JPH11351972A - Temperature measuring device for heating furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly measure a temperature after a protective type is fitted with no measurement error caused by dislocation of the protective pipe at temperature measurement, by screwing the protective pipe provided with a spiral protruding streak on such an outer periphery where a temperature sensor is inserted into a furnace wall of a heating furnace for fixing. SOLUTION: A ceramics protective pipe 9 such as a mullite wherein a spiral protruding streak 8 is provided on an outer periphery with its tip end being acute is used, and an acute tip end part of the protective pipe 9 where a temperature sensor 5 is housed is pressed against an arbitrary place on the outer surface of a heat-insulating material 1 of a heating furnace, and screwed into a required depth. After screwing, a fixing nut 10 is screwed into the protective pipe 9, on the outer side of the heat-insulating material 1 for tightening, so that the protective pipe 9 is surely fixed to the heat-insulating material 1. Further, for sure fitting, an inorganic bonding agent may be applied on the outer periphery of the protective pipe 9. For easy screwing, depending on material and condition of the heat-insulating material, the heat-insulating material 1 may be provided with a base prepared in advance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature measuring device for a heating furnace, and more particularly to a temperature measuring device having a protective tube for protecting a temperature sensor for measuring the temperature in the heating furnace from the atmosphere in the furnace.

[0002]

2. Description of the Related Art When a temperature in a heating furnace is measured using a temperature sensor such as a thermocouple or a resistance temperature detector, the temperature sensor is usually used in a protective tube. This prevents the temperature sensor from being directly exposed to a flame or other generated gas, and can maintain the life of the sensor for a long time.

FIG. 2 shows a temperature measuring apparatus having the above-mentioned conventional protective tube, 1 is a heat insulating material forming a furnace wall of a heating furnace, 2 is a heating wire embedded in the inner surface of the heat insulating material 1, and 3 is a heat insulating material. A hole 4 for inserting a sensor, which is provided so as to penetrate the material 1 from the outside to the inside, 4 is a cylindrical protective tube for inserting a temperature sensor having a round tip inserted into the hole 3, and 5 is inside the protective tube 4. A stored temperature sensor 6 such as a thermocouple, which is a sheathed thermocouple, is a connection terminal portion for electrically connecting the temperature sensor 5 to a thermometer (not shown).

In order to attach the conventional protective tube 4 containing the temperature sensor 5 to the heat insulating material 1, the protective tube 4 coated with an inorganic adhesive 7 or the like on the outer periphery thereof is inserted into the hole 3 of the heat insulating material 1. And glue.

[0005] The sensor protection tube 4 is made of a metal such as stainless steel or a ceramic such as mullite. When the operating temperature exceeds the service temperature of the metal, or when the measuring section of the sensor is used. If there is a heating wire nearby, use a ceramic protective tube with excellent heat resistance and electrical insulation.

[0006]

However, the heat insulating material 1
Is relatively fragile, such as ceramic fiber, when the conventional mounting method applies a force to the protective tube 4 from the outside of the heat insulating material, the fixing position with respect to the heat insulating material 1 easily shifts. May occur.

[0007] In addition, there is a disadvantage that it usually takes one or more days for the adhesive to harden, and it is not possible to start temperature measurement until the adhesive hardens.

The present invention has been made to eliminate the above disadvantages.

[0009]

The temperature measuring device for a heating furnace according to the present invention comprises a temperature sensor and a protective tube provided with a spiral ridge on an outer peripheral surface of the temperature sensor, into which the temperature sensor is inserted. The protective tube is screwed into the furnace wall of the heating furnace and fixed.

In the temperature measuring apparatus for a heating furnace according to the present invention, a fixing nut is screwed into a portion of the protective tube screwed into the furnace wall and protruding outside the furnace wall. .

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

In the present invention, instead of the conventional protective tube 4, a ceramic protective tube such as mullite having a spiral ridge 8 on its outer peripheral surface and having an acute end as shown in FIG. 9 and press the acute-angled tip of the protective tube 9 containing the temperature sensor 5 to an arbitrary position on the outer surface of the heat insulating material 1 of the heating furnace and screw it to a required depth.

After the screwing, the fixing nut 10 is screwed and fastened to the protective tube 9 outside the heat insulating material 1 to securely fix the protective tube 9 to the heat insulating material 1. An inorganic adhesive may be applied to the outer periphery of the protective tube for more secure fixing.

Depending on the material and condition of the heat insulating material, a preliminary hole may be provided in advance in the heat insulating material 1 in order to facilitate screwing.

[0015]

According to the temperature measuring apparatus for a heating furnace of the present invention having the above-described structure, even when a protective tube is attached to a relatively brittle heat insulating material such as ceramic fiber, a force is applied to the protective tube from outside. Even if it is added, it does not relatively easily dislocate to the heat insulating material, so that the protective tube does not displace when measuring the temperature, causing no measurement error. There is a great benefit that measurements can be made.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view of a temperature measuring device for a heating furnace according to the present invention.

FIG. 2 is a vertical sectional side view of a conventional temperature measuring device for a heating furnace.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulation material 2 Heating wire 3 Hole 4 Cylindrical protective tube 5 Temperature sensor 6 Connection terminal part 7 Inorganic adhesive 8 Ridge 9 Protective tube 10 Fixing nut

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[Procedure amendment]

[Submission date] April 12, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

[0009]

A temperature measuring device for a heating furnace according to the present invention has a temperature sensor, a tip into which the temperature sensor is inserted is formed at an acute angle, and a spiral ridge is provided on an outer peripheral surface thereof . a protective tube, become more and fixing nut, characterized in that the protective tube the fixing nut is screwed to the portion protruding above furnace wall outside of the protective tube which is threaded into the furnace wall of the furnace .

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Deleted

Claims (2)

[Claims] 1. A temperature sensor and a protection tube provided with a spiral ridge on an outer peripheral surface into which the temperature sensor is inserted. The protection tube is screwed into a furnace wall of a heating furnace and fixed. A temperature measuring device for a heating furnace. 2. The temperature measuring device for a heating furnace according to claim 1, wherein a fixing nut is screwed into a portion of the protection tube screwed into the furnace wall, the portion protruding outside the furnace wall.