JPH0122108Y2 - - Google Patents

Description

[Detailed description of the invention] This invention proposes that when performing high temperature measurement using a sheathed thermocouple, most of the sheath is heated to a high temperature, or the middle part of the sheath is heated to a higher temperature than the temperature sensing part located on the object to be measured. The present invention relates to a high temperature measurement device equipped with a cooling means that can be used particularly effectively under temperature measurement conditions such as exposure to high temperatures.

Conventionally, when the temperature of an object moving in a high-temperature furnace such as a heating furnace or soaking furnace is continuously measured using a thermocouple, or when the middle part of the thermocouple is located near the heat source, large temperature measurement errors occur. It is known that
The cause of this is also a so-called shunt error, which is due to a decrease in insulation resistance at high temperatures of the insulation between the thermocouple wires of the thermocouple exposed to the high temperature part and between the wire and the sheath. It has been clarified. Therefore, as a countermeasure against shunt errors, a cooling gas flow path is provided concentrically at an arbitrary portion in the length direction of the thermocouple a shown in FIG. An example in which a pipe b is provided is known. Although a temperature measuring device having this structure is effective when used in a relatively short and straight state, it has various problems when used in a long length and in a bent position. For example, in the case of a long structure, it becomes necessary to arrange thermocouple support members at required intervals to prevent the thermocouple and the protection tube from coming close to each other or coming into contact with each other. The problem is that the thermocouple and the protective tube come close to each other or come into contact with each other at the bent part when used bent, and that part becomes extremely high temperature. Then a problem is presented.

The present invention was developed in view of the above-mentioned problems, and its purpose is to have a uniform cooling effect regardless of whether the cooling part is long or short, or straight or curved, and to provide a mechanical cooling effect. The purpose of the present invention is to provide a high temperature measurement device equipped with a cooling means having an integrated structure that is strong and easy to handle. In a high temperature measurement device that is installed airtight through the protection tube, an independent tube body that serves as a cooling gas flow path from the inlet to the outlet of the protection tube is interposed between the inner surface of the protection tube and the outer surface of the sheathed thermocouple or the inner surface of the protection tube. In this high temperature measuring device, a plurality of tubes are arranged in parallel so as to be in contact with the inner surface of the heat insulating layer and the outer surface of the sheathed thermocouple, and these tubes continuously support the sheathed thermocouple.

The details of the present invention will be explained below based on the embodiment shown in the drawings. Figure 2 shows a typical embodiment of the present invention. A sheathed thermocouple 4 is airtightly disposed through the cylindrical protection tube 3, and the flow of the protection tube 3 is carried out within the protection tube 3 with the temperature measurement part 5 protruding from the tip of the protection tube 3. A cooling gas flow path 6 is formed from the inlet 1 to the outlet 2, and the cooling gas flow path forming member 7 continuously supports the sheathed thermocouple 4. The cooling gas flow path forming member 7 in FIG. The cooling gas flowing in from the flow path forming member 7 flows out from the outlet 2 through the pipe 8 as the flow path forming member 7 and the gap 7 between these members. As shown in an embodiment in FIG. 3, the tube body 8 has two passage forming members at opposing positions in order to continuously support at least the sheathed thermocouple 4 inside the protective tube 3. It is necessary to provide a tube 8 as a sheathed thermocouple 7, and preferably three more than two tubes 8, as shown in the figure.
An outer cover support structure is adopted in which the flow path forming member 7 covers and supports the entire outer periphery of the flow path forming member 7. The sheathed thermocouple 4, the tubular body 8 as the flow path forming member 7, and the protective tube 3 are reduced in diameter as a whole as shown in the cross-sectional view of FIG. Close contact can be made with the surface of the path forming member 7. In this case, since the contact area between the tube 8 and the sheathed thermocouple becomes large, the tube 8
The cooling effect on the sheathed thermocouple due to the cooling gas passing through it can be enhanced. Incidentally, in order to install such a flow path forming member 7 inside the protective tube 3 in which the sheathed thermocouple 4 as described above is airtightly disposed through the protective tube 3, the protective tube 3 end shown in FIG. 2 must be opened. The above-mentioned flow path forming member 7 is inserted from the open tube end, or the flow path forming member 7 is previously fixed to the outer surface of the sheath type thermocouple 4, and this integrated body is inserted into the above-mentioned protective tube 3. Appropriate items such as interior decoration are adopted. Therefore, it is desirable to use heat-resistant steel such as Inconel or stainless steel for the flow path forming member 7 due to the usage condition.
As in the embodiment shown in the figure, a heat insulating material 9 made of an inorganic material such as a paper-like material made of one or more of alumina, silica, zirconia, etc. is interposed between the flow path forming member 7 and the inner surface of the protective tube 3. It is also preferable to use the material of the flow path forming member 7 in order to avoid the influence from an external high temperature atmosphere when the high temperature measuring device is used under high temperature conditions. The embodiment shown in FIG. 5 is different from the embodiment shown in FIG.
This is an embodiment of a configuration in which the outlet 2 is formed at a similar end to the outlet 2 so as to prevent the cooling gas from being ejected into the interior of a heating furnace, soaking furnace, etc. in a high-temperature atmosphere whose temperature is to be measured. In the case shown in FIG. 5, the end of the tube body 8 is opened at a position such that at least a specific flow path forming member 7 can flow gas into the inlet of the protection tube 3, and communicates with this end. For example, a partition 10 is provided on the inflow port 1 side end, that is, on the right side in the figure, so that the end of the other tube body 8 on the outflow port 2 side does not communicate with the inflow port 1 of the protective tube 3, and the partition wall 10 is cut out. The end of this tube body 8 is exposed to the outlet 2 side, so that the inflow cooling gas from the inlet 1 can be sent to the outlet 2 formed on the same side as the inlet 1. Such a tube 8 on the inlet 1 side and a tube 8 on the outlet 2 side
In the case where the flow path forming members 7 are provided separately, it is necessary to place certain of the plurality of flow path forming members 7 on the inlet 1 side and the others on the outlet 2 side.

As described above, the high temperature measuring device according to the present invention is a high temperature measuring device in which a sheathed thermocouple is airtightly disposed through a protective tube having an inlet and an outlet for cooling gas. A plurality of independent tubes extending to the outlet and serving as a cooling gas flow path are placed in contact with the inner surface of the protection tube and the outer surface of the sheathed thermocouple, or the inner surface of the heat insulating layer interposed on the inner surface of the protection tube and the outer surface of the sheathed thermocouple. In addition to being arranged in parallel, these tubes continuously support the sheathed thermocouple, and the protection tube and tube body are made independent of each other, giving flexibility to the protection tube. This makes it possible not only to use the protection tube in a straight state, but also to use it in a bent position. Therefore, for example, it is possible to continuously measure the temperature of a moving object by sequentially extending the measuring device, which has been bent in advance, in response to the movement of the moving object. Furthermore, since the protective tube can be bent freely, it is extremely easy to handle. Since the outer surface of the sheathed thermocouple is wrapped with a cooling gas flow path forming member and the flow path forming member is protected either directly or by interposing a heat insulating material, the cooling gas can be supplied uniformly and steadily. In combination with the heat insulating effect of the heat insulating material, it has an excellent cooling effect to prevent shunt errors, and even when used in a bent position, the cooling effect is not impaired in any way.

Moreover, when this device is used with the device bent, the sheathed thermocouple is continuously supported inside the protective tube, so there is no problem with the cooling effect. The sheath type thermocouple is always held at approximately the center position inside the protection tube, and as the sheath type thermocouple is in contact with or close to the inner surface of the protection tube, the heat influence from the outside is reduced. This does not strongly affect the bent portion of the thermocouple. Further, since there is no support member that obstructs the gas flow in the gas flow path, it is possible to constantly supply the cooling gas and maintain a uniform cooling effect. In addition, the tube body arranged in parallel between the sheathed thermocouple and the protection tube also functions to increase the mechanical strength of this device, and prevents the protection tube from deforming against external pressure acting on the protection tube. You can also do it. Furthermore, since the sheath type thermocouple is supported by a plurality of tube bodies independent of the protection tube, the cooling effect can be maintained even if a part of the protection tube is damaged.
Furthermore, by setting the gas outlet on the inlet side as shown in Figure 5, these cooling gases will not be sent into the heating furnace or soaking furnace that is the object of measurement.
This gas does not adversely affect the molten metal in the furnace, and the above-mentioned effects in the bent state can be maintained in the same way.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional explanatory diagram showing a conventional example, Fig. 2 is a cross-sectional explanatory diagram showing an embodiment of the present invention, Fig. 3 is a cross-sectional view taken along line A-A in Fig. 2, and Fig. 4 is a thermal insulation diagram in Fig. 2. FIG. 5 is a cross-sectional view of another example in which materials are used in combination. 1: Inlet, 2: Outlet, 3: Protection tube, 4: Sheath type thermocouple, 5: Temperature measuring section, 6: Cooling gas flow path,
7: Cooling gas forming member, 8: Pipe body, 9: Heat insulating material,
10: Partition wall.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A high temperature measuring device in which a sheathed thermocouple is airtightly inserted through a protection tube having an inlet and an outlet for cooling gas, from the inlet to the outlet of the protection tube. Multiple independent tubes that serve as cooling gas flow paths are arranged in parallel so that they are in contact with the inner surface of the protection tube and the outer surface of the sheathed thermocouple, or the inner surface of the heat insulating layer interposed on the inner surface of the protection tube and the outer surface of the sheathed thermocouple. At the same time, these tubes continuously support a sheathed thermocouple in a high temperature measuring device. 2. The high temperature measuring device according to claim 1 of the utility model registration claim, which is formed by pressing from the outer surface of the protective tube to reduce the diameter of the whole.