JPH10332623A - Corrosion detector for boiler casing and water supply pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect corrosion of a boiler casing or a water supply pipe automatically and continuously so that an appropriate countermeasure can be taken in the early stage of corrosion. SOLUTION: A first electrode 2 is inserted into the water tube 1 of a boiler and a second electrode 3 is disposed on the outer circumference of the water tube 1 facing the first electrode 2. The first and second electrodes 2, 3 are connected with a corrosion decision unit 4 for detecting corrosion of the water tube 1 based on the level of a current flowing between both electrodes. The first and second electrodes 2, 3 are then inserted into a water supply pipe while being close to each other and connected with the corrosion decision unit 4 in order to detect corrosion in the water supply pipe based on the level of a current flowing between both electrodes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corrosion detecting device for detecting a corrosion state in a boiler can or a water supply pipe.

[0002]

2. Description of the Related Art The state of corrosion of a boiler can body is indirectly determined by directly observing the inside of the boiler or checking whether the pH value of the can water is within an appropriate range from water quality data. doing. Therefore, if the state of these corrosions is neglected for a long period of time, it is not known that the can body is corroded, and the corrosion causes puncture of the can body.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to automatically and continuously detect the state of corrosion in a boiler can or a water supply pipe, and to take appropriate measures in the early stage of corrosion. It is an object.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has a first electrode inserted into a water tube of a boiler, and a first electrode inserted into an outer peripheral portion of the water tube facing the first electrode. The first feature is that two electrodes are provided, the first electrode and the second electrode are connected to a corrosion determiner, and the state of corrosion of the water pipe is detected based on a current value flowing between the two electrodes. . In addition, the present invention provides that a plurality of first electrodes are provided along an axial direction of the water pipe, and a second electrode is provided on an outer peripheral portion of the water pipe facing each first electrode.
The feature is. Also, the present invention provides a method for inserting a first electrode into a water pipe of a boiler, inserting a second electrode into a lower header of a boiler, connecting the first electrode and the second electrode to a corrosion determiner, and The third feature is that the corrosion state of the boiler can is detected based on the value of the current flowing through the boiler. Further, according to the present invention, the first electrode and the second electrode are inserted into the water portion of the boiler can in a state where they are close to each other, and the first electrode and the second electrode are connected to a corrosion determiner, and the both electrodes are connected. The fourth feature is that the corrosion state of the boiler can is detected based on the value of the flowing current.

Further, according to the present invention, the first electrode and the second electrode are inserted into the water supply pipe in a state of being close to each other, and the first electrode and the second electrode are inserted into the water supply pipe.
A fifth feature is that the electrode and the second electrode are connected to a corrosion determiner, and a corrosion state in the water supply pipe is detected based on a current value flowing between the two electrodes. Further, the present invention has a configuration in which electrodes are inserted into a water supply pipe, these electrodes and the water supply pipe are connected to a corrosion determiner, and a corrosion state in the water supply pipe is detected based on a current value flowing between the two. This is the sixth feature.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In a boiler provided with a can having a structure in which an upper header and a lower header are connected by a plurality of water tubes,
A first electrode is inserted into the water tube, and a second electrode is provided on an outer peripheral portion of the water tube facing the first electrode. The first electrode and the second electrode are connected to a corrosion determiner, and a corrosion state of the water pipe is detected based on a current value flowing between the two electrodes. As the corrosion of the water pipe progresses, a current is generated due to the oxidation reaction of the corrosion, and a current almost proportional to the amount of corrosion flows. By detecting this current value, the corrosion state of the water pipe can be detected. A plurality of the first electrodes may be provided along the axial direction of the water pipe. A second electrode is provided on an outer peripheral portion of the water pipe facing each first electrode, and the first electrode is provided with a corrosive state over a predetermined length in the axial direction of the water pipe. Is detected.

The above-described configuration can be applied to any boiler using a water pipe, in addition to a multi-tube once-through boiler. In a boiler with multiple water tubes,
The first electrode and the second electrode are provided on a water pipe in which corrosion is likely to occur. Corrosion is likely to occur in water pipes with a high heat load, for example, it is composed of two water pipe rows, an inner water pipe row and an outer water pipe row, and the combustion gas generated in the combustion chamber inside the inner water pipe row flows from the opening of the inner water pipe row. A can body (a so-called ω flow can body) having a configuration in which the combustion gas passage formed between the inner water pipe row and the outer water pipe row branches right and left, flows, merges, and then flows out of the opening of the outer water pipe row to the outside. In (2), corrosion is likely to occur in the water pipes of the inner water pipe row near the opening of the inner water pipe row and the opening of the outer water pipe row. Therefore,
These water tubes are provided with the first electrode and the second electrode.

Further, in the present invention, the first pipe is provided in the water pipe.
An electrode is inserted and a second electrode is inserted into the lower header. The first electrode and the second electrode are connected to a corrosion determiner, and a corrosion state of the water pipe is detected based on a current value flowing between the two electrodes. When the corrosion of the water pipe progresses, a current is generated by an oxidation reaction of the corrosion, and a current flows substantially in proportion to the corrosion amount. By detecting this current value, the corrosion state of the water pipe is detected. This configuration can be applied to any boiler having a configuration in which the upper header and the lower header are connected by a plurality of water pipes, in addition to the multi-tube once-through boiler.

Further, in the present invention, the first electrode and the second electrode are inserted into the water portion of the boiler can in a state of being close to each other, and the first electrode and the second electrode are connected to a corrosion determiner. In this configuration, one of the first electrode and the second electrode is set to a material that is relatively susceptible to corrosion (a material that is slightly more susceptible to corrosion than the material of the boiler can), and the corrosion of that electrode is set. The current value generated according to the situation is detected. That is, the state of corrosion of the boiler can is detected based on the value of the current flowing between the two electrodes. The installation position of both electrodes may be anywhere in the water part of the boiler can body, but may be provided in a water pipe in addition to the lower header. This configuration can be applied to a boiler such as a furnace tube boiler, a smoke tube boiler, and a furnace tube boiler, in addition to a water tube boiler (including a multi-tube once-through boiler).

[0010] If the first electrode and the second electrode are inserted into the water supply pipe instead of the boiler can, the corrosion state of the water supply pipe can be detected. That is, the first electrode and the second electrode are inserted into the water supply pipe in a state where they are close to each other, and the first electrode 2 and the second electrode 3 are connected to the corrosion determiner 4. The corrosion state in the water supply pipe is detected based on the value of the current flowing between the two electrodes. This water supply pipe can be applied to a general water supply pipe for supplying water to various devices in addition to a water supply pipe for supplying water to the boiler can body. The water supply pipe also includes a hot water supply pipe for supplying hot water.

[0011] Further, an electrode is inserted into a water supply pipe, the electrode and the water supply pipe are connected to a corrosion determiner, and a corrosion state in the water supply pipe is detected based on a current value flowing between the electrodes. Can also.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram showing a first embodiment of the present invention. The can body is configured by connecting an upper header (not shown) and a lower header 6 with a plurality of water tubes 1. First
The electrode 2 is inserted from the bottom wall of the lower header 6 and inserted into the water pipe 1 through the lower header 6. The tip detecting section of the first electrode 2 is located at a position about one third of the entire length of the water pipe from the lower end of the water pipe 1. The material of the tip detecting portion of the first electrode 2 is brass (C
u-Zn) is used. Other materials may be used as long as they have the same natural potential as brass (for example, SU
S304). An annular second electrode 3 is provided on the outer peripheral portion of the water tube 1 facing the first electrode 2. Various materials can be used as the material of the second electrode 3 as long as it is a conductor.

The first electrode 2 and the second electrode 3 are
It is connected to the corrosion determiner 4 via the current-voltage converter 7. The corrosion state of the water pipe 1 is detected based on the value of the current flowing between the two electrodes. When the corrosion of the water pipe 1 progresses, a current is generated by an oxidizing reaction of the corrosion, and a current almost proportional to the amount of corrosion flows. By detecting this current value, the water pipe 1 is detected.
Can be detected.

An alarm device 8 and a chemical injection device 9 are connected to the corrosion determination device 4. When the corrosion determiner 4 determines that the corrosion has progressed to a stage that requires some treatment, an alarm to that effect is generated by the alarm device 8. At the same time, the control unit controls the injection device 9 to increase the injection amount,
Improve water quality. The determination conditions for controlling the alarm device 8 and the medicine injection device 9 may be set independently of each other.

According to the above configuration, the corrosion state of the water pipe 1 can be detected automatically and continuously, puncture of the can body due to omission of inspection can be reliably prevented, and appropriate measures can be taken in the early stage of corrosion. be able to. In addition, appropriate chemical injection control can be performed to improve the corrosion state. The thinning state of the water pipe 1 can be detected from the value of the current value.

In the second embodiment shown in FIG. 2, a plurality of sets of the first electrode 2 and the second electrode 3 are provided along the axial direction of the water tube 1. An insulating rod member 10 is inserted from the bottom wall of the lower header 6, penetrates through the lower header 6, and is inserted into the water pipe 1. A plurality of first electrodes 2 are provided in the axial direction of the rod member 10, and second electrodes 3 are provided on the outer peripheral portion of the water tube 1 facing each first electrode 2. Each set of the first electrode 2 and the second electrode 3 is connected to the corrosion determiner 4 via the current-voltage converter 7. The corrosion state of the water pipe 1 is detected over a predetermined length in the water pipe axial direction based on the current value flowing between both electrodes of each set. An alarm device 8 and a chemical injection device 9 are connected to the corrosion determination device 4, and an alarm is issued or the amount of chemical injection is increased to improve water quality according to the corrosion state.

In the third embodiment shown in FIG. 3, the first electrode 2 is inserted from the bottom wall of the lower header 6, inserted through the lower header 6 into the water tube 1, and the second electrode 3 is inserted into the lower header 6. And inserted from its side wall. The tip of the first electrode 2 is located at a position about one third of the entire length of the water tube from the lower end of the water tube 1. The material of the first electrode 2 is brass (Cu-Zn), stainless steel (for example, SUS304), or the like. Second
Various materials can be used as the material of the electrode 3 as long as it is a conductor.

The first electrode 2 and the second electrode 3 are connected to a corrosion judging device 4 via a current-voltage converter 7 to detect a current value generated according to the corrosion state of the water pipe 1. First electrode 2
The portion penetrating the inside of the lower header 6 is covered with an insulating member 15 to detect a current value between the portion of the first electrode 2 inserted into the water tube 1 and the second electrode 3. The other configuration is the same as that of the first embodiment, and the description is omitted.

The fourth embodiment shown in FIG. 4 and FIG.
The electrode 2 and the second electrode 3 are inserted into the water portion of the boiler can body, in the illustrated embodiment, into the lower header 6 in a state of being close to each other. As shown in FIG. 5, the first electrode 2 and the second electrode 3
Is formed integrally with a spacer 11 interposed therebetween, the outside thereof is covered with a cover 12, and only the distal end is exposed. The material of the first electrode 2 may be brass (Cu-Zn), or may be another material as long as the material has the same natural potential as brass (for example, SUS304). The material of the second electrode 3 is a material which is relatively easily corroded (a material which is slightly more easily corroded than the material of the boiler can, for example, Z
n) is used. The spacer 11 uses an insulator such as Teflon.

The first electrode 2 and the second electrode 3 are connected to a corrosion judging device 4 via a current-voltage converter 7 to detect a current value generated according to the corrosion state of the electrode. That is, the state of corrosion of the boiler can is detected based on the value of the current flowing between the two electrodes. An alarm device 8 and a chemical injection device 9 are connected to the corrosion determination device 4, and an alarm is issued or the amount of chemical injection is increased to improve water quality according to the corrosion state.

In the fifth embodiment shown in FIG. 6, the first electrode 2 and the second electrode 3 are inserted into the water supply pipe 5 in a state of being close to each other.
The first electrode 2 and the second electrode 3 are connected to a corrosion determiner 4 via a current-voltage converter 7. The corrosion state in the water supply pipe 5 is automatically and continuously detected based on the value of the current flowing between the two electrodes. First electrode 2 and second electrode 3
Is similar to that shown in FIG.
In the illustrated embodiment, the water supply pipe 5 is connected to the main pipe 1.
3, a bypass pipe 14 is connected to
The first electrode 2 and the second electrode 3 are inserted into the bypass pipe 14. Although the first electrode 2 and the second electrode 3 may be inserted directly into the main pipe 13 for direct measurement, the measurement using the bypass pipe 14 allows the measurement to be performed in a state where the flow rate of water is reduced. Life can be extended. An alarm device 8 and a chemical injection device 9 are connected to the corrosion determination device 4, and an alarm is issued or the amount of chemical injection is increased to improve water quality according to the corrosion state.

In the sixth embodiment shown in FIG. 7, the electrode 16 is inserted into the water supply pipe 5, and the electrode 16 and the water supply pipe 5 are inserted.
Is connected to the corrosion determiner 4 via the current-voltage converter 7. The corrosion state in the water supply pipe 5 is automatically and continuously detected based on the value of the current flowing between the electrode 16 and the water supply pipe 5. As in the fifth embodiment, the water supply pipe 5 has a configuration in which a bypass pipe 14 is connected to a main pipe 13, and an electrode 16 is inserted into the bypass pipe 14. In the bypass pipe 14, the current value is measured in a state where the flow rate of water is reduced, so that the life of the electrode 16 is extended. As a material of the electrode 16, brass (Cu-Zn), a stainless steel material (for example, SUS304), or the like is used. On the other hand, as a material of the bypass pipe 14, a zinc alloy is used. Conversely, a configuration in which a stainless steel material (for example, SUS304) is used as the material of the bypass pipe 14 and the tip of the electrode 16 is coated with a zinc alloy can also be adopted.
An alarm device 8 and a chemical injection device 9 are connected to the corrosion determination device 4, and an alarm is issued or the chemical injection amount is increased to improve the water quality according to the corrosion state.

[0024]

As described above, according to the present invention, it is possible to automatically and continuously detect the corrosion state of a boiler can or a water supply pipe. It is reliably prevented and appropriate measures can be taken in the early stages of corrosion. Further, it is also possible to detect the thinning state of the boiler can or the water supply pipe from the current value.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a first embodiment of the present invention.

FIG. 2 is an explanatory view showing a second embodiment of the present invention.

FIG. 3 is an explanatory view showing a third embodiment of the present invention.

FIG. 4 is an explanatory view showing a fourth embodiment of the present invention.

FIG. 5 is an enlarged front view showing a configuration of an electrode in the embodiment of FIG.

FIG. 6 is an explanatory view showing a fifth embodiment of the present invention.

FIG. 7 is an explanatory view showing a sixth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water pipe 2 1st electrode 3 2nd electrode 4 Corrosion judging device 5 Water supply pipe 6 Lower header 16 Electrode

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideo Furukawa 7th Horie-cho, Matsuyama-shi, Ehime Prefecture, Miura Research Institute (72) Inventor Yuji 7 Horie-cho, Matsuyama-shi, Ehime Prefecture, Miura Research Institute

Claims (6)

[Claims] 1. A first electrode 2 is inserted into a water tube 1 of a boiler, and a second electrode 3 is provided on an outer peripheral portion of the water tube 1 facing the first electrode 2, and the first electrode 2 and the second electrode 2 are provided. 3. A corrosion detector for a boiler can body, wherein 3 is connected to a corrosion determiner 4 to detect the corrosion state of the water pipe 1 based on a current value flowing between both electrodes. 2. The apparatus for detecting corrosion in a boiler can body according to claim 1, wherein a plurality of first electrodes 2 are provided along an axial direction of the water pipe 1, and the water pipes 1 facing each first electrode 2 are provided. A corrosion detecting device for a boiler can body, wherein a second electrode 3 is provided on an outer peripheral portion of the boiler can. 3. A first electrode 2 is inserted into a water pipe 1 of a boiler, a second electrode 3 is inserted into a lower header 6 of the boiler, and the first electrode 2 and the second electrode 3 are connected to a corrosion determiner 4. A corrosion detecting device for a boiler can, wherein the corrosion detecting device is configured to detect a corrosion state of the boiler can based on a current value flowing between both electrodes. 4. A first electrode 2 and a second electrode 3 are inserted into a water portion of a boiler can in a state of being close to each other, and the first electrode 2 and the second electrode 3 are connected to a corrosion determiner 4. A corrosion detection device for a boiler can, wherein the corrosion state of the boiler can is detected based on a current value flowing between both electrodes. 5. A first electrode 2 and a second electrode 3 are inserted into a water supply pipe 5 in a state of being close to each other, and the first electrode 2 and the second electrode 3 are connected to a corrosion judging device 4. A corrosion detecting device for a water supply pipe, wherein a corrosion state in the water supply pipe 5 is detected based on a current value flowing between the two. 6. An electrode 15 is inserted into the water supply pipe 5, the electrode 15 and the water supply pipe 5 are connected to the corrosion determiner 4, and the state of corrosion in the water supply pipe 5 is determined based on the value of the current flowing between them. An apparatus for detecting corrosion in a water supply pipe, wherein the apparatus is configured to detect the corrosion.