JP2016132079A - Hole processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hole processing method capable of restraining damage of a trepanning tool.SOLUTION: A hole processing method of a member having a surface of including a first surface and a second surface of turning to the opposite direction of the first surface, includes a process of fixing the member so that the first surface is orthogonal to a horizontal plane, a process of contacting a blade and the first surface by arranging the blade of a trepanning tool in a first position, a process of moving the blade in the horizontal direction toward the second surface from the first surface while rotating the trepanning tool, a process of stopping the movement of the blade when the blade is arranged in a second position separate by a second distance shorter than a first distance between the first surface and the second surface from the first position, a process of retreating the trepanning tool from an annular ring-shaped groove formed in the member by the blade, a process of fixing the member so that the first surface becomes parallel to the horizontal plane by turning downward after retreating the trepanning tool and a process of separating a core arranged on the inside of the groove from the member by shaving at least a part of the second surface.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a hole drilling method.

  As a hole machining method, a trepanning method for forming a hole in a member using a trepanning tool as disclosed in Patent Document 1 is known. The trepanning tool includes a tube portion and a blade attached to the tip portion of the tube portion. A trepanning tool forms an annular groove in a member. When the blade of the trepanning tool penetrates the member, the core remains inside the groove. By removing the core, a large-diameter hole is formed in the member.

JP2013-107150A

  In the technical field related to the trepanning processing method, a vertical method for processing a member while moving a trepanning tool in a vertical direction and a horizontal method for processing a member while moving a trepanning tool in a horizontal direction are known. In the case of the vertical method, chips generated by processing may not be smoothly discharged from the groove. As a result, at least a portion of the trepanning tool can be damaged. In the case of the horizontal method, when the machining proceeds and the blade of the trepanning tool penetrates the member, the core may fall onto the trepanning tool. As a result, at least a portion of the trepanning tool can be damaged.

  The aspect of this invention aims at providing the drilling method which can suppress the damage of a trepanning tool.

  According to an aspect of the present invention, there is provided a hole drilling method for a member having a surface including a first surface and a second surface facing the opposite direction of the first surface, wherein the first surface is orthogonal to a horizontal plane. Fixing the member to the blade, placing the blade of the trepanning tool in the first position, bringing the blade into contact with the first surface, and rotating the trepanning tool while moving the blade to the first position. A step of moving in a horizontal direction from a surface toward the second surface, and a second position where the blade is separated from the first position by a second distance shorter than a first distance between the first surface and the second surface. A step of stopping the movement of the blade when disposed in the step, a step of retracting the trepanning tool from an annular groove formed in the member by the blade, and after retracting the trepanning tool, Front so that one side is facing downward and parallel to the horizontal plane And fixing the member, abrading at least a portion of said second surface, hole drilling method comprising the steps of separating the core being disposed inside the groove from the member.

  According to the aspect of the present invention, since the trepanning tool moves in the horizontal direction from the first surface side in a state where the member is fixed so that the first surface is orthogonal to the horizontal plane, chips are smoothly discharged from the groove. As a result, a groove is formed. The trepanning tool moves from the first position where the blade contacts the first surface to the second position in the horizontal direction. The second distance between the first position and the second position is shorter than the first distance between the first surface and the second surface. The blade stops at the second position without penetrating the member. In a state where the blade is stopped at the second position, the core does not fall and is connected to the member through the remaining portion. Before the blade penetrates the member, after the trepanning tool is retracted from the groove and the trepanning process is completed, the member is fixed so that the first surface faces downward and parallel to the horizontal plane. Since the first surface faces downward, the second surface facing the opposite direction of the first surface faces upward. With the second surface facing upward, at least a portion of the second surface is scraped and the remaining portion is removed, whereby the core disposed inside the groove is separated from the member. Thereby, the hole of a member is formed. In the trepanning process, chips are smoothly discharged from the groove. Further, in trepanning processing, the core does not fall. Therefore, damage to the trepanning tool is suppressed.

  In an aspect of the present invention, the method includes a step of forming an alignment through-hole connecting the first surface and the second surface before forming the groove, and the second surface is formed using the through-hole. The cutting position may be determined.

  Thereby, the remaining part is removed with high accuracy. As an alignment mark, a through-hole connecting the first surface and the second surface is used, so positioning processing when forming a groove from the first surface side using a trepanning tool, and positioning when cutting the second surface Both treatments are carried out using the same mark (through hole). Therefore, the remaining part is removed with high accuracy.

  The aspect of this invention WHEREIN: The said trepanning tool has a front-end | tip part, The cylinder part to which the said blade is attached to the said front-end | tip part, It arrange | positions inside the said cylinder part, and determines the position of the said cylinder part with respect to the said member And forming a pilot hole in which the positioning pin is disposed at a position determined with respect to the through hole on the first surface before forming the groove.

  Thereby, an annular groove is formed at a desired position with respect to the through hole which is the alignment mark.

  In the aspect of the present invention, the process of cutting the second surface may include a turning process in which a turning tool is applied to the second surface and moved while rotating the member.

  Thereby, the core and the member are separated while performing the surface processing of the second surface.

  In the aspect of the present invention, the cutting of the second surface includes a facing processing of selectively cutting a part of the second surface by applying a facing tool to the second surface in a state where the member is fixed. But you can.

  Thereby, the quantity by which a member is shaved is suppressed. Further, by chamfering the remaining portion, chamfering of the large-diameter hole to be formed is performed in parallel with the separation of the core and the member.

  According to the aspect of the present invention, a drilling method capable of suppressing damage to the trepanning tool is provided.

FIG. 1 is a longitudinal sectional view showing an example of a pressurized water reactor according to this embodiment. FIG. 2 is a perspective view showing an example of the upper core support plate according to the present embodiment. FIG. 3 is a perspective view showing an example of a flange portion of the upper core support plate according to the present embodiment. FIG. 4 is a perspective view showing an example of a trunk portion of the upper core support plate according to the present embodiment. FIG. 5 is a perspective view showing an example of a disk portion of the upper core support plate according to the present embodiment. FIG. 6 is a perspective view showing an example of the lower core support plate according to the present embodiment. FIG. 7 is a flowchart showing an example of the hole machining method according to the present embodiment. FIG. 8 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment. FIG. 9 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment. FIG. 10 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment. FIG. 11 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment. FIG. 12 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment. FIG. 13 is a schematic diagram for explaining an example of the hole machining method according to the present embodiment. FIG. 14 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment. FIG. 15 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment. FIG. 16 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment. FIG. 17 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment. FIG. 18 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment. FIG. 19 is a schematic diagram for explaining an example of the hole drilling method according to the present embodiment.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings, but the present invention is not limited thereto. The components of each embodiment described below can be combined as appropriate. Some components may not be used.

  FIG. 1 is a schematic configuration diagram illustrating an example of a nuclear power plant according to the present embodiment. FIG. 1 is a longitudinal sectional view showing an example of a pressurized water reactor 12 of a nuclear power plant according to this embodiment.

  The nuclear power plant has a nuclear reactor and a steam generator disposed in a nuclear reactor containment vessel, and a steam turbine power generation facility. The nuclear reactor according to the present embodiment uses light water as a reactor coolant and a neutron moderator, and generates high-temperature and high-pressure water that does not boil over the entire core, and generates steam by heat exchange by sending this high-temperature and high-pressure water to a steam generator. And a pressurized water reactor (PWR) that generates power by sending the steam to a turbine generator.

  The nuclear reactor heats the primary cooling water by fuel fission, and the steam generator exchanges heat between the high-temperature and high-pressure primary cooling water and the secondary cooling water to generate high-pressure steam. The steam turbine power generation facility generates power by driving the steam turbine with the steam. On the other hand, the steam that has driven the steam turbine is cooled by a condenser to become condensate, and is returned to the steam generator.

  As shown in FIG. 1, the reactor vessel 61 of the pressurized water reactor 12 includes a reactor vessel main body 62 and a reactor vessel lid (upper mirror) 63. A reactor vessel lid 63 is fixed to the reactor vessel body 62 by a plurality of bolt members 64 and nuts 65 so as to be opened and closed.

  The reactor vessel main body 62 has an inlet nozzle (inlet nozzle) 67 to which light water (coolant) as primary cooling water is supplied, and an outlet nozzle (exit nozzle) 68 for discharging light water. The reactor vessel main body 62 is fixed to a lower core support plate 70 disposed in the vicinity of the lower mirror 66. The upper core support plate 69 has a disk shape and has a plurality of holes 20. The upper core support plate 69 is connected to the upper core plate 72 via the core support rod 71. A reactor core 73 provided in the reactor vessel main body 62 is connected to an upper core plate 72 and a lower core plate 74. The lower core plate 74 is supported by the lower core support plate 70. The lower core support plate 70 is disk-shaped and has a plurality of holes.

  The core 75 includes an upper core plate 72, a core tank 73, and a lower core plate 74, and has a number of fuel assemblies 76 therein. A control rod 77 is disposed inside the core 75. The upper end portion of the control rod 77 becomes a control rod cluster 78 and is inserted into the fuel assembly 77. The upper core support plate 69 is fixed to the control rod cluster guide tube 79, and the control rod cluster guide tube 79 extends to the control rod cluster 78 in the fuel assembly 76.

  The reactor vessel lid 63 has a control jack drive device 80 of a magnetic jack, and is accommodated in a housing 81. The control rod drive unit 80 is connected to the control rod cluster 78, and controls the output of the nuclear reactor by moving the control rod cluster drive shaft 82 up and down with a magnetic jack.

  The reactor vessel main body 62 has an instrumentation nozzle 83. The instrumentation nozzle 83 is connected to the in-core instrumentation guide tube 84. Each in-core instrumentation guide tube 84 is connected to an upper and lower connecting plate 86 and a connecting plate 87 which are connected to the lower core support plate 70 and suppress vibrations.

  The control rod drive device 80 moves the control rod cluster drive shaft 82 to extract a predetermined amount of the control rod 77 from the fuel assembly 76, thereby controlling nuclear fission in the reactor core 75, and using the generated thermal energy, the reactor vessel 61 The light water filled therein is heated, and high-temperature light water is discharged from the outlet nozzle 68 and sent to the steam generator 13. On the other hand, by inserting the control rod 77 into the fuel assembly 76, the number of neutrons generated in the reactor core 75 is adjusted, and by inserting all the control rod 77 into the fuel assembly 76, the nuclear reactor is emergency Can be stopped.

  FIG. 2 is a perspective view showing an example of the upper core support plate 69 according to the present embodiment. As shown in FIG. 2, the upper core support plate 69 includes a flange portion 691, a body portion 692, and a disc portion 693. The flange portion 691, the body portion 692, and the disc portion 693 are connected by a welding process.

  FIG. 3 is a perspective view showing an example of the flange portion 691 of the upper core support plate 69 according to the present embodiment. As shown in FIG. 3, the flange portion 691 is an annular member.

  FIG. 4 is a perspective view showing an example of the trunk portion 692 of the upper core support plate 69 according to the present embodiment. As shown in FIG. 4, the body 692 is an annular member. The outer diameter of the trunk portion 692 is smaller than the outer diameter of the flange portion 691. In the present embodiment, the body 692 is formed by subjecting a rectangular member to skirt bending and longitudinal welding.

  FIG. 5 is a perspective view showing an example of the disk portion 693 of the upper core support plate 69 according to this embodiment. As shown in FIG. 5, the disc part 693 is a disc-shaped member. The disc part 693 has a plurality of large-diameter holes 20.

  FIG. 6 is a perspective view showing an example of the lower core support plate 70 according to the present embodiment. As shown in FIG. 6, the lower core support plate 70 is a disk-shaped member. The lower core support plate 70 has a plurality of large-diameter holes 30.

  In this embodiment, the hole 20 and the hole 30 are formed using a trepanning method. Hereinafter, an example of the processing method of the hole 20 according to the present embodiment will be described. The processing method of the hole 30 is substantially the same as the processing method of the hole 20. The description about the processing method of the hole 30 is simplified or omitted.

  FIG. 7 is a flowchart showing an example of a method for processing the hole 20 according to the present embodiment. As shown in FIG. 7, in this embodiment, the process (step which fixes the disc 10 so that the 1st surface 1 of the disc (member) 10 which is the raw material of the disc part 693 may be orthogonal to a horizontal surface (step). SP1), the process of forming the alignment through-hole 5 and pilot hole 4 in the disc 10 (step SP2), and the blade 202 of the trepanning tool 200 is disposed at the first position PJ1, and the blade 202 of the trepanning tool 200 The blade 202 is moved from the first surface 1 of the disk 10 to the second surface 2 of the disk 10 while rotating the trepanning tool 200 (step SP3). Processing to move horizontally (step SP4), processing to stop the movement of the blade 202 when the blade 202 is disposed at the second position PJ2 (step SP5), and the blade 202 to the disk 10 A process of pulling out the trepanning tool 200 from the formed annular groove 6 to retract the trepanning tool 200 (step SP6), and after retracting the trepanning tool 200, the first surface 1 of the disk 10 faces downward and is a horizontal plane. The process of fixing the disk 10 so as to be parallel to the surface (step SP7), the process of scraping at least a part of the second surface 2 (step SP8), and the core 7 arranged inside the groove 6 is a disk. 10 (step SP8) is performed.

  FIG. 8 is a perspective view showing an example of the disc 10 according to the present embodiment. The disc 10 is a material for the disc portion 693. The disc 10 has a surface. As shown in FIG. 8, the surface of the disk 10 is a first surface 1, a second surface 2 facing in the opposite direction of the first surface 1, and a third surface connecting the first surface 1 and the second surface 2. 3 is included. The first surface 1 may be referred to as the upper surface 1. The second surface 2 may be referred to as the lower surface 2. The third surface 3 may be referred to as a side surface 3.

  The outer shape of the first surface 1 is circular. The outer shape of the second surface 2 is circular. The first surface 1 is a flat surface. The second surface 2 is a flat surface. The first surface 1 and the second surface 2 are parallel. The external dimensions of the first surface 1 and the external dimensions of the second surface 2 are the same. That is, the first surface 1 and the second surface 2 are substantially congruent. The distance (first distance) between the first surface 1 and the second surface 2 is D. In the following description, the distance D between the first surface 1 and the second surface 2 is appropriately referred to as a thickness D.

  The disc 10 is fixed so that the first surface 1 is orthogonal to the horizontal plane (step SP1).

  FIG. 9 is a side view showing an example of a state in which the disc 10 is fixed. FIG. 10 is a front view showing an example of a state in which the disc 10 is fixed. As shown in FIG.9 and FIG.10, the disc 10 is fixed to the support apparatus 100 so that the 1st surface 1 may orthogonally cross with respect to a horizontal surface.

  The support device 100 includes a base member 101 fixed to the support surface 104, a surface plate 102 that supports the lower end portion of the disk 10, and a support member 103 that supports the third surface 3 of the disk 10. The support surface 104 includes, for example, a factory floor on which the support device 100 is installed. The support surface 104 is parallel to the horizontal plane.

  The support device 100 supports the disc 10 so that the first surface 1 and the second surface 2 of the disc 10 are orthogonal to the horizontal plane (support surface 104). The disc 10 is fixed to the support device 100 so that the first surface 1 and the second surface 2 are orthogonal to the horizontal plane. In the present embodiment, the surface plate 102 is disposed between the lower end portion of the disc 10 and the support surface 104. The support device 100 fixes the disc 10 in a state where the disc 10 and the support surface 104 are separated from each other. A plurality of support members 103 are arranged around the disk 10. The support member 103 supports the third surface 3 of the disk 10. The support member 103 may support a part of the first surface 1 of the disk 10 or a part of the second surface 2 of the disk 10. Thereby, the position of the disk 10 is fixed.

  The support device 100 fixes the disc 10 so that the first surface 1 and the second surface 2 of the disc 10 are inclined in the range of 70 [°] to 110 [°] with respect to the horizontal plane. Also good. That is, the disk 10 only needs to be supported by the support device 100 in a standing state.

  Next, the through hole 5 and the pilot hole 4 are formed in the disc 10 with the disc 10 supported by the support device 100 (step SP2). FIG. 11 is a diagram illustrating an example of the disk 10 in which the through hole 5 and the pilot hole 4 are formed. The through hole 5 is formed so as to connect the first surface 1 and the second surface 2. The through hole 5 functions as an alignment mark. The first surface 1 and the inner surface of the through hole 5 are orthogonal to each other. The second surface 2 and the inner surface of the through hole 5 are orthogonal to each other. That is, the through hole 5 is a straight hole orthogonal to the first surface 1 and the second surface 2. A penetration formed in the first surface 1 with respect to a predetermined reference point (for example, the center point of the first surface 1 or the center point of the second surface 2) in a plane parallel to the first surface 1 and the second surface 2. The position (relative position) of the opening (opening end) of the hole 5 matches the position (relative position) of the opening (opening end) of the through hole 5 formed in the second surface 2.

  A plurality of through holes 5 are provided around the center point of the first surface 1 (the center point of the second surface 2). In the present embodiment, at least four through holes 5 are provided around the center point of the first surface 1 (the center point of the second surface 2). Note that the number of through holes 5 may be three, or any number of five or more. The number of through holes 5 is smaller than the number of holes 20.

  The through hole 5 is formed at a predetermined position with respect to a predetermined reference point. That is, the relative position between the predetermined reference point and each of the plurality of through holes 5 is known data.

  The pilot hole 4 is formed in the first surface 1. The pilot hole 4 is a non-through hole. A plurality of pilot holes 4 are formed in the first surface 1. The number of pilot holes 4 is the same as the number of holes 20.

  The pilot hole 4 is formed at a predetermined position with respect to the through hole 5 on the first surface 1. That is, the relative positions of the through hole 5 and each of the plurality of pilot holes 4 are known data. The relative position between the predetermined reference position and each of the plurality of pilot holes 4 is known data.

  Next, trepanning is performed. The trepanning process is performed using a trepanning tool 200. FIG. 12 is a diagram illustrating an example of the trepanning tool 200 according to the present embodiment. As shown in FIG. 12, the trepanning tool 200 determines a position of the cylindrical portion 201 with respect to the disk 10 that is disposed inside the cylindrical portion 201 and has a distal end portion to which the blade 202 is attached. And a guide portion 203 having positioning pins 204 for the purpose.

  The cylinder part 201 is a cylindrical member. A blade 202 is disposed at the tip of the cylindrical portion 201. The disk 10 is processed by the blade 202. The guide part 203 is disposed inside the cylinder part 201. The guide part 203 has a positioning pin 204 for determining the position of the cylinder part 201 (blade 202) with respect to the disc 10.

  The cylinder part 201 can rotate around the central axis AX. The blade 202 rotates around the central axis AX together with the cylindrical portion 201 by the rotation of the cylindrical portion 201. The positioning pin 204 is disposed on the central axis AX.

  As shown in FIG. 12, in this embodiment, the trepanning tool 200 is arranged in a space where the first surface 1 faces. The trepanning tool 200 is disposed so that the blade 202 and the first surface 1 of the disk 10 face each other. Trepanning is performed from the first surface 1 side. In the trepanning process, positioning pins 204 are arranged in the pilot holes 4. Thereby, the trepanning tool 200 is positioned with respect to the disc 10.

  When trepanning is started, the blade 202 of the trepanning tool 200 is placed at the first position PJ1 as shown in FIG. 12, and the blade 202 and the first surface 1 of the disk 10 are brought into contact (step SP3). In a state where the positioning pin 204 is disposed in the pilot hole 4, the blade 202 disposed at the first position PJ1 and the first surface 1 come into contact with each other.

  The first position PJ1 includes the position of the first surface 1 with respect to the direction orthogonal to the first surface 1. By arranging the blade 202 at the first position PJ1, the blade 202 and the first surface 1 come into contact with each other. In a state where the blade 202 is disposed at the first position PJ 1, the blade 10 is in contact with the first surface 1, but the disk 10 is not cut by the blade 202.

  FIG. 13 is a diagram illustrating an example of trepanning processing according to the present embodiment. As shown in FIG. 13, the blade 202 of the trepanning tool 200 moves in the horizontal direction from the first surface 1 toward the second surface 2 while the tube portion 201 of the trepanning tool 200 rotates (step SP4). In the present embodiment, the moving direction of the blade 202 is a direction orthogonal to the first surface 1. At least a part of the disk 10 is moved by the blade 202 moving in the direction (horizontal direction) orthogonal to the first surface 1 from the first surface 1 toward the second surface 2 while rotating about the central axis AX. Is cut by the blade 202 to form an annular groove 6 in the disk 10.

  In the present embodiment, as shown in FIG. 13, when the blade 202 is arranged from the first position PJ1 to the second position PJ2, the movement of the blade 202 is stopped (step SP5).

  The first position PJ1 and the second position PJ2 are positions related to a direction (horizontal direction) orthogonal to the first surface 1. The second position PJ2 is a position separated from the first position PJ1 by a distance (second distance) L in the horizontal direction. The distance L is shorter than the distance (thickness) D.

  That is, in the present embodiment, trepanning is performed so that the blade 202 does not penetrate the disk 10. By the trepanning process, the annular groove 6 is formed by a dimension (depth) of a distance L from the first surface 1.

  In the following description, a part of the disk 10 between the bottom surface of the groove 6 and the second surface 2 is appropriately referred to as a remaining portion 8.

  In the following description, a part of the disk 10 inside the annular groove 6 is appropriately referred to as a core 7. The core 7 is formed inside the cylinder part 201.

  With respect to the direction orthogonal to the first position 1, the dimension (thickness) of the remaining portion 8 is W. That is, in the present embodiment, a groove 6 having a depth L is formed in a disc 10 having a thickness D, and a remaining portion 8 having a thickness W is formed. The depth L is smaller than the thickness D. In the present embodiment, the thickness W of the remaining portion 8 is 0.1 [%] or more and 1.0 [%] or less of the thickness D of the disk 10.

  After the annular groove 6 is formed in the disc 10 by the blade 202 so that the remaining portion 8 is formed, the trepanning tool 200 is pulled out from the groove 6 and the trepanning tool 200 is retracted (step SP6). ).

  As described above, a plurality of pilot holes 4 are formed before the grooves 6 are formed. A plurality of grooves 6 are formed in the disk 10 while positioning the blade 202 using each of the plurality of pilot holes 4.

  FIG. 14 is a front view showing an example of the disc 10 after the trepanning process is completed. As shown in FIG. 14, a plurality of grooves 6 are formed on the first surface 1. Before the groove 6 is formed, a through hole 5 that functions as an alignment mark is provided. The relative position of the through hole 5 with respect to a predetermined reference point is determined (known). The relative position of the pilot hole 4 with respect to the through hole 5 is determined (known). The relative position of the groove 6 with respect to the pilot hole 4 is determined (known). Therefore, the relative position of the groove 6 with respect to the predetermined reference point and the through hole 5 in a plane parallel to the first surface 1 and the second surface 2 is known.

  After retracting the trepanning tool 200 from the groove 6, the member disk 10 is fixed so that the first surface 1 faces downward and parallel to the horizontal plane (step SP7).

  FIG. 15 is a side view showing an example of a state in which the member disk 10 is fixed. As shown in FIG. 15, the member 10 is fixed to the support device 300 so that the first surface 1 faces downward and is parallel to the horizontal plane.

  The support device 300 rotates the support member 301 around the rotation axis J1 and the support member 301 that supports the disk 10, the spacer 302 that is disposed between the support member 301 and the first surface 1 of the disk 10. Possible drive device 303. In the present embodiment, the rotation axis J <b> 1 of the support member 301 passes through the center of the first surface 1.

  With the disc 10 supported by the support device 300, at least a part of the second surface 2 is processed (step SP8). In the present embodiment, the processing of the second surface 2 includes cutting at least a part of the second surface 2.

  FIG. 16 is a diagram schematically illustrating an example of a process for cutting the second surface 2 according to the present embodiment. As shown in FIG. 16, in the present embodiment, the process of cutting the second surface 2 is performed by rotating the disk 10 supported by the support member 301 around the rotation axis J1 by the driving device 303. It includes a turning process in which a turning tool 400 is applied to two surfaces 2 and moved. The turning tool 400 moves in a radial direction with respect to the rotation axis J1 in a state where the disk 10 rotates about the rotation axis J1. Thereby, the 2nd surface 2 is turned uniformly. The remaining portion 8 is removed by turning the second surface 2.

  FIG. 17 is a diagram schematically illustrating an example of a state in which the remaining portion 8 has been removed by cutting the second surface 2. As shown in FIG. 17, the second surface 2 is processed and the remaining portion 8 is removed, whereby the core 7 disposed inside the groove 6 is separated from the member disk 10 (step SP9). . By removing the core 7 from the disk 10, a large-diameter hole 20 is formed in the disk 10. Thereby, the disc part 693 of the upper core support plate 69 having the holes 20 is manufactured.

  FIG. 18 is a diagram schematically illustrating another example of a method of processing at least a part of the second surface 2 in step SP8. In the example shown in FIG. 18, in the process of cutting the second surface 2, a part of the second surface 2 is selectively applied by applying a facing tool 500 to the second surface 2 while the disc 10 is fixed. Includes facing machining. The facing tool 500 includes a tool main body that rotates about a rotation axis J2 and a blade provided on the tool main body.

  The facing tool 500 selectively cuts a part of the second surface 2 so as to remove the remaining portion 8 while rotating around the rotation axis J2. As described above, the opening end of the through hole 5 is provided on the second surface 2. The through hole 5 functions as an alignment mark. At the time of facing processing, the groove 6 cannot be recognized from the second surface 2 side, but the position of the groove 6 in the plane parallel to the second surface 2 is specified by the through hole 5. As described above, the relative position of the groove 6 with respect to the predetermined reference point and the through hole 5 in a plane parallel to the first surface 1 and the second surface 2 is known. Therefore, the position of the remaining portion 8 between the bottom surface of the groove 6 and the second surface 2 is specified using the through hole 5. The position where the second surface 2 is cut with the facing tool 500 can be determined using the through hole 5 so that the remaining portion 8 is selectively removed.

  FIG. 19 is a diagram schematically illustrating an example of the disc 10 after the remaining portion 8 has been removed using the facing tool 500. As shown in FIG. 19, a part of the second surface 2 is processed and the remaining portion 8 is removed, whereby the core 7 disposed inside the groove 6 is separated from the disk 10. By removing the core 7 from the disk 10, a large-diameter hole 20 is formed in the disk 10. Thereby, the disc part 693 of the upper core support plate 69 having the holes 20 is manufactured.

  In the example shown in FIG. 19, the remaining portion 8 is selectively removed, and chamfering is performed by the facing tool 500. A chamfer 9 is formed at the boundary between the second surface 2 and the inner surface of the hole 20.

  As described above, according to the present embodiment, the trepanning tool 200 is moved horizontally from the first surface 1 side in a state where the member disk 10 is fixed so that the first surface 1 is orthogonal to the horizontal plane. Since it moves, in the trepanning process, the groove 6 is formed while the chips are smoothly discharged from the groove 6. The trepanning tool 200 moves from the first position PJ1 where the blade 202 contacts the first surface 1 to the second position PJ2 in the horizontal direction. The distance L between the first position PJ1 and the second position PJ2 is shorter than the distance (thickness) D between the first surface 1 and the second surface 2. The blade 202 does not pass through the member disk 10 and stops at the second position PJ2. In a state where the blade 202 is stopped at the second position PJ2, the core 7 does not fall and is connected to the member disk 10 via the remaining portion 8. Before the blade 202 penetrates the member disk 10, after the trepanning tool 200 is retracted from the groove 6 and the trepanning process is finished, the member disk 10 has the first surface 1 facing downward and parallel to the horizontal plane. To be fixed. Since the first surface 1 faces downward, the second surface 2 facing away from the first surface 1 faces upward. With the second surface 2 facing upward, at least a part of the second surface 2 is scraped and the remaining portion 8 is removed, whereby the core 7 disposed inside the groove 6 becomes a member disk. 10 is separated. Thereby, the hole 20 of the disk 10 (disk part 693) is formed. In the trepanning process, chips are smoothly discharged from the groove 6. Further, in the trepanning process, the core 7 is prevented from dropping. Therefore, damage to the trepanning tool 200 is suppressed.

  In the present embodiment, the through hole 5 that functions as an alignment mark is formed before the groove 6 is formed, and the position at which the second surface 2 is cut is determined using the through hole 5. Thereby, the remaining part 8 is removed with high accuracy. Both the positioning process when forming the groove 6 from the first surface 1 side using the trepanning tool 200 and the positioning process when cutting the second surface 2 are performed using the same mark (through hole 5). The Therefore, the remaining part 8 is removed with high accuracy.

  Further, in the present embodiment, the trepanning tool 200 includes a cylindrical portion 201 having a distal end portion and a blade 202 attached to the distal end portion, and a position of the cylindrical portion 201 with respect to the member disk 10 disposed inside the cylindrical portion 201. Positioning pins 204 for determining. Before the groove 6 is formed, the pilot hole 4 in which the positioning pin 204 is disposed is formed at a position determined with respect to the through hole 5 on the first surface 1. Thereby, an annular groove 6 is formed at a desired position with respect to the through hole 5 which is an alignment mark.

  In the present embodiment, as described with reference to FIGS. 16 and 17 and the like, the machining of the second surface 2 is performed by applying the turning tool 400 to the second surface 2 while rotating the member disk 10. It may include turning to move. Thereby, the core 7 and the member disk 10 can be separated while performing the surface processing of the second surface 2.

  In the present embodiment, as described with reference to FIGS. 18 and 19 and the like, the machining of the second surface 2 is performed by using the facing tool 500 on the second surface 2 while the member disk 10 is fixed. A facing process for selectively cutting a part of the second surface 2 may be included. Thereby, the amount by which the member disk 10 is shaved is suppressed. Further, by chamfering the remaining portion 8, the chamfering of the large-diameter hole 20 to be formed can be performed in parallel with the separation of the core 7 and the member disk 10.

1 First surface (upper surface)
2 Second surface (lower surface)
3 Third side (side)
4 Pilot hole 5 Through hole 6 Groove 7 Core 8 Remaining part 9 Chamfered part 10 Disc (member)
12 Pressurized water reactor 20 Hole 30 Hole 61 Reactor vessel 62 Reactor vessel body 63 Reactor vessel lid (upper mirror)
64 Stud bolt 65 Nut 66 Lower mirror 67 Inlet nozzle (inlet nozzle)
68 Outlet nozzle (exit nozzle)
69 Upper core support plate 70 Lower core support plate 71 Core support rod 72 Upper core plate 73 Core tank 74 Lower core plate 75 Core 76 Fuel assembly 77 Control rod 78 Control rod cluster 79 Control rod cluster guide tube 80 Control rod drive device 81 Housing 82 Control rod cluster drive shaft 83 Instrumentation nozzle 84 In-core instrumentation guide tube 86 Connection plate 87 Connection plate 100 Support device 101 Base member 102 Surface plate 103 Support member 104 Support surface (floor surface)
200 Trepanning Tool 201 Cylinder 202 Blade 203 Guide 204 Positioning Pin 300 Support Device 301 Support Member 302 Spacer 303 Drive Device 400 Turning Tool 500 Facing Tool 691 Flange 692 Body 693 Disk AX Center Axis J1 Rotation Axis J2 Rotation axis PJ1 First position PJ2 Second position

Claims (5)

A hole drilling method for a member having a surface including a first surface and a second surface facing a direction opposite to the first surface,
Fixing the member such that the first surface is orthogonal to a horizontal plane;
Placing the blade of the trepanning tool in a first position and bringing the blade into contact with the first surface;
Moving the blade horizontally from the first surface toward the second surface while rotating the trepanning tool;
Stopping the movement of the blade when the blade is disposed at a second position away from the first position by a second distance shorter than a first distance between the first surface and the second surface;
Retreating the trepanning tool from an annular groove formed in the member by the blade;
After retreating the trepanning tool, fixing the member so that the first surface faces downward and parallel to the horizontal plane;
Scraping at least a portion of the second surface to separate the core disposed inside the groove from the member;
Drilling method including Forming a through hole for alignment connecting the first surface and the second surface before forming the groove,
Using the through hole to determine the position to cut the second surface;
The drilling method according to claim 1. The trepanning tool has a tip portion and a cylindrical portion to which the blade is attached to the tip portion;
A positioning pin disposed on the inside of the cylindrical portion for determining the position of the cylindrical portion with respect to the member;
Forming a pilot hole in which the positioning pin is disposed at a position determined with respect to the through hole on the first surface before forming the groove;
The hole processing method according to claim 2. The process of cutting the second surface includes a turning process of moving the member by applying a turning tool to the second surface while rotating the member.
The hole drilling method according to any one of claims 1 to 3. The processing for cutting the second surface includes facing processing for selectively cutting a part of the second surface by applying a facing tool to the second surface in a state where the member is fixed.
The hole drilling method according to any one of claims 1 to 4.

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