JPH0717926Y2 - Water pipe temperature detectors such as multi-tube once-through boilers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an improvement of a device for detecting the temperature of a water pipe heat transfer part in a multi-tube once-through boiler or the like.

[Prior Art] Generally, in a small multi-tube once-through boiler, there is a drawback that the canned water easily concentrates and scale easily occurs because the amount of retained water is small, and in order to eliminate this, A method of detecting a temperature by mounting a temperature measuring sensor such as a thermocouple or a thermistor on the heat transfer part of the can is adopted.

For example, a method of forming a bottomed hole in the thickness of the vertical water pipe on the combustion chamber side and inserting a temperature measuring sensor in the bottomed hole, that is, a method of directly attaching to the vertical water pipe is performed.

However, in this conventional method of directly attaching to the vertical water pipe, the fitting portion of the temperature measuring sensor, that is, the wall thickness portion of the vertical water pipe forms a phase, so that the water pipe wall is not damaged. Drilling the bottomed hole for inserting the temperature sensor requires not only advanced technology, but also the depth of the bottomed hole to be drilled is limited, and the best contact with the combustion gas is made. There was a problem that the temperature sensing part of the temperature measuring sensor could not be inserted into the heat transfer part of the vertical water pipe that becomes high temperature, and the target temperature of the vertical water pipe could not be detected accurately. There is also the problem that it is not possible to freely select hot points.Because a bottomed hole is drilled in the vertical water pipe of the boiler, which is a pressurized container, the wall thickness of the vertical water pipe is locally thinned and its strength is reduced. And the risk of damage due to corrosion, etc. There has been a problem that went to be large. In addition, the vicinity of the insertion hole into the bottomed hole of the temperature measuring sensor is exposed to the radiant heat of the combustion gas, so the vicinity of the insertion hole is locally heated by the radiant heat, and the target vertical water pipe There is a problem that it is not possible to accurately detect the temperature of, and it is not possible to detect the accurate amount of adhesion such as scale, and the durability is extremely low due to burnout of the temperature sensor near the insertion port. It has become a thing.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned problems, and it is possible to reliably measure the temperature of the vertical water pipe, and the temperature measurement point can be freely set according to the structure of the heat transfer surface. It is easy to process and install, and is reliable, and can maintain sufficient strength as a vertical water pipe in a boiler that is a pressurized container. It is intended to improve the durability of the temperature measuring sensor while improving the temperature.

[Means for Solving the Problems]

The present invention has been made to solve the above problems, and an upper wall and a lower wall are connected by a large number of vertical water pipes, and each vertical water pipe has an annular water pipe wall with a very small gap. , A multi-tube through-flow boiler having a structure in which a boiler outer wall is provided outside the annular water pipe wall at a distance, and an annular combustion gas passage is formed between the boiler outer wall and the annular water pipe wall. In the above, a substantially arcuate temperature-sensitive member fixed to the outer peripheral surface of the vertical water pipe in a horizontal state substantially orthogonal to the vertical water pipe, and a temperature measuring device tightly inserted and installed in a bottomed hole formed in the temperature-sensitive member. And a radiant heat prevention member for blocking radiant heat to the insertion opening portion is provided at the base end portion of the temperature-sensitive member and the bottomed hole insertion opening. There is.

[Embodiment] Hereinafter, a specific embodiment of the present invention will be described in detail with reference to the drawings.

First, referring to FIG. 8 and FIG. 9, an outline of an embodiment of a multi-tube type once-through boiler will be described. This type of boiler has an upper pipe header 1 serving as a vaporizing portion formed in an annular shape.
And a lower pipe header 2 which is also a ring-shaped water supply part and is connected by a large number of vertical water pipes 3, 3, ....
The respective vertical water pipes 3 are arranged in an annular shape with a very small gap 4, preferably about 2 mm, being held and arranged as an annular water pipe wall. And, in each vertical water pipe 3,
The fins 10, 10, ...
Is stuck. The fins 10 are in a state of holding a very small gap 4'between the surfaces of the adjacent vertical water pipes 3, respectively.

An annular boiler outer wall 5 that surrounds the annular water pipe wall is arranged outside the annular water pipe wall while maintaining an appropriate interval. An annular combustion gas passage 6 is formed between the boiler outer wall 5 and the annular water pipe wall.

Further, a combustion chamber 8 is formed inside the annular water pipe wall, and a combustion device 7 is arranged above the combustion chamber 8 and the combustion chamber 8 and the flue 12 are arranged below the combustion device 7. A partition wall 11 for partitioning is provided.

In the multi-tube once-through boiler configured as described above, the temperature sensing member 14 having a function as a protective member or a holding member for the temperature measuring sensor 16 including a thermocouple or thermistor for measuring the temperature of the vertical water pipe 3 is In a horizontal state substantially orthogonal to the vertical water pipe 3, it is fixed to the outer peripheral surface of the vertical water pipe 3 by welding or the like. The tip portion 14 'of the temperature sensitive member 14
Are arranged so as to be located on the surface of the vertical water pipe 3 facing the combustion chamber 8 that has the highest temperature. This tip 14 '
As a measurement point of the pipe wall temperature where is located, in measuring the pipe wall temperature of the vertical water pipe 3, in order to measure the pipe wall temperature of the vertical water pipe 3 efficiently and surely, on the side facing the combustion chamber 8. A portion where the heat exchange of the vertical water pipe 3 is most performed, the amount of heat transfer is large, and the wall temperature of the vertical water pipe 3 is the highest is preferable. Specifically, on the side facing the combustion chamber 8, an annular shape is provided. The position near the apex of the vertical water pipe 3 arranged as the water pipe wall is effective. Further, the base end portion 14 ″ of the temperature sensitive member 14 is
It extends from the tip portion 14 'along the surface of the vertical water pipe 3 in a substantially horizontal state, and is located at a position facing the gap 4 of the annular water pipe wall. Therefore, the temperature-sensitive member 14 has a relatively short length from the tip portion 14 ′ to the base end portion 14 ″, and has a substantially arcuate shape corresponding to the curved surface of the surface of the vertical water pipe 3.

Further, the temperature sensitive member 14 is formed with a bottomed hole 13 into which the temperature measuring sensor 16 is tightly inserted and installed in the central axis portion thereof. The bottomed hole 13 is formed up to the vicinity of the tip portion 14 'of the temperature sensing member 14, and the insertion port portion 13' of the temperature measuring sensor 16 is formed on the end face of the base end portion 14 "of the temperature sensing member 14. Therefore, the temperature measuring sensor 16 inserted from the insertion opening 13 'is tightly inserted and installed so that the temperature sensing portion (not shown) at the tip thereof is located at the bottom portion 13 "of the bottomed hole 13. Therefore, the temperature of the vertical water pipe 3 is surely measured.

Here, the temperature-sensitive member 14 will be further described with reference to FIGS. 4 to 7. As the temperature-sensitive member 14, for example, a rod-shaped member having a required length, that is, the temperature measuring sensor 16 is used.
Is cut into a length long enough to be inserted and installed tightly, and the required diameter is obtained from one end surface of the cut surface, that is, the end surface of the base end portion 14 ″ of the temperature sensitive member 14 (the temperature measuring sensor 16 is in a tight state. Hole with a diameter and depth sufficient for insertion and installation at 13)
On the other hand, the portion of the base end portion 14 ″ that is in contact with the vertical water pipe 3 is made into a slope at a required angle, and then formed into a substantially arcuate shape corresponding to the curved surface of the surface of the vertical water pipe 3. .
In this way, by forming the slope on the temperature sensitive member 14,
This is effective in facilitating the attachment to the surface of the vertical water pipe 3 and facilitating the insertion of the temperature measuring sensor 16.

Now, at the base end portion 14 ″ of the temperature sensitive member 14, the insertion opening of the bottomed hole 13 is formed.
A radiant heat prevention member 15 is provided to block the 13 'portion from being exposed to the radiant heat of the flame in the combustion chamber 8.
The radiant heat prevention member 15 has an insertion port for the temperature measuring sensor 16.
It is to prevent the radiant heat of the flame from being overheated in the vicinity of the 13 'part, and to prevent it from overheating.
Along the left-right direction of the drawing), the upper and lower portions of the temperature-sensitive member 14 are appropriately extended, and they are fixed by welding or the like at a height substantially the same as the height of the temperature-sensitive member 14.

Further, the fin 10 corresponding to the portion to which the temperature sensitive member 14 is fixed is provided with a notch 17 for inserting the temperature measuring sensor 16 into the bottomed hole 13. As a result, the temperature measuring sensor 16 is tightly inserted and installed from the combustion gas passage 6 side through the notch 17 into the bottomed hole 13.

The operation of the present invention having the above structure will be described. Combustion gas (including some flames) generated by ignition of the combustion device 7 is separated from the combustion chamber 8 by the gaps 4, 4 ,.
Through the gaps 4 ′, 4 ′, ... Between the vertical water pipes 3 and the fins 10 to the combustion gas passage 6, and the gaps between the vertical water pipes 3 formed near the lower header 2 (not shown). ) From flue 12
Flows out from the flue 12 to the outside. At this time, in the vertical water pipe 3, the side facing the combustion chamber 8 has the highest temperature, but the temperature sensing member 14 causes the temperature sensing portion (not shown) of the temperature measuring sensor 16 to be perpendicular to the combustion chamber 8 side. Since it is located on the surface of the water pipe 3, the temperature of the wall of the vertical water pipe 3 can be accurately detected. By using the electrical signal corresponding to the tube wall temperature detected in this way, it is possible to prevent local overheating of the heat transfer section, control the temperature, or reliably detect the scale adhesion condition on the heat transfer surface. It is also possible to issue an appropriate alarm when the temperature signal reaches a temperature corresponding to the allowable limit of scale attachment.

Further, since the radiant heat prevention member 15 that blocks the radiant heat to the insertion port 13 'of the temperature measuring sensor 16 is provided at the base end portion 14 "of the temperature sensitive member 14, the temperature measuring sensor 16 is locally heated. In addition, the temperature measuring sensor 16 is effectively prevented from being burnt in the vicinity of the insertion opening 13 '.

[Effect of Invention] As described above, according to this invention, the following unique effects can be obtained.

(1) The side facing the combustion chamber even if the gap between the vertical water pipes is narrow, such as the can body having the annular water pipe wall structure, particularly the can body having the one-row water pipe array structure. Since it can be installed very easily in the hottest part where the heat transfer is the most, it can detect a reliable temperature signal accompanying the temperature rise of the vertical water pipe, and can prevent overheating of the vertical water pipe and detect scale adhesion. Can be done. In addition, it is possible to prevent puncture of the can body by detecting the time-dependent measurement result that the scale above the allowable limit has adhered and issuing an alarm, and the temperature rise of the vertical water pipe due to the low water level. Also, it will respond extremely sensitively and can prevent the empty heating.

(2) Since the radiant heat prevention member that blocks radiant heat to the insertion port of the temperature measuring sensor is provided at the base end of the temperature measuring member, the temperature measuring sensor is not locally heated,
The target tube wall temperature can be accurately detected, and the durability of the temperature measuring sensor can be improved.

(3) Further, since it is not necessary to directly form a bottomed hole in the vertical water pipe, the temperature sensitive member can be easily and securely attached, and the vertical water pipe has strength as a vertical water pipe arranged in the can body of the boiler which is a pressurized container. It can be provided at a low cost without causing a decrease in

(4) Furthermore, maintenance can be performed very easily without requiring any skill, which is extremely effective for this type of temperature detecting device.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a front view of one embodiment, FIG. 2 is a right side view of FIG. 1, and FIG. 3 is an enlarged view of line AA of FIG. FIG. 4 is a cross-sectional view, FIG. 4 is a side view after the temperature-sensitive member is formed into a substantially arc shape, FIG. 5 is an end view of FIG. 4, and FIG. 6 is a side view before the temperature-sensitive member is formed into an arc shape. FIG. 7 is an end view of FIG. 6, FIG. 8 is a schematic vertical sectional view showing a multi-tube through-flow boiler embodying the present invention, and FIG. 9 is a schematic transverse sectional view thereof. 1 …… Upper heading 2 …… Lower heading 3 …… Vertical water tube 4 …… Gap 5 …… Boiler outer wall 6 …… Burning gas passage 13 …… Bottomed hole 13 ′ …… Insertion port 13 ″ …… Bottom 14 ...... Temperature-sensitive member 14 '... Tip 14 "... Base end 15 ... Radiation heat prevention member 16 ... Temperature sensor

Claims (1)

[Scope of utility model registration request] 1. An upper pipe header 1 and a lower pipe header 2 are connected by a large number of vertical water pipes 3, 3, ..., Each vertical water pipe 3 is arranged as an annular water pipe wall having a very small gap 4. A multi-tube flow-through having a structure in which a boiler outer wall 5 is provided outside the annular water pipe wall at a distance, and an annular combustion gas passage 6 is formed between the boiler outer wall 5 and the annular water pipe wall. In the boiler, the temperature-sensitive member 14 having a substantially arcuate shape is fixed to the outer peripheral surface of the vertical water pipe 3 in a horizontal state substantially orthogonal to the vertical water pipe 3.
And a temperature measuring sensor 16 tightly inserted and installed in a bottomed hole 13 formed in the temperature sensitive member 14, and the base end portion 14 ″ of the temperature sensitive member 14 has an insertion port 13 for the bottomed hole 13 ′ And a radiant heat prevention member 15 for blocking radiant heat to the insertion opening 13 ′ at the base end 14 ″, a water pipe temperature detecting device such as a multi-tube through-flow boiler.