TWI493163B - Mounting structure of thermocouple - Google Patents

Description

Thermocouple installation structure

The present invention relates to a thermocouple mounting structure, and more particularly to a mounting structure of a thermocouple when a precious metal thermocouple is mounted during temperature measurement of a platinum glass melting apparatus.

The most widely used temperature detectors in the industry are thermocouples. There are many types of thermocouples used as temperature detectors, which are suitable for measuring the temperature range of the object. In the temperature measurement of high temperature, precious metal thermocouples such as platinum-platinum-ruthenium alloy are used (refer to the non-patent literature). 1).

The noble metal thermocouple system is used for measuring the temperature of each measurement target portion of the device, for example, in a platinum glass melting device for glass manufacturing.

When the thermocouple is used in the platinum glass melting apparatus, it is generally a case where the thermocouple is directly welded to the measurement target portion, or a plate to which the thermocouple is welded and attached to the measurement target portion in advance (for example, refer to Patent Document 1) . Specifically, as shown in Fig. 1, in the measurement target portion of the platinum glass melting apparatus 1, the filaments 2 and 3 of the thermocouple C are welded and joined. Further, as shown in Fig. 2, the sleeve insulating tube 5 is connected to a temperature monitoring device (not shown) on the prime wires 2, 3.

In this way, when the thermocouple is directly welded to each measurement target portion, the operation of the insulating tube is involved, or the installation operation of the platinum glass melting device, the glass melting operation, etc., sometimes the thermocouple is broken. The situation. Therefore, for the thermocouple in which the disconnection occurs, the welding operation must be performed again.

[First technical literature] [Patent Literature] [Patent Document 1] Japanese Patent Laid-Open No. Hei 5-175555 [Non-patent literature] Non-Patent Document 1

Precious Metals Chemistry Application Section Revised Edition Published on December 15, 2001, published by Tanaka Precious Metal Industry Co., Ltd., pp. 121-131.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a mounting structure for a thermocouple that prevents a thermocouple from being broken when a thermocouple is directly welded to a measurement target portion in a platinum glass melting apparatus.

The present invention relates to a thermocouple mounting structure for joining and mounting a thermocouple in a measurement target portion of a platinum glass melting apparatus, characterized in that a prime wire for fixing a bonded thermocouple is provided in an upper portion or a vicinity of a measurement target portion. Reinforce the component.

The thermocouple has a very thin wire diameter, so the welded portion itself is small, and the strength of the welded portion tends to be less. Further, when heat is applied by welding, the metal structure of the plain wire is coarsened on the welded portion of the thermocouple wire, and has a tendency to be different from the metal structure of the plain wire except the welded portion, and is easy to The coarse crystal grain boundaries are cut. Further, when the platinum-based noble metal thermocouple is a platinum-palladium-ruthenium alloy, the platinum wire has a smaller tensile strength than the platinum-ruthenium alloy wire, and therefore, the platinum wire tends to be easily cut. Therefore, in the present invention, the thermocouple element is fixed to the upper portion or the vicinity of the measurement target portion so that the direct external force is not applied to the welded portion of the thermocouple, whereby the thermocouple can be surely prevented from being broken.

The reinforcing member in the mounting structure of the thermocouple of the present invention is preferably a platinum plate. The reinforcing member in the present invention is not particularly limited in shape, material, and the like, but it is preferable to not exert a large influence on the temperature measurement characteristics of the thermocouple. In particular, it is preferable to minimize the temperature difference between the welded portion and the reinforcing member. small. When the reinforcing member uses the platinum plate of the plate body, it is the same as the constituent material of the platinum glass melting device, and has little influence on the temperature measurement characteristics of the thermocouple. Further, although the method of fixing the thermocouple by the platinum plate is not particularly limited, for example, the thermocouple may be directly welded and joined to the measurement target portion, and the portion of the thermocouple wire extending from the joint portion may be crawled on the measurement target portion. The surface of the vicinity is covered with a platinum plate, and the end of the platinum plate is fixed by welding or the like.

In the mounting structure of the thermocouple of the present invention, the type of the thermocouple is not particularly limited, but it is effective when using a noble metal thermocouple for measurement in a high temperature range. The noble metal thermocouple has a platinum group. Specifically, there are Pt to Pt-Rh 10%, Pt to Pt-Rh 13%, Pt-Rh 6% to Pt-Rh 30%, and Pt-Rh 20% to Pt-Rh 40%. The present invention is particularly effective when Pt is used for Pt-Rh alloy thermocouples.

When the present invention is used, even if the thermocouple is directly welded, the thermocouple can be surely prevented from being broken at the measurement target portion in the platinum glass melting apparatus.

Hereinafter, embodiments of the present invention will be described in detail with reference to the first embodiment and the second embodiment.

(Example 1)

Fig. 3 is a side view (A) and a plan view (B) showing the state in which the thermocouple of the first embodiment is mounted. In the first embodiment, the thermocouple C is directly welded to the measurement target portion of the platinum glass melting apparatus 1 for temperature measurement. The thermocouple C is composed of a platinum wire 2 having a wire diameter of 1 mm and a Pt-Rh 13% wire of the same wire diameter.

After the thermocouple tip side is welded, a square platinum plate 6 having a thickness of 0.5 mm and a side of 1 cm is used as a reinforcing material in the vicinity of the welded portion 4, so that the platinum plate 6 covers the Pt element line 2 and the Pt-Rh 13% element line 3 Locally, the four corners of the platinum plate 6 are fixed by welding.

Further, as shown in Fig. 4, after the platinum plate 6 is fixed, a plurality of aluminum insulating tubes 5 are fitted to the Pt element line 2 and the Pt-Rh 13% element line 3 to mount the thermocouple.

When the mounting structure of the thermocouple of the first embodiment and the mounting structure of the prior thermocouple (refer to FIGS. 1 and 2) were compared, in the prior mounting structure, when the insulating tube was fitted, the welded portion 4 was cut. In the case, but in Embodiment 1, the disconnection situation does not occur at all.

Moreover, when fifty sets of thermocouples are installed in the measurement object portion of the platinum glass melting apparatus, in the previous installation structure, in the apparatus assembly operation or the glass melting operation, there will be fifty groups. Five groups of thermocouples were disconnected. On the other hand, in the mounting structure of the first embodiment, all of the fifty sets of thermocouples did not break.

(Example 2)

Fig. 5 is a side view (A) and a plan view (B) showing the state in which the thermocouple of the second embodiment is mounted. In the second embodiment, the thermocouple C was directly welded and joined to the measurement target portion of the platinum glass melting apparatus 1 for temperature measurement in the same manner as in the first embodiment. The thermocouple C is the same as that of the first embodiment.

After welding on the tip side of the thermocouple, a square platinum plate 6 having a thickness of 0.5 mm and a side of 1 cm is used as a reinforcing material, so that the platinum plate 6 covers the welded portion 4, so that the welded portion 4 is located at the center of the reinforcing material, and then the platinum plate is welded and fixed. The four corners of 6.

Further, as shown in Fig. 6, after the platinum plate 6 is fixed, a plurality of aluminum insulating tubes 5 are placed in the Pt element line 2 and the Pt-Rh 13% element line 3, and the thermocouple is mounted.

When the mounting structure of the thermocouple of the second embodiment and the mounting structure of the prior thermocouple (refer to FIGS. 1 and 2) are compared, in the prior mounting structure, when the insulating tube is fitted, the welded portion 4 is cut off. In the case, but in Embodiment 2, the disconnection situation does not occur at all.

Moreover, when fifty sets of thermocouples are installed in the measurement object portion of the platinum glass melting apparatus, in the previous installation structure, in the apparatus assembly operation or the glass melting operation, there will be fifty groups. Five groups of thermocouples were disconnected. On the other hand, in the mounting structure of the second embodiment, all of the fifty sets of thermocouples did not break.

[Industrial Availability]

When the present invention is used, when the thermocouple is directly welded to the platinum glass melting device, the thermocouple can be prevented from being broken, so that the maintenance work of the platinum glass melting device can be reduced, and stable glass melting can be realized. operating.

1. . . Platinum glass melting device

2,3. . . Prime line

4. . . Fusion joint

5. . . Insulating tube

6. . . Platinum plate

C. . . Thermocouple

Fig. 1 is a side view (A) and a plan view (B) showing a state in which a conventional thermocouple is mounted.

Figure 2 is a side view showing the state in which the previous thermocouple was mounted.

Fig. 3 is a side view (A) and a plan view (B) showing the state in which the thermocouple of the first embodiment is mounted.

Fig. 4 is a side view showing the state in which the thermocouple of the first embodiment is mounted.

Fig. 5 is a side view (A) and a plan view (B) showing the state in which the thermocouple of the second embodiment is mounted.

Fig. 6 is a side view showing the state in which the thermocouple of the second embodiment is mounted.

1. . . Platinum glass melting device

2. . . Prime line

3. . . Prime line

4. . . Fusion joint

6. . . Platinum plate

C. . . Thermocouple

Claims (2)

A thermocouple mounting structure for joining and mounting a thermocouple in a measurement target portion of a platinum glass melting apparatus, wherein a reinforcing member for fixing a prime wire of a bonded thermocouple is provided at an upper portion or a vicinity of a measurement target portion, And the aforementioned reinforcing member is a platinum plate. The thermocouple mounting structure according to the first aspect of the invention, wherein the thermocouple is a platinum-plated platinum-rhodium alloy.