rotary drive device on either side of the gears 11 and 11'.
It is possible to move sequentially by the distance between the attachment fittings 13. As a result, the sampler 14 is intermittently fed in one direction.

FIG. 3 does not show the sampler receiving 3 by the holder [A]. Please refer to FIGS. 1 and 5 for understanding.

The holder 16 is first made of a steel pipe, but there is a hose connection fitting 17 at the upper end, and an air hose 18 is connected from the terminal 19.
extends and is connected to the metal fitting 17. Further, an air chuck section 20 is provided at the lower end, and although not shown, there is a chuck mechanism inside that opens and closes using air force and spring force.

On the other hand, the fixed base 26 is connected to the gear 11 (or 1
1'), and a chain 12 and a holding fitting 13 are attached to the circumferential portion thereof, and the sampler 14 is attached to the holding fitting 13 so that the sampler 14 faces upward outside the handle 213. The extending direction of the handle 21' of the sampler 14' which is intermittently fed and located at the outermost position of the gear 11' is tilted! The center of the holder 16 is aligned with that of the holder 16.

The holder 1 has descended with the air chuck section 20 open.
6 is lowered to a predetermined position at the upper end of the handle 21' of the sampler 14', and the air chuck portion is closed and raised.

As a result, the sampler 14' is pulled out from the stocker 3.

FIG. 4 is a diagram showing the sampler 14. In the figure, the tip 22 is made of a material with good heat resistance and heat retention, such as ceramic fiber material (for example, fine flex mold N with Tombow mark).
o5410) to which an inorganic binder was added, placed in a mold, and compressed and dried. The size is 'l0ax' inside diameter.
As mentioned above, the depth needs to be 5011R or more and the wall thickness needs to be 10u or more, but in the example, the inner bottom diameter is 4011R and the earth scraper is 50U.
'R1, depth 701. It was molded to a thickness of 15zz. A lid 24 made of a material that can withstand combustion, melting, or breakage for at least 2 seconds at the temperature of the molten metal to be immersed, such as thin tin plate, presspod, cardboard, etc., is attached to the molded cap 22 using an appropriate means. Pattern 21
, and the retaining ring 23 which is housed in the handle 21 and supports the tip 22 are made of iron.

Insert the tip 22 from the upper part of the retaining ring 23 of the handle 21.

The outer taper of the tip 22 allows it to fit into a suitable position. In order to fix the tip 22 and the retaining ring 23 and to prevent slag and base metal from adhering to the clamp 21 and the retaining ring 23 in molten metal, a coating 25 with dolomite or the like is applied to the necessary locations. Instead of a coating, a spray of ceramic fibers may be applied.

FIG. 5 is a diagram showing the analysis state of the collected sample.

That is, the sampling device 2 transports the sampler 14 containing the collected sample directly below the probe 50 of the analyzer main body 4, and analyzes the components contained in the sample. In the figure, the sampling device 2 has a rotating ball 30 mounted on a support base 29.
is provided via a receiving portion 31, and a gear 32 is provided at the bottom of the swing ball 30. Nearby there is an electric motor 33 with a reducer, and the small gear 34 at the top is connected to a connecting chain 35.
The gear 32 is rotated via. A support portion 36 is provided on the top of the ball 30, and an arm 37 is supported. The angle of the arm 37 with respect to the ball 30 can be arbitrarily changed 75 by an air cylinder 38.

Further, within the arm 37 there are sprockets 39, 39', with a chain 40 stretched between them. An electric motor 41 with a coaxial reduction gear rotates the chain 40 . The chain 40 moves the holder 1G up and down via the connector 42. 43 is a guide roller for helping the holder 16 move up and down.

17 is an air hose connector, 14 is a sampler, 22 is a tip, and 28 is a stand with a vibration isolator for the analyzer main body 4.

FIG. 6 is a system diagram showing the overall configuration of the analyzer and the analysis state. This analyzer attempts to perform component analysis by irradiating the surface of molten metal with laser pulses, and 6 supplies power and cooling water to the laser oscillator 55, controls the frequency of laser pulses, and controls the gate pulse generator. This is a laser power supply and controller device that performs trigger output to 67.

Data processing, display and control 1A 7 calculates the amount of contained components from a pre-prepared calibration curve based on the relative ratio of the peak value of the target analysis element spectrum and the peak value of the iron spectrum, and displays the value. Transmit. Further, a laser power supply and controller device 6, a diffraction t3 element rotation device 6
4, A/D conversion and controller 68, N2 gas valve 53
, A "Controls the gas valve 54, etc. 67 and 68 are control mechanism sections within the analyzer main body 4.

The analyzer main body 4 consists of a closed metal box 44 into which N2 gas is released controlled by a valve 53, and equipment housed inside. 55
Output cuff 00mJ, pulse width 10nsec, 10Hz
This is a periodic YAG laser oscillator. A laser pulse 70 emitted from a laser oscillator 55 is bent 90° downward by a mirror 56 coated with a dielectric multilayer film, passes through a hole in a perforated mirror 57, and passes through a convex lens 58 made of MgF2 material.
and reaches its focal point, the molten metal surface 45.

Reference numeral 50 denotes a probe fixed to the box body 44, into which Ar gas controlled by a valve 54 can be blown as necessary for sealing. The inside of the tip 22 contains approximately 80 to 90% of the molten metal collected as a sample. Ar gas is blown from the tip nozzle 46 of the probe 5° toward the inside of the tip 22 and the surface of the molten metal. The atmosphere in this entire area is completely replaced with Ar gas. When the molten metal surface 45 is irradiated with a laser pulse 70, plasma 60 is generated at the irradiation point due to its powerful thermal energy.

The plasma light 71 passes through the convex lens 58 and passes through the perforated mirror 5.
7, is bent 90”, passes through a convex lens 61, and passes through a spectrometer 52.
is focused at the entrance slit 69 of the. Plasma light 71 passing through slit 69 is reflected by concave mirror 62 and reaches diffraction grating 63 . Diffraction grating 63 has 2400 lines/JIf
fi is used. The focal length is 11.

The diffraction grating 63 is rotated by a diffraction grating rotation device 64. Note that the diffraction grating rotation device 64 receives an analysis target wavelength signal from the data processing/display/control device, and is thereby rotated to the target wavelength position. Plasma light 71' having the target component wavelength selected by the diffraction grating 63
enters an image intensifier 65 and is intensified, and further converted into an electrical quantity by a photodiode array 66. The AD converter and converter 68 serves to capture and store the optical information supplied to the photodiode array 66, and to perform data processing, display, and control (sending it to the ear device 7). 67 is a gate pulser that serves as a power source and a controller. 6
receives a laser oscillation signal from the laser oscillation signal, applies a high voltage to the image intensifier 65 for a certain period of time, and serves to enhance and contain the plasma light 71' of the target component wavelength, and exchanges information between the photodiode array 66, AD conversion, and controller 68. The function is to control the timing, etc. When performing component analysis with a short wavelength of around 200 nm or less, the entire measurement system including the spectrometer must be kept in a vacuum of 10 -2 Torr or less to prevent light attenuation.

Next, one cycle up to the actual analysis and completion using the apparatus of the present invention will be described.

Set the assembled sampler 14 on the holding fitting 13 of the sampler stocker 3 with the handle 21 facing outward, and 1f[! of the holding fitting 13]. il is upper right 11'
The outermost position of the sampler 14', that is, the kelp 22' of the sampler 14' is set at the 5th position on the travel locus. In the sampling device 2, the reduction gear r= on the arm 37 is rotated by the electric motor 41, and the holder 16 on the connector 42 attached to the chain 4o via the subrogets 39 and 39' is raised to the upper limit position, and The arm 37 has a central extension line of the holder 16 aligned with the sampler 14' in the sampler stocker 3.
Air cylinder 38 up to an angle that matches the center extension of the handle 21'
It is tilted due to the operation of. Next, in the sampling device 2, the small gear 34 is rotated by the drive of the electric reducer-equipped fi 33, and the gear 32 is rotated via the chain 35. Therefore, the ball 30 also rotates at the same time. Holder 16 and sampler 14'
The ball 30 stops rotating when the centers of the handle 21' of the ball 30 are aligned. Next, the holder 16 is lowered by the reverse rotation of the electric motor 41,
The upper end of the handle 21' of the sampler 14' is brought down to a predetermined depth within the chuck portion 20, and then the sampler 14' is lowered and stopped. At the same time, the chuck portion 20 is closed and holds the handle 21'. Holder 16
is raised to the intermediate position, and the sampler 14' is held by the holding bracket 13.
’. The ball 30 is reversed and stopped at the sampling position of 1 dollar 1. The air cylinder 38 provides data 37 up to the angular position at which the sampler 14' is to be immersed.
Tilt. The holder 16 descends to immerse the sampler 14' into the molten metal 1' to a predetermined depth and then stops.

The lid 24' that covers the top of the cup 22' of the sampler 14' which has passed through the slag layer on the surface of the molten metal 1' and stopped at a predetermined position melts (or burns) and contains the molten metal 1' inside.
will flow in. Next, the holder 16 rises, and when the cup 22' reaches a predetermined position on the top surface of the cup 1, the rise is temporarily stopped, and the air cylinder 38 is activated to increase the inclination of the holder 16 (lift it upward). The molten metal inside 22' is discharged together with the impurities floating above it (1
9 holder 16 moves to position 5 of the tip movement locus of sampler 14', and the ball 30 moves so that tip 22' of sampler 14' moves to position 5 of the tip 10 of analyzer main body 4. Turn until you are directly below 50. The probe 50 is configured so that Ar gas is blown out from the nozzle 46 a little before the tip 22' comes directly below.

When the tip 22' comes under the nozzle 46 and is focused, the molten metal surface 45 is irradiated with a pulsed laser. The details of the analyzer are as described above, but it is necessary to irradiate the pulsed laser as many times as the number of target elements to be analyzed.

After the analysis, the sampler is removed from the holder 16 at an appropriate collection position (not shown) and is discarded.
If 9 is to be used for other purposes, it may be collected from the pot 22' after confirming solidification.

The handle 21 and the retaining ring 23 remove deposits, are regenerated, and are reused.One cycle ends when the handle 21 and the holding ring 23 reach 0 or more. In the second cycle, it is sufficient to start by moving the holding fitting 13 of the sampler stocker 3 by one pitch.

I suck ∆ elbow ( According to the present invention, the following effects can be obtained.

Component analysis can be performed at the location of the molten metal, and therefore a dedicated analysis room, various analysis devices and auxiliary devices for components, sample pneumatic transportation equipment, etc. are not required, and the installation cost can be significantly reduced.

If sequence control is performed, the device can complete analysis within 80 seconds, and can be fully used for on-line analysis.

In conventional analysis methods for solid samples, the sample often cannot be used for analysis due to air bubbles and component segregation occurring during the solidification of the collected sample, and it is often necessary to re-sample or collect extra samples due to analysis failure. It was necessary to keep it. In addition, in the case of hot metal, the conversion rate to white metal was poor. However, in this analytical method, this does not occur and 100% analysis is possible because the collected sample is in a molten state.

The amount of heat generated by the molten metal in the tip is small, and the main body of the analyzer is sufficiently thermally protected by normal heat resistance measures and argon gas blowing out from the tip of the probe. I was able to protect it. Conventional methods cannot do this, which is the biggest problem.

Sample collection - Pretreatment for removal and pneumatic feeding - Pretreatment for analysis (cutting, polishing, etc.) - Analysis - Reporting of results -
In contrast to conventional processes that require a lot of manual labor, such as necessary scouring procedures, the process of sample collection, transportation, analysis, and display of results (in some cases, automatic support for post-processing using a computer) has been simplified, and the process has been simplified. Analysis results can be obtained quickly and easily.

The conventional method requires a technician specializing in analysis, but according to the present invention, a field worker who does not require specialized skills is sufficient.

When transporting a sample using a pneumatic tube, the sample pneumatic tube often becomes clogged, which makes analysis impossible and requires repair, but the present invention can solve this problem.

Since the sampler can be partially reused, the cost of consumable parts is significantly lower than with conventional methods.

According to the invention, the sample analyzed is intact and can be used for other purposes.

Online analysis becomes possible, greatly improving productivity and quality.

[Brief explanation of the drawing]

Fig. 1 is a schematic layout diagram showing an embodiment of the analyzer according to the present invention, Fig. 2 is a schematic plan view of the sampler stocker device, Fig. 3 is a schematic side view showing delivery of the sampler, and Fig. 4 is a cross section of the sampler. A side view, FIG. 5 is a diagram showing the analysis form of the collected sample, and FIG. 6 is a system diagram of the laser spectrometer. 1: Molten metal tank (shidol) 2: Sampling device 3, sampler stocker device 4: Analyzer main body 6: Power supply and controller device 7: Data processing, display, control device 14.14': Sampler 22: Heat retention cup 21
．． 21', Handle 52: Spectrometer 55: Laser oscillator 69 Nislit 62: Concave mirror
63: Diffraction grating 65: Image intensifier 66: Photodiode array patent applicant Daihan Sanso Kogyo Co., Ltd.
Figure 1 Figure 5 Figure 4

Claims (5)

[Claims] (1) Collect a molten metal sample with a sampler equipped with a heat-insulating cup, transport the sample in a molten state to a laser analyzer, and generate plasma light on the sample surface by irradiating it with a high-intensity laser beam, A method for analyzing components of molten metal, the method comprising spectroscopically analyzing the plasma light. (2) The analysis method according to claim 1, wherein the steps of laser light irradiation and plasma light spectroscopic analysis are performed in an inert gas atmosphere. (3) A sampler stocker device that can store a plurality of samplers with heat-retaining cups and supply them one by one, and a sampler that receives the sampler supplied from the sampler stocker device, collects a molten metal sample into the sampler, and uses the sampler for laser spectroscopic analysis. It includes a sampling device that transports the sampler to a recovery position after the analysis is completed, and a laser spectrometer that irradiates the molten metal sample in the sampler with high-intensity laser light and spectrally analyzes the generated plasma light. Molten metal component analysis device. (4) The laser spectrometer includes an analyzer main body including a laser oscillator section, a probe section, a spectrometer section, and a control mechanism;
Claim 3, characterized in that the spectrometer section is composed of a power supply, a controller, a data processing and a display device, and includes an incident light slit, a concave mirror, a diffraction grating, an image intensifier, and a photodiode array. The molten metal component analysis device described above. (5) The molten metal component analysis apparatus according to claim 3, characterized in that the sampler includes a heat-retaining cup made of a material with good heat-retaining properties, and a handle made of iron.