JPH08278206A - Furnace temperature detector - Google Patents

Abstract

PURPOSE: To obtain a furnace temperature detector for preventing a damage caused by thermal expansion and contraction. CONSTITUTION: A furnace temperature detector is provided with a lance tube 7 which can be expansibly and contractibly inserted toward the inside of a furnace in a housing whose edge part comes into contact with a furnace wall and a thermocouple tube 12 for housing and supporting a thermocouple in its inside. The circumferential part of the thermocouple tube 12 is disposed to be fixed and penetrated a partition wall 7a adjacent to the edge in the tube 7, and the thermocouple tube 12 is thermally, expansibly and contractibly supported on fixed support pieces 20, 22 in the lance tube 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an expandable furnace temperature detecting device used for detecting the temperature inside a boiler, a heat exchanger, a gasification furnace or the like.

[0002]

2. Description of the Related Art When detecting the temperature inside a furnace such as a boiler, a heat exchanger, or a gasification furnace, it is generally placed in contact with a wall box on the furnace casing in order to avoid thermal influence on the structure of the temperature detecting device. There is used a temperature detecting device in which a lance tube having a thermocouple can be expanded and contracted into the furnace from the inside of the housing.

The structure of such a conventional furnace temperature detecting device will be described with reference to FIGS. 4 and 5. Reference numeral 1 is a wall box provided on a furnace wall 2a of a furnace 2 such as a boiler, and 2b is a furnace wall 2
The wall sleeve 3 provided in a has one end supported on the wall box 1 by a shaft 4 and the other end supported by a support 5 extending from a building or the like by a shaft 6, and 7 has a rear end in the housing 3. It is a lance tube fixed to the traveling carriage 8 and supported at its tip by a support roller 9 so as to be extendable and retractable (horizontal movement) toward the inside of the furnace 2.

The head valve 1 has a tip end slidably inserted into the traveling carriage 8 and the lance tube 7 and a rear end fixed to a housing rear end wall.
1 is a feed tube connected to 1, and 12 is a thermocouple tube for accommodating and supporting a thermocouple 13, which will be described later, which is provided in the lance tube 7 in parallel with the feed tube 10 with a gap.
Through the chain sprocket mechanism 15a, 15b, etc.,
It is a drive motor on the housing 3 that drives the traveling carriage 8 part to reciprocate.

When the drive motor 14 is actuated, the traveling carriage 8 connected via the chain sprocket mechanisms 15a, 15b and the like moves by the guide roller 16 while coming into contact with the track portion in the housing 3, and the tip portion of the lance tube 7 is moved. It expands and contracts to the position inside the furnace. Thermocouple 13 together with this lance tube 7 is thermocouple tube 1.
The temperature inside the furnace is detected and transmitted to a measuring unit (not shown). At this time, air is sent from the feed pipe 10 to the lance tube 7 to cool the lance tube 7. Then, this air is released to the outside of the lance tube 7 obliquely rearward from a nozzle (not shown) provided in the lance tube 7.

FIG. 6 shows the inside of the lance tube 7 described above.
A detailed structure is shown. The lance tube 7 has a thin plate on the distal end side in order to reduce bending and the like due to its own weight during long expansion and contraction.
The plate thickness on the rear end side is thickened. The feed tube 10 is eccentrically inserted into the lower side of the lance tube tube 7.
A partition 7a is provided inside the lance tube 7 at a position slightly forward of the tip of the feed tube 10 in a state where the lance tube 7 is most retracted.

The thermocouple tube 12 is disposed in contact with the upper side of the lance tube 7 so as to pass through the opening 17 of the partition wall 7a, and is plug-welded 18 from the outside of the lance tube 7 at fixed intervals in the length direction to form the lance. It is fixed to the tube 7. The thermocouple 13 is fixedly held on the tip of the thermocouple tube 12 by protruding from the tip of the lance tube 7 for a certain distance, and the rear side of the thermocouple 13 is configured to follow the movement of the lance tube 7 by an automatic winding system or the like. Has been done.

[0008]

In the case of the above-mentioned conventional apparatus, when the lance tube 7 is inserted into the furnace, the lance tube 7 is directly exposed to the high temperature in the furnace and the feed tube 1.
A difference in thermal expansion in the lengthwise direction occurs between the thermocouple tube 12 cooled by 0 air. Then, there is a problem that a large bend is generated on the side of the thermocouple tube 12 or the spot welded portion 18 is cut off, which obstructs the follow-up of the rear side of the thermocouple 13 and damages it.

[0009]

In order to solve the above problems, a lance tube is provided in a housing whose front end is in contact with the furnace wall so that the lance tube can be expanded and contracted toward the inside of the furnace, and a thermocouple is housed and supported therein. In the in-furnace temperature detection device equipped with a thermocouple tube, the thermocouple tube is arranged through the partition wall of the lance tube by fixing the outer periphery to a partition wall near the tip of the lance tube, and the thermocouple tube is thermally expandable in the lance tube. It is configured to be supported on the fixed support piece.

[0010]

In the above invention, when the lance tube 7 moves in and out of the furnace 2 and is heated and thermally expanded, the intervals between the plurality of fixed support pieces on the lance tube 7 change. At this time, since the thermocouple tube 12 slides on each fixed support piece and can relatively move in the length direction, the thermocouple tube 12 is not bent and is not bent.

As a result, cutting of the mounting portion, poor tracking of the thermocouple, and damage to the thermocouple are eliminated.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in FIGS. FIG. 1 is a partial vertical cross-sectional view of a lance tube portion according to an embodiment corresponding to FIG. 6, and FIG. 2 is an IV of FIG.
~ A cross-sectional view taken along the line IV, and Fig. 3 is an enlarged explanatory view of a V portion in Fig. 1. 1 to 3, the same elements as those of the related art are denoted by the same reference numerals, and overlapping description will be omitted.

In FIG. 1, reference numeral 20 denotes a cylindrical shape for fixing the thermocouple tube 12 at fixed intervals by plug welding 21 or the like on the lance tube 7 so that the thermocouple tube 12 is loosely slidably inserted and supported. The fixed support piece 22, is a semi-cylindrical fixed support piece 23 which has an end fixed to the inner surface of the rear end flange of the lance tube 7 by welding or the like and slidably supports the rear free end of the thermocouple tube 12. Is a fixing portion that fixes the outer peripheral portion of the thermocouple tube 12 and the partition wall 7a by welding or the like while penetrating the partition wall 7a of the lance tube 7.

The thermocouple 13 is fixed to the tip of the thermocouple tube 12 while protruding from the tip of the lance tube 7 by a certain length, and the rear side passes through the thermocouple tube 12 and is automatically provided outside the lance tube 7. A mechanism such as a winding system is provided so as to follow the movement of the lance tube 7.

With this configuration, when measuring the temperature in the furnace,
The lance tube 7 is driven by the drive motor 14 in FIG.
However, when it goes in and out of the furnace 2, it thermally expands and contracts. That is, while the distance between the lance tube 7, the cylindrical fixed support piece 20 and the semi-cylindrical fixed support piece 22 varies, the thermocouple tube 12 slides on each fixed support piece 20 and 22 in the longitudinal direction. However, the thermocouple tube 12 is not bent and is not bent.

Further, as a result, breakage of the plug welded portion 21 and the fixed portion 23, follow-up failure of the thermocouple 13 and damage to the thermocouple 13 as in the conventional case are eliminated.

[0017]

As described above, according to the present invention, the thermocouple tube is disposed through the partition wall near the tip of the lance tube with its outer peripheral portion fixed, and the thermocouple tube is thermally expandable in the lance tube. It is configured to be supported on the fixed support piece. This eliminates the occurrence of bending of the thermocouple tube and breakage of the mounting portion due to the difference in thermal expansion between the lance tube 7 and the thermocouple tube. Therefore, it is possible to reliably prevent the thermocouple from following the failure and damage it, and to improve the operation efficiency.

[Brief description of drawings]

FIG. 1 is a partial vertical sectional side view of an embodiment of the present invention.

FIG. 2 is a transverse sectional view taken along line IV-IV in FIG. 1 of the same embodiment.

FIG. 3 is an enlarged view of a V portion of FIG. 1 of the same embodiment.

FIG. 4 is a side view showing an overall configuration of a conventional example.

FIG. 5 is a schematic perspective view of FIG.

FIG. 6 is a vertical cross-sectional side view of a lance tube portion of the conventional example.

[Explanation of symbols]

 1 Wall Box 2 Furnace such as Boiler 2a Furnace Wall 2b Wall Tube 3 Housing 4, 6 Axis 5 Housing Support 7 Lance Tube 7a Partition Wall 8 Traveling Carriage 9 Support Roller 10 Air Feed Tube 11 Head Valve 12 Thermocouple Tube 13 Thermocouple 14 Drive motors 15a, 15b Chain sprocket mechanism 16 Guide roller 20 Cylindrical fixed support piece 21 Plug welded portion 22 Semi-cylindrical fixed support piece 23 Welded fixed portion

Claims (1)

[Claims] 1. An in-furnace temperature detecting device equipped with a lance tube provided in a housing whose front end is in contact with the furnace wall so that the lance tube can be expanded and contracted toward the inside of the furnace, and a thermocouple tube for accommodating and supporting a thermocouple therein. In the above, the thermocouple tube is pierced by fixing the outer peripheral portion to a partition wall near the tip in the lance tube, and the thermocouple tube is supported on a fixed support piece in the lance tube so as to be thermally expandable and contractible. Characteristic furnace temperature detection device.