JP6142557B2 - Work metal plate fixing device and work metal plate fixing method - Google Patents

Description

  The present invention relates to a workpiece metal plate fixing device and a workpiece metal plate fixing method.

  In a pressurized water nuclear power plant, primary cooling water heated in a nuclear reactor is supplied to a steam generator. In the steam generator, the secondary cooling water is heated by the heat of the primary cooling water to generate secondary steam. And this secondary steam is supplied to a steam turbine, a steam turbine is rotated, and a generator is driven. Such a steam generator is configured such that a cylindrical inner cylinder is accommodated in a cylindrical outer cylinder, and a number of inverted U-shaped heat transfer tubes are inserted into the inner cylinder. A disk-shaped tube support plate is provided to support (see, for example, Patent Document 1).

  In the manufacturing process of such a tube support plate, in order to form a large number of through holes through which the heat transfer tubes are inserted, the drilling process is performed on a metal plate having a diameter of several meters and a thickness of several tens of millimeters. Many through holes are formed. At that time, the required accuracy for the hole position is on the order of 0.1 mm, which is very severe. That is, the metal plate before drilling is not sufficiently removed from the distortion when processed into the plate shape having the diameter and thickness as described above, and, for example, a deformation (distortion) of about a dozen millimeters remains. In addition, since the metal plate is not regarded as a rigid body and bends and becomes like a spring, these hinder the precision machining of the metal plate (tube support plate).

Based on this background, conventionally, in order to satisfy the required accuracy for the above-described hole position, the hole-forming process is performed on the tube support plate by the following method.
First, a metal plate to be processed is arranged on a base of a drilling apparatus, and an outer peripheral portion thereof is fixed on the base.
Next, a positioning hole (positioning hole) is formed in the workpiece metal plate with the outer peripheral portion fixed on the base. At this time, the positioning hole is formed to have a smaller diameter than the through hole formed in the main processing. The base is formed with a female screw hole at a position corresponding to the positioning hole.

Next, a fixing bolt is inserted into the positioning hole of the metal plate to be processed, and this is screwed into a female screw hole of the base, thereby re-fixing the metal plate to be processed on the base. In this state, the outer peripheral portion of the metal plate to be processed is released.
Next, a large number of the above-described through holes are formed in the metal plate (perforating processing).
Thereafter, the fixing bolts inserted into the positioning holes are removed, and through holes having a larger diameter than the positioning holes are opened.

JP 2008-209063 A

  However, in the method for forming the through hole as described above, the fixing of the outer peripheral portion of the metal plate to be processed on the base, which is performed prior to the formation of the positioning hole, and the fixing bolt at the time of forming the through hole are performed. Because the fixing conditions are different from the fixing of the metal plate to be processed on the base, the through hole formed by re-perforating the positioning hole and the through hole formed by fixing with the fixing bolt In some cases, the axial deviation occurs and the required accuracy for the hole position is not satisfied.

That is, in the fixing at the time of forming the positioning hole, the fixing is performed in a state where the distortion remains in the metal plate to be processed. On the other hand, in the fixing of the metal plate by the fixing bolt, the distortion is almost from the metal plate to be processed. By fixing in the removed state, the positioning hole and the through hole that has been drilled in the state of being fixed by the fixing bolt are formed so that the positional relationship of the hole is deviated from the design, and the required accuracy is reduced. I was not satisfied.
Therefore, the positioning holes into which the fixing bolts are inserted are reworked so as to be in the proper hole positions when the holes are drilled again.
However, since such a series of processes is time-consuming, a lot of work time is required, and the productivity of the tube support plate is significantly reduced.

  The present invention has been made in view of the above circumstances, and its object is to fix a workpiece metal plate to be a tube support plate in order to facilitate drilling of the tube support plate and increase its productivity. It is an object of the present invention to provide an apparatus for fixing a workpiece metal plate and a method for fixing the workpiece metal plate which are facilitated.

The machined metal plate fixing device of the present invention is a machined metal plate fixing device used when forming a large number of through holes in a machined metal plate,
A base on which the metal plate to be processed is placed; and a spacer made of a magnetic material disposed between the base and the metal plate to be processed.
The base is provided with a fixing means for fixing the workpiece metal plate to the base via the spacer by the magnetic force of an electromagnet,
The electromagnet includes a center side magnet disposed on the base corresponding to at least a center portion of the workpiece metal plate, and an outer magnet disposed outside the center side magnet,
The electromagnet is energized to each of the center side magnet and the outer magnet, and when the work metal plate is fixed to the base, the center side magnet is energized to generate a magnetic force, A control unit that energizes the outer magnet to generate a magnetic force is connected.

In the fixing device for the metal plate to be processed, a guide for positioning and fixing the outer peripheral portion of the metal plate to be processed when the metal plate to be processed is fixed to the base via the spacer by the fixing means. It is preferable to have a member.
Further, in the fixing device for the metal plate to be processed, the metal plate to be processed becomes a tube support plate having a large number of through holes that are arranged inside the steam generator and through which the large number of heat transfer tubes are inserted. It is preferable.

The fixing method of the metal plate to be processed according to the present invention is a fixing method of the metal plate to be processed when a large number of through holes are formed in the metal plate to be processed,
A base on which the metal plate to be processed is placed; and a spacer made of a magnetic material disposed between the base and the metal plate to be processed. A fixing means for fixing the workpiece metal plate to the base via the center magnet, the electromagnet being disposed on the base corresponding to at least a center portion of the workpiece metal plate, Using a fixing device having an outer magnet disposed outside the central magnet,
Placing the metal plate to be processed on the base via the spacer;
A step of energizing the center side magnet of the electromagnet to generate a magnetic force, and fixing a center portion of the metal plate to be processed;
A step of energizing the outer magnet to generate a magnetic force while fixing the central portion of the metal plate to be processed, and fixing the outer portion from the central portion of the metal plate to be processed. .

In the fixing method of the metal plate to be processed, the outer peripheral portion of the metal plate to be processed is positioned and fixed on the spacer by a guide member after the step of fixing the outside of the center portion of the metal plate to be processed. It is preferable to have a process.
Further, in the method of fixing the metal plate to be processed, the metal plate to be processed becomes a tube support plate having a large number of through-holes that are arranged inside the steam generator and into which a large number of heat transfer tubes are inserted. It is preferable.

  According to the present invention, the metal plate to be processed is fixed to the base via the spacer by the fixing means provided on the base, so that the magnetic force of the electromagnet can be used without using a fixing bolt or the like as in the prior art. The metal plate to be processed can be fixed to the base very easily. In addition, since it is fixed via the spacer, if the through hole is formed in the metal plate to be processed by the drilling device in this fixed state, the metal plate can be processed without making a hole in the base. A through hole can be formed. Therefore, it is possible to facilitate the drilling of the workpiece metal plate and increase the productivity.

  Furthermore, the central magnet is energized to generate magnetic force, and after fixing the central portion of the metal plate to be processed, the outer magnet is energized to generate magnetic force while maintaining the central portion of the metal plate to be processed. Since the outer side is fixed from the center part of the plate, even if distortion (deformation) remains in the metal plate to be processed, the process of fixing by expanding the fixing of the metal plate to the outside from the central portion The distortion can be removed, and the entire workpiece metal plate can be fixed in that state. Therefore, it is possible to prevent the position of the through hole formed due to distortion or the bending of the metal plate to be processed from being deviated from the design and failing to satisfy the required accuracy.

It is a schematic diagram which shows schematic structure of 1st Embodiment of the fixing device of the metal plate to be processed based on this invention, (a) is sectional side view, (b) is a principal part enlarged view of (a). It is a perspective view which shows schematic structure of a steam generator. (A) is a plan view for explaining an example of the arrangement of electromagnets, (b) is a plan view for explaining another example of the arrangement of electromagnets, and (c) explains yet another example of the arrangement of electromagnets. It is a top view for doing. It is a figure which shows 2nd Embodiment of the fixing device of this invention, (a) is a top view of the to-be-processed metal plate in the fixed state, (b) is a side view of the fixing device which shows the state in the middle of fixing, (c ) Is a side view of the fixing device showing a state after fixing. It is explanatory drawing of the example which fixes a to-be-processed metal plate using a holding ring.

Hereinafter, with reference to the drawings, a metal plate fixing device and a metal plate fixing method of the present invention will be described in detail. In the following drawings, the scale of each member is appropriately changed to make each member a recognizable size.
FIG. 1 is a schematic diagram showing a schematic configuration of a first embodiment of a fixing device for a metal plate to be processed according to the present invention, wherein (a) is a side sectional view and (b) is an enlarged view of a main part of (a). is there.

In FIGS. 1A and 1B, reference numeral 1 denotes a fixing device for a metal plate to be processed. This fixing device 1 is used to manufacture a tube support plate that is disposed inside a steam generator that generates secondary steam by heating secondary cooling water by the heat of primary cooling water heated in a nuclear reactor. It is what
As shown in FIG. 2, the steam generator 2 is formed with a cylindrical body (inner cylinder) 3 having open ends, a large number of heat transfer tubes 4 having different sizes, and a large number of through holes 5. 5 and a plurality of tube support plates 6 for supporting the heat transfer tube 4 by inserting the heat transfer tube 4 therethrough.

The fixing device 1 shown in FIGS. 1 (a) and 1 (b) has a large number of through holes 5 through which the heat transfer tubes 4 are inserted in a metal plate 7 to be processed as a tube support plate 6 (see FIG. 2). It is used when doing. The metal plate 7 to be processed as the tube support plate 6 is formed of a magnetic material adsorbed by a magnetic force, such as ferritic stainless steel or martensitic stainless steel.
The fixing device 1 includes a base 8 on which the metal plate 7 to be processed is placed, and a spacer 9 made of a magnetic material disposed between the base 8 and the metal plate 7 to be processed. Has been.

  The base 8 is a quadrangular prism formed of a magnetic material having a high magnetic permeability such as metal or alloy, for example, ferritic stainless steel, martensitic stainless steel, silicon steel, permalloy or the like, that is, a rectangular mounting surface (upper surface). The surface has a fixing means 11 made up of a large number of electromagnets 10 on the surface layer (inside the surface). In the present embodiment, as shown in FIG. 3A, the electromagnet 10 constituting the fixing means 11 is an annular set (magnetic circuit) formed by alternately arranging N-pole magnets 10N and S-pole magnets 10S. A plurality of them are arranged concentrically.

  That is, in the present embodiment, the first group (magnetic circuit) 12a is arranged at the center of the rectangular upper surface 8a of the base 8, and the second group (magnetic circuit) 12b is disposed outside the first group. And a third group (magnetic circuit) 12c is arranged on the outer side. Although only the third group 12c is shown in FIG. 3A, the fourth group (magnetic circuit) is arranged outside the third group 12c, and the fifth group is arranged outside the third group 12c. More annular sets (magnetic circuits) may be formed and arranged, such as arranging (magnetic circuits).

  Here, the 1st group 12a arrange | positioned at the center part of the base 8 is arrange | positioned corresponding to the center part of the to-be-processed metal plate 7 mounted on the base 8 so that it may mention later. It functions as a center side magnet in the present invention. That is, the metal plate 7 to be processed is disposed on the spacer 9 so that the center portion thereof is positioned at the center portion of the base 8 as described later. Therefore, the first set 12a comes to face the central portion of the metal plate 7 to be processed, and thereby, the central portion of the metal plate 7 to be processed is sucked and fixed.

  Moreover, the 2nd group 12b, the 3rd group 12c, and also the group arrange | positioned on the outer side function as an outer magnet in this invention. That is, when the metal plate 7 to be processed is disposed on the base 8 via the spacer 9 as described above, when the first set 12a faces the center of the metal plate 7 to be processed, the second set 12b or The third set 12c comes to face outside from the center portion of the metal plate 7 to be processed, and as a result, the outside of the center portion of the metal plate 7 to be processed is sucked and fixed.

  The first set 12a to the third set 12c are connected to a control unit 13 that controls on / off of energization to the electromagnets 10N and 10S constituting the sets 12a to 12c. The control unit 13 is connected to a power source (not shown), and generates magnetic force for each group by performing on / off control of energization from the power source to the electromagnets 10N and 10S. In the present embodiment, the control unit 13 places the first metal plate 7 on the base 8 via the spacer 9 as will be described later, and then the first group corresponding to the central portion of the metal plate 7 to be processed. Energize 12a to generate magnetic force from the first set 12a, then energize the second set 12b to generate magnetic force from the second set 12b, and then energize the third set 12c Thus, a magnetic force is generated from the third set 12c.

  The control unit 13 is provided with a demagnetizing circuit. As will be described later, the demagnetization circuit energizes the first group 12a to the third group 12c to generate a magnetic force for each group, thereby forming the metal plate 7 (tube) after the through holes 5 are formed. The support plate 6) and the spacer 9 are demagnetized so as to return to the original non-magnetized state. Specifically, the first set 12a to the third set 12c are energized so that their polarities are opposite to those when energized at the time of fixing, and the generated magnetic force is gradually attenuated. The workpiece metal plate 7 (tube support plate 6) and the spacer 9 are demagnetized.

  As with the base 8, the spacer 9 is a rectangular plate formed of a magnetic material having a high magnetic permeability such as metal or alloy, such as ferritic stainless steel, martensitic stainless steel, silicon steel, permalloy, or the like. It is a disk-like one that is equal to or slightly larger than the processed metal plate 7. Since the spacer 9 is formed of a magnetic material having a high magnetic permeability as described above, the spacer 9 has a magnetic force from each set of electromagnets constituting the fixing means 11 of the base 8, that is, the first set 12a to the third set 12c. Is transmitted to the metal plate 7 to be processed, and the metal plate 7 to be processed is fixed to the base 8 by the magnetic force.

  Here, a large number of holes 14 may be formed in the spacer 9 corresponding to the through holes 5 formed in the metal plate 7 to be processed as shown in FIG. By forming the holes 14 in this way, when the drilling process is performed on the metal plate 7 to be processed, the spacer 9 is not damaged by the drill 15 penetrating the metal plate 7 to be processed. It can be reused. That is, it is possible to suppress the consumption of the spacer 9 and to reduce its cost.

Next, a fixing method using the fixing device 1 shown in FIGS. 1 (a) and 1 (b) will be described as an embodiment of the fixing method of the metal plate to be processed according to the present invention.
First, as shown in FIG. 1A, the metal plate 7 to be processed is placed on the base 8 via the spacer 9. At that time, for example, the X axis and the Y axis are written in advance on the base 8, the spacer 9, and the metal plate 7 to be processed by a gauge or the like, so that the center is drawn from the intersection. Then, the spacer 9 is placed on the base 8 with these X and Y axes aligned.

  At this time, the spacer 9 may be fixed to the base 8 using a fixing tool such as a bolt as required. Furthermore, the center of the base 8 and the center of the metal plate 7 are aligned by placing the metal plate 7 on the spacer 9 with the X-axis and the Y-axis aligned. As a result, the first set 12 a in the fixing means 11 provided on the base 8 comes to face the central portion of the workpiece metal plate 7.

  Next, the first set 12 a in the fixing means 11 is energized by operating the control unit 13. Then, in the 1st group 12a, as shown in Drawing 1 (b), magnetic field line 16 which passes along spacer 9 and processed metal plate 7 between adjacent N pole magnet 10N and S pole magnet 10S is produced, and magnetic force is generated. As a result, the metal plate 7 to be processed is fixed to the base 8 via the spacer 9. When the workpiece metal plate 7 is sucked and fixed in the first set 12a in this way, the center portion of the workpiece metal plate 7 is fixed by the first set 12a.

  Next, the control unit 13 is further operated to energize the second set 12b while maintaining the center portion of the metal plate 7 to be processed by the first set 12a. Then, in the second set 12b as well, the magnetic field lines 16 passing through the spacer 9 and the metal plate 7 to be processed are generated between the adjacent N-pole magnet 10N and S-pole magnet 10S in the same manner as the first set 12a. As a result, the metal plate 7 to be processed is fixed to the base 8 via the spacer 9. In this way, when the workpiece metal plate 7 is sucked and fixed also in the second set 12b, the center portion and the outside of the workpiece metal plate 7 are fixed by the first set 12a and the second set 12b. At that time, if the metal plate 7 is distorted (deformed) from the center portion to the outer side (corresponding) facing (corresponding to) the second set 12 b, this distortion is caused by the control unit 13. Removed by fixed control.

  That is, by fixing only the central portion first, the outer peripheral portion of the fixed portion is extended to some extent by the weight of the metal plate 7 to be processed, and the distortion (deformation) is corrected. And by being fixed by the 2nd group 12b in that state, the distortion from the center part to the position which opposes the 2nd group 12b from the center part is removed.

  Next, the control unit 13 is further operated to energize the third set 12c while maintaining the fixation of the metal plate 7 to be processed by the first set 12a and the second set 12b. Then, even in the third set 12c, the lines of magnetic force passing through the spacer 9 and the workpiece metal plate 7 between the adjacent N-pole magnet 10N and S-pole magnet 10S in the same manner as the first set 12a and the second set 12b. 16 to generate a magnetic force, thereby fixing the workpiece metal plate 7 to the base 8 via the spacer 9. When the metal plate 7 to be processed is sucked and fixed in the third set 12c in this way, the center portion and the outside of the metal plate 7 are moved by the first set 12a, the second set 12b, and the third set 12c. Fixed. At that time, as in the case of fixing with the second set 12b, the metal plate 7 to be processed was distorted (deformed) from the position facing (corresponding to) the second set 12b to the outside thereof (there remained). ), The distortion is removed by the fixed control by the control unit 13 described above.

  In this way, when the metal plate 7 to be processed is attracted and fixed by the set of all the electromagnets 10, and almost the entire surface thereof is fixed by the fixing means 11 by the electromagnet 10, the workpiece 15 is processed by the drill 15 as shown in FIG. A necessary number of through holes 5 are formed in the metal plate 7. Thereby, the metal plate 7 to be processed in which the desired number of through holes 5 are formed, that is, the tube support plate 6 is obtained.

  Thereafter, energization of the electromagnets 10 to the sets 12a to 12c by the control unit 13 is stopped, and the fixing of the metal plate 7 (tube support plate 6) to the base 8 is released. 7 (tube support plate 6) may remain magnetized, and therefore the metal plate 7 (tube support plate 6) is demagnetized by the demagnetization circuit of the control unit 13. That is, the demagnetization circuit is operated under the state where the workpiece metal plate 7 (tube support plate 6) is placed on the spacer 9, and each of the first set 12a to the third set 12c is fixed. At the same time, it is energized so that the polarity is opposite to that when it is energized, and the generated magnetic force is gradually attenuated.

  Thereby, the to-be-processed metal plate 7 (tube support plate 6) and the spacer 9 can be demagnetized. Therefore, the processed metal plate 7 (tube support plate 6) from which magnetism has been removed can be obtained. The tube support plate 6 (metal plate 7 to be processed) in which a large number of through-holes 5 are formed in this way is about half as heavy as before the through-holes 5 are formed, and the distortion ( (Deformation) is almost removed. Further, since the magnetism of the spacer 9 can be removed, the spacer 9 can be used as it is for the next drilling process of the metal plate 7 to be processed.

  According to the present embodiment, since the metal plate 7 to be processed is fixed to the base 8 via the spacer 9 by the fixing means 11 provided on the base 8, a fixing bolt or the like is used as in the prior art. In addition, the metal plate 7 to be processed can be fixed to the base 8 very easily by the magnetic force of the electromagnet 10. In addition, since the fixing is performed via the spacer 9, the through-hole 5 is formed in the processed metal plate 7 by the drill 15 in this fixed state, so that the processed metal plate 7 is not formed in the base 8 without making a hole. The through-hole 5 can be formed in. Therefore, it is possible to facilitate drilling of the workpiece metal plate 7 (tube support plate 6) and increase its productivity.

  Further, after energizing the first set 12a located on the center side to generate a magnetic force and fixing the center portion of the metal plate 7 to be processed, the second set 12b, while maintaining the center portion fixed, Furthermore, the third set 12c is energized to generate a magnetic force so that the outside of the center portion of the metal plate 7 is sequentially fixed, so that distortion (deformation) remains on the metal plate 7 to be processed. However, by expanding the fixing of the metal plate 7 to the outside from the central portion, distortion can be removed in the fixing process, and the entire metal plate 7 can be fixed in that state. Therefore, it is possible to prevent the position of the through-hole 5 to be formed due to distortion or bending of the workpiece metal plate 7 from being deviated from the design and failing to satisfy the required accuracy.

  In the embodiment, the arrangement of the electromagnets 10 constituting the fixing means 11 is an annular shape in which N-pole magnets 10N and S-pole magnets 10S are alternately arranged as shown in FIG. A plurality of sets 12a to 12c are arranged concentrically, but the present invention is not limited to this. For example, as shown in FIG. The formed S-pole magnets may be arranged concentrically.

  That is, the first annular magnet 17a is disposed at the center of the base 8, and the second annular magnet 17b and the third annular magnet 17c are disposed outside the first annular magnet 17a. , 5th circular magnets are arranged. At this time, the annular magnets 17a to 17c are formed and arranged so that the annular magnets adjacent in the radial direction have different polarities. For example, when the first annular magnet 17a is formed of the N-pole magnet 10N, the second annular magnet 17b is formed of the S-pole magnet 10S, and the third annular magnet 17c is formed of the N-pole magnet 10N. . Moreover, these annular magnets 17a to 17c may be formed of a single electromagnet or a plurality of electromagnets.

  When such a configuration is adopted, the center side magnet in the present invention is constituted by the first annular magnet 17a and the second annular magnet 17b, and the outer magnet is constituted by the second annular magnet 17b. It is comprised with the 3rd ring magnet 17c. Therefore, when the control unit 13 energizes the fixing means 11 composed of these ring magnets, first, the control unit 13 energizes the first ring magnet 17a and the second ring magnet 17b to supply these first circle magnets. A magnetic force is generated between the ring magnet 17a and the second ring magnet 17b, and the central portion of the metal plate 7 to be processed is fixed by this magnetic force. Next, the third annular magnet 17c is energized while the energization of the first annular magnet 17a and the second annular magnet 17b is maintained. Thereby, a magnetic force is also generated between the second annular magnet 17b and the third annular magnet 17c, and the outside of the center portion of the metal plate 7 to be processed is fixed by this magnetic force.

Therefore, even in the example shown in FIG. 3B, the same effect as the example shown in FIG. 3A can be obtained.
In addition, about the annular magnets 17a-17c, it does not become a continuous annular | circular shape, The some circular arc-shaped electromagnet which has the same polarity may be arrange | positioned circularly at predetermined intervals, and may be comprised. Furthermore, a plurality of rectangular or circular electromagnets having the same polarity may be configured by being arranged in an annular shape at a predetermined interval.

  In addition to the arrangement of the electromagnets shown in FIGS. 3A and 3B, for example, as shown in FIG. 3C, the N-pole magnet 10N and the S-pole magnet 10S are arranged vertically and horizontally. In addition, the N-pole magnets 10N and the S-pole magnets 10S may be alternately arranged in the column and the row. In FIG. 3C, in order to simplify the illustration, each of the vertical and horizontal portions is composed of five electromagnets (10N, 10S), but these numbers are based on the size of the metal plate 7 to be processed and each electromagnet ( 10N and 10S) can be appropriately changed. For example, the vertical and horizontal directions may be configured by 10 or more electromagnets (10N and 10S).

  When such a configuration is adopted, the center-side magnet in the present invention is configured by, for example, a first set 18a including an N-pole magnet 10N located at the center and four S-pole magnets 10S adjacent thereto. The Further, the outer magnets are, for example, a second set 18b composed of four N-pole magnets 10N arranged so as to sandwich the four S-pole magnets 10S constituting the first set 18a, and 16 located on the outermost periphery. The third set 18c is composed of electromagnets (eight N-pole magnets 10N and eight S-pole magnets 10S).

  Therefore, when energizing the fixing means 11 composed of these electromagnets, the control unit 13 first energizes the first group 18a corresponding to the central portion of the metal plate 7 to be processed and is located at the center of the N-pole magnet. A magnetic force is generated between 10N and four S-pole magnets 10S adjacent thereto, and the central portion of the metal plate 7 to be processed is fixed by this magnetic force.

Next, the second set 18b is energized to generate a magnetic force between the four N-pole magnets 10N and the four S-pole magnets 10S of the first set 18a sandwiched between them. The outside is fixed from the center of the metal plate 7 to be processed.
Thereafter, the third set 18c is energized to generate a magnetic force between the N-pole magnet 10N and the S-pole magnet 10S constituting the third set 18c, and each electromagnet constituting the third set 18c. And the electromagnets constituting the first set 18a and the second set 18b generate a magnetic force to fix the outer side of the metal plate 7 to be processed.

Therefore, even in the example shown in FIG. 3C, the same effect as the example shown in FIGS. 3A and 3B can be obtained.
In FIG. 3C, each of the electromagnets 10N and 10S is shown in a square shape in plan view. However, the shape of each of the electromagnets 10N and 10S is not limited to this, and may be other square shapes or circular shapes. May be. Moreover, these electromagnets 10N and 10S may be arranged so that adjacent ones are appropriately spaced.
Furthermore, the fixing means 11 in this embodiment is not limited to the arrangement of the electromagnets shown in FIGS. 3A to 3C, and various arrangements can be employed. For example, a plurality of (for example, eight) rows of electromagnets may be formed radially from the center, and the electromagnets constituting each row may be arranged so that the N-pole magnets 10N and the S-pole magnets 10S are alternately adjacent to each other. .

FIGS. 4A to 4C are views showing a second embodiment of the fixing device of the present invention, where FIG. 4A is a plan view of the metal plate to be processed in a fixed state, and FIG. The side view of the fixing device which shows a state, (c) is a side view of the fixing device which shows the state after fixing.
The fixing device 20 of the present embodiment is different from the fixing device 1 of the first embodiment in that, as shown in FIGS. 4A to 4C, a guide for fixing the metal plate 7 to be processed together with the fixing means 11. This is a point having the member 21.

  That is, the fixing device 20 of the present embodiment has a guide member 21 in addition to the fixing device 1 of the first embodiment. In this embodiment, the guide member 21 is composed of four guide bars 21a as shown in FIG. These four guide rods 21a are detachably fixed to the spacer 9 in this embodiment. For example, the four guide rods 21a are formed with male screws at the lower ends thereof, and these male screws are fixed to the spacer 9 by being screwed into female screws formed in the spacer 9 in advance.

  Moreover, in this embodiment, as shown to Fig.4 (a), the notch 7a of the plurality (four in this embodiment) is formed in the outer peripheral part of the to-be-processed metal plate 7. FIG. These notches 7a are formed in a V shape at equal intervals on the outer periphery of the disk-shaped metal plate 7 to be processed. That is, they are formed and arranged at four locations (four directions) where the X axis and Y axis passing through the center of the workpiece metal plate 7 and the outer periphery intersect. Here, as described above, distortion (deformation) remains on the workpiece metal plate 7 without being removed. However, the notch 7a is formed in four directions of the perfect circle assuming that there is no such distortion (deformation), that is, a perfect circle in design.

  On the other hand, the four guide bars 21a constituting the guide member 21 are disposed at positions corresponding to the four cutouts 7a when the metal plate 7 to be processed is regarded as a perfect circle. That is, the position of the female screw previously formed on the spacer 9 is formed so as to correspond to the four directions of the perfect circle, and therefore, by screwing to this, each guide bar 21a is placed in the four directions of the perfect circle. It is arranged at the corresponding position.

  In order to fix the metal plate 7 to be processed by the fixing device 20 having such a guide member 21, first, as shown in FIG. 4B, on the base 8 as in the first embodiment. The workpiece metal plate 7 is placed via the spacer 9. At that time, the notches 7a of the metal plate 7 to be processed are respectively engaged with the guide bars 21a. However, in this state, the metal plate 7 to be processed does not become a perfect circle due to the distortion, and therefore, the notches 7a engage with the guide bar 21a with a slight shift.

  Next, the control unit 13 is operated, and the fixing of the workpiece metal plate 7 is expanded from the center side to the outside by the fixing means 11 as in the first embodiment. When the metal plate 7 to be processed is fixed to the base 8 in this manner, the distortion (deformation) of the metal plate 7 to be processed is removed as described above. Therefore, the metal plate 7 to be processed becomes a perfect circle as designed as shown in FIG. 4C, and the four notches 7a engage with the guide bar 21a without being displaced. Accordingly, the outer peripheral portion of the metal plate 7 to be processed is more reliably positioned and fixed on the spacer 9 by the guide member 21.

  Thereafter, in the same manner as in the first embodiment, as shown in FIG. 1 (b), a drill 15 opens the required number of through-holes 5 in the metal plate 7 to form a desired number of through-holes 5. A metal plate 7, that is, a tube support plate 6 is obtained.

  In the present embodiment, since the outer peripheral portion of the metal plate 7 to be processed is positioned and fixed on the spacer 9 by the guide member 21, for example, in the circumferential direction of the metal plate 7 to be processed when the through hole 5 is formed. Even if such a force acts, the guide member 21 prevents the workpiece metal plate 7 from rotating about its axis, so that the displacement of the through hole 5 can be reliably prevented.

In the second embodiment, the notch 7a is formed directly in the metal plate 7 as shown in FIG. 4 (a). Instead, the retaining ring 22 as shown in FIG. 5 is used. May be used.
The holding ring 22 holds the outer peripheral surface of the metal plate 7 to be processed, and includes a pair of arc members 23 and 23 and a pair of connecting members 24 and 24 that connect the arc members 23 and 23. It is configured.

  The arc member 23 has an attachment portion 23a having holes (not shown) for attaching the connector 24 at both ends, and is formed in a substantially semicircular arc shape. These circular arc members 23, 23 have their mounting portions 23a opposed to each other, and the bolts of the connecting tool 24 consisting of bolts and nuts are inserted into the respective holes and fixed by the nuts, so that the inner peripheral surfaces thereof are true. It is comprised so that a circle may be formed.

In addition, a total of four V-shaped notches 25 are formed in each of the pair of arcuate members 23, two each. These notches 25 are respectively formed in four directions with respect to the perfect circle formed by the inner peripheral surfaces of the arc members 23 and 23 so as to correspond to the notches 7a of the metal plate 7 to be processed shown in FIG. Yes.
The guide member 21 shown in FIGS. 4A to 4C is a guide bar corresponding to the notch 25 formed in the holding ring 22 so as to fix the workpiece metal plate 7 via the holding ring 22. The position 21a is set. That is, it is fixed to the spacer 9 so as to correspond to the notch 25 of the retaining ring 22 and engage with it.

  In order to fix the workpiece metal plate 7 by the fixing device 20 using such a holding ring 22, first, the outer peripheral surface of the workpiece metal plate 7 is held by the holding ring 22 as shown in FIG. 5. Subsequently, the workpiece metal plate 7 held by the holding ring 22 is placed on the base 8 via the spacer 9 in the same manner as in the second embodiment. At that time, the notches 25 of the retaining ring 22 are respectively engaged with the guide rods 21a. Thereby, the holding ring 22 is positioned and fixed on the spacer 9 by the guide member 21.

  Next, the control unit 13 is operated, and the fixing of the workpiece metal plate 7 is expanded from the center side to the outside by the fixing means 11 in the same manner as in the first and second embodiments. When the metal plate 7 to be processed is fixed to the base 8 in this manner, the distortion (deformation) of the metal plate 7 to be processed is removed as described above. Therefore, the metal plate 7 to be processed becomes a perfect circle as designed, and fits exactly on the inner peripheral surface of the holding ring 22. As a result, the outer peripheral portion of the metal plate 7 to be processed is fixed in the holding ring 22 without rattling, and therefore, the metal plate 7 is surely positioned and fixed on the spacer 9 via the holding ring 22 and the guide member 21.

  Thereafter, in the same manner as in the first embodiment and the second embodiment, as shown in FIG. 1B, the drill 15 opens the necessary number of through holes 5 in the metal plate 7, and the desired number of through holes 5. The metal plate 7 to be processed, that is, the tube support plate 6 is obtained.

  Even in this embodiment, the outer peripheral portion of the metal plate 7 to be processed is positioned and fixed on the spacer 9 by the holding ring 22 and the guide member 21, so that, for example, the metal plate 7 to be processed is formed when the through hole 5 is formed. Even if a force is applied in the circumferential direction, the metal ring 7 is prevented from rotating around its axis by the holding ring 22 and the guide member 21, so that the displacement of the through-hole 5 is reliably prevented. can do.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.
For example, although the guide member 21 is provided on the spacer 9 in the second embodiment, it may be attached to the base 8 or may be provided on a member different from the spacer 9 or the base 8. Also good.
As for the configuration of the guide member 21, various configurations can be adopted in addition to the above-described four guide rods 21a as long as the outer peripheral portion of the workpiece metal plate 7 can be positioned and fixed.

  In the above embodiment, the metal plate to be processed is a tube support plate having a large number of through-holes, which is disposed inside the steam generator and allows a large number of heat transfer tubes to pass therethrough. The present invention is not limited to this, and can be applied to fixing all the metal plates to be processed as long as the metal plates are to be processed for forming a large number of through holes.

DESCRIPTION OF SYMBOLS 1 ... Fixing device, 2 ... Steam generator, 4 ... Heat transfer tube, 5 ... Through-hole, 6 ... Pipe support plate, 7 ... Metal plate to be processed, 8 ... Base, 9 ... Spacer, 10 ... Electromagnet, 10N ... N Polar magnet, 10S ... S pole magnet, 11 ... fixing means, 12a ... first group, 12b ... second group, 12c ... third group, 13 ... control section, 16 ... magnetic field lines, 17a ... first circle Ring magnet, 17b ... second ring magnet, 17c ... third ring magnet, 18a ... first set, 18b ... second set, 18c ... third set, 20 ... fixing device, 21 ... guide Element

Claims (6)

A metal plate fixing device used when forming a large number of through-holes in a metal plate to be processed,
A base on which the metal plate to be processed is placed; and a spacer made of a magnetic material disposed between the base and the metal plate to be processed.
The base is provided with a fixing means for fixing the workpiece metal plate to the base via the spacer by the magnetic force of an electromagnet,
The electromagnet includes a center side magnet disposed on the base corresponding to at least a center portion of the workpiece metal plate, and an outer magnet disposed outside the center side magnet,
The center-side magnet and the outer magnet are a single annular N-pole magnet or an annular S-pole magnet, and a plurality of arc-shaped N-pole magnets and arc-shaped S-pole magnets around the center of the base. Alternately and annularly arranged, or N pole magnets and S pole magnets arranged vertically and horizontally and alternately,
The electromagnet is energized to each of the center side magnet and the outer magnet, and when the work metal plate is fixed to the base, the center side magnet is energized to generate a magnetic force, A fixing device for a metal plate to be processed, wherein a controller for energizing an outer magnet to generate magnetic force is connected.   The guide member for positioning and fixing an outer peripheral portion of the metal plate to be processed when the metal plate to be processed is fixed to the base via the spacer by the fixing means. The fixing device of the metal plate to be processed according to 1.   The metal plate to be processed is a tube support plate having a large number of through-holes that are arranged inside a steam generator and into which a large number of heat transfer tubes are inserted. The fixing apparatus of the to-be-processed metal plate of description. A method for fixing a metal plate to be processed when forming a large number of through holes in the metal plate to be processed,
A base on which the metal plate to be processed is placed; and a spacer made of a magnetic material disposed between the base and the metal plate to be processed. A fixing means for fixing the workpiece metal plate to the base via the center magnet, the electromagnet being disposed on the base corresponding to at least a center portion of the workpiece metal plate, It possesses an outer magnet from said center-side magnets arranged outside, and the center-side magnet and the outer magnet, with a single annular N-pole magnet or toric S pole magnet, a plurality of arcuate Using a fixing device in which N-pole magnets and arc-shaped S-pole magnets are alternately and annularly arranged around the center of the base, or N-pole magnets and S-pole magnets are alternately arranged vertically and horizontally ,
Placing the metal plate to be processed on the base via the spacer;
A step of energizing the center side magnet of the electromagnet to generate a magnetic force, and fixing a center portion of the metal plate to be processed;
A step of energizing the outer magnet to generate a magnetic force while fixing the central portion of the metal plate to be processed, and fixing the outer portion from the central portion of the metal plate to be processed. Fixing method of work piece metal plate. After the step of fixing the outside of the center part of the workpiece metal plate
The method for fixing a metal plate to be processed according to claim 4, further comprising a step of positioning and fixing the outer peripheral portion of the metal plate to be processed on the spacer by a guide member.   The metal plate to be processed is a tube support plate having a large number of through-holes that are arranged inside a steam generator and into which a large number of heat transfer tubes are inserted. The fixing method of the to-be-processed metal plate of description.

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