JPH01284718A - Method and device for detecting in-furnace temperature - Google Patents

Abstract

PURPOSE:To prevent tungsten from being eroded by a reducing gas by loosely fitting an inside cylinder made of refractories internally provided with tungsten- rhenium thermocouples onto an outside cylinder made of refractories and detecting an in-furnace temp. while supplying an inert gas to the spacing therebetween. CONSTITUTION:The inside cylinder 4 which consists of an alumina material and in which the two W, Re thermocouples 2, 2a shifted at the temp. detection point to the right and left are supported in parallel in a loose fitting state by means of supports 3 supported on the inside peripheral face of said cylinder and gaseous Ar is sealed is loosely fitted into the outside cylinder which consists of an alumina material and is opened at both ends. The supply pipe of a gaseous nitrogen supplying device which supplies the gaseous nitrogen to the spacing 5 between the two cylinders 1 and 4 is connected to the leading out side of the detected temp. The inside of the space 5 is filled with the gaseous nitrogen when the gaseous nitrogen is supplied into the space 5 and the infiltration of the reducing atmospheric gas to the inside of the inside cylinder 4 in which two pairs of the W, Re thermocouples 2, 2a are inserted is obviated and, therefore, the deterioration of the W is decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a method for detecting furnace temperature and a method for detecting the temperature in a furnace, which can be used in a stable state at high temperatures in a reducing atmosphere containing carbon oxide. Concerning vessels.

(Prior Art) As is well known, the tungsten-rhenium thermocouple (hereinafter abbreviated as W-Re thermocouple) has been used as a thermocouple for measuring high temperatures of 1400 to 3000'C due to its melting point. ) is used.

However, due to the nature of the material, it is limited to use in a vacuum, hydrogen atmosphere, or inert gas atmosphere. - Tungsten (hereinafter abbreviated as W) deteriorates significantly in a reducing atmosphere containing carbon oxide. It was unsuitable for use as a

On the other hand, as is well known, ceramics are sintered in a high-temperature reducing atmosphere, and the temperature inside the furnace can be measured over a long period of time.
Records are essential for manufacturing ceramics etc. of excellent quality.

Therefore, a temperature sensor for reducing atmospheres equipped with a W-Re thermocouple was developed that made it possible to measure high temperature in reducing atmospheres by insulating this thermocouple from reducing atmospheres. ing.

The conventional example of a temperature detector for reducing atmosphere as mentioned above is
This will be explained below with reference to FIG. 4, which is a side sectional view of the main part near the temperature detection section.

This temperature sensor has two pairs of W-Re thermocouples (52) arranged in the longitudinal direction inside an outer cylinder (51) made of alumina material and filled with argon gas (hereinafter abbreviated as Ar). It is supported by a support (53) supported in parallel and on its inner circumferential surface, and an inner cylinder (54) made of alumina material and having A' sealed therein is installed in a loosely fitted state. It is the composition.

[1. ::(DW-Rev!,'rJ1 pair (52)
C. The Ar sealed in the inner cylinder (54) and the outer cylinder (51) isolates it from the reducing atmosphere, reducing the deterioration of W, making it possible to stably detect the temperature.

(Question B to be solved by the invention) The temperature detector for reducing atmosphere equipped with the above-mentioned W-Re thermocouple is useful as it can detect high temperatures of 1400°C or higher, but it cannot be used for a long period of time. From the viewpoint of stability, there are still problems as explained below.

That is, - the temperature of the reducing atmosphere containing carbon oxide is 1400
As is well known, when the temperature exceeds °C, the gas sealing function of the cylinder made of alumina material deteriorates, and the Ar sealed inside the cylinder leaks out of the cylinder.
Carbon monoxide, which is given energy by high temperatures and moves violently, enters the inside of this cylinder and deteriorates the W, so it is impossible to use a temperature sensor configured like this in a stable state for a long period of time. The problem was that it was possible.

The inventors have attempted to solve the above-mentioned problems and have developed a W for reducing atmosphere that can be used in a stable state for a longer period of time.
-He worked hard to develop a temperature detector equipped with a Re thermocouple.

(Means for Solving the Problems) The method for detecting the temperature inside a furnace according to the present invention focuses on the fact that the gas sealing function of a refractory cylinder deteriorates, and therefore, the method according to the first invention The gist of the method for detecting the temperature inside the furnace is to loosely fit a refractory inner cylinder with a tungsten-rhenium thermocouple inside into a refractory outer cylinder, and to fill the space between the inner cylinder and the outer cylinder. It is characterized by detecting the temperature inside the furnace while supplying active gas.

Further, the configuration of the furnace temperature detector according to the second invention includes a bottomed inner cylinder in which a tungsten-rhenium thermocouple is installed and an inert gas is sealed; It is characterized by comprising an outer cylinder having a gas discharge part on the side thereof, and a supply device for supplying inert gas to the space between the outer cylinder and the inner cylinder on the outlet side of the thermocouple.

Further, the configuration of the furnace temperature detector according to the third invention includes a bottomed outer cylinder into which the inner cylinder is loosely fitted, and a space provided along the longitudinal direction of the space between the inner cylinder and the outer cylinder. , and a partition plate having a gas circulation part on the bottom side of the outer cylinder, a supply device for supplying inert gas to one side partitioned by a chain plate on the side opposite to the bottom side, and a discharge port for discharging inert gas to the other side. It is characterized by having the following.

(Function) In the present invention, the temperature detection method for a reducing atmosphere and the configuration of the detector are as described above, so that the gas supplied from the inert gas supply device is distributed between the inner periphery of the outer cylinder and the inner cylinder. The gas that passes through the space between the outer peripheries and flows out from the outer cylinder on the opposite side to the detected temperature derivation side, or the gas that is supplied from one side separated by a partition plate, flows out from the other outlet, so the gas inside this space Because the tube is filled with inert gas during temperature detection, reducing gas does not enter into the inner tube into which the W-Re thermocouple is inserted.

(Example) An example of a furnace temperature detector equipped with a W-Re thermocouple according to the present invention will be described below with reference to FIGS. 1 to 3.

This first embodiment will be explained based on FIG. 1, which is a side sectional view of the main part near the temperature detection section.

That is, in the figure, two W.Re thermocouples (2), (2a) with temperature detection contacts shifted left and right are supported by a support (3) supported on their inner peripheral surfaces in a loosely fitted state in parallel,
The inner cylinder (4) is made of alumina material and is filled with Ar.
) and an outer cylinder (1) made of alumina material with open ends.
), and although not shown, there is a nitrogen gas supply device that supplies nitrogen gas to the space (5) between the cylinders (1) and (4) on the detection temperature output side. The structure consists of connecting pipes.

Therefore, nitrogen gas is supplied to the space (5) from the nitrogen gas supply device.
), this space (5) is filled with nitrogen gas, and the nitrogen gas is reduced to the η portion of the inner cylinder (4) through which the two pairs of W-Re thermocouples (2) and (2a) are inserted. Since there is no intrusion of harmful atmospheric gases, deterioration of W due to reducing atmospheric gases is reduced.

Incidentally, in an example in which the temperature of a reducing atmosphere containing -carbon oxide was measured around 1600'C, continuous use was possible in a stable state for two months.

Although it is not used to detect temperatures in the high temperature range exceeding 1600°C and up to about 3000"C, it can be used for a longer period of time than conventional temperature detectors for reducing atmospheres even in such high temperature ranges. It is thought that it is possible.

Solution 2 First, this embodiment will be described based on FIG. 2, which is a side sectional view of a main part near the temperature detection section, and FIG. 3, which is a sectional view taken along the line 2--2 of FIG. Note that the same parts as in the first embodiment are indicated by the same reference numerals.

That is, the reference numeral (1) shown in the figure is a support (2), (2a) supported by the inner circumferential surface of two W-Re thermocouples (2), (2a) whose temperature detection contacts are shifted from side to side in a loosely fitted state in parallel. The inner cylinder (4) made of alumina material is supported by the W-Re thermocouple (2), (
An outer cylinder (1) made of alumina material with an open outlet side
) was loosely fitted inside. Then, the inner cylinder (4) and the outer cylinder (1
), the radial cross section of the space (5) is divided into three equal parts, and the space (5) between the inner cylinder (4) and the outer cylinder (1) is divided into three equal parts.
), and a supply pipe of a nitrogen gas supply device for supplying nitrogen gas is connected to one side partitioned by the partition plate (6) on the outlet side; Moreover, the other side was configured to serve as an outlet for the supplied nitrogen gas.

Therefore, in a detector configured like this, when nitrogen gas is supplied from one side by the supply device, the nitrogen gas flows while covering the outer periphery of the inner cylinder, passes through the bottom side of the outer cylinder, and flows out from the outlet. Therefore, its operation and effect are the same as those of the first embodiment.

In all of the above embodiments, since nitrogen gas is supplied to the space (5) between the inner cylinder (4) and the outer cylinder (1), the detected temperature is detected as being lower than the actual temperature. It is possible that

Regarding this point, no problem will arise in use if the detected value is calibrated by a verification comparison test.

Incidentally, in the example where nitrogen gas was supplied at me/min, the degree of the detected temperature drop was about 0.5°C at most.

In addition, in conventional temperature detectors for reducing atmospheres,
Since the temperature detection contacts of W/Re thermocouples are located at the same position in the longitudinal direction of the cylinder, there is a problem that during use, the temperature detection contacts may come into contact with each other and the detected value may become abnormal. However, in the present invention, as described above, the positions of the temperature detection contacts are shifted in the longitudinal direction of the cylinder, so the problem of the temperature detection contacts coming into contact with each other is eliminated.

In this example, Ar was sealed inside the inner cylinder (4), but other inert gases other than Ar could also be filled, and nitrogen gas could also be supplied to the space (5). However, it is also possible to supply other inert gases than nitrogen gas, and the use of nitrogen gas is merely an economical consideration.

In addition, in this example, both the inner and outer cylinders are made of alumina material, but other materials other than alumina material may be used, such as cylinders made of oxides such as beryllium oxide, cerium oxide, magnesium oxide, and thorium oxide. can do.

Further, in this embodiment, a temperature sensor equipped with two pairs of W-Re thermocouples has been described, but the thermocouples may be a pair, or may be made of other materials that are easily corroded by a reducing atmosphere. It can also be applied to thermocouples.

(Effects of the Invention) In the present invention, a temperature sensor for a reducing atmosphere is fitted into a W-shaped tube loosely fitted into a bottomed inner cylinder made of a refractory filled with an inert gas.
A Refi couple, an outer tube into which this inner tube is loosely fitted, and one end of which is made of a refractory material through which gas can flow; The configuration includes a supply device that supplies inert gas to the space.

Therefore, the gas supplied from the inert gas supply device flows through the space between the inner circumference of the outer cylinder and the outer circumference of the inner cylinder.

Therefore, since this space is filled with nitrogen gas during temperature detection, reducing gas does not penetrate into the inner cylinder where the W-Re thermocouple is inserted, so W is reducing. No more erosion caused by gas,
It has become possible to use it stably for a long period of time.

In addition, since it can be used stably for a long period of time, it not only makes it possible to reduce the cost of the temperature measuring device itself and its replacement work, but also has the economical benefit of improving the operating rate of ceramic processing furnaces, etc. It has also had an effect.

Therefore, according to the present invention, it has been possible to realize an extremely excellent and useful furnace temperature detection method and its detector equipped with a W-Re thermocouple for a reducing atmosphere that can be stably used for a longer period of time.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of the main part near the temperature detection part of the temperature detector according to the first embodiment, and FIG. 2 is a side sectional view of the main part near the temperature detection part of the temperature sensor according to the second embodiment. FIG. 3 is a sectional view taken along the line In-11I in FIG. 2, and FIG. 4 is a side sectional view of a main part near the temperature detection section of a conventional temperature sensor. (1) - outer cylinder, (2), (2a) - tungsten rhenium thermocouple, (3) - support, (4) - inner cylinder, (5) - space. Patent Applicant Kobe Steel Corporation Representative Patent Attorney Akira Kanemaru −

Claims (3)

[Claims] (1) A refractory inner cylinder with a tungsten-rhenium thermocouple inside is loosely fitted into a refractory outer cylinder, and the furnace is heated while supplying inert gas to the space between the inner cylinder and the outer cylinder. A method for detecting temperature inside a furnace, characterized by detecting temperature inside a furnace. (2) a bottomed inner cylinder in which a tungsten-rhenium thermocouple is installed and an inert gas is sealed; an outer cylinder into which the inner cylinder is loosely fitted and has a gas discharge part on one end; What is claimed is: 1. A furnace temperature detector, comprising: a supply device for supplying an inert gas into a space between an outer cylinder and an inner cylinder, on the outlet side of the pair. (3) A bottomed outer cylinder into which the inner cylinder is loosely fitted, and a partition provided along the longitudinal direction of the space between the inner cylinder and the outer cylinder and having a gas flow part on the bottom side of the outer cylinder. a supply device that supplies an inert gas to a plate and one side partitioned by the plate on the side opposite to the bottom;
A furnace temperature detector characterized in that the other end is provided with an outlet for discharging inert gas.