Method for replacing heat transfer tubes and heat transfer tube replacement device

Abstract

A method for replacing heat transfer tubes that can be easily utilized on-site is provided. A method for replacing heat transfer tubes, based on CAD data (43) of a tube sheet (1) with tube holes (1a), the field of view (45) of a 3D camera, and the camera distance (47), determines multiple camera coordinates (49) as coordinates of a robot arm (11a) for shooting. The robot arm (11a) moves the 3D camera (35) to the camera coordinates (49) and takes a picture of the tube sheet (51) at each camera coordinate (49). The center coordinates of the heat transfer tube (3) or the center coordinates of the tube hole (1a) reflected on the tube sheet image (51) are determined, i.e., the tube hole coordinates (53). Duplicate tube hole coordinates (53) are deleted, and a list of tube hole coordinates (55) is created. The construction sequence, i.e., the hole number (55a), is assigned to the center coordinates (X, Y) of the list of tube hole coordinates (53). The robot arm (11a) expands the tube (3) according to the hole number sequence through the end effector (13) installed at the front end of the robot arm (11a).

Description

Technical Field

[0001] This invention relates to a method for replacing a heat transfer tube and a heat transfer tube replacement device. Background Technology

[0002] An automatic pipe expander is known (e.g., Japanese Patent Application Publication No. 2024-82326). The pipe expander includes an expander, a rotary drive, a clamping device, a clamping moving device, and a conveying device. Summary of the Invention

[0003] The problem that the invention aims to solve Tube expanders are primarily used for the maintenance of heat exchangers. When using automated tube expanders, robot teaching is required. Proficiency in the tube expander technique and the teaching process is essential during this process. Therefore, there are situations where automated tube expanders are difficult to use in the field.

[0004] The purpose of this invention is to provide a method and apparatus for replacing heat transfer tubes that can be easily used on-site.

[0005] Methods for solving problems The first aspect of this invention is a method for replacing a heat transfer tube, wherein, Based on the CAD data of the tube sheet with holes, the field of view of the 3D camera, and the camera distance, multiple camera coordinates are determined. These multiple camera coordinates are the coordinates of the robot arm during the shooting process. The robotic arm moves the 3D camera to the camera coordinates and takes an image of the tube sheet at each camera coordinate. Determine the center coordinates of the heat transfer tubes or the center coordinates of the tube holes, as reflected in the tube sheet image, i.e., the tube hole coordinates. Remove duplicate borehole coordinates and create a list of borehole coordinates. Assign the construction sequence, i.e., the hole number, to the center coordinates of the hole coordinate list. The robotic arm expands the tube according to the hole number sequence using an end effector installed at the front end of the robotic arm.

[0006] The second aspect of this invention is a heat transfer tube replacement device, comprising: Robotic arm; An end effector, which is disposed at the front end of the robot arm and has a drive motor capable of assembling a pipe expander; A 3D camera, the 3D camera being disposed at the fore-end of the robotic arm; and The control device includes a storage device, a computing device, and a robot arm control unit. The storage device stores: CAD data for the tube sheet; The field of view and shooting distance of the 3D camera; Tube sheet image; Pipe coordinates; List of pipe coordinates; and Hole number, The computing device has: The camera coordinate determination unit determines multiple camera coordinates based on the CAD data, the field of view, and the camera distance. These multiple camera coordinates are the coordinates of the 3D camera at the time of shooting. The tube hole coordinate determination unit determines the tilt of the tube plate relative to the robot coordinate system and the tube hole center coordinates (i.e., tube hole coordinates) of the tube plate as reflected on each tube plate image based on the tube plate image, and creates a tube hole coordinate list with duplicate tube hole coordinates deleted. The construction sequence determination unit assigns a construction sequence, i.e., a hole number, to the center coordinates of the borehole coordinate list; and The job program generation unit generates a pipe-expanding operation program for the robotic arm, based on the pipe hole coordinate list, for expanding the pipe by means of the end effector in sequence according to the hole number. The robot arm control unit drives the robot arm and the end effector based on the pipe expansion operation program.

[0007] The third aspect of this invention is a method for replacing a heat transfer tube, wherein, Based on the CAD data of the tube sheet with the tube holes for mounting heat transfer tubes, the field of view of the camera, and the camera distance, multiple camera coordinates are determined. These multiple camera coordinates are the coordinates of the robot arm during the shooting process. The robotic arm moves the camera to the camera coordinates and takes an image of the tube sheet at each camera coordinate. Determine the center coordinates of the heat transfer tube or the center coordinates of the tube hole, as reflected in the tube sheet image, i.e., the tube hole coordinates. Remove duplicate borehole coordinates and create a list of borehole coordinates including the construction sequence. The robot arm expands the heat transfer pipe according to the construction sequence using an end effector installed at the front end of the robot arm.

[0008] The fourth aspect of this invention is a heat transfer tube replacement device, comprising: Robotic arm; An end effector, which is disposed at the front end of the robot arm and has a drive motor capable of assembling a pipe expander; A camera, the camera being disposed at the fore-end of the robotic arm; and The control device includes a storage device, a computing device, and a robot arm control unit. The storage device stores: The field of view and shooting distance of the camera; Tube sheet image; Hole coordinates; and A list of borehole coordinates including the construction sequence. The computing device has: The tube hole coordinate determination unit determines the tilt of the tube plate relative to the robot coordinate system and the tube hole center coordinates (i.e., tube hole coordinates) of the tube plate as reflected on each tube plate image based on the tube plate image, and creates a tube hole coordinate list with duplicate tube hole coordinates deleted. Construction sequence determination unit, wherein the construction sequence determination unit assigns a construction sequence to the center coordinates of the borehole coordinate list; and The work program generation unit generates a pipe-expanding operation program for the robotic arm, based on the pipe coordinate list, for expanding the pipe according to the construction sequence using the end effector. The robot arm control unit drives the robot arm and the end effector based on the pipe expansion operation program.

[0009] Alternatively, based on a 3D tube sheet image, the tilt of the tube sheet relative to the robot coordinate system and the center coordinates of the holes (i.e., the hole coordinates) of the tubes projected onto each tube sheet image can be determined. The tube sheet coordinate system can also be determined based on the tube sheet's reference position and tilt. The hole coordinates can be determined within the tube sheet coordinate system. The tube enlargement operation procedure can also be generated within the tube sheet coordinate system.

[0010] A tube sheet image can be a photograph or video of the tube sheet after the heat transfer tubes have been inserted. Alternatively, a tube sheet image can also be a photograph or video of the tube sheet before the heat transfer tubes have been inserted.

[0011] The specific location of the tube sheet is, for example, the center of the tube sheet or the dimensional reference point of the tube sheet in the CAD data.

[0012] The tube sheet coordinate system is the position coordinate of the tube sheet relative to the robot's reference point, including the tube sheet's tilt relative to the robot. The tube sheet coordinate system can be given as the offset of the coordinates relative to the robot coordinate system.

[0013] The end effector can also have a 3D camera. The end effector can also have a drive motor. The drive motor rotates the tube expander.

[0014] The acceptable range can include both the maximum and minimum values. If the increment is above the minimum value but below the maximum value, it can be considered acceptable.

[0015] The camera determines the relative position and orientation of the imaging device relative to the workpiece based on image information obtained by photographing the workpiece. The relative position and orientation can also be determined based on reference information reflected in the image information. Reference information can be markings disposed on the workpiece, shape features of the workpiece, contour information, planar information, or a combination thereof. The determination of relative position and orientation can also be performed using geometric calculations based on the mounting position of the imaging device, the posture of the robot arm, and the image information. Alternatively, the coordinates of the workpiece in its workpiece coordinate system or at a specific location within the workpiece coordinate system can be determined based on the relative position and orientation. Markings can include one or more markers.

[0016] Invention Effects The heat transfer tube replacement method and heat transfer tube replacement device of the present invention can be easily used in the field. Attached Figure Description

[0017] Figure 1 This is a heat transfer tube replacement device for the implementation method.

[0018] Figure 2 yes Figure 1 View II.

[0019] Figure 3A Before tube expansion Figure 2 Section III-III.

[0020] Figure 3B It is after tube expansion Figure 2 Section III-III.

[0021] Figure 4 It is the control device for the heat transfer tube replacement device in the implementation method.

[0022] Figure 5 This is a list of pipe coordinates for the implementation method.

[0023] Figure 6 This is a flowchart illustrating the method for replacing the heat transfer tube in an embodiment.

[0024] Figure 7 This is a flowchart illustrating the method for creating a list of borehole coordinates for an implementation method.

[0025] Figure 8 This is a flowchart illustrating the pipe expansion method of the implementation method.

[0026] Symbol Explanation 1 Tube sheet, 6 Robot coordinate system, 11a Robot arm, 13 End effector, 35 3D camera, 43 CAD data, 45 Field of view, 47 Camera distance, 51 Tube sheet photo (tube sheet image), 53 Tube hole coordinates, 55 Tube hole coordinate list. Detailed Implementation

[0027] like Figure 1 As shown, the tube expansion device (heat transfer tube replacement device) 10 of the embodiment has a robot 11 and an end effector 13.

[0028] Robot 11 has a robot arm 11a, a coordinate origin 11b, and a flange 11c. Robot 11 is a multi-joint robot. The coordinate origin 11b is, for example, the intersection of the central axis of the first axis of robot 11 and the mounting surface. A coordinate system with the coordinate origin 11b as its origin is designated as robot coordinate system 6. Robot coordinate system 6 has a left-right direction (X direction), a front-back direction (Z direction), a up-down direction (Y direction), a rotation direction about the X direction (A direction), a rotation direction about the Y direction (B direction), and a rotation direction about the Z direction (C direction). The flange 11c is disposed at the front end of robot arm 11a.

[0029] The vector from flange 11c to the front end of tube expander 21 is set as vector 11d. The vector from flange 11c to 3D camera 35 is set as vector 11e.

[0030] The end effector 13 has a frame 15, a drive cylinder 17, a drive motor 19, a coupling 20, a pipe expander 21, a collar cylinder 33, a clamp 34, and a 3D camera 35.

[0031] The frame 15 is L-shaped and connected to the flange 11c. The drive cylinder 17 is connected to the frame 15. The drive cylinder 17 is a pneumatic cylinder. The drive cylinder 17 propels the drive motor 19 forward (in...). Figure 1 (From left to right) The expansion tool 21 is pushed out. The drive motor 19 is, for example, a servo motor. The drive motor 19 rotates the expansion tool 21. The drive motor 19 is connected to the drive cylinder 17. The coupling 20 detachably connects the expansion tool 21 to the drive motor 19. The collar cylinder 33 is connected to the drive motor 19. The collar cylinder 33 is connected to the clamp 34. The collar cylinder 33 causes the clamp 34 to move forward and backward in the front-to-back direction. The collar cylinder 33 can measure the amount of extension and retraction. The 3D camera 35 is connected to the drive motor 19.

[0032] The tube expander 21 has a mandrel 23, a collar 25, a rotating frame 27, multiple rollers 29, and a cover 24. The mandrel 23 extends in the front-rear direction and has a pointed conical shape. The collar 25 and the rotating frame 27 are hollow cylinders. The mandrel 23 passes through the collar 25 and the rotating frame 27. The collar 25 reciprocates along the mandrel 23 in the front-rear direction. The rotating frame 27 is supported by the collar 25 and is rotatable about the mandrel 23. The rotating frame 27 rotatably supports the rollers 29. The rollers 29 rotate about the mandrel 23. The cover 24 is disposed at the front end of the mandrel 23.

[0033] The clamping device 34 is, for example, a cylinder. The clamping device 34 clamps the collar 25. When the clamping device 34 clamps the collar 25, the collar cylinder 33 can cause the collar 25 to reciprocate in the front-rear direction.

[0034] like Figure 2 As shown, the heat exchanger 2 has a tube sheet 1 and a plurality of tubes (heat transfer tubes) 3. The tube sheet 1 has a plurality of tube holes 1a. The tubes 3 are inserted into the tube holes 1a respectively. The tube sheet 1 may have markings. The markings are, for example, two-dimensional markings.

[0035] The pipe expander 10 fixes the pipe 3 to the pipe sheet 1. (Refer to...) Figure 1 as well as Figure 8 Explain the steps of the action.

[0036] First, in step S5a, the clamp 34 releases the collar 25.

[0037] Next, in step S5b, the drive motor 19 rotates the spindle 23 forward via the coupling 20.

[0038] Next, in step S5c, the collar cylinder 33 advances the clamping device 34.

[0039] Next, in step S5d, the drive 19 stops the rotation of the spindle 23.

[0040] Next, in step S5e, the clamping device 34 clamps the collar 25.

[0041] Next, in step S5f, the collar cylinder 33 is released from its brakes. Thus, the clamping device 34 moves freely under external force.

[0042] Next, in step S5g, robot 11 inserts tube expander 21 into tube 3. When inserting tube expander 21 into tube 3, robot 11 moves only a predetermined amount of time and then stops.

[0043] In step S5h, the collar cylinder 33 monitors the position of the clamping device 34. When the collar cylinder 33 detects a change in the position of the clamping device 34 during the movement of the robot 11 (yes in step S5h), the robot 11 determines that the insertion of the tube expanding tool 21 has failed and returns to step S5g.

[0044] When the collar cylinder 33 does not detect a change in the position of the clamping device 34 during the movement of the robot 11 (no in step S5h), the robot 11 determines that the insertion of the tube expanding tool 21 is successful and proceeds to step S5j. In step S5j, the drive motor 19 causes the mandrel 23 to rotate clockwise again.

[0045] Next, in step S5k, the drive cylinder 17 propels the drive motor 19 forward. The spindle 23 then advances along with the drive motor 19. The roller 29 rotates together with the rotating frame 27. At this time, the collar 25 and the rotating frame 27 do not move axially. The spindle 23 self-propelled axially as it rotates. The roller 29 moves radially outward as the spindle 23 advances. Thus, the roller 29 expands and fixes the tube 3 into the tube hole 1a (see reference). Figure 3A , Figure 3B The collar cylinder 33 retracts as the drive motor 19 advances.

[0046] In step S5m, the drive unit 19 monitors the torque relative to time. If the torque of the drive unit 19 does not reach the predetermined value (no in step S5m), the drive unit 19 continues to monitor the torque relative to time. When the torque of the drive unit 19 reaches the predetermined value (yes in step S5m), the process proceeds to step S5p.

[0047] In step S5p, the drive motor 19 reverses the spindle 23. The collar cylinder 33 measures the amount of movement of the spindle 23 as the expansion stroke 55f.

[0048] Next, in step S5q, the drive cylinder 17 moves the drive motor 19 rearward.

[0049] Finally, in step S5r, robot 11 pulls tube expander 10 out of tube 3.

[0050] The 3D camera 35 has a pair of imaging elements 35a and a lens (not shown). The imaging range 81a is determined by the size of the imaging elements 35a, the field of view 45, the minimum imaging distance 47a, and the maximum imaging distance 47b. The 3D camera 35 is capable of capturing photographs or images of the tube sheet 1. The photographs or images captured by the 3D camera 35 contain positional information of the captured objects. It should be noted that the end effector 13 may have a 2D camera (not shown) instead of the 3D camera 35, or may have a 2D camera in addition to the 3D camera 35. Alternatively, the 3D camera 35 or the 2D camera may also be configured on the mounting surface of the robot 11.

[0051] like Figure 4As shown, the control device 39 includes a storage device 41, a computing device 65, an end effector control unit 77, and a robot control unit 78. The storage device 41, the computing device 65, the end effector control unit 77, and the robot control unit 78 are connected via a bus (not shown).

[0052] Storage device 41 can be a main storage device or an external storage device. Storage device 41 stores CAD data 43, field of view 45, camera distance 47, tube sheet photograph (tube sheet image) 51, tube coordinates 53, tube coordinate list 55, inspection photograph 56, acceptable range 57, camera program 58, tube expansion program 59, and tube expansion conditions 61. Alternatively, CAD data 43 can be omitted.

[0053] CAD data 43 is the CAD data for tube sheet 1. Preferably, CAD data 43 is 3D-CAD data. CAD data 43 may also include data for tube 3. CAD data 43 is associated with robot coordinate system 6.

[0054] like Figure 1 As shown, the field of view 45 is the field of view of the 3D camera 35. The imaging distance 47 includes a minimum imaging distance 47a. The imaging distance 47 may also include a maximum imaging distance 47b. The storage device 41 may also store the dimensions of the imaging element 35a (not shown).

[0055] Tube sheet photograph 51 is a photograph of the tube sheet 1 before diameter expansion. Multiple tube sheet photographs 51 may be included. The tube sheet 1 is not within the single photographic range 81a (see reference 81a). Figure 2 In the case of a tube sheet 1, the 3D camera 35 can divide the tube sheet 1 into multiple tube sheet photos 51 for taking pictures.

[0056] It should be noted that tube sheet photograph 51 can also be a photograph of tube sheet 1 taken before tube 3 is inserted. Tube sheet photograph 51 may also include marker images (not shown).

[0057] The borehole coordinates 53 are the center coordinates of the opening of borehole 1a, determined based on the tube sheet photograph 51. The borehole coordinates 53 include X coordinate 55b and Y coordinate 55c (see [reference]). Figure 5 The bore coordinates 53 are determined by the tube sheet coordinate system 4. The tube sheet coordinate system 4 is given by the offset of the coordinates (X, Y, Z, A, B, C) relative to the robot coordinate system 6. The bore coordinates 53 are obtained for each bore 1a photographed in the tube sheet image 51.

[0058] It should be noted that the pipe hole coordinate 53 can also be the center coordinate of pipe 3 determined based on the tube sheet photograph 51.

[0059] The bore coordinates 53 can also be determined using the robot coordinate system 6. In this case, the bore coordinate list 55 can also include the Z coordinate (mm) of bore 1a (not shown). The Z coordinate can be calculated as the intersection of the surface of tube sheet 1 and the central axis of bore 1a.

[0060] The borehole coordinate list 55 is created based on borehole coordinate 53. For example... Figure 5 As shown, the pipe coordinate list 55 stores the hole number 55a, X coordinate 55b, Y coordinate 55c, rotational speed 55d, torque 55e, expansion stroke 55f, judgment 55g, time 55h, cumulative torque 55j, enlarged diameter 55k, base diameter 55m, and increment 55n for each pipe hole 1a.

[0061] Hole number 55a indicates the construction sequence. Rotation speed 55d is the rotational speed of the drive motor 19 during pipe expansion. Torque 55e is the rotational torque of the drive motor 19 during pipe expansion. Pipe expansion stroke 55f is the amount of movement of the mandrel 23 during pipe expansion. Judgment 55g records whether the pipe expansion result is good (OK) or bad (NG). Time 55h is the time spent on pipe expansion. Cumulative torque 55j is the time-dependent integral value of the torque 55e during pipe expansion.

[0062] It should be noted that the borehole coordinate list 55 may also omit the borehole number 55a. In this case, the borehole coordinate list 55 stores a data set containing the X coordinate 55b and the Y coordinate 55c. The data sets can also be stored according to the construction sequence. Additionally, the foundation diameter 55m and the increment 55n can also be omitted.

[0063] like Figure 3B As shown, the enlarged diameter 55k is the inner diameter of the enlarged section 3a after expansion. The enlarged section 3a is the part expanded by roller 29, which is equivalent to the thickness range of the tube sheet 1. The base diameter 55m is the inner diameter of the non-expanded section 3b. The non-expanded section 3b is the part facing the tube sheet 1 further inward than the enlarged section 3a. The non-expanded section 3b is the part whose diameter change in the length direction is substantially zero. "Substantially zero" means that the difference between the diameter of the enlarged section 3a and the non-expanded section 3b is sufficiently small, and can be considered as the numerical range of the change in the diameter of the tube 3 itself. The base diameter 55m is equivalent to the inner diameter of the tube 3 before expansion. The increment 55n is the difference between the enlarged diameter 55k and the base diameter 55m.

[0064] It should be noted that the bore coordinate list 55 may also include Z coordinate, A coordinate, B coordinate, and C coordinate.

[0065] Additionally, the bore coordinate list 55 may also include the length (mm) of the protrusion of the tube 3 mounted on the bore 1a from the tube sheet 1.

[0066] Inspection photo 56 is a photograph of the tube sheet 1 after expansion. In the case of a large tube sheet 1, inspection photo 56 can be a group of multiple photos.

[0067] The acceptable range 57 is the threshold value used as the basis for determining whether a value is acceptable or unacceptable. The acceptable range 57 includes both a maximum and a minimum value. If the increment 55n is above the minimum value and below the maximum value, then 55g is considered acceptable. Otherwise, 55g is considered unacceptable.

[0068] It should be noted that the acceptable range of 57 can be used as a threshold relative to the enlarged diameter of 55k.

[0069] The camera program 58 is the operating program of the robot 11 used to take pictures of the tube sheet 1 by means of the 3D camera 35.

[0070] The pipe expansion program 59 is the operating program of the robot 11 used to expand the pipe 3 using the pipe expansion tool 21. The pipe expansion program 59 may also include the control program of the end effector 13. For hole number 55a that is determined to be qualified by 55g, the pipe expansion program 59 can skip the pipe expansion action.

[0071] It should be noted that the expansion procedure 59 can also perform expansion operations on all holes numbered 55a to be expanded.

[0072] The tube expansion condition 61 is the operating condition of the end effector 13. The tube expansion condition 61 includes, for example, the rotational speed of the drive motor 19 during delivery, the rotational speed during return, the rotational torque during tube expansion, the tool number, the tool diameter (neither shown), and the tube expansion stroke.

[0073] The arithmetic unit 65 includes a camera program creation unit 67, a borehole coordinate list creation unit 69, an evaluation unit 71, and a pipe expansion program creation unit 73. It should be noted that the camera program creation unit 67 and the evaluation unit 71 may be omitted.

[0074] The camera program creation unit 67 includes a camera coordinate determination unit 67a. (See reference...) Figure 2The camera coordinate determination unit 67a extracts the height 85 and width 83 of the configuration area 84 with the pipe holes 1a from the CAD data 43. Based on the working range of the robot 11 (not shown), the field of view 45, the camera distance 47, and the vector 11e, the camera coordinate determination unit 67a determines the dimensions (horizontal 82a × vertical 82b) of the camera range 81a of the tube sheet 1. Then, the camera coordinate determination unit 67a divides the configuration area 84 into multiple camera ranges 81a to 81h. For example, the camera coordinate determination unit 67a divides the width 83 by the horizontal 82a to determine the number of photos taken in the horizontal direction (X direction). The camera coordinate determination unit 67a divides the height 85 by the vertical 82b to determine the number of photos taken in the vertical direction (Y direction). Preferably, the camera ranges 81a to 81h are determined by repeating the pipe holes 1a at the boundary portions of the camera ranges 81a to 81h.

[0075] The camera coordinate determination unit 67a calculates the camera coordinates (not shown) of the robot 11 for taking pictures of the camera range 81a to 81h based on CAD data 43 and vector 11e. The camera program creation unit 67 connects the determined camera coordinates to generate the operation path (not shown) of the robot 11. Then, the camera program creation unit 67 creates the camera program 58 of the robot 11 based on the operation path.

[0076] The borehole coordinate list creation unit 69 includes a borehole coordinate determination unit 69a, a duplicate deletion unit 69b, and a construction sequence determination unit 69c. (See reference...) Figure 2The bore coordinate determination unit 69a extracts the centers 3001, 3002, and 3003 of bore 1a within the bore plate photograph 51. Additionally, the bore coordinate determination unit 69a calculates the coordinates of the bore plate center 1b and the tilt of the bore plate 1 relative to the robot coordinate system 6. Then, the bore coordinate determination unit 69a determines the bore plate coordinate system 4 based on the coordinates of the bore plate center 1b and the tilt. The bore coordinate determination unit 69a can also determine the bore plate coordinate system 4 based on robot coordinates, vector 11e, and the marker image. The bore coordinate determination unit 69a determines the bore coordinates 53 based on the coordinates (not shown) of the centers 3001, 3002, and 3003 extracted from the bore plate photograph 51 and the coordinates (not shown) of the 3D camera 35 that took the photograph. Here, the coordinates of centers 3001, 3002, and 3003 are either the center of bore 1a or the center of the bore 3. The coordinates of the 3D camera 35 are given by the sum of the coordinates of the flange 11c of the robot 11 and vector 11e. The coordinates of the 3D camera 35 are the coordinates in the robot coordinate system 6. The borehole coordinates 53 include X coordinate 55b and Y coordinate 55c. There are boreholes 1a1 that are repeatedly photographed in multiple tube sheet images 51. Therefore, the borehole coordinates 53 repeatedly include the coordinates of borehole 1a1. The duplicate deletion unit 69b deletes the duplicate borehole coordinates 53. The construction sequence determination unit 69c sorts the borehole coordinates 53 after deleting the duplicates using X coordinate 55b and Y coordinate 55c, and assigns a construction sequence, i.e., borehole number 55a. The borehole coordinate list creation unit 69 creates a borehole coordinate list 55 based on the borehole number 55a, X coordinate 55b, and Y coordinate 55c.

[0077] The evaluation unit 71 includes a diameter calculation unit 71a. (See reference...) Figure 3B , Figure 5 The diameter calculation unit 71a calculates the enlarged diameter 55k and the base diameter 55m for each borehole 1a based on the inspection photograph 56. The evaluation unit 71 calculates the increment 55n. The evaluation unit 71 compares the increment 55n with the acceptable range 57 and saves the judgment result in the judgment 55g. The evaluation unit 71 saves the enlarged diameter 55k and the base diameter 55m in the borehole coordinate list 55. It should be noted that the evaluation unit 71 can also make a judgment by comparing the enlarged diameter 55k with the acceptable range 57.

[0078] The tube expansion program creation unit 73 generates the trajectory (not shown) of the robot 11 during tube expansion based on the tube sheet photograph 51, the tube hole coordinate list 55, the tube expansion conditions 61, and the vector 11d. The tube expansion program creation unit 73 then creates a tube expansion program 59 based on the trajectory. Preferably, the tube expansion program creation unit 73 calculates the position and inclination of the tube sheet 1 based on the tube sheet photograph 51 or the tube hole coordinate list 55. Furthermore, the tube expansion program creation unit 73 creates the tube expansion program 59 based on the calculated position and inclination of the tube sheet 1.

[0079] It should be noted that the expansion procedure creation unit 73 can also extract the pipe hole 1a that is determined to be unqualified by 55g and create the expansion procedure 59.

[0080] The robot control unit 78 controls the robot 11 based on the camera program 58, the pipe expansion program 59, the pipe plate coordinate system 4, and the robot coordinate system 6. The robot control unit 78 controls the end effector 13 via the end effector control unit 77.

[0081] The end effector control unit 77 controls the drive cylinder 17, drive motor 19, collar cylinder 33, clamping device 34, and 3D camera 35. During pipe reaming operations, the end effector control unit 77 measures the rotational speed 55d, torque 55e, reaming stroke 55f, time 55h, and cumulative torque 55j. The end effector control unit 77 stores the rotational speed 55d, torque 55e, reaming stroke 55f, time 55h, and cumulative torque 55j in the pipe coordinate list 55.

[0082] according to Figure 6 Explain the pipe expansion method.

[0083] First, in step S1, the camera program creation unit 67 creates the camera program 58.

[0084] Next, in step S2, the robot control unit 78 operates the robot 11 according to the camera program 58 and takes a picture of the tube sheet 51 through the 3D camera 35.

[0085] Next, in step S3, the borehole coordinate list creation unit 69 creates a borehole coordinate list 55.

[0086] Next, in step S4, the tube expansion program creation unit 73 creates the tube expansion program 59.

[0087] Next, in step S5, the robot control unit 78 operates the robot 11 according to the pipe expansion procedure 59, expanding the pipe 3 using the pipe expansion tool 21. The robot control unit 78 records the pipe expansion operation results (rotation speed 55d, torque 55e, expansion stroke 55f, time 55h, and cumulative torque 55j) in association with the hole number 55a. The pipe expansion operation results can be rewritten for each pipe expansion operation. For qualified hole number 55a, the pipe expansion operation is skipped.

[0088] Next, in step S6, the robot control unit 78 operates the robot 11 according to the camera program 58 and takes inspection photos 56 through the 3D camera 35.

[0089] Next, in step S7, the evaluation unit 71 calculates the enlarged diameter 55k, the base diameter 55m, and the increment 55n based on the inspection photograph 56. The evaluation unit 71 records the enlarged diameter 55k, the base diameter 55m, and the increment 55n in association with the hole number 55a. Then, the evaluation unit 71 makes a judgment based on the acceptable range 57.

[0090] Next, in step S8, the evaluation unit 71 extracts the hole number 55a that is defective.

[0091] Next, in step S9, the evaluation unit 71 determines whether all hole numbers 55a are qualified. If all hole numbers 55a are qualified (yes in step S9), the process ends. Otherwise (no in step S9), the process returns to step S5.

[0092] It should be noted that steps S1, S8, and S9 can also be omitted.

[0093] Alternatively, in step S5, the expansion operation for the qualified hole number 55a can be skipped, and the expansion program creation unit 73 can extract only the unqualified hole number 55a and recreate the expansion program 59. At this time, the robot control unit 78 performs the expansion operation based on the new expansion program 59.

[0094] according to Figure 7 Explain step S3.

[0095] First, in step S3a, the borehole coordinate determination unit 69a determines the borehole coordinates 53 based on the tube sheet photograph 51.

[0096] Next, in step S3b, the duplicate deletion unit 69b deletes the duplicate pipe coordinates 53.

[0097] Next, in step S3c, the construction sequence determination unit 69c arranges the pipe hole coordinates 53 after deleting duplicate pipe hole coordinates 53 in the order of X coordinate 55b and Y coordinate 55c, and assigns them hole numbers 55a.

[0098] The tube expanding device 10 of this embodiment has a 3D camera 35, so the tube sheet photograph 51 contains the tilt information of the tube sheet 1. Therefore, the tilt of the tube sheet 1 relative to the robot coordinate system 6 and the position of the tube sheet 1 can be calculated based on the tube sheet photograph 51. Thus, without the operator performing a teaching operation, the tube expanding device 10 can expand all the tubes 3 inserted into the tube sheet 1.

[0099] There are instances where the position of the borehole 1a in the tube sheet 1 is inconsistent with the CAD data 43. According to the tube expansion method of this embodiment, the tube expansion program creation unit 73 creates a tube expansion program 59 based on the borehole coordinate list 55. Therefore, even if the number or position of the boreholes in the CAD data 43 differs from the actual number of boreholes in the tube sheet 1, the tube expansion program 59 will be created based on the actual condition of the tube sheet 1. Then, the tube expansion operation is performed in conjunction with the actual tube sheet 1.

[0100] According to the tube expansion method of this embodiment, after the tube expansion operation in step S5, an inspection photograph 56 is taken in step S6, and in step S7, it is determined whether the tube expansion operation was performed well. Then, the tube expansion operation in step S5 is performed again on the tube hole 1a with poor expansion. Therefore, the tube expansion operation can be performed without any omissions.

[0101] According to the tube expansion method of this embodiment, the tube expansion operation results are recorded for each tube hole 1a. Therefore, in the event of an abnormality in the heat exchanger 2, the operator can confirm the status of the tube expansion operation.

[0102] This invention is not limited to the embodiments described above. Various modifications can be made without departing from the spirit of this invention, and all technical matters encompassed by the technical ideas described in the claims are the subject of this invention. Although the embodiments shown are preferred examples, those skilled in the art can implement various alternatives, modifications, variations, or improvements based on the content disclosed in this specification, and these are included within the technical scope described in the appended claims.

Claims

1. A method for replacing a heat transfer tube, wherein, Based on the CAD data of the tube sheet with the tube holes for assembling heat transfer tubes, the field of view of the 3D camera, and the imaging distance, multiple camera coordinates are determined. These multiple camera coordinates are the coordinates of the robotic arm during the shooting process. The robotic arm moves the 3D camera to the camera coordinates and takes an image of the tube sheet at each camera coordinate. Determine the center coordinates of the heat transfer tube or the center coordinates of the tube hole, as reflected in the tube sheet image, i.e., the tube hole coordinates. Remove duplicate borehole coordinates and create a list of borehole coordinates. Assign the construction sequence, i.e., the hole number, to the center coordinates of the hole coordinate list. The robot arm expands the heat transfer tubes according to the hole numbering sequence through an end effector installed at the front end of the robot arm.

2. The method for replacing the heat transfer tube according to claim 1, wherein, Based on the tube sheet image, the position and tilt of the tube sheet relative to the robotic arm are determined. The robotic arm determines the coordinates of the tube hole in the tube sheet coordinate system, with the specific position of the tube sheet as a reference.

3. The method for replacing the heat transfer tube according to claim 1 or 2, wherein, The robotic arm moves to the camera coordinates and takes an inspection image of the expanded heat transfer tube at each camera coordinate. Each of the holes is numbered, and an enlargement diameter and a base diameter are determined. The enlargement diameter is the inner diameter of the enlarged section of the heat transfer tube, and the base diameter is the inner diameter of the non-enlarged section located inside the enlarged section when viewed from the tube sheet. The difference between the enlarged diameter and the base diameter is calculated as the increment. The increment is considered acceptable if it falls within a predetermined acceptable range, and unacceptable otherwise.

4. The method for replacing the heat transfer tube according to claim 3, wherein, Skipping the qualified hole numbers, the robotic arm expands the pipes in the order of the hole numbers using an end effector mounted at the front end of the robotic arm.

5. The method for replacing the heat transfer tube according to claim 3, wherein, The defective hole numbers are extracted and designated as defective numbers. The robot arm expands the heat transfer tube again through the tube expander end effector, according to the non-conforming numbers in ascending or descending order.

6. The method for replacing the heat transfer tube according to any one of claims 1 to 5, wherein, The rotational torque during tube expansion, the travel distance of the tube expansion tool (i.e., the tube expansion stroke), and the tube expansion time are measured and recorded in association with the hole number.

7. The method for replacing the heat transfer tube according to any one of claims 1 to 5, wherein, The rotational torque of the drive motor relative to the expander tube over time is measured. For each expanding tool mounted on the expanding end effector, the cumulative torque is calculated by accumulating the rotational torque relative to the elapsed time. A warning is issued when the accumulated torque reaches the predetermined life torque time.

8. A heat transfer tube replacement device, comprising: Robotic arm; An end effector, which is disposed at the front end of the robot arm and has a drive motor capable of assembling a pipe expander; A 3D camera is disposed at the front end of the robotic arm; as well as The control device includes a storage device, a computing device, and a robot arm control unit. The storage device stores: CAD data for the tube sheet; The field of view and shooting distance of the 3D camera; Tube sheet image; Pipe coordinates; List of borehole coordinates; and Hole number, The computing device has: The camera coordinate determination unit determines multiple camera coordinates based on the CAD data, the field of view, and the camera distance. These multiple camera coordinates are the coordinates of the 3D camera at the time of shooting. The tube hole coordinate determination unit determines the tilt of the tube plate relative to the robot coordinate system and the tube hole center coordinates (i.e., tube hole coordinates) of the tube plate as reflected on each tube plate image based on the tube plate image, and creates a tube hole coordinate list with duplicate tube hole coordinates deleted. The construction sequence determination unit assigns a construction sequence, i.e., a hole number, to the center coordinates of the borehole coordinate list; and The job program generation unit generates a pipe-expanding operation program for the robotic arm, based on the pipe hole coordinate list, for expanding the pipe by means of the end effector in sequence according to the hole number. The robot arm control unit drives the robot arm and the end effector based on the pipe expansion operation program.

9. A method for replacing a heat transfer tube, wherein, Based on the CAD data of the tube sheet with the tube holes for mounting heat transfer tubes, the field of view of the camera, and the camera distance, multiple camera coordinates are determined. These multiple camera coordinates are the coordinates of the robot arm during the shooting process. The robotic arm moves the camera to the camera coordinates and takes an image of the tube sheet at each camera coordinate. Determine the center coordinates of the heat transfer tube or the center coordinates of the tube hole, as reflected in the tube sheet image, i.e., the tube hole coordinates. Remove duplicate borehole coordinates and create a list of borehole coordinates including the construction sequence. The robot arm expands the heat transfer pipe according to the construction sequence using an end effector installed at the front end of the robot arm.

10. The method for replacing the heat transfer tube according to claim 9, wherein, The camera will take pictures of the correction marks configured on the tube sheet as marker images. The coordinate system of the tube sheet, i.e., the tube sheet coordinate system, is calculated based on the marking information representing the features of the correction markings, the position of feature points on the marking image, the posture of the robot arm, and the mounting position of the camera. Determine the coordinates of the tube hole in the tube sheet coordinate system.

11. The method for replacing the heat transfer tube according to claim 10, wherein, The camera includes at least one of a 2D camera and a 3D camera.

12. The method for replacing the heat transfer tube according to claim 10 or 11, wherein, The robotic arm determines the coordinates of the tube hole in the tube sheet coordinate system.

13. A heat transfer tube replacement device, comprising: Robotic arm; An end effector, which is disposed at the front end of the robot arm and has a drive motor capable of assembling a pipe expander; A camera, which is configured at the front end of the robotic arm; as well as The control device includes a storage device, a computing device, and a robot arm control unit. The storage device stores: The field of view and shooting distance of the camera; Tube sheet image; Pipe coordinates; and A list of borehole coordinates including the construction sequence. The computing device has: The tube hole coordinate determination unit determines the tilt of the tube plate relative to the robot coordinate system and the tube hole center coordinates (i.e., tube hole coordinates) of the tube plate as reflected on each tube plate image based on the tube plate image, and creates a tube hole coordinate list with duplicate tube hole coordinates deleted. A construction sequence determination unit assigns a construction sequence to the center coordinates of the borehole coordinate list; and The work program generation unit generates a pipe-expanding operation program for the robotic arm, based on the pipe coordinate list, for expanding the pipe using the end effector according to the construction sequence. The robot arm control unit drives the robot arm and the end effector based on the pipe expansion operation program.

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