JP2990326B2 - Mounting structure of sheath thermocouple - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a sheath thermocouple (hereinafter referred to as a sheath thermocouple).
Sometimes referred to simply as “thermocouple”. ) To a boiler tube. In particular, when attaching a thermocouple to a boiler tube that is exposed to a high-temperature atmosphere and a corrosive atmosphere such as sulfur oxides, such as a boiler tube in a heavy oil / coal boiler in a power plant, and is likely to generate vibrations due to cavitation phenomena, etc. This is a preferred invention.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 1, a thermometer 12 of a thermocouple 12 is directly welded on a water pipe 16 to a water pipe 16 by attaching it to a water pipe (boiler tube) disposed in a boiler in a thermal power plant. (Since the temperature measurement object is destroyed by the usual arc welding at the site), the temperature measurement unit 14 is resistance-welded to the pad 18 at the factory, and the pad 18 is welded to the surface of the water pipe 16 at the site. (Refer to the conventional drawing in Japanese Utility Model Laid-Open No. 1-81544).

In order to measure the outer peripheral surface temperature at each site, 40 to 90 thermocouples of various lengths each ranging from 4 to 50 m are attached.

[0004] Then, the water pipe of the boiler of the thermal power plant is
Exposure to high temperatures and corrosive atmospheres as described above corrodes the boiler tube and sometimes necessitates a partial replacement of the boiler tube. In this case, 5 to 10 m is cut around the corroded portion of the tube. At this time, thermocouples are much more expensive than tubes (50,000 to 250,000 per tube)
Therefore, it is desirable to reuse.

In this case, it is conceivable to use a temperature measuring device having the following configuration as shown in FIGS.

[0006] The pad 20 fixed to the object to be measured (water tube) 16, the fixing metal 22 fixed to the tip portion (temperature measuring part) 14 of the thermocouple 12, and the pad 20 and the fixing metal 22 are detachably attached to each other. Temperature measuring device characterized by having a possible fitting means. "

[0007]

However, the fitting means having the above-described structure includes a fixing bracket 22 having a U-shaped cross section,
The pad 20 is formed in a tunnel shape, and the fixture 22 is dimensioned to stop in the pad and fit without permission. The U-shaped cross section of the fixture 22 (the bent portion 28 formed on the distal end side through the notch 26). ) Ru der which closely fixed by plastically deforming the.

[0008]

However, it has been found that the thermocouple mounting structure has the following problems.

(1) When the water pipe 16 is replaced, the U-shaped fixing bracket 22 is usually corroded (in particular, the bent portion 2
When the U-shaped fixture 22 is removed from the tunnel-shaped pad 18, the U-shaped fixture 22 is damaged and cannot be reused. For this reason, it is necessary to remove the U-shaped fixing bracket 22 from the thermocouple temperature measuring section 14. At this time, the thermocouple temperature measuring section 14 is easily damaged, and the thermocouple 1 is hardly damaged.
2 cannot be reused.

(2) As in the case of the conventional temperature measurement performed through the pad 18 shown in FIG. 1, the temperature is measured through the fixture 22 and the tunnel-shaped pad 2 is subjected to high-temperature corrosion.
Rattling occurs between the 0 or U-shaped fixture 22;
Stability of temperature measurement (particularly during water tube vibration) is impaired.

In view of the above, it is an object of the present invention to easily cut and replace a boiler tube to which a thermocouple is attached without damaging a temperature measuring portion of the thermocouple. Another object of the present invention is to provide a thermocouple mounting structure that is excellent in temperature measurement stability of a thermocouple to a boiler tube.

[0012]

Means for Solving the Problems The present inventors have made intensive efforts to solve the above-mentioned problems, and as a result, have arrived at a thermocouple mounting structure having the following structure.

[0013] A mounting structure for mounting a sheath thermocouple to a boiler tube, the pad being welded and fixed to an outer peripheral surface of the tube, and having a cut portion capable of inserting and abutting a temperature measuring portion of the sheath thermocouple in a tube bus direction. And a holding means for holding and fixing the temperature measuring section to the outer peripheral surface of the tube on the pad, wherein the holding means slides with the holding block on both sides of the cut portion of the pad so that the block can be undercut and connected by chance. wall is formed, in a state of inserting the temperature measuring portion of the sheath thermocouple to cut portion, the holding block is Bed <br/> lock retaining wall hitting write Marete from the side, in holding block
The temperature measuring section is fixed to the outer peripheral surface of the tube by pressing .

[0014]

The operation and effect of the present invention are as follows.
With the above configuration, the following operation and effect can be obtained.

[0015] (1) the cut portion of the pad, while being arranged temperature measuring unit of the thermocouple, Nde tapping write a chisel or the like holding block from the side of the block retaining wall, holding block
The temperature measuring unit by pressing fixed to the tube outer peripheral surface in,
Result of the temperature measuring part being pressed directly to the temperature measuring point of the boiler tube
Becomes Moreover, even if the presser block is corroded during use,
Its corrosion block corner is the main, pressing wall (Block
The holding block (spacer block) is pressed by the holding wall in a face-to-face manner, and the temperature measuring part of the thermocouple is
Since the presser block (spacer block) is pressed down at the center of the lower surface, the temperature measuring section does not rattle in relation to the temperature measuring point of the boiler tube.

Therefore, the mounting structure of the thermocouple of the present invention is as follows.
The thermocouple has excellent temperature measurement stability for the boiler tube and also has excellent durability. .

(2) When the boiler tube is corroded and needs to be replaced, the holding block is detached from the holding wall by beating the boiler tube from the side in the opposite direction of the insertion direction with a rag or the like. Can be. For this reason, the thermocouple mounting structure of the present invention can easily remove the thermocouple from the boiler tube without damaging the thermometer of the thermocouple. Therefore, the thermocouple can be reused. Further, corrosion of the presser block to the presser surface rarely progresses, and the presser block can be reused, which is economical as a whole.

(3) As shown in FIG.
With the temperature measuring section 14 of the thermocouple 12 inserted and arranged in the tunnel-shaped insertion section 32 formed in the notch of the thermocouple 12, the distal end of the temperature measuring section is prevented from coming off with the small screw 34, and the middle is set with the holding screw 36. There is also a thermocouple mounting structure configured to be held down by the tip of the thermocouple. However, the mounting structure of the thermocouple is basically such that the screw portion prevents the thermocouple from coming off and pressing. Therefore, the number of steps for attaching / removing the thermocouple increases, and it becomes impossible to attach / detach due to corrosion. Therefore, the above-mentioned problems to be solved by the present invention still remain.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The same parts as those in the conventional example are denoted by the same reference numerals, and all or part of the description thereof will be omitted.

(1) Embodiment 1 (FIGS. 5 to 7) In this embodiment, a thermocouple 12 is connected to a boiler tube (water tube) 16.
In a mounting structure for mounting to the tube, a pad 44 having a cutout portion 42 which is welded and fixed to the outer peripheral surface of the tube 16 and in which the temperature measuring portion 14 of the thermocouple 12 can be inserted and abutted in the tube generatrix direction, and The superordinate concept is that the structure includes a holding means for holding and fixing the warm part 14 to the outer peripheral surface of the tube.

In the above configuration, the holding means is provided on both sides of the notch 42 of the pad 44 with a holding block (pressing block ).
The lock body 46 and the spacer block 54) are formed with a block holding wall 48 that can be slidably and undercut-coupled to the block body . The holding block 46 is held in a state where the temperature measuring unit 14 of the thermocouple 12 is inserted into the cutout 42. Tap into wall 48 and measure with holding block (spacer block 54).
The configuration is such that the warm part 14 is pressed and fixed to the outer peripheral surface of the tube 16 .

Specifically, the presser block is
And click body 46, disposed on the lower surface of the presser block body 46
Is made engageable and by spacer blocks 54 by presser block 46 and the engaging projection 48 / recess 52 means,
On the lower surface of the spacer block 54 , the thermocouple temperature measuring section 14 is held and fixed (pressed and fixed ) to the outer peripheral surface (temperature measuring point) of the tube. Also, although not necessarily, the engagement rib 56 of the block retaining wall 48 is inclined downwardly engagement surface is a lower surface toward the tip, the presser block, i.e., the spacer block 5
The pressing force of the thermocouple 4 toward the tip 4 increases.

The mode of use of this embodiment is as described in the section of the operation and effect described above.

(2) Second Embodiment (FIGS. 8 to 10) Basically, it is the same as the first embodiment. Parts corresponding to those in the first embodiment are denoted by the same reference numerals with the suffix A, and a part of the description thereof is omitted.

In this embodiment, the holding block is a wedge-shaped block 46A, and the block holding wall 48A has a ceiling portion (engaging portion) 56A whose lower surface is inclined downward toward the tip. is a type,
Tuning the thermocouple temperature measuring section 14 on the lower surface of the wedge-shaped block 46A
It is configured to be fixed to the outer peripheral surface (temperature measuring point) by pressure contact . The ceiling portion 56A of the block holding wall 48A is slightly steeper than the inclination of the wedge-shaped block 46A, and the wedge-shaped block (holding block) 56A is moved toward the distal end, so that the thermocouple temperature measuring section 1
4 is increased.

The mode of use of this embodiment is as described in the above-mentioned section of the operation and effect.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a conventional general thermocouple mounting structure.

FIG. 2 is a perspective view showing a state before a thermocouple is inserted into a pad in a thermocouple mounting structure proposed in Japanese Utility Model Laid-Open No. 1-81544.

FIG. 3 is a perspective view of a main part in the same manner, in which the main body is inserted and fixed and attached.

FIG. 4 is a main part plan view showing a prior art example of a thermocouple mounting structure.

FIG. 5 is a main part plan view showing an example of a thermocouple mounting structure of the present invention.

FIG. 6 is a schematic sectional view taken along line 6-6 in FIG. 5;

FIG. 7 is a schematic sectional view taken along line 7-7 of FIG. 5;

FIG. 8 is a main part plan view showing another example of the thermocouple mounting structure of the present invention.

FIG. 9 is a schematic sectional view taken along line 9-9 of FIG. 8;

FIG. 10 is a schematic sectional view taken along line 10-10 of FIG. 8;

[Explanation of symbols]

12 (sheath) thermocouple 14 thermocouple temperature measuring section 16 water pipe (boiler tube) 42 pad cut section 44, 44A pad 46 holding block main body 46A wedge-shaped block 48, 48A block holding wall 50 engaging convex section 52 engaging concave section 54 Spacer block 56 Engagement spacer

Continuing on the front page (72) Inventor Shoichi Morimoto 4-33 Komachi, Naka-ku, Hiroshima City, Hiroshima Prefecture Inside Chugoku Electric Power Co., Inc. (72) Takahisa Nakata 4-33 Komachi, Naka-ku, Hiroshima City, Hiroshima Prefecture Chugoku Electric Power Stock In-company (72) Inventor Tsujihiko Yasuda 107-takanedai, Midori-ku, Nagoya City, Aichi Prefecture (72) Inventor Akiyoshi Hanano 230, Okita-cho, Nakamura-ku, Nagoya City, Aichi Prefecture Inside Chubu Sukegawa Kogyo Co., Ltd. (72) Inventor Tamuro Ito 230 Okita-cho, Nakamura-ku, Nagoya City, Aichi Prefecture Inside Chubu Sukegawa Kogyo Co., Ltd. (56) References JP-A-61-296229 (JP, A) JP-A-6-186087 (JP, A) -3435 (JP, U) Fully open sho 56-3436 (JP, U) Fully open sho 61-15531 (JP, U) Fully open sho 59-191630 (JP, U) (58) Fields investigated (Int. . ^6, DB name) G01K 1/14 G01K 7/02

Claims (3)

(57) [Claims] 1. A mounting structure for mounting a sheath thermocouple to a boiler tube, wherein the sheath thermocouple is welded and fixed to an outer peripheral surface of the tube, and a notch capable of inserting and abutting a temperature measuring portion of the sheath thermocouple in the tube bus direction. A pad having a portion, and holding means for holding and fixing the temperature measuring section to the outer peripheral surface of the tube on the pad, wherein the holding means is provided on both sides of the cut portion of the pad,
A block holding wall is formed which can be slipped and undercut-coupled to the presser block, and the thermometer of the sheath thermocouple is inserted into the cutout portion.
Slapping write Marete, the press but from the side to the block retaining wall
The temperature measuring part is pressed against the outer peripheral surface of the tube with a block.
A mounting structure for a sheath thermocouple characterized by being defined. 2. The holding block according to claim 1, wherein
Are located on the presser block body and the lower surface of the presser block body.
And a spacer block that can be engaged with the holding block and the engaging projection / recess means. The temperature measuring section is fixed to the outer peripheral surface of the tube by pressing on the lower surface of the spacer block. The mounting structure of the sheath thermocouple. 3. The tunnel type according to claim 1 , wherein the holding block is a wedge-shaped block, and the block holding wall has a ceiling portion (engaging portion) whose lower surface is inclined downward toward the front end. And the wedge-shaped block
The temperature measuring unit is fixed to the outer peripheral surface of the tube by pressure contact on the lower surface.
Mounting structure sheathed thermocouple, characterized in that that.