Patent Publication Number: US-2022230349-A1

Title: Alignment method for use in plant

Description:
TECHNICAL FIELD 
     The present disclosure relates to an alignment method for use in a plant, of performing alignment of a target object being an installation target through use of 3D images in advance when a large-sized apparatus is to be installed on, for example, a construction site of the plant. 
     BACKGROUND ART 
     When a large-sized apparatus is to be installed on a construction site, the position and size of a bolt hole being a joining portion sometimes do not match those of a joining portion of an installation target object. In this case, an enormous amount of time is required for modifying the apparatus by, for example, expanding the bolt hole or changing the bolt hole into an elongated hole. 
     In order to reduce such unnecessary work, the apparatus is generally shipped after the joining portions are fitted to each other on trial in advance at a factory in which the apparatus is manufactured. Specifically, this trial fitting is work for confirming whether or not the installation target object can be fastened by inserting a bolt through the joining portions, and is called “trial fit up” or “trial assembly.” 
     CITATION LIST 
     Patent Literature 
     [PTL 1] JP 2012-68062 A 
     SUMMARY OF INVENTION 
     Technical Problem 
     However, an actual apparatus is used to perform such trial fitting as described above, and hence the work itself requires enormous time and labor when an installation target object is a large-sized apparatus. In addition, when the installation target object is located at a high place, construction machinery and scaffolding are required. Under such circumstances, there has been a problem in that the trial fitting leads to an increase in cost and extension in schedule. 
     As a method that does not cause such time and labor as described above, there is also known an alignment device for acquiring a photograph of a joining portion, for example, a bolt hole, and comparing image data with design information in advance to perform alignment (see, for example, Patent Literature 1). 
     However, when the design information is used as in the case of this alignment device, the design information does not include a tolerance, and hence it is difficult to perform accurate alignment. 
     An object of the present disclosure is to provide an alignment method for use in a plant, which is capable of easily and accurately aligning joining portions. 
     Solution to Problem 
     According to one embodiment of the present disclosure, there is provided an alignment method for use in a plant, of aligning a first target object and a second target object to be joined to each other, the alignment method including: an insertion step of inserting a first jig having a target marked on a head of the first jig into a first hole portion formed in the first target object, and inserting a second jig having a target marked on a head of the second jig into a second hole portion formed in the second target object; a photographing step of acquiring a plurality of images of the first target object in which the first jig has been inserted into the first hole portion, and acquiring a plurality of images of the second target object in which the second jig has been inserted into the second hole portion; an acquisition step of acquiring a first two-dimensional image data group being a plurality of pieces of two-dimensional image data on the first target object which are acquired in the photographing step, and acquiring a second two-dimensional image data group being a plurality of pieces of two-dimensional image data on the second target object which are acquired in the photographing step; a conversion step of converting the first two-dimensional image data group into first three-dimensional image data, and converting the second two-dimensional image data group into second three-dimensional image data; a designation step of designating the target serving as an origin in each of an image based on the first three-dimensional image data and an image based on the second three-dimensional image data; a setting step of setting three-dimensional coordinates with respect to the origin in the first three-dimensional image data and the second three-dimensional image data through use of information on the origin designated in the designation step; and a position examination step of examining positions of the corresponding targets in the first three-dimensional image data and the second three-dimensional image data. 
     In this manner, the pieces of two-dimensional image data are each converted into the three-dimensional image data in advance, and the positions are examined, to thereby be able to accurately grasp an error in center positions of the first hole portion and the second hole portion. Therefore, it is possible to easily and accurately align joining portions. 
     Further, the alignment method for use in a plant according to one embodiment of the present disclosure further includes a modification step of modifying at least one of the first hole portion or the second hole portion based on alignment information obtained in the position examination step. 
     That is, the positions are examined in advance through use of the three-dimensional image data, and hence it is possible to quickly modify only a required hole portion through use of the alignment information obtained in the position examination step (by, for example, expanding the hole portion or changing the hole portion into an elongated hole). 
     Further, the alignment method for use in a plant according to one embodiment of the present disclosure further includes: a shipping step of shipping the first target object and the second target object under a state in which the at least one of the first hole portion or the second hole portion has been modified in the modification step; and a joining step of joining the first target object and the second target object that have been shipped in the shipping step. 
     That is, the positions are examined in advance through use of the three-dimensional image data, and the target objects are shipped to a construction site under the state in which the hole portion has been modified. Therefore, it is not required to perform alignment work and modifying work at the construction site, and it is possible to easily and quickly perform assembling work at low cost. 
     In the alignment method for use in a plant according to one embodiment of the present disclosure, the first jig and the second jig are each a plug having an inverted truncated cone shape. 
     In this manner, it is preferred to use a plug having an inverted truncated cone shape as the jig used for the alignment. 
     Further, in the alignment method for use in a plant according to one embodiment of the present disclosure, a target object completed by joining the first target object and the second target object to each other is a large-sized apparatus for a plant. 
     In this manner, according to the alignment method for use in a plant of one embodiment of the present disclosure, when a large-sized apparatus for a plant is to undergo a joining process, it is no longer required to perform large-scale trial fitting work using, for example, construction machinery and scaffolding at a factory, to thereby be able to reduce a work load at the factory. 
     Advantageous Effects of Invention 
     According to the present disclosure, it is possible to provide the alignment method for use in a plant, which is capable of easily and accurately aligning the joining portions. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of a target object to be subjected to alignment through use of an alignment method for use in a plant according to an embodiment, as viewed from above. 
         FIG. 2  is a conceptual view for illustrating an example of production sites (for example, factories) and an assembly site (for example, a construction site) of the target object to be subjected to alignment through use of the alignment method for use in a plant according to the embodiment. 
         FIG. 3  is a block diagram for illustrating the structure of an alignment device for a plant in the embodiment. 
         FIG. 4  is a flow chart for illustrating processing involved in the alignment method for use in a plant according to the embodiment. 
         FIG. 5  are views for illustrating a jig (plug) to be used for joining target objects in the embodiment and joining portions into which jigs have been inserted, respectively. 
         FIG. 6  is a table for showing coordinates of targets displayed on a display unit of the alignment device for a plant in the embodiment. 
         FIG. 7  is a table for showing coordinates of targets displayed on a display unit of the alignment device for a plant in another embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Now, an alignment method for use in a plant according to an embodiment of the present disclosure is described with reference to the accompanying drawings.  FIG. 1  is a perspective view for illustrating a target object to be subjected to alignment through use of the alignment method for use in a plant according to the embodiment. In this case, a furnace frame of a combustion apparatus is illustrated as an example of a target object  2 . As illustrated in  FIG. 1 , the target object  2  is formed by joining a first target object  4  and a second target object  6 . 
     The first target object  4  and the second target object  6  each have a rectangular parallelepiped shape, and have flanges  8  and  10 , respectively, at edges of opening portions facing each other. First hole portions  12  and second hole portions  14  are formed in the flanges  8  and  10 , respectively, as bolt holes at predetermined intervals. In addition, a singular point  16  (for example, a QR code (trademark), a marker, a tiger rope, a bar code, character information, or a sphere) and a scale  18  are attached to each of outer surfaces of the first target object  4  and the second target object  6 . The singular point  16  and the scale  18  may be arranged in vicinities of the first target object  4  and the second target object  6  instead of being attached thereto so as to be photographed together with the first target object  4  and the second target object  6  at a time of photographing described later. 
       FIG. 2  is a conceptual view for illustrating an example of production sites (for example, factories) and an assembly site (for example, a construction site) of the target object  2 . As illustrated in  FIG. 2 , for example, the first target object  4  is manufactured at Factory A in Country X, the second target object  6  is manufactured at Factory B in Country X, and the first target object  4  and the second target object  6  are assembled at a plant construction site in Country Y, to thereby complete the target object  2 . In this case, an alignment device  20  for a plant in the embodiment is arranged in an office in Country Z. 
     Next, the alignment device  20  for a plant in the embodiment is described.  FIG. 3  is a block diagram for illustrating the structure of the alignment device  20  for a plant in the embodiment. The plant alignment device  20  is used for aligning the first target object  4  and the second target object  6  to be joined to each other. As illustrated in  FIG. 3 , the alignment device  20  for a plant includes a control unit  22  for controlling each unit, and the control unit  22  is connected to a communication unit  24  for communicating to/from a terminal  40  of Factory A and a terminal  42  of Factory B, a conversion unit  26  for converting a plurality of pieces of two-dimensional image data into one piece of three-dimensional image data, a storage unit  28  for storing the three-dimensional image data, a display unit  30  for displaying an image based on the three-dimensional image data, and an input unit  32  for inputting required information into the image displayed on the display unit  30 . Examples of the input unit  32  include a touch panel for inputting information by a touch operation. 
     Next, the alignment method for use in a plant in the embodiment, of performing processing for performing the alignment of the target object  2 , that is, aligning the first target object  4  and the second target object  6  to be joined to each other, is described with reference to a flow chart illustrated in  FIG. 4 . First, at Factory A, plugs  52  each of which is illustrated in  FIG. 5( a )  are provided. The plug  52  is an inverted-truncated-cone-shaped component having a larger diameter at a position closer to its head, and a target  52   a  is marked on the head. As illustrated in  FIG. 5( b ) , the plugs  52  are inserted into the first hole portions  12  formed in the flange  8  of the first target object  4  so that the targets  52   a  are positioned on a surface side of the flange  8 , which is opposite to its surface to be joined. Each plug  52 , which has a shape having a larger diameter at a position closer to the head, is inserted into the first hole portion  12  without a gap (insertion step, Step S 1 ). In the same manner, the plugs  52  are provided at Factory B, and inserted into the second hole portions  14  formed in the flange  10  of the second target object  6 . 
     Next, the first target object  4  is photographed through use of a camera  38  under a state in which the plugs  52  (first jigs) are inserted into the first hole portions  12  in the flange  8  (photographing step, Step S 2 ). The photographing is performed from various angles. As the camera  38 , for example, a digital camera or a smartphone is used. At Factory B, in the same manner as the first target object  4 , the second target object  6  is photographed through use of a camera  39  under a state in which the plugs  52  (second jigs) are inserted into the second hole portions  14  in the flange  10 . 
     At Factory A, a plurality of acquired images are recorded in the terminal  40  as a first two-dimensional image data group. At Factory B, a plurality of acquired images are recorded in the terminal  42  as a second two-dimensional image data group. Examples of the terminals  40  and  42  include a personal computer, and the recording of the first two-dimensional image data group and the second two-dimensional image data group into the terminal  40  is performed by replacing, for example, a memory card from the cameras  38  and  39  to the terminals  40  and  42 , respectively. Subsequently, the first two-dimensional image data group of the first target object  4  and the second two-dimensional image data group of the second target object  6 , which have been obtained through the photographing, are transmitted from the terminals  40  and  42 , respectively, to the alignment device  20  for a plant arranged in the office in Country Z by, for example, electronic mail. 
     When the control unit  22  receives (acquires) the first two-dimensional image data group through the communication unit (acquisition step, Step S 3 ), the control unit  22  controls the conversion unit  26  to convert the first two-dimensional image data group into one piece of first three-dimensional image data (conversion step, Step S 4 ). At a time of the conversion, respective first two-dimensional image data is joined to one another through use of the singular points  16  included in the first two-dimensional image data. In addition, scales of the respective two-dimensional image data are unified through use of the scale  18 . In the same manner, after the second two-dimensional image data group is received, the second two-dimensional image data group is converted into one piece of second three-dimensional image data. The conversion into the three-dimensional image data is performed through use of a publicly known technology. The first three-dimensional image data and the second three-dimensional image data are stored in the storage unit  28 . 
     Subsequently, the control unit  22  reads out the first three-dimensional image data and the second three-dimensional image data from the storage unit  28 , and displays images based on the respective three-dimensional image data on the display unit  30 , for example, side by side. The image may be displayed on the display unit  30  by an operator&#39;s own operation. In this case, while viewing the image of the first target object  4  and the image of the second target object  6  that are displayed on the display unit  30 , the operator designates the target  52   a  serving as the origin of each target object by, for example, a touch operation (designation step, Step S 5 ). After each origin is determined, the operator sets three-dimensional coordinate axes with respect to the origin in each piece of the first three-dimensional image data and the second three-dimensional image data (setting step, Step S 6 ). In this manner, the three-dimensional coordinate axes are set for each piece of the first three-dimensional image data and the second three-dimensional image data, to thereby enable objective recognition of center positions of each first hole portion  12  and each second hole portion  14 . 
     Subsequently, after the control unit  22  identifies the coordinates of each target  52   a  on the three-dimensional coordinate axes in the image based on each piece of three-dimensional image data, the control unit  22  may further display a table of the identified coordinates on the display unit  30  as shown in  FIG. 6 . The table of those and a pair of a first three-dimensional image and a second three-dimensional image may be displayed together, or only one thereof may be displayed. 
     Subsequently, while viewing the table of the coordinates, the first three-dimensional image, and the second three-dimensional image displayed on the display unit  30 , the operator aligns the corresponding targets  52   a  in the first three-dimensional image data and the second three-dimensional image data, that is, examines the coordinate positions of the corresponding targets  52   a  (position examination step, Step S 7 ). Subsequently, the operator grasps the targets  52   a  having corresponding coordinate positions falling out of an allowable error, and contacts a worker in charge of the first target object  4  by telephone or the like to notify the worker of the position of the first hole portion  12  in which one of the targets  52   a  having the corresponding coordinate positions falling out of the allowable error is arranged. In the same manner, the operator contacts a worker in charge of the second target object  6  by telephone or the like to notify the worker of the position of the second hole portion  14  in which the other one of the targets  52   a  having the corresponding coordinate positions falling out of the allowable error is arranged, as alignment information (contact step, Step S 8 ). 
     When the workers in charge are contacted, the workers modify the first hole portion  12  and the second hole portion  14  corresponding to the targets  52   a  that fall out of the allowable error based on the alignment information by, for example, expanding the first hole portion  12  and the second hole portion  14  or changing the first hole portion  12  and the second hole portion  14  into elongated holes, respectively (modification step, Step S 9 ). After the modification, the first target object  4  and the second target object  6  are shipped from Factory A and Factory B, respectively, to the construction site in Country Y (shipping step, Step S 10 ). When it is sufficient that the modification is performed on any one of the first target object  4  and the second target object  6 , any one of the first target object  4  and the second target object  6  is shipped without being modified. In this case, in the contact step (Step S 8 ), it is not required to contact a worker in charge of the target object  2  that is not required to be modified. 
     When a person in charge of the construction site in Country Y receives the first target object  4  and the second target object  6 , the person aligns the positions of each first hole portion  12  formed in the flange  8  of the first target object  4  and each second hole portion  14  formed in the flange  10  of the second target object  6 , and inserts a bolt through each first hole portion  12  and each second hole portion  14  to join the first target object and the second target object  6  (joining step, Step S 11 ), to thereby complete the target object  2 . 
     According to the alignment method for use in a plant of this embodiment, the first target object  4  in which the plug  52  having the target  52   a  marked on the head has been inserted into each first hole portion  12  and the second target object  6  in which the same plug  52  has been inserted into each second hole portion  14  are each photographed, the pieces of two-dimensional image data on the first target object  4  and the second target object  6  are each converted into three-dimensional image data, and the three-dimensional coordinate axes are set therefor, to thereby be able to accurately grasp an error in center positions of each first hole portion  12  and each second hole portion  14 . Therefore, the first target object  4  and the second target object  6  are shipped to the construction site after such an error is previously grasped and work for modifying this error is performed in advance at the factory, to thereby be able to easily and accurately align the joining portions of the first target object  4  and the second target object  6  at the construction site. 
     That is, according to the alignment method for use in a plant of this embodiment, the same effect as that of “trial fit up” can be obtained through use of the three-dimensional image data, and the alignment work is no longer required at the factory or the construction site. Therefore, the cost required for the alignment can be significantly reduced, and the schedule can be shortened. 
     In the above-mentioned embodiment, as illustrated in  FIG. 2 , the first target object  4  and the second target object  6  are located in Country X, the construction site is located in Country Y, and the alignment device  20  for a plant is located in Country Z, but those locations are not limited to different countries. For example, the first target object  4 , the second target object  6 , the alignment device  20  for a plant, and the construction site may be located in slightly distant places on the same site. In this case, the acquisition unit is not required to be the communication unit  24 , and may be, for example, connected to the cameras  38  and  39  or the terminals  40  and  42  in a wired manner. 
     Further, in the above-mentioned embodiment, the input unit  32  is not limited to the touch panel, and may be, for example, a mouse or a keyboard. In this case, the operator operates the mouse while viewing the display unit  30 , and uses a pointer to designate the target  52   a  as the origin. 
     Further, in the photographing step (Step S 2 ) in the above-mentioned embodiment, the first two-dimensional image data group and the second two-dimensional image data group after the photographing are not required to be stored in the terminals  40  and  42 , respectively. For example, a memory card or a CD in which the first two-dimensional image data group and the second two-dimensional image data group are recorded may be mailed to the office in Country Z. In this case, when, for example, the memory card or the CD is connected to the alignment device  20  for a plant on site, the first two-dimensional image data group and the second two-dimensional image data group are read into the alignment device  20  for a plant. In another case, the first two-dimensional image data group and the second two-dimensional image data group after the photographing may be directly transmitted from the cameras  38  and  39  to the alignment device  20  for a plant by, for example, electronic mail. 
     Further, in the setting step (Step S 6 ) for three-dimensional axes in the above-mentioned embodiment, the three-dimensional coordinate axes with respect to the origins are manually set, but the control unit  22  may use information on designated origins to set the three-dimensional coordinate axes with respect to the origins in the first three-dimensional image data and the second three-dimensional image data. 
     Further, in the position examination step (Step S 7 ) in the above-mentioned embodiment, the control unit  22  may determine whether or not an error in coordinates of each target  52   a  falls within an allowable error set in advance. For example, as shown in  FIG. 7 , the target  52   a  that falls within the allowable error is displayed by “0” or the like, and the target  52   a  that falls out of the allowable error is displayed by “x” or the like.  FIG. 7  shows an exemplary case in which an error of less than 0.04 falls within an allowable range. In addition, the allowable error can be freely set by, for example, the operator, and the set allowable error is stored in a storage unit (not shown). 
     Subsequently, when a predetermined notification operation is performed by the operator, the control unit  22  transmits the coordinates of the target  52   a  that falls out of the allowable error to the terminal  40  of Factory A and the terminal of Factory B as the alignment information through the communication unit  24  (contact step, Step S 8 ). Specifically, the notification is performed by transmitting the coordinates (5.05, 0, 0) in the first target object  4  and the corresponding coordinates (5.01, 0, 0) in the second target object  6  by, for example, electronic mail. 
     The terminals  40  and  42  that have received the notification inform a person in charge of managing the terminal  40  at Factory A and a person in charge of managing the terminal at Factory B, respectively, that the notifications of the coordinates have been received, by notification means, for example, alarms. The persons in charge who have received the informed notifications report details of the received notifications to the worker in charge of the first target object  4  and the worker in charge of the second target object  6 , respectively. 
     In this case, the information transmitted in the contact step is not limited to the coordinates of the target  52   a  that falls out of the allowable error, and the coordinates of the corresponding pair of targets  52   a  may be transmitted to the terminal  40  of Factory A and the terminal  42  of Factory B as the alignment information. 
     Further, in the above-mentioned embodiment, the plug  52  is used as the jig having the target  52   a  being displayed on the head, but as a jig other than the plug  52 , for example, a peg or a wedge may be used as the tool for the alignment. 
     REFERENCE SIGNS LIST 
     
         
           2  target object 
           4  first target object 
           6  second target object 
           8  first flange 
           10  second flange 
           12  first hole portion 
           14  second hole portion 
           16  singular point 
           18  scale 
           20  alignment device for plant 
           22  control unit 
           24  communication unit 
           26  conversion unit 
           28  storage unit 
           30  display unit 
           32  input unit 
           38  first camera 
           39  second camera 
           40  terminal 
           42  terminal 
           52  plug (jig) 
           52   a  target