JP5199960B2 - Boiler furnace evaporator tube inspection device and inspection method - Google Patents

Description

  The present invention relates to an inspection apparatus and inspection method for a boiler furnace evaporation tube, and in particular, the surface shape of the evaporation tube disposed in the boiler furnace is measured by a displacement sensor, and the corrosion of the evaporation tube is measured based on the measured value. The present invention relates to an inspection apparatus and an inspection method for evaluating the degree.

  Conventionally, in a land boiler intended for power generation, the combustion atmosphere in the boiler furnace has a strong reducing property, and therefore, the thinning of the evaporation pipe due to sulfide corrosion has been a problem.

  For example, visual inspection (inspection of surface irregularities by visual inspection), tentacle inspection (detection of surface irregularities by bare hands), and ultrasonic thickness gauge can be used to identify the location where damage due to sulfide corrosion has progressed. The test used is mentioned. However, since sulfidation corrosion causes damage over a wide range in the furnace, such an inspection method requires a great deal of labor and time.

  In view of this, an inspection apparatus for simply and quickly inspecting the wear state of the evaporator tube in the boiler furnace has been proposed.

  For example, Patent Document 1 describes an inspection apparatus having an optical sensor that inspects the outer surface of a heat transfer tube of a boiler in a non-contact manner. This inspection device is installed in the heat transfer tube cavity, and moves the optical sensor with respect to the heat transfer officer group in the heat transfer tube bank to obtain the degree of wear of the heat transfer tube.

Japanese Patent Laid-Open No. 9-257714

  However, Patent Document 1 has no specific description about a method for obtaining the degree of wear (that is, the amount of thinning) of the heat transfer tube from the detection result of the outer surface of the heat transfer tube by the optical sensor.

  In addition, the evaporator tube may be welded in advance in consideration of thinning due to sulfidation corrosion, or may be welded according to the amount of thinning over time. FIG. 17 is a view showing the shape of the build-up welded evaporator tube, (a) is a plan view of the evaporator tube, and (b) is a cross-sectional view of the evaporator tube. As shown in the figure, the build-up welded evaporation pipe 4 is provided with a build-up portion 4B around the base tube 4A, and a wave pattern 4C is generated on the surface of the build-up portion 4B during the build-up welding. To do. The evaporative pipe 4 welded in this way has a surface shape that varies greatly depending on the position of the evaporative pipe 4 in the axial direction (see FIG. 17A).

  For this reason, even if the outer surface of the build-up welded evaporation tube (heat transfer tube) is detected by an optical sensor by the inspection device described in Patent Document 1, from this detection result, the build-up welded evaporation tube We cannot know the amount of thinning accurately.

  The present invention has been made in view of the above-described circumstances, and it is an inspection of a boiler furnace evaporation tube that can accurately calculate the amount of thinning of the evaporation tube even when the evaporation tube is build-up welded. An object is to provide an apparatus and an inspection method.

  An inspection apparatus for a boiler furnace evaporation pipe according to an aspect of the present invention is an inspection apparatus for a boiler furnace evaporation pipe that inspects a thinning state of a plurality of evaporation pipes arranged in the boiler furnace, and is fixed to the evaporation pipe. A displacement sensor that measures the surface shape of the evaporation tube that is supported by the support portion and includes a reference mark that indicates a reference position of the evaporation tube, and the reference mark in a state where there is no thinning. The storage means storing the reference surface shape of the evaporating tube and the surface shape measured by the displacement sensor based on the reference mark are superimposed on the reference surface shape stored in the storage means, And calculating means for calculating a thinning amount of the evaporation tube by obtaining a difference between the surface shape and the reference surface shape.

  In the inspection apparatus of the above aspect, based on the reference mark, the surface shape of the evaporation tube measured by the displacement sensor is superimposed on the reference surface shape of the evaporation tube in a state where there is no thinning, and the difference between the two is used to determine the evaporation tube. Calculate the amount of thinning. For this reason, even if the evaporation pipe is welded and the surface shape differs greatly depending on the axial position of the evaporation pipe, the surface shape at the same position and the reference surface shape can be superimposed based on the reference mark. As a result, the thickness reduction of the evaporator tube can be accurately calculated.

  In the inspection apparatus according to the above aspect, it is preferable that the reference mark is provided on the evaporation pipe.

  As a result, the surface shape of the evaporation tube measured by the displacement sensor and the reference surface shape of the evaporation tube in the absence of thinning can be superimposed more accurately, improving the calculation accuracy of the amount of thinning of the evaporation tube. It becomes possible to make it.

  The inspection apparatus according to the aspect described above further includes a moving unit that moves the displacement sensor along the axial direction of the evaporation tube, and the displacement sensor is moved along the axial direction of the evaporation tube by the moving unit. The surface of the evaporating tube is irradiated with a laser beam in the form of a strip (slit) along the radial direction of the evaporating tube (the direction perpendicular to the axial direction of the evaporating tube), and based on the reflected light from the evaporating tube It is preferable to measure the shape.

  In this way, the surface shape of the evaporation tube can be quickly measured by irradiating the strip-shaped laser light along the radial direction of the evaporation tube while moving the displacement sensor along the axial direction of the evaporation tube. .

  In this case, the reference mark is a reference block having a concave portion whose deepest portion is a V-shape along the radial direction of the evaporation tube, and is stored in the storage surface and the surface shape of the evaporation tube. The reference surface shape of the evaporation tube is measured while the displacement sensor is moved along the axial direction of the evaporation tube by the moving means with the deepest portion of the concave portion of the reference block as a measurement start position. More preferably.

  As described above, the measurement of the surface shape of the evaporation tube and the reference surface shape is started from a common position (that is, the deepest portion of the V-shape of the reference block), so that the superposition of the surface shape and the reference surface shape can be easily performed. It can be carried out.

  In the inspection apparatus of the above aspect, the reference mark may be a convex portion indicating the reference position of the evaporation tube, or may be a concave marking indicating the reference position of the evaporation tube.

  Thereby, the position alignment operation | work of a displacement sensor can be abbreviate | omitted at the time of the test | inspection of an evaporation pipe (specifically at the time of the measurement of the surface shape of the evaporation pipe by a displacement sensor).

  In the inspection apparatus according to the above aspect, the reference mark may be a spatter attached during overlay welding of the evaporation tube.

  In this way, by using the spatter that adheres during overlay welding as a reference mark, the labor for forming the reference mark can be saved.

  An inspection apparatus for a boiler furnace evaporation pipe according to another aspect of the present invention is an inspection apparatus for a boiler furnace evaporation pipe that inspects a thinning state of a plurality of evaporation pipes arranged in the boiler furnace, A fixed support portion, a positioning member that aligns the support portion, a displacement sensor that is supported by the support portion that is aligned by the positioning member and that measures the surface shape of the evaporation tube, and the displacement sensor A storage means that stores a reference surface shape of the evaporation tube measured in advance in a state where there is no thinning, and the surface shape measured by the displacement sensor is changed to the reference surface shape stored in the storage means. And a calculating means for calculating a thinning amount of the evaporation tube by superposing and obtaining a difference between the surface shape and the reference surface shape.

  In the inspection apparatus of the above aspect, the surface shape of the evaporation tube and the reference surface shape measured by the displacement sensor are overlapped with each other, and the thickness reduction of the evaporation tube is calculated from the difference between the two. Here, the displacement sensor is supported by a support portion fixed at a predetermined position by a positioning member when measuring the surface shape and the reference surface shape of the evaporation tube. Further, the size of the support portion is constant, and the origin position of the displacement sensor with respect to the support portion is determined. For this reason, even when the evaporator tube is welded and the surface shape is greatly different depending on the axial position of the evaporator tube, the surface shape and the reference surface shape at the same position can be superimposed. The amount of thinning can be calculated accurately.

  In the inspection apparatus according to the above aspect, the support portion includes four quadrangular columnar support columns erected on the evaporation pipe, and the positioning member corresponds to two or more of the support columns of the support portion. It is preferable that there are a plurality of square contacts provided at the positions.

  Thereby, a support part can be aligned with high precision and the thickness reduction amount of an evaporation pipe can be calculated still more correctly.

  The inspection apparatus according to the aspect described above further includes a moving unit that moves the displacement sensor along the axial direction of the evaporation tube, and the displacement sensor is moved along the axial direction of the evaporation tube by the moving unit. Irradiate a strip-shaped laser beam along the radial direction of the evaporation tube (a direction orthogonal to the axial direction of the evaporation tube), and measure the surface shape of the evaporation tube based on the reflected light from the evaporation tube It is preferable.

  In this way, the surface shape of the evaporation tube can be quickly measured by irradiating the strip-shaped laser light along the radial direction of the evaporation tube while moving the displacement sensor along the axial direction of the evaporation tube. .

  An inspection method for a boiler furnace evaporation pipe according to an aspect of the present invention is an inspection method for a boiler furnace evaporation pipe for inspecting a thinning state of a plurality of evaporation pipes arranged in the boiler furnace, and the reference for the evaporation pipe A step of forming a reference mark indicating a position; a step of measuring a reference surface shape of the evaporation tube including the reference mark in a state where there is no thinning; and storing the reference surface shape measured in advance in a storage unit And measuring the surface shape of the evaporation tube including the reference mark, and superimposing the measured surface shape on the reference surface shape stored in the storage means based on the reference mark. And calculating a thickness reduction amount of the evaporation tube by obtaining a difference between the surface shape and the reference surface shape.

  In the inspection method of the above aspect, based on the reference mark, the measured surface shape of the evaporation tube and the reference surface shape of the evaporation tube in the absence of thinning are superimposed, and the amount of reduction in the evaporation tube is calculated from the difference between the two. Is calculated. For this reason, even if the evaporation pipe is welded and the surface shape differs greatly depending on the axial position of the evaporation pipe, the surface shape at the same position and the reference surface shape can be superimposed based on the reference mark. As a result, the thickness reduction of the evaporator tube can be accurately calculated.

  A boiler furnace evaporation tube inspection method according to another aspect of the present invention is a boiler furnace evaporation tube inspection method for inspecting a thinning state of a plurality of evaporation tubes disposed in a boiler furnace, and is positioned by a positioning member. A step of measuring in advance a reference surface shape of the evaporation tube in a state where there is no thinning, and a step of storing the reference surface shape measured in advance in a storage means by a displacement sensor supported by the combined support portion Measuring the surface shape of the evaporating tube by the displacement sensor supported by the support portion aligned with the positioning member, and storing the measured surface shape in the storage means. And a step of calculating a thinning amount of the evaporating tube by obtaining a difference between the surface shape and the reference surface shape so as to overlap with the reference surface shape.

  In the inspection method of the above aspect, the surface shape of the evaporation tube and the reference surface shape measured by the displacement sensor are overlapped with each other, and the thickness reduction of the evaporation tube is calculated from the difference between the two. Here, the displacement sensor is supported by a support portion fixed at a predetermined position by a positioning member when measuring the surface shape and the reference surface shape of the evaporation tube. Further, the size of the support portion is constant, and the origin position of the displacement sensor with respect to the support portion is determined. For this reason, even when the evaporator tube is welded and the surface shape is greatly different depending on the axial position of the evaporator tube, the surface shape and the reference surface shape at the same position can be superimposed. The amount of thinning can be calculated accurately.

  According to the present invention, even when the evaporator tube is overlay welded and the surface shape is greatly different depending on the axial position of the evaporator tube, the surface shape and the reference surface shape at the same position can be superimposed, The amount of thinning of the evaporator tube can be calculated accurately.

It is a perspective view which shows the structural example of a boiler furnace. It is a figure which shows an example of a boiler furnace evaporation pipe. It is a figure which shows the other example of a boiler furnace evaporation pipe. It is a perspective view which shows the structural example of the inspection apparatus of a boiler furnace evaporation pipe. It is a figure which shows the arrangement | positioning relationship between the displacement sensor of the inspection apparatus shown in FIG. 4, and an evaporation pipe. It is a figure which shows the structural example of a refracting means. It is a perspective view which shows an example of the reference mark which shows the reference position of an evaporation pipe. It is a block diagram which shows the structural example of a signal processing apparatus. It is a flowchart which shows an example of the inspection method of an evaporation pipe. It is a figure which shows an example of displacement measurement data. It is a figure which shows a mode that the position of an evaporation pipe, a weld metal, and a fin is specified, (a) shows a surface shape curve, (b) is a graph which differentiated the surface shape curve of (a) to the first order. It is a figure which shows a mode that a surface shape curve is correct | amended. It is a figure which shows a mode that a surface shape curve is correct | amended. It is a figure which shows a mode that the surface shape of the evaporation pipe was piled up on the reference | standard surface shape. It is a figure which shows the other example of a reference | standard mark. It is a top view which shows a mode that an evaporation pipe is test | inspected in the state which aligned the support part of the displacement sensor. It is a figure which shows the structural example of the evaporation pipe by which overlay welding was carried out.

  Hereinafter, the inspection apparatus and the inspection method according to an embodiment of the present invention will be described after describing the inspection target of the boiler furnace evaporation pipe inspection apparatus and the inspection method according to the present invention.

  FIG. 1 is a perspective view showing a configuration example of a boiler furnace to which an inspection apparatus and an inspection method according to the present invention are applied. FIG. 2 is a view showing an example of a boiler furnace evaporation pipe which is an inspection object of the inspection apparatus and inspection method according to the present invention, and FIG. 3 is a view showing another example of the boiler furnace evaporation pipe. 2 (a) and 3 (a) are plan views showing the boiler furnace evaporation pipe, and FIGS. 2 (b) and 3 (b) are cross-sectional views of the boiler furnace evaporation pipe.

  As shown in FIG. 1, the boiler furnace 1 includes a combustion chamber 2 surrounded by a wall surface 3 and a plurality of evaporation tubes 4 arranged along the wall surface 3. The combustion chamber 2 is provided with a burner (not shown), and the evaporation pipe 4 is heated by combustion of the burner, and water flowing inside the evaporation pipe 4 is evaporated to generate steam.

  The evaporation pipes 4 may be fixed to each other by welding with the adjacent evaporation pipes 4 or may simply be arranged so as to contact each other.

  For example, as shown in FIG. 2, adjacent evaporation pipes 4 may be fixed to each other by welding via fins 8. The fins 8 are plate-like members extending along the axial direction of the evaporation tube 4, and both side ends of the fins 8 are welded to the evaporation tube 4 by weld metal 10. When the plurality of evaporation tubes 4 are welded to each other through the fins 8 as described above, the space surrounded by the evaporation tubes 4 can be used as the combustion chamber 2 by using the arranged evaporation tubes 4 as the wall surfaces 3.

  Moreover, as shown in FIG. 3, the evaporation pipe 4 is a rose pipe to which upper and lower ends (not shown) are fixed, and the adjacent evaporation pipes 4 may be arranged so as to contact each other.

  The evaporation pipe 4 may be an elementary pipe or a welded weld. For example, the part where the evaporator tube 4 is easily corroded may be welded in advance, or the part where the evaporator pipe 4 is corroded may be welded according to the thickness reduction. Further, the evaporation pipe 4 may be a smooth pipe having a smooth inside, or a rifle pipe having a spiral groove formed inside the pipe.

  In this embodiment, in order to inspect the thinning state of the evaporation pipe 4 having the above-described configuration, an inspection device described below is used.

  FIG. 4 is a perspective view showing a configuration example of the boiler furnace evaporation pipe inspection apparatus according to the present embodiment. 5A and 5B are diagrams showing the positional relationship between the displacement sensor and the evaporation tube of the inspection apparatus shown in FIG.

  As shown in FIG. 4, the inspection apparatus 11 mainly includes a support portion 14 fixed to the evaporation tube 4, a displacement sensor 12 that is supported by the support portion 14 and measures the surface shape of the evaporation tube 4, and the displacement sensor 12. And a signal processing device 16 (corresponding to “storage means” and “calculation means”) for processing the measurement signal from.

  The support portion 14 is not particularly limited as long as it can support the displacement sensor 12. For example, as shown in FIG. 4, four support columns 20 that are erected and fixed to the evaporation pipe 4 and a pair of support columns 14 are provided. A beam 24 (24A, 24B) installed between the columns 20 and a rail 26 installed between the beams 24 (24A, 24B) can be used. In this example, the displacement sensor 12 is directly supported by the support frame 28 formed by the beams 24 (24 A and 24 B) and the rail 26, and the support frame 28 is supported by the support column 20.

  Moreover, the support | pillar 20 is attached to the evaporation pipe 4 via the seat surface 22 formed in the circular arc so that the surface shape of the evaporation pipe 4 may be followed. The column 20 may be attached to the evaporation tube 4 by using any fastening component. However, the magnet 18 is disposed between the column 20 and the seating surface 22 and the magnetic force of the magnet 18 is used to support the column 20. Is preferably attached to the evaporator tube 4. By using the magnet 18, the support portion 14 can be easily removed.

  The support columns 20 are fixed to the two evaporation tubes 4 so as to be positioned at two corners of the square or rectangle along the axial direction of the evaporation tubes 4.

  The beam 24 is configured by a screw mechanism so that the vertical position can be adjusted with respect to the support column 20, and the vertical adjustment knob portion 29 is rotated to move the slit 30 formation range in the Z-axis direction (the direction of arrow a). It is supposed to move.

  The rail 26 is configured to be movable in the axial direction of the beam 24 by a screw mechanism, and is moved in the X-axis direction (the direction of the arrow b) by rotating the left / right adjustment knob portion 31.

  The displacement sensor 12 is supported by the support portion 14 configured as described above so as to be movable in the Z-axis direction (arrow a direction) and the X-axis direction (arrow b direction).

  The displacement sensor 12 is not particularly limited as long as the outer surface shape of the evaporation tube 4 can be measured. For example, a sensor having a measurement method such as a confocal type, a triangulation type, or a two-dimensional triangulation type is used. be able to. In particular, the two-dimensional triangulation type two-dimensional laser displacement sensor has a configuration capable of instantaneously measuring the height of the measurement object relative to the position in the width direction (a configuration capable of two-dimensional measurement). By measuring the surface shape of the evaporation tube 4 while moving the three-dimensional laser displacement sensor along the axial direction of the evaporation tube 4, the evaporation tube 4 can be inspected quickly. Hereinafter, a case where a two-dimensional laser displacement sensor is used as the displacement sensor 12 will be described as an example.

  As shown in FIG. 4, the displacement sensor (two-dimensional laser displacement sensor) 12 includes a sensor head 32 having a laser beam irradiation part 34 and a light receiving element (not shown), and the sensor head 32 along the rail 26. Motor 33 that moves in the axial direction (Y-axis direction), and an encoder 36 that outputs a movement distance signal of the sensor head 32 from the rotation angle of the motor 33.

  As shown in FIGS. 5A and 5B, the laser beam irradiation unit 34 irradiates the evaporation tube 4 with a belt-shaped (slit-shaped) laser beam along the radial direction (X-axis direction) of the evaporation tube 4. It is like that. 5A shows the irradiation state of the laser light when the evaporation tube 4 is connected by the fins 8, and FIG. 5B shows the evaporation tube 4 being a rose tube, and the adjacent evaporation tube. 4 shows the irradiation state of the laser beam in the case of being arranged in contact with 4.

  The strip-shaped laser light irradiated on the evaporation tube 4 is reflected by the surface of the evaporation tube 4, measured by a light receiving element (not shown) of the sensor head 32, and a direction perpendicular to the axial direction of the evaporation tube 4 (radial direction, The outer surface shape of the evaporation pipe 4 along the X-axis direction) is measured. By repeating the measurement by the sensor head 32 while moving the sensor head 32 along the axial direction of the evaporation tube 4 (Y-axis direction shown in FIG. 4) by the motor 33, the evaporation tube 4 is extended over the entire length of the evaporation tube 4. The outer surface shape can be measured.

  Further, the position of the sensor head 32 in the Z-axis direction is a measurement in which the distance between the sensor head 32 and the evaporation tube 4 is determined according to the focal length of the laser beam irradiation unit 34 using the vertical adjustment knob 29 (see FIG. 4). It is adjusted to be within the possible range.

  When the position of the sensor head 32 in the Z-axis direction cannot be adjusted within the measurable range simply by turning the vertical adjustment knob 29, a refracting unit that refracts the laser beam may be used.

  FIG. 6 is a diagram showing a refracting means for refracting laser light. 6A shows an example using a prism 41 that refracts laser light 35 as a refracting means, and FIG. 6B shows an example using a mirror 43 that refracts (reflects) laser light 35 as a refracting means. Is shown. Thus, by refracting the laser beam 35 using the refracting means (41, 43), the position of the sensor head 32 in the Z direction cannot be adjusted within the measurable range only by turning the vertical adjustment knob 29. Even in this case, the position of the sensor head 32 in the Z direction can be adjusted appropriately. In particular, when the inspection of the evaporator tube of the boiler furnace is performed on a scaffold installed in the furnace, a sufficient interval between the scaffold and the evaporator tube 4 may not be secured. It is preferable to use a refracting means.

  By the way, the evaporative tube 4 may be build-up welded in advance in consideration of thinning due to sulfidation corrosion, or may be build-up welded according to the amount of thinning over time. Since the surface of the welded evaporator tube 4 is greatly different depending on the position of the evaporator tube 4 in the axial direction, even if the outer surface of the evaporator tube 4 is measured by the displacement sensor 12, the measurement result shows that the evaporator tube 4 We cannot know the amount of thinning accurately.

  Therefore, in the present embodiment, a reference mark indicating the reference position of the evaporation tube 4 is provided so that the thickness reduction amount of the evaporation tube 4 can be accurately calculated even when the evaporation tube 4 is build-up welded. Pre-formed.

  FIG. 7 is a perspective view showing an example of a reference mark provided on the evaporation pipe 4. As shown in the figure, the reference mark 60 is a reference block in which the deepest portion 64 has a V-shaped recess 62 along the radial direction of the evaporation tube 4, and is fixed to the evaporation tube 4 by any method such as welding. Has been. The reference mark 60 is preferably provided on each of the evaporation tubes 4 to be inspected from the viewpoint of performing the thinning amount evaluation of the evaporation tube 4 with high accuracy. Although FIG. 7 shows one reference mark 60 provided on one evaporator tube 4, one reference mark 60 may be provided across a plurality of evaporator tubes 4 (that is, one reference mark 60). The mark 60 may be shared by the plurality of evaporation tubes 4).

  The surface shape of the evaporation tube 4 including the reference mark 60 is measured by the displacement sensor 12 and superimposed on the reference surface shape of the evaporation tube 4 including the reference mark 60 to obtain a difference between the two, thereby reducing the evaporation tube 4. The amount of meat is calculated. Thereby, even when the evaporation pipe 4 is build-up welded and the surface shape is greatly different depending on the axial position of the evaporation pipe 4, the surface shape and the reference surface shape at the same position can be superimposed. The thinning amount of the tube 4 can be accurately calculated. Here, the reference surface shape of the evaporation tube 4 is the surface shape of the evaporation tube 4 in a state where there is no thinning, and is stored in advance in a reference shape storage unit of the signal processing device 16 described later.

  When the reference mark 60 having the above-described configuration is used, it is preferable that the surface shape of the evaporation tube 4 and the measurement of the reference surface shape start from the deepest portion 64 of the reference mark 60. As a result, the measured surface shape of the evaporation tube 4 and the reference surface shape can be easily overlapped, so that it is possible to reduce the calculation load required for calculating the thickness reduction of the evaporation tube 4.

  The signal processing device 16 shown in FIG. 4 is connected to the sensor head 32 and the encoder 36 of the displacement sensor 12 and receives signals from the sensor head 32 and the encoder 36 to calculate the thickness reduction amount of the evaporation pipe 4.

  FIG. 8 is a block diagram illustrating a configuration example of the signal processing device 16. As shown in the figure, the signal processing device 16 mainly includes a controller 40 that receives an output signal of the displacement sensor 12, a PC (inspector's personal computer) 42 that stores displacement measurement data in an internal memory, and a reference surface shape. Is stored in the reference shape storage unit 46, and a thinning amount calculation unit 48 that calculates the thinning amount.

  In the signal processing device 16, the controller 40 receives the displacement measurement data from the displacement sensor 12, stores it in the internal memory of the PC 42, and the thinning amount calculation unit 48 stores the reference shape data stored in advance in the reference shape storage unit 46. And the amount of thinning is calculated by obtaining the difference between the two.

  The reference shape storage unit 46 stores a reference surface shape of the evaporation tube 4 including the reference mark 60 in a state where there is no thinning. The reference surface shape is stored for each of the evaporation tubes 4, and the reference surface shape corresponding to the evaporation tube 4 whose surface shape is measured by the displacement sensor 12 is sent from the reference shape storage unit 46 to the thinning amount calculation unit 48. It is supposed to be.

  Further, since the displacement measurement data may include an error due to the mounting state (position or angle) of the displacement sensor 12, as shown in FIG. 8, a correction unit 44 for correcting the displacement measurement data is provided. It is preferable. Thereby, the thinning amount of the evaporation pipe 4 can be calculated more accurately regardless of the attachment state of the displacement sensor 12. The displacement measurement data correction process performed by the correction unit 44 will be described in detail later.

  Next, a method for inspecting the evaporation tube 4 using the above-described inspection apparatus 11 will be described. FIG. 9 is a flowchart showing an example of an inspection method for the evaporation tube 4.

  As shown in the figure, first, in step S <b> 2, the signal processing device 16 acquires displacement measurement data from the displacement sensor 12 via the controller 40. As shown in FIG. 10, the displacement measurement data takes the furnace width direction distance (distance in the X axis direction shown in FIG. 4) as the horizontal axis, and the surface shape data D of the evaporation tube 4 is acquired as the displacement from the position of the sensor head 32. The

  In step S4, the part of the evaporator tube 4, the part of the weld metal 10, and the part of the fin 8 are recognized from the surface shape acquired by the reference position calculator 46.

  Specifically, as shown in FIG. 11A, when the horizontal axis represents the furnace width direction distance and the vertical axis represents the height of the chevron surface shape, (1) and (6) are the portions of the fin 8. (2) and (5) correspond to the weld metal 10 portion, and (3) to (4) correspond to the evaporation tube 4 portion.

  In order to obtain these positions from the measurement data, it is possible to obtain the slope by calculating the first-order differentiation of the curve of the surface shape of the mountain shape.

  FIG. 11B shows the first-order differential data, and the inclination is substantially zero at the fin 8 portions of (1) and (6), and the weld metal 10 portions of (2) and (5) are also welded. Since the metal 10 is deposited, the inclination becomes substantially zero.

  Furthermore, two peak values of inclination appear on each of the plus side and the minus side, and the position of the first peak value in the horizontal axis direction is a changing portion from the fin 8 to the weld metal 10, and the second peak value position (3 ) Is a changing part from the weld metal 10 to the evaporation pipe 4, and this position (3) can be determined as the boundary position P between the weld metal 10 and the evaporation pipe 4, and (3) to (4) are the evaporation pipe 4. It turns out that it is the surface part of.

  Next, the process proceeds to step S6 shown in FIG. 9, and correction processing of the displacement measurement data by the correction unit 44 is performed. 12A and 12B are diagrams illustrating correction processing of displacement measurement data by the correction unit 44. FIG. 12A and 12B, the dotted line indicates the shape position before correction, and the solid line indicates the shape position after correction.

  As shown in FIG. 12 (a), the correction unit 44 reduces the thickness of the design data or the like when the position of the fin (1), (6) or the boundary position (3) (4) obtained from the measurement data is When there is a deviation from the fin position or the boundary position of the reference shape having no gap, correction is made to move up and down to match.

  The correction unit 44 also determines that the heights of the positions (1) and (6) of the surface-shaped fins 8 obtained from the measurement data or the heights of the boundary positions (3) and (4) do not coincide with each other. As shown in FIG. 12 (b), correction is performed so that the circumferential direction of the evaporator tube 4 is rotated by θ to coincide with the horizontal direction.

  Further, since the displacement sensor 12 is not scanned in parallel to the axial direction of the evaporation tube 4, the correction unit 44, when there is a deviation in the left-right direction between the displacement measurement data, as shown in FIG. The boundary position between the fin and the fin (or the boundary position between the pipe and the weld) is detected manually or automatically, and the deviation x between the first data of the surface shape data D and the last data is calculated. Corrects the horizontal shift of the. The deviation xi is calculated by xi = ni × d × tan θ ′.

  Next, in step S <b> 8 shown in FIG. 9, reference surface shape data of the evaporation tube 4 in a state where there is no thinning is acquired from the reference shape storage unit 46.

  Then, in step S10, the displacement measurement data corrected in step S6 (data indicating the current surface shape of the evaporation tube 4) and the reference surface shape data (reduced in step S8) by the thinning amount calculation unit 48 in step S10. And the data showing the surface shape of the evaporation tube 4 in a state where there is no meat). FIG. 14 is a diagram illustrating a state in which the displacement measurement data is superimposed on the reference surface shape data. As shown in the figure, the displacement measurement data and the reference surface shape data are in the same position in the left-right direction (that is, the surface position of the fin 8 and the boundary position between the weld metal 10 and the evaporation tube 4 are matched). Is superimposed.

  In this embodiment, the displacement measurement data and the reference surface shape data are superimposed based on the reference mark 60. Specifically, based on the reference mark 60, the displacement measurement data at the same position in the axial direction (longitudinal direction) of the evaporation tube 4 and the reference surface shape data are superimposed. Thereby, even if the evaporation pipe 4 is build-up welded, the thinning amount of the evaporation pipe 4 can be accurately calculated.

  Finally, in step S12, the difference between the displacement measurement data superimposed in step S10 and the reference surface shape data is obtained, and the thickness reduction amount of the evaporation tube 4 is calculated.

  Although an example of the present invention has been described in detail above, the present invention is not limited to this, and it goes without saying that various improvements and modifications may be made without departing from the gist of the present invention.

  For example, in the above-described embodiment, an example in which the reference mark is the reference block 60 having the V-shaped recess 62 has been described. However, the reference mark is not particularly limited as long as it is a mark indicating the reference position of the evaporation tube 4.

  15A to 15C are perspective views showing other examples of the reference mark. The reference mark 70 shown in FIG. 15A is a convex portion indicating the reference position of the evaporation tube 4, and may be a metal plate fixed to the evaporation tube 4 by welding, for example. The reference mark 72 shown in FIG. 15B is a concave marking indicating the reference position of the evaporator tube 4, and may be any character or figure stamped on the evaporator tube 4, for example. FIGS. 15A and 15B show an example in which the reference mark (70, 72) is formed on the evaporation pipe 4 to be inspected, but the reference mark (70, 72) is the object to be inspected. May be formed on the evaporation pipe 4 (for example, an evaporation pipe adjacent to the evaporation pipe to be inspected), or may be formed on the fin 8 or the weld metal 10.

  By using the reference marks (70, 72) shown in FIGS. 15A and 15B, when the evaporator tube 4 is inspected (specifically, when the surface shape of the evaporator tube 4 is measured by the displacement sensor 12). The positioning operation of the displacement sensor 12 can be omitted.

  Further, as shown in FIG. 15 (c), the displacement measurement data (data indicating the surface shape of the evaporation tube 4) and the reference surface are formed by using the reference mark 74 made of spatter adhered during the overlay welding of the evaporation tube 4. Shape data (data indicating the surface shape of the evaporation tube 4 in a state where there is no thinning) may be superimposed. The reference mark 74 may be spatter formed on the evaporation pipe 4 that is not the inspection target (for example, the evaporation pipe adjacent to the inspection target evaporation pipe), or spatter formed on the fin 8 or the weld metal 10. There may be. Thus, by using the spatter adhering at the time of overlay welding as the reference mark 74, the trouble of forming the reference mark can be saved.

  In the above-described embodiment, the example in which the thickness reduction amount is calculated by superimposing the displacement measurement data and the reference surface shape data based on the reference mark has been described. Instead of using the reference mark, the support portion of the displacement sensor 12 is used. The thickness reduction amount may be calculated by superimposing the displacement measurement data acquired in a state in which 14 is aligned with the reference surface shape data.

  FIG. 16 is a plan view showing a state in which the evaporator tube 4 is inspected in a state where the support portion 14 of the displacement sensor 12 is aligned. As shown in the figure, a positioning member 80 for aligning the support portion 14 is fixed to the evaporation pipe 4.

  The positioning member 80 is not particularly limited as long as the support member 14 can be positioned. For example, the positioning member 80 may be a square contact provided at a position corresponding to the square columnar support column 20. In particular, as shown in FIG. 16, a corner pad provided at a position corresponding to the lower corner of the support column 20 in the vertical direction is preferable because the support portion 14 can be easily positioned. The positioning members 80 are preferably provided at positions corresponding to two or more of the support pillars 20 from the viewpoint of improving the positioning accuracy of the support portion 14.

  The displacement sensor 12 supported by the support portion 14 in a state of being aligned by the positioning member 80 measures the surface shape and the reference surface shape of the evaporation pipe 4, and superimposes them on each other to obtain a difference, thereby evaporating. The amount of thinning of the tube 4 is calculated. Here, the displacement sensor 12 is supported by the support portion 14 fixed at a predetermined position by the positioning member 80 when measuring the surface shape and the reference surface shape of the evaporation tube 4. The size of the support portion 14 is constant, and the origin position of the displacement sensor 12 with respect to the support portion 14 is determined. For this reason, even if the evaporation pipe 4 is build-up welded and the surface shape is greatly different depending on the axial position of the evaporation pipe 4, the surface shape and the reference surface shape at the same position can be superimposed. The thinning amount of the tube 4 can be accurately calculated.

DESCRIPTION OF SYMBOLS 1 Boiler furnace 2 Combustion chamber 4 Evaporation pipe 8 Fin 11 Inspection apparatus 12 Displacement sensor 14 Support part 16 Signal processing apparatus 18 Magnet 20 Support column 28 Support frame 29 Vertical adjustment knob part 31 Left and right adjustment knob part 32 Sensor head 33 Motor 34 Laser irradiation Part 40 Controller 42 PC
44 Correction unit 46 Reference shape storage unit 48 Thinning amount calculation unit 60, 70, 72, 74 Reference mark 80 Positioning member

Claims (12)

A boiler furnace evaporating pipe inspection device for inspecting a thinning state of a plurality of evaporating pipes arranged in a boiler furnace,
A support portion fixed to the evaporation tube;
A displacement sensor that is supported by the support and measures a surface shape of the evaporation tube including a reference mark indicating a reference position of the evaporation tube;
Storage means for storing a reference surface shape of the evaporation tube including the reference mark in a state where there is no thinning;
Based on the reference mark, the surface shape measured by the displacement sensor is superposed on the reference surface shape stored in the storage means to obtain a difference between the surface shape and the reference surface shape. An inspection apparatus for a boiler furnace evaporation pipe, comprising: a calculating means for calculating a thinning amount of the evaporation pipe.   The inspection apparatus for a boiler furnace evaporation pipe according to claim 1, wherein the reference mark is provided on the evaporation pipe. A moving means for moving the displacement sensor along the axial direction of the evaporation pipe;
The displacement sensor irradiates a belt-like laser beam along the radial direction of the evaporation tube while moving along the axial direction of the evaporation tube by the moving means, and based on the reflected light from the evaporation tube 3. The inspection apparatus for a boiler furnace evaporation tube according to claim 1, wherein the surface shape of the evaporation tube is measured. The reference mark is a reference block having a concave portion whose deepest portion is a V shape along the radial direction of the evaporation tube,
The surface shape of the evaporating tube and the reference surface shape of the evaporating tube stored in the storage means are determined so that the displacement sensor is the moving means with the deepest portion of the concave portion of the reference block as a measurement start position. The boiler furnace evaporation pipe inspection apparatus according to claim 3, wherein the inspection apparatus is measured while moving along the axial direction of the evaporation pipe.   4. The inspection apparatus for a boiler furnace evaporation tube according to claim 1, wherein the reference mark is a convex portion that indicates the reference position of the evaporation tube. 5.   4. The inspection apparatus for a boiler furnace evaporation tube according to claim 1, wherein the reference mark is a concave marking indicating the reference position of the evaporation tube. 5.   4. The inspection apparatus for a boiler furnace evaporation tube according to claim 1, wherein the reference mark is a sputter adhered during overlay welding of the evaporation tube. 5. A boiler furnace evaporating pipe inspection device for inspecting a thinning state of a plurality of evaporating pipes arranged in a boiler furnace,
A support portion fixed to the evaporation tube;
A positioning member for aligning the support part;
A displacement sensor which is supported by the support portion aligned by the positioning member and measures the surface shape of the evaporation tube;
Storage means for storing a reference surface shape of the evaporation pipe measured in advance by the displacement sensor and in a state without thinning;
The surface thickness measured by the displacement sensor is overlaid on the reference surface shape stored in the storage means, and the difference between the surface shape and the reference surface shape is obtained to reduce the amount of thinning of the evaporation tube A boiler furnace evaporator tube inspection apparatus comprising: a calculating means for calculating The support portion includes four quadrangular columnar support columns that are erected on the evaporation pipe,
9. The boiler furnace evaporator tube inspection device according to claim 8, wherein the positioning member is a plurality of square contacts provided at positions corresponding to two or more of the support columns of the support portion. A moving means for moving the displacement sensor along the axial direction of the evaporation pipe;
The displacement sensor irradiates a belt-like laser beam along the radial direction of the evaporation tube while moving along the axial direction of the evaporation tube by the moving means, and based on the reflected light from the evaporation tube 10. The inspection apparatus for a boiler furnace evaporation tube according to claim 8, wherein the surface shape of the evaporation tube is measured. A method for inspecting a boiler furnace evaporation pipe for inspecting a thinning state of a plurality of evaporation pipes arranged in a boiler furnace,
Forming a reference mark indicating a reference position of the evaporation tube;
In a state where there is no thinning, a step of measuring a reference surface shape of the evaporation tube including the reference mark in advance,
Storing the reference surface shape measured in advance in a storage means;
Measuring the surface shape of the evaporation tube including the reference mark;
Based on the reference mark, the measured surface shape is superimposed on the reference surface shape stored in the storage means, and a difference between the surface shape and the reference surface shape is obtained to obtain a difference between the surface shape and the reference surface shape. A method for inspecting a boiler furnace evaporator tube, comprising: a step of calculating a thinning amount. A method for inspecting a boiler furnace evaporation pipe for inspecting a thinning state of a plurality of evaporation pipes arranged in a boiler furnace,
A step of measuring in advance a reference surface shape of the evaporating tube in a state where there is no thinning by a displacement sensor supported by a support portion in a state of being aligned by a positioning member;
Storing the reference surface shape measured in advance in a storage means;
Measuring the surface shape of the evaporation tube by the displacement sensor supported by the support portion in a state of being aligned by the positioning member;
The step of calculating the thinning amount of the evaporating tube by superimposing the measured surface shape on the reference surface shape stored in the storage means and obtaining the difference between the surface shape and the reference surface shape And a method for inspecting a boiler furnace evaporator tube.

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