JP2013152058A - Evaluation method and device for soundness of fire-resisting material support stud - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaluation method and device for soundness of a fire-resisting material support stud, which can detect abnormalities such as a junction fault between a furnace wall surface and a stud in an early stage and can evaluate the soundness of the stud correctly.SOLUTION: An evaluation method for soundness of a fire-resisting material support studs 5 which support a plurality of fire-resisting materials 6 attached to a furnace wall surface 1 by welding or driving one side end to the furnace wall surface 1 which is arranged under high temperature and corrosive atmosphere and has conductivity, and enforced on the surface wall surface 1, includes: a terminal connection step in which a first terminal 12 and a second terminal 14 of a low resistance meter 11 are made to abut on respective parts from which the other ends of the two spaced studs 5 are exposed from the fire-resisting material 6; a measurement step which measures a resistance value between the first terminal 12 and the second terminal 14 by using the low resistance meter 11; and an evaluation step which evaluates a contact state between the furnace wall surface 1 and the stud 5 based on the resistance value measured at the measurement step.

Description

  The present invention relates to a soundness evaluation method and apparatus for a refractory material supporting stud that supports a refractory material constructed on a furnace wall surface.

  In general, in a boiler, an incinerator, or the like, a refractory material is applied to the furnace wall for the purpose of protecting the furnace wall from a high temperature and corrosive atmosphere. For example, when installing refractory material on a water-cooled wall, weld or drive multiple bolt-shaped studs perpendicular to the water-cooled wall, construct an irregular refractory material between the studs, and support the refractory material by the stud Such a furnace wall structure is known.

In such a furnace wall structure, the stud is buried in refractory material, since numerous pores in the refractory material is present, reaching the stud acidic gas such as SO _x and HCl in the combustion exhaust gas passes through the pores And may accelerate the corrosion of the stud. In particular, when the stud is attached to the water-cooled wall, condensation is likely to occur at the stud base near the cooling water, which promotes the progress of corrosion. Furthermore, stress corrosion cracking is likely to occur because the load of the refractory material is concentrated on the stud base. Thus, if the stud base is thinned or cracked due to corrosion, the stud will come off the furnace wall. If many of these studs occur, the refractory material may fall off. In order to prevent this, it is necessary to detect and repair the abnormality of the stud at an early stage.

However, since the thinning and cracking of the stud is a phenomenon that occurs inside the furnace wall, there is a problem that discovery cannot be confirmed by visual observation and discovery is delayed.
Therefore, hitting inspection methods, ultrasonic flaw detection methods, and the like have been widely known as non-destructive techniques for inspecting internal defects. Here, the hammering inspection method is a method in which the surface of an inspection object is hit with a hammer and the internal state is grasped by the generated sound. As described in, for example, Patent Document 1 and the like, the ultrasonic flaw detection inspection method allows ultrasonic waves to enter an inspection object such as a refractory or a concrete structure, and analyzes the received reflected waves to remove internal defects and the like. To detect.

  As a related technique, Patent Document 2 discloses a method for nondestructively inspecting a fixed refractory using thermography. This method heats a regular refractory, images its temperature distribution by thermography, and inspects physical properties such as internal defects of the refractory and fine defects on the surface based on the imaged temperature distribution. .

JP 2001-289827 A Japanese Patent Laid-Open No. 11-51887

  However, since the hammering inspection method cannot obtain a quantitative inspection result, a skilled technique and experience are required from the inspector, and the inspection result may vary depending on the inspector. Also, detection was impossible at the initial stage where the studs were removed from the furnace wall. In the ultrasonic flaw detection inspection method described in Patent Literature 1, detection is possible when a space is generated inside the refractory material, but the stud is detached from the furnace wall surface as in the sound percussion inspection method. Until then, it could not be detected. In the inspection using the thermography described in Patent Document 2, it is considered that it is possible to detect the soundness of the stud to some extent because the heat becomes difficult to be transmitted if the contact between the stud and the furnace wall surface becomes poor. There was a problem that detection accuracy was low because of evaluation.

  The present invention has been made in view of the above-described circumstances, and it is possible to detect abnormalities such as poor bonding between a furnace wall surface and a stud at an early stage, and it is possible to accurately evaluate the soundness of the stud. It aims at providing the soundness evaluation method and apparatus of a stud for material support.

  The method for evaluating the soundness of a refractory material supporting stud according to the present invention includes a furnace that is disposed in a high temperature and corrosive atmosphere, and one end of the furnace is welded or driven into an electrically conductive furnace wall surface. A method for evaluating the soundness of a refractory material supporting stud attached to a wall surface and supporting a refractory material constructed on the furnace wall surface, wherein the other end portions of the two spaced studs are separated from the refractory material. A terminal connecting step of bringing the first terminal and the second terminal of the ohm meter into contact with each exposed part; a measuring step of measuring a resistance value between the first terminal and the second terminal by the ohm meter; And an evaluation step for evaluating a contact state between the furnace wall surface and the stud based on the resistance value measured in the measurement step.

  Usually, the stud is made of a conductive metal material, and the furnace wall surface is conductive. Therefore, a path through which a current flows is formed by two spaced studs and the furnace wall surface between them. . The main part which becomes resistance on this path is the connection part between the stud and the furnace wall surface. When the soundness of the stud is maintained, that is, when the stud is properly attached to the furnace wall surface, the resistance of the connection portion is substantially constant. On the other hand, if the stud is thinned or cracked, or if at least part of the connection of the stud to the furnace wall is removed, the contact area between the stud and the furnace wall is less than normal. It becomes smaller and the resistance of the connection part increases.

  As described above, the contact state between the stud and the furnace wall surface clearly appears in the resistance value between the two studs. Therefore, in the present invention, the resistance value is measured by measuring the resistance value between the two spaced studs. It is possible to accurately evaluate the soundness of the stud based on the above. For example, if the measured resistance value is larger than the resistance value assumed at the time of soundness, it is evaluated that the soundness of the stud is impaired, such as a poor connection between the stud and the furnace wall surface. it can. Therefore, abnormalities such as poor bonding between the furnace wall and the stud, which could not be detected by conventional nondestructive inspection methods, can be detected at the initial stage, and repair can be performed before the refractory material falls off. Become.

  In the soundness evaluation method, in the terminal connection step, the first terminal is brought into contact with a reference stud selected from the plurality of studs, and the second terminal is set to one stud different from the reference stud. After the contact, the second terminal is brought into contact with the other stud in a state where the first terminal is brought into contact with the reference stud, and the resistance value of the plurality of studs is repeated by repeating this. May be measured sequentially.

  Thus, even if a large number of studs must be inspected by maintaining the first terminal in contact with the reference stud and moving only the second terminal between different studs, the efficiency Inspection can be performed well and the inspection time can be shortened. In addition, it is preferable to select a healthy stud from among a plurality of studs measured in advance.

  Alternatively, in the soundness evaluation method, the plurality of studs are attached to the furnace wall surface at equal intervals, and the terminal connection step corresponds to the distance between the two studs. After the first terminal and the second terminal are simultaneously brought into contact with the two studs by a terminal unit that is mounted on a jig with the first terminal and the second terminal separated from each other, the terminal unit is moved. The resistance values of the plurality of studs may be sequentially measured by bringing the first terminal and the second terminal into contact with the two studs in another combination at the same time and repeating this operation. .

  As described above, by using the terminal unit in which the distance between the first terminal and the second terminal is fixed corresponding to the distance between the studs, the contact work of the first terminal and the second terminal to the stud is efficiently performed. Even when a large number of studs must be inspected, the inspection time can be shortened.

In the soundness evaluation method, the first terminal and the second terminal are configured by at least two terminals for voltage measurement and current measurement, respectively, and the resistance is measured using a four-terminal method in the measurement step. It is preferable to measure the value.
As described above, by measuring the resistance value using the four-terminal method, the resistance value can be measured with high accuracy even when the resistance value between the two studs is small.

In the soundness evaluation method, a correlation between the resistance value and the contact ratio when the contact ratio between the stud and the furnace wall surface is varied is acquired in advance, and the correlation includes the correlation in the evaluation step. Preferably, the contact rate is obtained from the resistance value based on the resistance value, and the contact state is evaluated based on the contact rate.
The contact rate here is a value indicating the contact state between the stud and the furnace wall surface. Therefore, based on the correlation between the resistance value and the contact rate acquired in advance, the contact rate is obtained from the resistance value measured by the ohmmeter, and the contact state is evaluated based on the contact rate. Can be obtained.

  In this case, the threshold value of the resistance value is set based on the correlation between the resistance value and the contact rate, and the furnace wall surface is divided into a region including a predetermined number of the studs, and the evaluation step Then, the resistance value measured in the measurement step is compared with the threshold value, and the number of studs where the resistance value exceeds the threshold value is greater than a preset number, or the resistance value exceeds the threshold value. When the ratio of the exceeding number of studs to the number of studs in the region is larger than a preset set ratio, it may be evaluated that the refractory material may be dropped.

In general, when the soundness of the stud is impaired, it is greatly affected by the surrounding environment, and therefore, the same abnormal phenomenon occurs in the stud in a certain area range. If a large number of studs supporting the refractory material in a predetermined region are detached, the worst case of dropping off the refractory material is caused.
On the other hand, when the resistance value measured by the resistance meter exceeds the threshold value, it can be determined that the soundness of the stud is impaired. However, since the refractory material is supported by multiple studs, even if some of the studs are removed, the refractory material is supported by many other studs and may not be related to the fallout of the refractory material. . If the refractory material and the stud are repaired at this stage, the maintenance cost increases. Therefore, it is possible to accurately grasp the repair time by evaluating the possibility of refractory material dropping out based on the number of studs whose resistance value exceeds the threshold or the ratio of the number of studs to the number of studs in the area. It becomes.

  The refractory material supporting stud soundness evaluation apparatus according to the present invention is disposed in a high temperature and corrosive atmosphere, and one end of the furnace is welded or driven into an electrically conductive furnace wall surface. A device for evaluating the health of a refractory material supporting stud attached to a wall surface and supporting a refractory material constructed on the furnace wall surface, wherein the other end portions of the two spaced studs are separated from the refractory material. A resistance measurement unit that measures a resistance value between the first terminal and the second terminal by bringing the first terminal and the second terminal into contact with each exposed part, and the resistance measured by the resistance measurement unit A storage unit for storing a value, and an evaluation unit for evaluating a contact state between the furnace wall surface and the stud based on the resistance value stored in the storage unit.

  According to the present invention, by measuring the resistance value between two spaced apart studs, it is possible to accurately evaluate the soundness of the stud based on this resistance value. Therefore, abnormalities such as poor bonding between the furnace wall and the stud, which could not be detected by conventional nondestructive inspection methods, can be detected at the initial stage, and repair can be performed before the refractory material falls off. Become.

  In the soundness evaluation apparatus, the resistance measurement unit includes the first terminal and the plurality of studs corresponding to a distance between the two studs among the plurality of studs attached to the furnace wall surface at equal intervals. It is preferable to have a terminal unit in which the second terminal is separated and attached to the jig.

  According to this terminal unit, since the distance between the first terminal and the second terminal is fixed corresponding to the distance between the studs, the contact work of the first terminal and the second terminal to the stud can be efficiently performed. Even when a large number of studs must be inspected, the inspection time can be shortened.

In the soundness evaluation apparatus, the first terminal and the second terminal are configured by at least two terminals for voltage measurement and current measurement, respectively, and the resistance measurement unit uses a four-terminal method. The resistance value may be measured.
As described above, by measuring the resistance value using the four-terminal method, the resistance value can be measured with high accuracy even when the resistance value between the two studs is small.

In this case, at least the tip of the voltage measuring terminal of the first terminal and the second terminal may be formed into a rotatable drill shape.
As a result, even if foreign matter such as oxide scale adheres to the stud surface, the stud can be exposed by turning the tip of the drill-like terminal to scrape off the foreign matter, and the resistance value can be measured smoothly. It becomes possible to do. Moreover, since other tools, such as a grinder, are not required, work can be simplified.

In the soundness evaluation apparatus, a correlation between the resistance value and the contact rate when the contact rate between the stud and the furnace wall surface is changed is acquired in advance, and the resistance value is stored in the storage unit. And the contact rate is stored, and the evaluation unit obtains the contact rate from the resistance value based on the correlation and evaluates the contact state based on the contact rate. Is preferred.
Thus, an appropriate evaluation result can be obtained by obtaining the contact rate from the resistance value based on the correlation between the resistance value and the contact rate acquired in advance, and evaluating the contact state based on the contact rate. .

  In the present invention, by measuring the resistance value between two spaced studs, the soundness of the stud can be accurately evaluated based on the resistance value. Therefore, abnormalities such as poor bonding between the furnace wall and the stud, which could not be detected by conventional nondestructive inspection methods, can be detected at the initial stage, and repair can be performed before the refractory material falls off. Become.

It is a perspective view which shows the water cooling wall which is an example of the furnace wall to which embodiment of this invention is applied. It is a figure which shows the whole structure of the soundness evaluation apparatus which concerns on 1st Embodiment. It is a table | surface which shows correlation with a resistance value and a contact rate. It is a graph which shows correlation with a resistance value and a contact rate. It is a figure which shows the example of a display on a display part. It is a flowchart which shows the soundness evaluation method which concerns on 1st Embodiment. It is a figure which shows the whole structure of the soundness evaluation apparatus which concerns on 2nd Embodiment. It is a figure explaining the calculation method of resistance value in a 2nd embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, and are merely illustrative examples. Only.

[First Embodiment]
FIG. 1 is a perspective view showing a water-cooled wall as an example of a furnace wall to which an embodiment of the present invention is applied.
As shown in the figure, the water cooling wall 1 is disposed at a high temperature and in a corrosive atmosphere like a boiler or an incinerator. The water cooling wall 1 has a plurality of water pipes 2 arranged in parallel at predetermined intervals, and fins 3 are provided between adjacent water pipes 2. At this time, the fin 3 is arrange | positioned so that a plane may be formed along the tangential direction of the some water pipe 2 so that the installation conditions of the stud 5 mentioned later can be made the same between the some studs 5. FIG. It is preferable. Of the water-cooled walls 1, at least the water-cooled walls to which the studs 5 are attached, that is, the fins 3 are formed of a conductive material. The material is stainless steel, carbon steel or the like.

A stud 5 is attached to the surface 1a of the water-cooled wall 1 so as to be substantially perpendicular to the water-cooled wall surface 1a. A plurality of studs 5 are attached at regular intervals, and are arranged in a grid pattern, for example. The stud 5 is formed of a bolt-shaped or pin-shaped metal. As the material, a conductive metal such as iron, stainless steel, carbon steel or the like is used.
A refractory material 6 is embedded between the plurality of studs 5, and the refractory material 6 is supported on the water-cooled wall surface 1 a by the plurality of studs 5. This refractory material 6 is provided for the purpose of protecting the water-cooled wall 1 from a high-temperature atmosphere in the furnace and a corrosive atmosphere such as acid gas. The refractory material 6 may be an irregular refractory material or a regular refractory material. The stud 5 also plays a role of heat transfer, and transfers the combustion heat in the furnace to the cooling water. One end of the stud 5 is welded or driven into the water-cooled wall 1a, and the other end is exposed from the refractory material 6 into the furnace.

  With reference to FIG. 2, the structure of the soundness evaluation apparatus which concerns on 1st Embodiment of this invention is demonstrated. As shown in the figure, the refractory material supporting stud soundness evaluation apparatus 10 is a low-cost device in which a first probe (first terminal) 12 and a second probe (second terminal) 14 are connected by lead wires 13 and 15. An ohmmeter 11 and a processing means 20 having a storage unit 21, an evaluation unit 22 and a display unit 23 are provided. In addition, although the figure shows the case where the low resistance meter 11 and the processing means 20 are provided separately, these may be provided integrally.

  The low resistance meter 11 is configured such that the first probe 12 and the second probe 14 are brought into contact with the exposed portions of the two studs 5 that are separated from each other, and the other stud 5 passes from one stud 5 through the water cooling wall 1. Measure the resistance value of the electrical path formed in The resistance of the stud 5, the resistance of the contact portion 7, and the resistance of the water cooling wall 1 exist on this path. The sum of these resistances becomes the resistance of the entire path. In addition, it is preferable that the low resistance meter 11 is an apparatus which measures resistance value using a 4-terminal method. As described above, by measuring the resistance value using the four-terminal method, the resistance value can be measured with high accuracy even when the resistance value between the two studs 5 is small. In this case, the first probe 12 and the second probe 14 are each composed of at least two terminals for voltage measurement and current measurement. In this embodiment, the low resistance meter 11 that can measure low resistance satisfactorily is exemplified as the resistance meter, but this resistance meter measures the resistance value between the two studs 5 in an appropriate range. It may be a measuring instrument that can be used, and may be a general resistance meter, or may be a so-called digital multimeter or digital voltmeter.

  Further, at least the tip of the voltage measurement terminal of the first probe 12 and the second probe 14 may be formed into a rotatable drill shape. As a result, even if foreign matter such as oxide scale adheres to the surface of the stud 5, the stud 5 can be exposed by rotating the tip of the drill-like probe to scrape off the foreign matter, and the resistance value can be smoothly increased. Can be measured. Further, since no other equipment such as a grinder is required, the operation can be simplified. In the case where a probe having such a structure is not used, and the foreign matter such as oxide scale adheres to the stud 5 or is buried in the refractory material 6, the surface of the stud 5 is inspected by a grinder before inspection. May be exposed.

  As an example of a resistance value measuring method using the low resistance meter 11, first, the first probe 12 is brought into contact with the reference stud 5a selected from the plurality of studs 5, and the second probe 14 is referred to as the reference stud 5a. A resistance value is measured by contacting a different stud 5. Next, the second probe 14 is brought into contact with another stud in a state where the first probe 12 is brought into contact with the reference stud 5a. By repeating this, the resistance values of several studs 5 may be measured sequentially.

  In this way, when the first probe 12 is kept in contact with the reference stud 5a and only the second probe 14 is moved between the different studs 5, a large number of studs 5 must be inspected. Even if it exists, it can test | inspect efficiently and can shorten inspection time. As the reference stud 5a, it is preferable to select a healthy stud from among a plurality of studs 5 previously measured. However, when the soundness of the reference stud 5a is not clear, the reference stud 5a may not be sound if a high resistance value is detected regardless of which stud 5 the second probe 14 contacts. Therefore, another reference stud 5a may be selected again.

The resistance value measured by the low resistance meter 11 is input to the processing means 20.
The processing means 20 performs a predetermined calculation on the data such as the resistance value input from the low resistance meter 11 by the calculation part such as the evaluation unit 22, stores the data in the storage unit 21, and the display unit 23. To display data. The part responsible for the calculation function is composed of, for example, a CPU (Central Processing Unit) (not shown), a RAM (Random Access Memory), a computer-readable recording medium, and the like, and mainly performs the calculation of the evaluation unit 22. A series of processing steps for realizing the calculation of the evaluation unit 22 is recorded in a recording medium or the like in the form of a program, and the CPU reads the program into a RAM or the like to execute information processing / calculation processing. Thus, the calculation is realized.

More specifically, the resistance value between the studs 5 measured by the low resistance meter 11 is accumulated in the storage unit 21. This may be stored in the storage unit 21 at any time when measured by the low resistance meter 11, or a plurality of resistance values accumulated in the storage unit (not shown) of the low resistance meter 11 are periodically sucked and accumulated. May be.
The evaluation unit 22 evaluates the contact state between the water-cooled wall 1 and the stud 5, that is, the soundness of the stud, based on the resistance value accumulated in the storage unit 21. When the integrity of the stud 5 is maintained, that is, when the stud 5 is appropriately attached to the water-cooled wall 1, the path resistance between the two studs 5 is substantially constant. However, when the stud 5 is thinned or cracked, or when at least a part of the contact portion 7 of the stud 5 to the water-cooled wall 1 is removed, the contact area between the stud 5 and the water-cooled wall 1 is sound. It becomes smaller than the time, and the resistance of the contact portion 7 increases. You may evaluate the soundness of the stud 1 using such a principle.

  In addition, the evaluation unit 22 acquires in advance a correlation between the resistance value and the contact ratio when the contact ratio between the stud 5 and the water cooling wall 1 is varied, and based on this correlation, the low resistance meter 11. It is preferable to obtain a contact rate from the resistance value measured in step 1 and evaluate the contact state between the stud 5 and the water cooling wall 1 based on the contact rate. Here, the contact rate is a value indicating the contact state between the stud 5 and the water-cooled wall 1.

The correlation between the resistance value and the contact rate can be obtained by performing the following test.
In this test, the resistance values were measured for the contact ratios of the stud 5 and the water cooling wall 1 of 0% (complete peeling), 20%, 50%, and 100% (complete contact). At this time, as shown in FIG. 2, the resistance values of _four studs 5 (L _{1 to} L ₄ ) having different distances from the reference stud 5a were measured for each contact rate.

The measurement results are shown in FIGS. FIG. 3 is a table showing the correlation between the resistance value and the contact rate, and FIG. 4 is a graph showing the correlation between the resistance value and the contact rate. As shown in these figures, the higher the contact ratio, the larger the resistance value with respect to the distance, and the difference in the contact ratio could be clearly confirmed. In this example, since the contact rate is 100% and 0.18Ω, it can be seen that the contact state between the stud 5 and the water-cooled wall 1 changes when the value is larger than this. That is, it can be evaluated that the soundness is impaired.
As described above, based on the correlation between the resistance value and the contact rate acquired in advance, the contact rate is obtained from the resistance value measured by the low resistance meter, and the contact state is evaluated based on the contact rate. Evaluation results can be obtained. The correlation may be stored in the storage unit 21.

  Furthermore, a threshold value of the resistance value may be set based on the correlation between the resistance value and the contact rate. This threshold value may be stored in the storage unit 21 together with the correlation. Then, the evaluation unit 22 compares the resistance value measured by the low resistance meter 11 with a threshold value, and evaluates that the soundness of the stud 1 is impaired when the resistance value exceeds the threshold value.

  Furthermore, the water-cooled wall surface 1a is divided into a region including a predetermined number of studs 5, and the number of studs whose resistance value measured by the low resistance meter 11 exceeds the threshold is preset in this region. When the number of studs exceeds the set number, or when the ratio of the number of studs whose resistance value exceeds the threshold to the number of studs in the area is larger than a preset set ratio, it is evaluated that the fireproof material 6 may be dropped. May be.

In general, when the soundness of the stud 5 is impaired, it is greatly affected by the surrounding environment, so that the same abnormal phenomenon occurs in the stud 5 in a certain area range. If a large number of studs 5 supporting the refractory material 6 in a predetermined region are removed, the worst case of dropping off the refractory material 6 is caused.
On the other hand, when the resistance value measured by the low resistance meter 11 exceeds the threshold value, it can be determined that the soundness of the stud 5 is impaired. However, since the refractory material 6 is supported by a plurality of studs 5, even if some of the studs 5 are removed, the refractory material 6 is supported by many other studs 5, and the refractory material 6 is dropped off. May be irrelevant. If the refractory material 6 and the stud 5 are repaired at this stage, the maintenance cost increases. Therefore, it is possible to accurately grasp the repair time by evaluating the possibility of the refractory material 6 falling off based on the number of studs 5 whose resistance value exceeds the threshold or the ratio of the number of studs to the number of studs in the region. Is possible.

  The display unit 23 displays the evaluation result in the evaluation unit 3 described above. The evaluation result may be displayed as characters or symbols, or may be displayed as a diagram. FIG. 5 is a diagram showing a display example on the display unit. As shown in the figure, the position of the stud 5 with respect to the water-cooled wall surface 1a is displayed as a graphic, and the stud 5 that is not sound enough from the evaluation result and the stud 5 that is kept sound by color or symbol. They may be displayed separately. In this case, the X-direction coordinate and the Y-direction coordinate are set in advance for the water-cooled wall surface 1a, and the measured resistance value and the position coordinate of the stud 5 are associated with each other at the time of measurement by the low resistance meter 11. It is necessary to accumulate

Here, the soundness evaluation method according to the first embodiment will be described with reference to FIG.
First, in step S1, the end portion of the stud 5 in the region to be inspected is polished by a grinder or the like, and a part of the stud 5 is exposed. If the stud 5 is already exposed before polishing, this step may be omitted. Next, in step S2, the first probe 12 is brought into contact with the reference stud 5a, and the second probe 14 is brought into contact with the probe 5 separated from the reference stud 5a. Further, in step S 3, the resistance value between the first probe 12 and the second probe 14 is measured by the low resistance meter 11.

  In step S4, the contact state between the water cooling wall 1 and the stud 5 is evaluated based on the resistance value measured in step S3. At this time, when the resistance value is larger than a preset threshold value, it is evaluated that the soundness of the stud 5 is impaired. In step S5, the second probe 14 is moved and brought into contact with the other stud 5 while keeping the first probe 12 in contact, and the resistance value is measured by returning to step S3. These steps are repeated, and the process ends when the resistance value of the stud 5 within the inspection range is measured.

  As described above, in the present embodiment, by measuring the resistance value between two spaced apart studs 5, it is possible to accurately evaluate the soundness of the stud 5 based on the resistance value. Therefore, abnormalities such as poor bonding between the furnace wall and the stud 5 that could not be detected by the conventional nondestructive inspection method can be detected at the initial stage, and repair can be performed before the refractory material falls off. It becomes.

[Second Embodiment]
Next, a soundness evaluation apparatus and method according to the second embodiment will be described. In the present embodiment, the configuration is the same as that of the first embodiment described above except for the configuration of the probe and the resistance value measuring method. Therefore, here, the same reference numerals are given to members common to the first embodiment, and the description thereof is omitted, and the description will focus on parts different from the first embodiment.

FIG. 7 is a diagram illustrating an overall configuration of the soundness evaluation apparatus according to the second embodiment, and FIG. 8 is a diagram illustrating a resistance value calculation method according to the second embodiment.
In FIG. 7, the low resistance meter 11 has a terminal unit 30 that is attached to a jig 33 with the first probe 31 and the second probe 32 spaced apart from each other in accordance with the distance between the two studs 5. Preferably, in the terminal unit 30, the distance between the first probe 31 and the second probe 32 corresponds to the distance between two adjacent studs 5. According to this terminal unit 30, the distance between the first probe 31 and the second probe 32 is fixed corresponding to the distance between the two studs 5. The contact operation to the stud 5 can be performed efficiently, and even when a large number of studs 5 must be inspected, the inspection time can be shortened. However, this terminal unit 30 is applied when a plurality of studs 5 are attached to the water cooling wall 1 at equal intervals.

  With reference to FIG. 8, an example of the soundness evaluation method using the terminal unit 30 having the above configuration will be described. In the figure, for the sake of simplicity of explanation, the leftmost stud is designated as the first stud, and numbers are assigned to the respective studs from the second stud to the seventh stud in order toward the right side. First, as shown in FIG. 8A, the first probe 31 and the second probe 32 of the terminal unit 30 are brought into contact with the first stud and the second stud, respectively, and a resistance value R (1- 2) is measured. Subsequently, the terminal unit 30 is moved by one stud, and the first probe 31 and the second probe 32 are brought into contact with the second stud and the third stud, respectively, and the resistance value R (2-3) between the studs. Measure. Next, the terminal unit 30 is further moved by one stud, the first probe 31 and the second probe 32 are brought into contact with the third stud and the fourth stud, respectively, and the resistance value R (3-4) between the studs 5 is reached. ). Thus, the terminal unit 30 is moved by one stud at a time, and all the resistance values of the studs 5 in the target area are measured.

In the present embodiment, since the reference stud 5a is not set as in the first embodiment described above, when the measurement is performed between the two studs 5, a resistance value in which two contact states are mixed appears. Therefore, the results obtained by shifting the studs one by one as described above are calculated to calculate the resistance value of each stud, and the soundness of the stud 5 is evaluated based on the resistance value. Also good. In this case, as shown in FIG. 8D, the resistance between the two studs 5 is the resistance Rs of the stud 5, the resistance r1 of the contact portion 7, and the resistance Rb of the water cooling wall 1. Therefore, the resistance value for each stud 5 can be obtained by calculating the following equivalent circuit equation (1).
[Equation 1]

  In the present embodiment, when the soundness of the stud 5 is evaluated, it is not always necessary to calculate the resistance value for each stud 5. As another method, for example, the resistance value of each stud 5 is measured twice by the terminal unit 30. Therefore, the sum of the resistance values for two times may be recorded, and the soundness of the stud 5 may be evaluated based on the sum of the resistance values.

As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to this, In the range which does not deviate from the summary of this invention, you may combine the above-mentioned 1st Embodiment and 2nd Embodiment suitably. However, it goes without saying that various improvements and modifications may be made.
In addition, although this embodiment demonstrated the case where the soundness of the stud 5 welded or struck to the planar water-cooled wall surface 1a was evaluated, the soundness of the stud 5 contacted with the water-cooled wall surface which has a curvature is evaluated. You can also. Moreover, although the soundness evaluation of the stud 5 which contacted the water pipe can also be performed, it is good to measure the resistance value between the two studs 5 which exist in the axial direction of a water pipe in this case.

DESCRIPTION OF SYMBOLS 1 Water cooling wall 1a Water cooling wall 2 Water pipe 3 Fin 5 Stud 5a Reference stud 6 Refractory material 10 Soundness evaluation apparatus 11 Low resistance meter 12 1st probe 13 2nd probe 20 Processing means 21 Memory | storage part 22 Evaluation part 23 Display part 30 Terminal unit 31 First probe 32 Second probe

Claims (11)

A refractory material that is disposed in a high temperature and corrosive atmosphere, and is attached to the furnace wall surface by welding or driving one end to the furnace wall surface having conductivity, and is applied to the furnace wall surface. A method for evaluating the soundness of a refractory material supporting stud that supports
A terminal connection step of bringing the first terminal and the second terminal of the ohmmeter into contact with the respective parts where the other end portions of the two spaced studs are exposed from the refractory material;
A measuring step of measuring a resistance value between the first terminal and the second terminal by the resistance meter;
An evaluation step for evaluating a contact state between the furnace wall surface and the stud based on the resistance value measured in the measurement step, comprising: a refractory material supporting stud soundness evaluation method.   In the terminal connecting step, the first terminal is brought into contact with a reference stud selected from the plurality of studs, and the second terminal is brought into contact with one stud different from the reference stud, The second terminal is brought into contact with the other stud while the first terminal is in contact with the reference stud, and the resistance values of the plurality of studs are sequentially measured by repeating this. The method for evaluating the soundness of a refractory material supporting stud according to claim 1. When the plurality of studs are attached to the furnace wall surface at equal intervals,
In the terminal connecting step, the first stud and the second terminal are spaced apart from each other according to the distance between the two studs, and the first stud is simultaneously attached to the two studs by a terminal unit attached to a jig. After contacting the terminal and the second terminal, the terminal unit is moved so that the first terminal and the second terminal are simultaneously brought into contact with the two studs in another combination, and this is repeated. 2. The method for evaluating the soundness of a refractory material supporting stud according to claim 1, wherein the resistance values of the plurality of studs are sequentially measured.   The first terminal and the second terminal are configured by at least two terminals for voltage measurement and current measurement, respectively, and the resistance value is measured using a four-terminal method in the measurement step. The soundness evaluation method for the refractory material supporting stud according to any one of claims 1 to 3.   A correlation between the resistance value and the contact ratio when the contact ratio between the stud and the furnace wall surface is varied is acquired in advance, and in the evaluation step, the resistance value is calculated from the resistance value based on the correlation. The method for evaluating the soundness of a refractory material supporting stud according to any one of claims 1 to 4, wherein a contact rate is obtained and the contact state is evaluated based on the contact rate. While setting a threshold value of the resistance value based on the correlation between the resistance value and the contact ratio, the furnace wall surface is divided into regions including a predetermined number of the studs,
In the evaluation step, the resistance value measured in the measurement step is compared with the threshold value, and the number of studs where the resistance value exceeds the threshold value is greater than a preset number, or the resistance value is The fire resistance according to claim 5, wherein when the ratio of the number of studs exceeding the threshold to the number of studs in the region is larger than a preset set ratio, it is evaluated that the fireproof material may be dropped. Method for evaluating the soundness of studs for material support. Placed in a high temperature and corrosive atmosphere, one side end is in contact with the electrically conductive furnace wall surface to attach a plurality to the furnace wall surface and support the refractory material constructed on the furnace wall surface A device for evaluating the integrity of a stud for supporting a refractory material,
The first terminal and the second terminal are brought into contact with the portions where the other end portions of the two spaced studs are exposed from the refractory material, respectively, and the resistance value between the first terminal and the second terminal is determined. A resistance measurement unit to measure,
A storage unit for accumulating the resistance value measured by the resistance measurement unit;
An apparatus for evaluating the soundness of a refractory material supporting stud, comprising: an evaluation unit that evaluates a contact state between the furnace wall surface and the stud based on the resistance value accumulated in the storage unit.   The resistance measuring unit separates the first terminal and the second terminal according to a distance between the two studs among the plurality of studs attached to the furnace wall surface at equal intervals. 8. The soundness evaluation device for a refractory material supporting stud according to claim 7, further comprising a terminal unit attached to a jig.   The first terminal and the second terminal are configured by at least two terminals for voltage measurement and current measurement, respectively, and the resistance measurement unit measures the resistance value using a four-terminal method. The soundness evaluation apparatus for a refractory material supporting stud according to claim 7 or 8, characterized in that:   The soundness evaluation apparatus for a refractory material supporting stud according to any one of claims 7 to 9, wherein a tip of at least one of the first terminal and the second terminal has a rotatable drill shape. A correlation between the resistance value and the contact rate when the contact rate between the stud and the furnace wall surface is different is acquired in advance,
The storage unit stores the correlation between the resistance value and the contact rate, and the evaluation unit obtains the contact rate from the resistance value based on the correlation, and calculates the contact rate. 11. The device for evaluating the soundness of a refractory material supporting stud according to claim 7, wherein the contact state is evaluated based on the refractory material supporting stud.

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