JPS5838841A - Analysis of iron, steel or the like - Google Patents

Abstract

PURPOSE:To achieve a shorter time and automation by causing a discharge between the surface of a molten steel and an electrode rod provided at the tip of analysis tube body with an optical fiber to excite an emission which is transmitted to an analysis chamber to analyze. CONSTITUTION:An electrode rod 3 for emission made of silver, tungsten or the like is screwed into the center of the tip face of an analysis tube 2. A jig 7 is securely inserted into the outer surface on the tip side of the analysis tube 2 and an optical fiber 8 and a small electrode rod 9 for sensing the surface of a molten steel are buried into the surface of the tube. The tip of the optical fiber 8 is exposed to the inner wall surface of the jig 7 facing the tip side of the emission electrode bar 3 while the rear end is connected to an optical fiber 12. When the tip of the small electrode rod 9 reaches the surface 18a of the molten steel, an emission is caused with a discharge between the emission electrode rod 3 and the surface 18a of the molten steel and transmitted to an analysis chamber to analyze, thereby enabling automation with a shortened analysis time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention, in a refining and casting machine s41 of pig iron or steel, generates a discharge between the surface of molten iron or molten steel and an electrode rod to excite luminescence, which is then dispersed into spectroscopy using an optical fiber. This relates to an analysis method that transmits data to an analyzer and automatically analyzes iron or molten steel.

In general, in pig iron or steel refining and casting operations 11, etc., controls based on molten iron or molten steel composition information are used to improve refining accuracy, increase yield, and shorten the total steelmaking time. K is trying to do the same. Conventional methods for obtaining ms iron or molten steel composition information, even in d converter blowing, include the force-pond meminator method and the sampling/analysis method. Carbon Determination! The method involves sampling molten steel in a small container, measuring the solidification temperature of the molten steel using a thermocouple, and estimating the carbon content from a comparison table of carbon content and solidification temperature prepared in advance. However, in this case, only carbon is obtained as the KFi element, and there are disadvantages in that the temperature measurement error of the thermocouple affects the carbon measurement error, and it takes about 10 seconds to complete solidification after Ku sampling. was there. Incidentally, the longer the time from sampling to the completion of solidification, the more the molten steel temperature will decrease and the 1 wA rate will decrease.

On the other hand, in the sampling/analysis method, molten steel is sampled with a probe (usually a small container housed in a heat-resistant paper tube) attached to the end of a sublance, and the sample is sent to an analysis room using an air chute etc. A sample (molten steel sample) that has already become a solidified solid is cut in the analysis room, the cut surface is polished, and the light emitted when the polished surface is irradiated with high energy is analyzed using a spectrometer. In this case, although Ktlj has the advantage of being able to analyze most of the elements with high accuracy, it has the disadvantage that it takes several minutes from sampling to completion of analysis, and it also requires the time and effort of cutting and polishing as preliminary processing. The workers who were engaged in the work were being scavenged. Moreover, the above-mentioned work requires equipment such as a cutting machine and polishing machine, as well as equipment such as an air chute for transporting the sample to the analysis room, resulting in the disadvantage that the overall equipment becomes larger.

The present invention improves and eliminates the above drawbacks of the conventional art by providing an electrode rod and an optical fiber at the tip of one analysis tube body, and emitting light by causing a discharge between the electrode rod and the surface of molten steel, for example, and L. was excited and transmitted to the analysis room using the above optical fiber for analysis, and the analysis Kll! By shortening the Ichinoseki process and automating the analysis, Refiner 1! The aim is to provide a method for analyzing iron, steel, etc. that can realize fully automated processing and rapid processing.

The method of the present invention will be explained below based on the embodiments shown in the figures.

FIG. 1 is a system diagram showing the entire case when the method of the present invention is applied to converter blowing work. In the figure, the lfl converter, 2, is a sub-lance serving as an analysis tube. # On the tip end surface (lower end surface in the drawing) of the sub-lance 2, a central aK lamp, as shown in FIG. 2, is screwed together with a light-emitting electrode rod 3 made of tungsten or tungsten*x9. The tip of the electrode rod 3 has a conical shape and projects downward from the tip l1lIilWA of the sublance 2. A plurality of gas injection ports 4 are opened around the electrode rod 3 on the tip 1111I surface of the Makina Plane 2 . The injection port 4 communicates with a water supply source (not shown) K via a hose 6 that is continuous with the water communication path S.

Reference numeral 7 denotes a jig which is fitted and fixed to the outer m surface of the tip side of the sub-lance 2, and can be replaced at will.

Jig 7r1. For example, it is a tube made by wrapping heat-resistant paper to a predetermined thickness, and inside the tube wall there are installed fibers 8 and small electrode rods 9 for sensing the surface of molten steel. The tip of the optical fiber 8 is exposed to the inner wall surface of the jig 7 so as to face the tip side of the light emitting electrode rod 3, and the tip of the optical fiber 8 is exposed to the inner wall surface Kll of the jig 7, and the tip of the optical fiber 8 is 1llll!
The optical fiber 12 is connected to a spectroscopic analyzer 11 in the analysis room via a connector 1G. Small electrode rod 1f
Ill? The tip of the A-shaped electrode 11 protrudes downward, and the light-emitting electrode rod 31 is also set downward by a predetermined length. Den II
It is marked *II in the circuit 13. 14ri, a circuit that controls the motor for raising and lowering Naplans, displays 1t, 16t that display data from the IS spectrometer 11! The above spectroscopic analyzer 1
This is a combi-aime that performs process control of the entire converter blowing work based on the data obtained in step 1.

Next, the present invention will be described in detail based on the embodiments described above with reference to FIGS. 1 to 4.

When the main lance (not shown) completes the prescribed pure oxygen injection work in the converter l, a signal is sent to the converter 16H that performs process control and the circuit 14 that controls the motor for lifting and lowering the naponce, and the sub-lance Lower 2. In the sub-lance 2, the gas from the gas supply source (in this case, argon gas is used) is injected from the injection port 4 formed on the tip surface, so that the % sub-lance 2 becomes the slag 17. As K approaches , the injected gas begins to blow away the slag 17, as shown in FIG. Then, the slug 17ec is drilled to create a space large enough so that the tip of the jig 7 does not interfere with the slug 17.

18 m of the surface of the molten steel 18 is exposed. The descent of the sub-lance 2 further progresses, and the tip of the small electrode rod 9 touches the molten steel 1!1ia1
When 8aK is reached, the small electrode rod 9 is electrically short-circuited, forming a circuit that flows from the small electrode rod 9 through the molten steel 18 and the earth rod 19 of the converter I to the ground. The power supply circuit 11c senses the short circuit and outputs No. 9 to the control circuit 14 of the sub-lance lifting motor, thereby switching the lowering operation of the sub-lance 2 to the upward operation.

A high voltage is applied to the light-emitting electrode rod 3 at the same time as W&.

Here, the tip of the light-emitting electrode rod 3 and the molten steel surface 18a
A spark discharge occurs between the molten steel 18 and the molten steel 18 to emit light. The emitted light at that time is received by the optical fiber 8 and sent to the spectroscopic analyzer 1 in the analysis room via the optical fiber 12.
Transmit to 1. The spectroscopic analyzer 11 analyzes the above emission spectrum 1, the amount of the element III, and the amount K1! [41 is detected, and this is displayed on the display 15, and is sent to the computer 16 that manages the entire process of blowing work, and is compared with a preset l target value to reach the am value KIM. If it is, the blowing work is considered complete, and if it is less than the target value, the remaining blowing work is instructed to reach the target value.

Note that light with a wavelength smaller than 2000 A usually has the property that it is absorbed when there is oxygen in the atmosphere, but in the case of the present invention, Kti, even during the above spark discharge, the gas body (in the case of nickel) Since argon gas) is continuously injected, the tip of sublance 2 and the surface of the molten steel are 11 m long.
This replaces the atmosphere of the leap with air, air, and fills it with argon gas, so the wavelength λ or zoom!
P% (e.g., O, P, 841FO) elements can be transmitted to the optical fiber 8 via argon gas without attenuation. 1;, C, 81 to this
, Mu, P.

Each element of B11 can be easily analyzed.

According to experiments, it took only 15 seconds from the start of the descent of Sublance 2 to the obtaining of the analytical results.This clearly shows how superior the method of the present invention is.

By the way, although the above example is a case of converter blowing, the method of the present invention is not limited to the above specific equipment (
It goes without saying that this lamp can also be applied to the analysis of molten steel or molten iron in ladle refining, foundry @Q, etc.

As explained above, in the present invention, an electrode rod and an optical fiber are connected to the tip of an analysis tube, a discharge is caused between the electrode rod and the surface of molten iron or molten steel, etc., to excite light emission, and the light emission is excited as described above. The KL7t transmits data via optical fiber to the spectrometer in the analysis room for analysis, allowing instant analysis.
1.11" The time required to prepare the Kt sample is significantly shortened, and there is no need for the traditional work of cutting, cleaning, and polishing the Kt sample, and the work can be fully automated. Furthermore, the work can be fully automated. There is no need for large-scale equipment such as an air shade for conveying the material to the container, which is advantageous in terms of cost.

[Brief explanation of the drawing]

Figure 1 is an overall system diagram showing the case where the method of the present invention is applied to converter blowing. @ is an enlarged longitudinal sectional view of the main part of the tip of the t-prance, and Figure 113 is the l! In the longitudinal cross-sectional view of the section, the fourth cause is the tip of the naplanth, which shows the excited emitted light! ! FIG. 2... Analysis tube (sublance) 3-... Electrode rod 8.12... Optical fiber 18m... Molten steel III
Patent applicant Sumitomo Metal Industries Co., Ltd. Attorney Toshihiko Enda

Claims (1)

[Claims] 1. Install an electrode rod and an optical fiber at the tip of the analysis tube, connect the wrinkled optical fiber to a spectroscopic analyzer, and generate a discharge between the electrode rod and the surface of molten iron or steel. A method for analyzing molten iron and molten metal by transmitting it through an optical fiber to the above-mentioned spectroscopic analyzer, which is characterized by the following features: