JP2015031575A - Drain hole closing tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drain hole closing tool by means of which a drain hole can be properly closed even there is variation in inner diameter dimension of the drain hole.SOLUTION: The drain hole closing tool includes: a housing 101 which is formed into a cylindrical shape whose tip can be inserted into a drain hole 81; a rod 111 supported in the housing 101 in a movable state in an axial direction, and whose tip has a large diameter part 118 having diameter larger than inner diameter of the housing 101; an annular elastic seal member 121 which is provided between the tip of the housing 101 and the rear end of the large diameter part 118, and which is compressed resulting in outer diameter expansion, so that the annular elastic seal member 121 tightly contacts an inner wall surface of the drain hole 81; and a stopper 131 which is supported in the housing 101 movably in a direction crossing to the axial direction of the rod 111, and which blocks forward movement of the rod 111 to the housing 101, so that the tight contact state of the annular elastic seal member 121 with respect to the inner wall surface can be maintained.

Description

  The present invention relates to a drain hole closing tool used to close a drain hole provided in a lower part of a container or the like.

  A nuclear power plant is constituted by, for example, a nuclear reactor, a steam turbine, a generator, and the like. When a pressurized water reactor (PWR) is applied as a nuclear reactor, the pressurized water reactor uses light water as a reactor coolant and neutron moderator, and high-temperature high-pressure water that does not boil over the entire core. Generate. The steam generator exchanges heat between the high-temperature and high-pressure water (primary cooling water) and the secondary cooling water to generate steam. The steam turbine drives the turbine with the steam, and the generator generates power with the driving force.

  In this steam generator, a tube group outer cylinder is disposed at a predetermined distance from an inner wall surface in a hollow hermetically sealed body portion, and a plurality of inverted U-shaped heat transfer tubes are arranged in the tube group outer cylinder. An end portion of each heat transfer tube is supported by the tube plate, and an inlet side water chamber mirror and an outlet side water chamber mirror of the primary cooling water are formed at the lower end portion of the trunk portion. In addition, the body portion is located above the outer tube of the tube group and is provided with an inlet portion for secondary cooling water, and a steam / water separator and a moisture separator are arranged vertically, There is a steam outlet. Accordingly, when the primary cooling water is supplied to the plurality of heat transfer tubes, and the secondary cooling water is supplied into the body portion, heat exchange is performed between the primary cooling water (hot water) and the secondary cooling water (cold water). The secondary cooling water can absorb heat and generate water vapor.

  By the way, it is necessary for the steam generator to periodically inspect a plurality of heat transfer tubes in order to ensure sufficient safety and reliability. For example, when inspecting a heat transfer tube of a steam generator, the internal primary cooling water and secondary cooling water are discharged. The primary cooling water is discharged from an inlet nozzle, an outlet nozzle, and a manhole provided in the lower part, but the cooling water accumulated at the bottom is passed through a drain hole. After discharging the cooling water to the outside, the inlet nozzle and the outlet nozzle are fitted with a nozzle lid from the inside to prevent the cooling water from entering from the inlet nozzle and the outlet nozzle, and cooling from the inlet nozzle and the outlet nozzle. Prevents inspection tools, etc., from dropping into the water piping. Moreover, the drain hole prevents the intrusion of cooling water from the drain hole by mounting a closing tool from the inside.

  As a conventional drain hole closing tool, for example, it may be described in Patent Document 1 below. The drain hole closing tool described in Patent Document 1 is arranged in a rod pipe having a large-diameter portion at a distal end portion, a rubber ring is provided between the distal end of the pipe and the large-diameter portion, and the proximal end of the rod is provided. Constructed by providing an operation lever with an eccentric cam that is pivotally connected by a fixed pin, and the large diameter part compresses the rubber ring and expands its outer diameter by pivoting the operation lever. Is closed.

Japanese Patent Laid-Open No. 10-103609

  In the conventional drain hole closing tool described above, the outer peripheral surface of the rubber ring is made the inner peripheral surface of the drain hole by compressing the rubber ring in the axial direction and expanding the outer periphery in a drum drum shape. Seal closely. At this time, by inserting the fixing pin of the rod into the locking portion of the fixing slot, the operating lever is fixed at that position, and the sealed state of the drain hole is maintained.

  However, the drain hole may have variations in the inner diameter due to processing errors. For example, if the inner diameter of the drain hole is processed to be slightly larger than the specified value, after moving the large diameter portion with the operating lever and inflating the rubber ring, the fixing pin is inserted into the locking portion and the position of the operating lever When the is fixed, the rubber ring may not be sufficiently in close contact with the inner peripheral surface of the drain hole and the sealing performance may be deteriorated.

  The present invention solves the above-described problems, and an object of the present invention is to provide a drain hole closing tool capable of properly closing a drain hole even if the inner diameter dimension of the drain hole varies.

  In order to achieve the above object, a drain hole closing tool according to the present invention is a drain hole closing tool which is inserted into a drain hole and can be closed, and has a cylindrical shape whose tip can be inserted into the drain hole. A housing, a rod that is supported in the housing so as to be movable in an axial direction, and has a large-diameter portion having an outer diameter larger than the inner diameter of the housing at a distal end portion; a distal end of the housing and a rear portion of the large-diameter portion; An annular elastic seal member that is provided between the end and is compressed so that the outer diameter is enlarged and can be brought into close contact with the inner wall surface of the drain hole, and the housing moves in a direction intersecting the axial direction of the rod A stopper that is freely supported and that can keep the annular elastic seal member in close contact with the inner wall surface of the drain hole by preventing the rod from moving forward with respect to the housing by an inclined surface. And it is characterized in and.

  Accordingly, when the distal end portion of the closing tool is inserted into the drain hole and the rod is moved backward with respect to the housing by the moving device, the annular elastic seal member is compressed by the housing and the large diameter portion, so that the outer diameter is expanded and the drain is Close to the inner wall of the hole. Here, by moving the stopper and preventing the rod from moving forward with respect to the housing by the inclined surface, the close contact state of the annular elastic seal member to the inner wall surface of the drain hole is maintained. At this time, since the forward movement of the rod is prevented by the movement of the stopper, the annular elastic seal member can be properly brought into close contact with the inner wall surface of the drain hole even if the inner diameter dimension of the drain hole varies. It can be closed properly.

  In the drain hole closing tool of the present invention, the inclined surface is provided on the front surface side of the rod and is provided on the rear surface side of the stopper and the first inclined surface that is inclined with respect to the axial center direction of the rod. A second inclined surface inclined with respect to the axial direction of the rod, wherein the first inclined surface and the second inclined surface are set at the same angle.

  Therefore, when the stopper is moved, the first inclined surface of the rod and the second inclined surface of the stopper come into contact with each other, and the forward movement of the rod is prevented by the frictional resistance. The close contact state of the annular elastic seal member with the inner wall surface of the drain hole can be properly maintained.

  In the drain hole closing tool according to the present invention, the stopper has a cylindrical shape, is supported through the housing, and the rod is movably penetrated.

  Therefore, since the stopper has a cylindrical shape and the rod passes through the stopper, the stopper does not fall out of the housing, and loss of components at the work place can be prevented.

  In the drain hole closing tool according to the present invention, the rod has a first rod portion provided with the large-diameter portion at a distal end portion, and a second rod portion that can be engaged with the stopper, and the first rod The part is characterized in that the rear end part penetrates the second rod part and is supported by the fastening member to prevent the part from coming off.

  Therefore, by releasing the fastening member, the first rod portion can be separated from the second rod portion and removed from the housing, and the annular elastic seal member can be easily replaced.

  The drain hole closing tool according to the present invention is characterized in that a biasing member is provided for biasing the stopper toward the side of preventing the rod from moving forward relative to the housing.

  Therefore, the close contact state of the annular elastic seal member with respect to the inner wall surface of the drain hole can be properly maintained by biasing the stopper to the side that prevents the rod from moving forward by the biasing member.

  The drain hole closing tool of the present invention is characterized in that a moving device capable of retracting the rod with respect to the housing is provided.

  Therefore, the annular elastic seal member can be easily brought into close contact with the inner wall surface of the drain hole by retracting the rod with respect to the housing by the moving device.

  The drain hole closing tool according to the present invention is characterized in that a detection device for detecting a close force of the annular elastic seal member to the inner wall surface of the drain hole is provided.

  Therefore, when the close force of the annular elastic seal member to the inner wall surface of the drain hole is detected by the detection device, the rod can be retracted by an appropriate distance by the moving device, and the annular elastic seal member can be moved at an appropriate pressure. It can be brought into close contact with the inner wall surface of the drain hole.

  In the drain hole closing tool of the present invention, the detection device is urged in a direction in which the indicator approaches the housing with an indicator supported at the rear end of the housing so as to be movable in the axial direction. An urging spring; and a measuring unit that determines whether or not a close force of the annular elastic seal member to the inner wall surface of the drain hole is equal to or greater than a predetermined value by measuring a separation distance of the indicator with respect to the housing. It is characterized by having.

  Therefore, after the annular elastic seal member is brought into close contact with the inner wall surface of the drain hole, the indicator is separated from the housing against the urging force of the urging spring, and the distance of the indicator from the housing is measured by the measuring unit. Thus, it can be determined whether or not the close contact force of the annular elastic seal member to the inner wall surface of the drain hole is equal to or greater than a specified value, and workability can be improved.

  According to the drain hole closing tool of the present invention, since the stopper that is supported by the housing so as to be movable in the direction crossing the axial direction of the rod and prevents the rod from moving forward with respect to the housing is provided, the inner diameter of the drain hole varies. Even if there is, the annular elastic seal member can be properly brought into close contact with the inner wall surface of the drain hole, and the drain hole can be properly closed.

FIG. 1 is a partially cutaway side view showing a drain hole closing tool of the present embodiment. FIG. 2 is a partially cutaway plan view showing the drain hole closing tool of the present embodiment. 3 is a cross-sectional view taken along the line III-III in FIG. FIG. 4 is a front view showing a drain hole closing tool. FIG. 5 is a side view showing a closing operation by a drain hole closing tool. FIG. 6 is a side view showing the close contact force detection work by the drain hole closing tool. FIG. 7 is a schematic configuration diagram of a nuclear power plant. FIG. 8 is a schematic configuration diagram showing a steam generator. FIG. 9 is a cross-sectional view showing a water chamber mirror in the steam generator.

  Exemplary embodiments of a drain hole closing tool according to the present invention will be described below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this Example, Moreover, when there exists multiple Example, what comprises combining each Example is also included.

  FIG. 7 is a schematic configuration diagram of a nuclear power plant, FIG. 8 is a schematic configuration diagram illustrating a steam generator, and FIG. 9 is a cross-sectional view illustrating a water chamber mirror in the steam generator.

  The nuclear reactor of this embodiment uses light water as a reactor coolant and neutron moderator, and generates high-temperature and high-pressure water that does not boil over the entire core and sends this high-temperature and high-pressure water to a steam generator to generate steam by heat exchange. This is a pressurized water reactor (PWR) that generates electricity by sending this steam to a turbine generator.

  In the nuclear power plant having the pressurized water reactor of the present embodiment, as shown in FIG. 7, the reactor containment vessel 11 stores therein the pressurized water reactor 12 and the steam generator 13, and this pressurized water type The nuclear reactor 12 and the steam generator 13 are connected via a high temperature side supply pipe 14 and a low temperature side supply pipe 15, and a pressurizer 16 is provided in the high temperature side supply pipe 14, and the low temperature side supply pipe is provided. A primary cooling water pump 17 is provided at 15. In this case, light water is used as a moderator and primary cooling water (cooling material), and the primary cooling system maintains a high pressure state of about 150 to 160 atm by the pressurizer 16 in order to suppress boiling of the primary cooling water in the core. You are in control.

  Accordingly, in the pressurized water reactor 12, light water is heated as the primary cooling water by the low-enriched uranium or MOX as the fuel (nuclear fuel), and the high temperature primary cooling water is maintained at a predetermined high pressure by the pressurizer 16. , And is sent to the steam generator 13 through the high temperature side supply pipe 14. In the steam generator 13, heat exchange is performed between the high-temperature and high-pressure primary cooling water and the secondary cooling water, and the cooled primary cooling water is returned to the pressurized water reactor 12 through the low-temperature side supply pipe 15. .

  The steam generator 13 is connected to a steam turbine 32 via a pipe 31 for supplying heated secondary cooling water, that is, steam, and a main steam isolation valve 33 is provided in the pipe 31. The steam turbine 32 includes a high-pressure turbine 34 and a low-pressure turbine 35, and a generator (power generation device) 36 is connected to the steam turbine 32. Further, the high pressure turbine 34 and the low pressure turbine 35 are provided with a moisture separation heater 37 therebetween, and a cooling water branch pipe 38 branched from the pipe 31 is connected to the moisture separation heater 37, while the high pressure turbine 34 and the moisture separation heater 37 are connected by a low-temperature reheat pipe 39, and the moisture separation heater 37 and the low-pressure turbine 35 are connected by a high-temperature reheat pipe 40.

  Further, the low-pressure turbine 35 of the steam turbine 32 includes a condenser 41. The condenser 41 is connected to a turbine bypass pipe 43 having a bypass valve 42 from the pipe 31, and is also supplied with cooling water (for example, , Seawater) is connected to a water intake pipe 44 and a drain pipe 45. The intake pipe 44 has a circulating water pump 46, and the other end portion thereof is disposed in the sea together with the drain pipe 45.

  The condenser 41 is connected to a pipe 47, and is connected to a condensate pump 48, a ground condenser 49, a condensate demineralizer 50, a condensate booster pump 51, and a low-pressure feed water heater 52. The piping 47 is connected to a deaerator 53 and is provided with a main feed water pump 54, a high-pressure feed water heater 55, and a main feed water control valve 56.

  Therefore, the steam generated by exchanging heat with the high-temperature and high-pressure primary cooling water in the steam generator 13 is sent to the steam turbine 32 (from the high-pressure turbine 34 to the low-pressure turbine 35) through the pipe 31. The turbine 32 is driven to generate power by the generator 36. At this time, the steam from the steam generator 13 drives the high-pressure turbine 34, and then the moisture contained in the steam is removed and heated by the moisture separation heater 37, and then the low-pressure turbine 35 is driven. Then, the steam that has driven the steam turbine 32 is cooled using seawater in the condenser 41 to become condensed water, and the ground condenser 49, the condensate demineralizer 50, the low pressure feed water heater 52, the deaerator 53, the high pressure It returns to the steam generator 13 through the feed water heater 55 or the like.

  In the steam generator 13 of the nuclear power plant configured as described above, as shown in FIG. 8, the body portion 61 has a sealed hollow cylindrical shape, and the lower portion has a slightly smaller diameter with respect to the upper portion. The body 61 is provided with a tube group outer cylinder 62 having a cylindrical shape with a predetermined distance from the inner wall surface at the lower portion thereof. The tube group outer cylinder 62 has a plurality of tube support plates 63 disposed therein corresponding to a predetermined height position, and a tube plate 64 is fixed below the tube support plate 63. The tube support plate 63 is supported by a plurality of stay rods 65 extending upward from the tube plate 64. The tube group outer cylinder 62 is provided with a heat transfer tube group 67 including a plurality of heat transfer tubes 66 having an inverted U shape.

  In the heat transfer tube group 67, each heat transfer tube 66 has a U-bend portion 68 having an upper portion as a U-shaped portion and a lower end portion that is expanded and supported by the tube plate 64, and an intermediate portion (intermediate portion). Are supported by a plurality of tube support plates 63. In the U-bend portion 68, a plurality of heat transfer tubes 66 are disposed substantially in parallel with the inner and outer directions (vertical direction) of the tube group outer tube 62, and substantially parallel to the radial direction (horizontal direction) of the tube group outer tube 62. Are arranged. Further, the U-bend portion 68 is provided with a steady metal fitting 69 that suppresses vibration in the in-plane direction (left-right direction) of each heat transfer tube 66.

  The body portion 61 is formed with a water chamber mirror 61 a having a spherical lower portion, and an entrance chamber 71 and an exit chamber 72 are defined by a partition wall 70 provided below the tube plate 64 and an inlet nozzle 73. And one end of each heat transfer tube 66 communicates with the entrance chamber 71 and the other end communicates with the exit chamber 72.

  In addition, the body 61 has an air-water separator 75 that separates the feed water into steam and hot water above the heat transfer tube group 67, and removes the moisture of the separated steam so as to be in a state close to dry steam. A moisture separator 76 is provided. In addition, the body 61 is connected with a water supply pipe 77 for supplying secondary cooling water between the heat transfer tube group 67 and the steam separator 75, and a steam outlet 78 is formed in the ceiling. ing. That is, the secondary cooling water supplied to the inside from the water supply pipe 77 flows down between the tube group outer cylinders 62, circulates upward in the tube sheet 64, and rises in the heat transfer pipe group 67. Heat exchange with hot water (primary cooling water) flowing in the heat transfer tube 66 is performed.

  Therefore, as shown in FIGS. 7 and 8, the primary cooling water heated in the pressurized water reactor 12 is sent to the entrance 71 of the steam generator 13 through the high-temperature side feed pipe 14, and the inside of the large number of heat transfer tubes 66. It circulates through and reaches the exit chamber 72. On the other hand, the secondary cooling water cooled by the condenser 41 is sent to the water supply pipe 77 of the steam generator 13 through the pipe 47 and flows in the heat transfer pipe 66 through the trunk portion 61 (primary cooling water). And heat exchange. That is, in the body 61, heat is exchanged between the high-pressure and high-temperature primary cooling water and the secondary cooling water inside, and the cooled primary cooling water is supplied from the outlet chamber 72 through the low-temperature side feed pipe 15 into a pressurized water type. Returned to reactor 12. On the other hand, the secondary cooling water subjected to heat exchange with the high-pressure and high-temperature primary cooling water rises in the body 61 and is separated into steam and hot water by the steam-water separator 75, and this is separated by the moisture separator 76. The moisture of the steam is removed and sent from the steam outlet 78 to the steam turbine 32 through the pipe 31.

  By the way, it is necessary for the steam generator 13 to periodically inspect the heat transfer tubes 66 and the like, and in this case, the internal primary cooling water and the secondary cooling water are discharged to perform the work. That is, as shown in FIGS. 8 and 9, the steam generator 13 includes a water chamber mirror 61 a having a spherical shape formed in the lower portion of the body portion 61, an entrance chamber 71 and an exit chamber 72, and an inlet nozzle. 73 is connected to the high temperature side supply pipe 14, and the outlet nozzle 74 is connected to the low temperature side supply pipe 15. The water chamber mirror 61a is formed with two working manholes (not shown). Then, with the lid attached to the working manhole, the water chamber mirror 61a is filled with the primary cooling water, and when a part of the primary cooling water in the pressurized water reactor 12 is discharged, the steam generator located at a high position The primary cooling water in 13 is discharged.

  However, since the water chamber mirror 61a has a spherical shape and a little amount of primary cooling water accumulates at the bottom of the center, a drain hole 81 that connects the center bottom of the water chamber mirror 61a and the inlet nozzle 73 is formed. Has been. Therefore, the primary cooling water collected at the bottom of the water chamber mirror 61 a is discharged from the drain hole 81 through the inlet nozzle 73 to the high temperature side supply pipe 14. When all the primary cooling water in the water chamber mirror 61a is discharged, the lid of the work manhole is removed, and an operator wearing predetermined work clothes enters the water chamber mirror 61a. Wear. In this case, the inlet nozzle 73 has a hold-down ring 83 formed in advance on the inner side of the water chamber mirror 61a, and fixes the nozzle lid 82 by welding via the gasket 84. Further, the drain hole 81 is blocked by mounting the closing tool 100 from the inside.

  In addition, although the inlet nozzle 73 was demonstrated here, the nozzle nozzle is similarly attached to the outlet nozzle 74, and the drain hole currently formed is blocked | prevented with a closing tool.

  Thereafter, in the pressurized water reactor 12, primary cooling water is supplied to an upper cavity (not shown) in order to perform a fuel exchange operation. Here, the primary cooling water reaches the feed pipes 14 and 15 of the steam generator 13, but the nozzle lid 82 prevents the primary cooling water from entering the water chamber mirror 61a.

  Here, the closing tool 100 for closing the drain hole 81 described above will be described.

  FIG. 1 is a partially cutaway side view showing a drain hole closing tool of the present embodiment, FIG. 2 is a partially cutaway plan view showing a drain hole closing tool of the present embodiment, and FIG. -III sectional view, FIG. 4 is a front view showing a drain hole closing tool, FIG. 5 is a side view showing a closing operation with a drain hole closing tool, and FIG. 6 is a close force detection operation with a drain hole closing tool. It is a side view showing.

  In the closing tool 100, as shown in FIGS. 1 to 3, the housing 101 has a cylindrical shape, and the tip can be inserted into the drain hole 81. The housing 101 includes a first tube portion 102 on the front end side and a second tube portion 103 on the rear end side. The first cylinder portion 102 has an outer diameter smaller than the inner diameter of the drain hole 81, and the second cylinder portion 103 has an outer diameter larger than the inner diameter of the drain hole 81. The first cylindrical portion 102 and the second cylindrical portion 103 are integrally connected so as to be continuous at the stepped portion 104, and a ring-shaped flange portion 105 is formed at the rear end portion of the second cylindrical portion 103. . In this case, the housing 101 has an outer diameter and an inner diameter that the second cylinder portion 103 is larger than the first cylinder portion 102.

  The rod 111 is supported in the housing 101 so as to be movable along the axial direction. The rod 111 includes a first rod portion 112 on the front end side and a second rod portion 113 on the rear end side. The first rod part 112 has an outer diameter slightly smaller than the inner diameter of the first cylinder part 102, and the second rod part 113 has an outer diameter slightly smaller than the inner diameter of the second cylinder part 103. The first rod portion 112 has a small-diameter screw portion 114 formed at the rear end portion, while the second rod portion 113 has a through-hole 115 formed at the front end portion side and a small diameter at the rear end portion side. The through hole 115 and the screw hole 116 are formed to communicate with each other on the same axis. The first rod portion 112 has a rear end portion inserted through the through hole 115 of the second rod portion 113 and comes into contact with the step portion, and the screw portion 114 is screwed into the screw hole 116 and the end portion protrudes rearward. The nut (fastening member) 117 is fastened by screwing.

  Therefore, the rod 111 is configured by integrally connecting the first rod portion 112 and the second rod portion 113, the first rod portion 112 is supported movably in the first tube portion 102, and the second rod portion 113. Is movably supported in the second cylindrical portion 103.

  The rod 111 is provided with a large-diameter portion 118 having an outer diameter larger than the inner diameter of the housing 101 at the distal end portion of the first rod portion 112. The large-diameter portion 118 is set to have an outer diameter that is substantially the same as the outer diameter of the housing 101, and has a tapered tip and a hemispherical shape.

  The annular elastic seal member 121 is provided between the front end of the first cylindrical portion 102 in the housing 101 and the rear end of the large diameter portion 118 in the rod 111. The annular elastic seal member 121 has a cylindrical shape, the first mounting portion 122 on the front end side is fixed to the rear end of the large diameter portion 118, and the second mounting portion 123 on the rear end side is the front end of the first cylindrical portion 102. It is fixed to. The annular elastic seal member 121 is provided with an enlarged portion 124 between the mounting portions 122 and 123, and the rod 111 moves backward with respect to the housing 101, whereby the tip of the first tube portion 102 and the large diameter portion 118. Compressed by the rear end, the outer diameter is expanded and the inner wall surface of the drain hole 81 can be brought into close contact.

  The stopper 131 has a square cylindrical shape, and the plan view (FIG. 2) has a triangular shape. The stopper 131 is supported by the housing 101 so as to be movable in a direction intersecting (orthogonal) with the axial direction of the rod 111, and by preventing the rod 111 from moving forward with respect to the housing 101, the stopper 131 has an annular shape toward the inner wall surface of the drain hole 81. The close contact state of the elastic seal member 121 can be maintained.

  That is, the housing 101 has a through-hole 106 formed in the second cylindrical portion 103 along the horizontal direction. The through hole 106 includes a first through hole 107 formed on one side portion of the second cylindrical portion 103 and a second through hole 108 formed on the other side portion. The first through hole 107 and the second through hole 108 have a quadrangular shape through which the stopper 131 can be inserted and are set to have the same height, while the width of the first through hole 107 is larger than that of the second through hole 108. Is set. The first through hole 107 and the second through hole 108 are inclined surfaces 107a, 107b, 108a, 108b whose front and rear end surfaces in the axial direction correspond to the triangular shape of the stopper 131.

  On the other hand, since the stopper 131 has a triangular shape in plan view, the distal end portion 131b is thinner than the proximal end portion 131a, the front inclined surface 132 is formed on one side, and the rear inclined surface ( (Second inclined surface) 133 is formed. The stopper 131 penetrates the first through hole 107 and the second through hole 108 of the housing 101 and is movable in the horizontal direction. The stopper 131 has a front inclined surface 132 that can contact the inclined surfaces 107 a and 108 a of the through holes 107 and 108, and a rear inclined surface 133 that can contact the inclined surfaces 107 b and 108 b of the through holes 107 and 108. It has become. In this case, since the stopper 131 has a rectangular cylindrical shape, the inclined surfaces 132 and 133 have upper and lower inclined surfaces 132a, 132b, 133a, and 133b.

  Further, the stopper 131 has the first rod portion 112 of the rod 111 passing through the hollow portion. In addition, the rod 111 has an inclined surface (first inclined surface) 119 formed at the tip of the second rod portion 113. The stopper 131 has a rear inclined surface 133 that can contact the inclined surface 119 of the second rod portion 113. In this case, the front inclined surface 132 of the stopper 131 and the inclined surfaces 107a and 108a of the housing 101 are set at the same angle, the rear inclined surface 133 of the stopper 131, the inclined surfaces 107b and 108b of the housing 101, and the tip of the second rod portion 113. The inclined surface 119 is set at the same angle at the part.

  The stopper 131 is provided with a tension spring (biasing portion) 134 that biases the rod 111 toward the side that prevents the rod 111 from moving forward with respect to the housing 101. One end of the tension spring 134 is hooked to the mounting portion 109 of the housing 101, and the other end is locked to the mounting portion 135 of the stopper 131. Therefore, the stopper 131 is urged to the side where the tip 131b penetrates into the through hole 106.

  Therefore, inclined surfaces 133 and 119 that are inclined with respect to the axial direction of the rod 111 are provided between the stopper 131 and the second rod portion 113, the stopper 131 moves forward, and the rear inclined surface 133 is the second rod. By contacting the inclined surface 119 of the portion 113, the forward movement of the rod 111 with respect to the housing 101 is prevented by the frictional resistance between the inclined surfaces 133 and 119. The stopper 131 prevents the rod 111 from moving forward with respect to the housing 101 by the urging force of the tension spring 134 in addition to the frictional resistance of the inclined surfaces 133 and 119.

  In addition, the rod 111 has a first screw portion 141 formed at the rear portion of the second rod portion 113, and a nut 142 is screwed therein. The nut 142 abuts on the flange portion 105 of the housing 101, thereby preventing the rod 111 from moving forward with respect to the housing 101. That is, when the rear inclined surface 133 of the stopper 131 and the inclined surface 119 of the second rod portion 113 are in contact, the forward movement of the rod 111 is only blocked by the frictional resistance between the inclined surfaces 133 and 119 and the biasing force of the tension spring 134. Instead, the nut 142 is rotated and moved forward to come into contact with the flange portion 105 to completely prevent the rod 111 from moving forward.

  In the housing 101, a regulating member 143 is fixed to the upper part of the first cylindrical portion 102. When the leading end portion of the closing tool 100 is inserted into the drain hole 81, the restricting member 143 comes into contact with the periphery of the drain hole 81, that is, the bottom surface (the build-up weld portion) of the water chamber mirror 61a. This prevents insertion more than necessary and regulates the amount of insertion.

  The closing tool 100 is provided with a locking shaft 151 and an operation lever 161 (see FIG. 4) as a moving device that can retract the rod 111 with respect to the housing 101. The locking shaft 151 includes two shaft portions 152 and 153 that protrude left and right on the rear portion of the second rod portion 113 in the rod 111, that is, on the rear side of the first screw portion 141. As shown in FIG. 4, the operation lever 161 is configured by providing an operation portion 163 at the distal end portion of the bent lever portion 162. The operation portion 163 is formed with a locking notch 164 that can be locked to the locking shaft 151 and an eccentric cam 165 that engages with the flange portion 105. The eccentric cam 165 has an outer diameter that increases in the clockwise direction in FIG.

  Therefore, when the locking notch 164 of the operation lever 161 is locked to the locking shaft 151 and the lever 162 is rotated counterclockwise in FIG. 4, the eccentric cam 165 is engaged with the flange portion 105. As shown in FIG. 5, the rod 111 can be moved backward (moved rightward in FIG. 5) with respect to the housing 101.

  As shown in FIGS. 1 and 2, a detection device 171 for detecting the close force of the annular elastic seal member 121 to the inner wall surface of the drain hole 81 is provided. In this detection device 171, the rod 111 has a second screw part 172 having the same diameter as the first screw part 141 formed at the rear part of the second rod part 113, and a cylindrical support cylinder 173 is screwed. An indicator 174 is movably fitted to the rear portion of the support cylinder 173. The indicator 174 has a cylindrical shape and includes a fitting portion 175 that fits in the support cylinder 173 and a grip portion 176 that is integrally provided at the rear end portion of the fitting portion 175. A tension spring (biasing spring) 179 is adjusted between the fixing screw 177 of the support cylinder 173 and the fixing screw 178 of the indicator 174. The tension spring 179 biases the indicator 174 toward the housing 101.

  The indicator 174 is provided with a meter side portion 180 on the outer peripheral surface of the fitting portion 175. The measurement unit 180 is a display formed on the outer peripheral surface of the indicator 174, and is formed by painting a predetermined color on a ring-shaped notch. The annular elastic seal member 121 is compressed to increase the outer diameter, and is brought into close contact with the inner wall surface of the drain hole 81 with a predetermined pressure. The close contact force may be set to a predetermined value or more. It has been demanded. When the operator grips the grip 176 directly or with a tool (not shown) and moves the indicator 174 away from the support tube 173, the detection device 171 causes the urging force of the tension spring 179 to move the rod 111 backward. This acts as an operating force, that is, a force for peeling the annular elastic seal member 121 from the inner wall surface of the drain hole 81.

  In this case, when the indicator 174 is moved rearward with respect to the support cylinder 173 and the measurement unit 180 hidden behind the support cylinder 173 is exposed, the force for peeling the annular elastic seal member 121 from the inner wall surface of the drain hole 81 is the aforementioned. The urging force of the tension spring 179 is adjusted so that the specified value is obtained. That is, if the indicator 174 is moved rearward and the measuring unit 180 is exposed, the annular elastic seal member 121, that is, the rod 111 does not move, the close force of the annular elastic seal member 121 to the inner wall surface of the drain hole 81. If the rod 111 moves at this time, the close contact force of the annular elastic seal member 121 to the inner wall surface of the drain hole 81 becomes lower than the specified value. That is, by measuring the separation distance of the indicator 174 from the housing 101, it is possible to determine whether or not the close force of the annular elastic seal member 121 to the inner wall surface of the drain hole 81 is equal to or greater than a predetermined value.

  Here, the installation work of the closing tool 100 of the present embodiment will be described. First, as shown in FIG. 4, the tip of the closing tool 100 is inserted into the drain hole 81 by a predetermined length. At this time, in the housing 101, the insertion amount of the closing tool 100 is restricted by the restriction member 143 coming into contact with the bottom surface of the water chamber mirror 61a. Next, when the locking notch 164 of the operating lever 161 is locked to the locking shaft 151 and the operating lever 161 is rotated counterclockwise by a predetermined angle in FIG. 4, the eccentric cam 165 is brought into contact with the flange portion 105. By engaging, the rod 111 moves backward with respect to the housing 101 as shown in FIG. Then, the large-diameter portion 118 of the rod 111 moves backward to approach the tip of the first cylinder portion 102 and the annular elastic seal member 121 is compressed, whereby the outer diameter of the enlarged portion 124 is enlarged, and the drain hole 81 Close to the inner wall.

  At this time, the rear inclined surface 133 is brought into contact with the inclined surface 119 of the second rod portion 113 by moving the stopper 131 forward. Then, the forward movement of the rod 111 relative to the housing 101 is prevented by the frictional resistance between the inclined surfaces 133 and 119 and the biasing force of the tension spring 134. Then, the nut 142 is rotated and moved forward to come into contact with the flange portion 105 and completely prevent the rod 111 from moving forward.

  Thereafter, as shown in FIG. 6, when the indicator 174 is moved backward in the detection device 171 and the measuring unit 180 is exposed, the annular elastic seal member 121, that is, the rod 111 does not move, the annular elastic seal It is determined that the close force of the member 121 to the inner wall surface of the drain hole 81 is equal to or greater than a specified value.

  As described above, in the drain hole closing tool according to the present embodiment, the housing 101 having a cylindrical shape in which the tip portion can be inserted into the drain hole 81, and the housing 101 are supported so as to be movable in the axial direction. The outer diameter of the rod 111, which is provided between the front end of the housing 101 and the rear end of the large-diameter portion 118, is compressed by the rod 111 provided with a large-diameter portion 118 having an outer diameter larger than the inner diameter of the housing 101 at the distal end. An annular elastic seal member 121 that is enlarged and can be brought into close contact with the inner wall surface of the drain hole 81, and is supported by the housing 101 so as to be movable in a direction intersecting the axial direction of the rod 111 to prevent the rod 111 from moving forward relative to the housing 101. Thus, a stopper 131 capable of maintaining the close contact state of the annular elastic seal member 121 to the inner wall surface of the drain hole 81 is provided.

  Accordingly, when the distal end portion of the closing tool 100 is inserted into the drain hole 81 and the rod 111 is moved backward with respect to the housing 101 by the operation lever 161, the annular elastic seal member 121 is compressed by the housing 101 and the large diameter portion 118. As a result, the outer diameter expands and comes into close contact with the inner wall surface of the drain hole 81. Here, by moving the stopper 131 to prevent the rod 111 from moving forward relative to the housing 101, the close contact state of the annular elastic seal member 121 to the inner wall surface of the drain hole 81 is maintained. At this time, since the rod 111 is prevented from moving forward by the movement of the stopper 131, the annular elastic seal member 121 can be properly brought into close contact with the inner wall surface of the drain hole 81 even if the inner diameter of the drain hole 81 varies. The drain hole 81 can be properly closed.

  That is, when the rod 111 is retracted by the operation lever 161, the annular elastic seal member 121 is compressed and the outer diameter is enlarged and comes into close contact with the inner wall surface of the drain hole 81. Determined by. The amount of movement of the rod 111 varies depending on the inner diameter of the drain hole 81. For this reason, the close contact force to the drain hole 81 by the annular elastic seal member 121 is determined to be equal to or greater than a specified value. However, the movement amount of the rod 111 may be different for each drain hole 81, It is necessary to prevent the rod 111 from moving forward while the elastic seal member 121 is in close contact with the drain hole 81. Therefore, in this embodiment, the rod 131 is prevented from moving forward with respect to the housing 101 by moving the stopper 131.

  Specifically, the inclined surface 119 is provided on the front surface side of the rod 111, while the rear inclined surface 133 is provided on the rear surface side of the stopper 131, and the inclined surfaces 119 and 133 are set at the same angle. Therefore, when the stopper 131 is moved, the inclined surface 119 of the rod 111 and the rear inclined surface 133 of the stopper 131 come into contact with each other, and the forward movement of the rod 111 is prevented by the frictional resistance. Even if it exists, the close_contact | adherence state of the cyclic | annular elastic seal member 121 with respect to the inner wall face of the drain hole 81 can be maintained appropriately. That is, regardless of the position of the rod 111, the forward movement of the rod 111 can be easily prevented only by changing the movement amount of the stopper 131.

  In the drain hole closing tool of this embodiment, the stopper 131 has a cylindrical shape, penetrates and supports the housing 101, and the rod 111 penetrates movably. Accordingly, since the stopper 131 has a cylindrical shape and the rod 111 penetrates inside, the stopper 131 does not fall off from the housing 101 regardless of the position of the stopper 131, and the loss of components at the work place is prevented. be able to.

  In the drain hole closing tool of this embodiment, a first rod portion 112 having a large-diameter portion 118 provided at the tip portion and a second rod portion 113 that can be locked with a stopper 131 are provided, and the rear end of the first rod portion 112 is provided. The end portion passes through the second rod portion 113 and is supported by the nut 117 to prevent it from coming off. Therefore, by releasing the nut 117, the first rod portion 112 can be separated from the second rod portion 113 and removed from the housing 101, and the annular elastic seal member 121 can be easily replaced.

  In the drain hole closing tool of the present embodiment, a tension spring 134 is provided to urge the stopper 131 to the side that prevents the rod 111 from moving forward with respect to the housing 101. Therefore, when the stopper 131 is urged by the tension spring 134 to the side that prevents the rod 111 from moving forward, the close contact state of the annular elastic seal member 121 with respect to the inner wall surface of the drain hole 81 can be properly maintained.

  In the drain hole closing tool of this embodiment, a detection device 171 for detecting the close force of the annular elastic seal member 121 to the inner wall surface of the drain hole 81 is provided. Therefore, the detecting device 171 detects the close force of the annular elastic seal member 121 to the inner wall surface of the drain hole 81, so that the rod 111 can be retracted by an appropriate distance, and the annular elastic seal member 121 is The pressure can be brought into close contact with the inner wall surface of the drain hole 81.

  In the drain hole closing tool of this embodiment, as the detection device 171, an indicator 174 that is supported on the rear end of the housing 101 so as to be movable in the axial direction, and a direction in which the indicator 174 approaches the housing 101 are attached. Measurement to determine whether or not the close contact force of the annular elastic seal member 121 to the inner wall surface of the drain hole 81 is equal to or greater than a predetermined value by measuring the distance between the tension spring 179 and the indicator 174 with respect to the housing 101. Part 180. Therefore, after the annular elastic seal member 121 is brought into close contact with the inner wall surface of the drain hole 81, the indicator 174 is separated from the housing 101 against the urging force of the tension spring 179, and the indicator 174 with respect to the housing 101 is measured by the measuring unit 180. By measuring the separation distance, it is possible to determine whether or not the close force of the annular elastic seal member 121 to the inner wall surface of the drain hole 81 is equal to or greater than a specified value, and workability can be improved.

  In the above-described embodiment, the inclined surface 119 is provided on the front surface side of the rod 111, the rear inclined surface 133 is provided on the rear surface side of the stopper 131, and the inclined surfaces 119 and 133 are set at the same angle so that they can be contacted. However, the present invention is not limited to this configuration. For example, the inclined surface 119 may be provided only on the front surface side of the rod 111, or the rear inclined surface 133 may be provided only on the rear surface side of the stopper 131, and the inclined surfaces 119 and 133 may be set at different angles. Also good.

  In the above-described embodiment, the locking shaft 151 and the operation lever 161 are provided as a moving device capable of retracting the rod 111 with respect to the housing 101. However, the present invention is not limited to this configuration. As long as the rod 111 can be retracted, an electric power tool or the like may be used.

13 Steam Generator 61 Body 61a Water Chamber Mirror 66 Heat Transfer Tube 73 Inlet Nozzle 74 Outlet Nozzle 81 Drain Hole 82 Nozzle Cover 100 Closing Tool 101 Housing 102 First Tube Part 103 Second Tube Part 105 Flange Part 106 Through Hole 111 Rod 112 1st rod part 113 2nd rod part 117 Nut (fastening member)
118 large diameter portion 119 inclined surface (first inclined surface)
121 Annular elastic seal member 124 Enlarged portion 131 Stopper 133 Rear inclined surface (second inclined surface)
134 Tension spring (biasing member)
142 Nut 143 Restriction member 151 Locking shaft 161 Operation lever 171 Detection device 174 Indicator 180 Measurement unit

Claims (8)

A drain hole closing tool that is inserted into the drain hole and can be closed,
A housing having a cylindrical shape in which a distal end portion can be inserted into the drain hole;
A rod which is supported in the housing so as to be movable in the axial direction and has a large-diameter portion having an outer diameter larger than the inner diameter of the housing at the tip portion;
An annular elastic seal member that is provided between the front end of the housing and the rear end of the large-diameter portion and is compressed so that the outer diameter is enlarged and can be in close contact with the inner wall surface of the drain hole;
The annular elastic seal member is in close contact with the inner wall surface of the drain hole by being supported by the housing so as to be movable in a direction crossing the axial direction of the rod and preventing the rod from moving forward with respect to the housing by an inclined surface. A stopper capable of maintaining the state,
A drain hole closing tool characterized by comprising:   The inclined surface is provided on the front surface side of the rod and is inclined with respect to the axial direction of the rod, and the inclined surface is provided on the rear surface side of the stopper and is inclined with respect to the axial direction of the rod. 2. The drain hole closing tool according to claim 1, wherein the first inclined surface and the second inclined surface are set at the same angle.   3. The drain hole closing tool according to claim 1, wherein the stopper has a cylindrical shape, is supported through the housing, and allows the rod to pass through freely. 4.   The rod has a first rod portion provided with the large-diameter portion at a tip portion and a second rod portion that can be locked by the stopper, and the rear end portion of the first rod portion is the second rod portion. The drain hole closing tool according to any one of claims 1 to 3, wherein the drain hole is supported by a fastening member through the rod portion.   The drain hole closing tool according to any one of claims 1 to 4, further comprising a biasing member that biases the stopper toward a side that prevents the rod from moving forward with respect to the housing.   The drain hole closing tool according to any one of claims 1 to 5, wherein a moving device capable of retracting the rod with respect to the housing is provided.   The drain hole closing tool according to any one of claims 1 to 6, further comprising a detection device that detects a close force of the annular elastic seal member to an inner wall surface of the drain hole.   The detection device includes an indicator supported at a rear end portion of the housing so as to be movable in an axial direction, a biasing spring that biases the indicator toward the housing, and the indicator relative to the housing. And a measuring unit that determines whether or not the close contact force of the annular elastic seal member to the inner wall surface of the drain hole is equal to or greater than a predetermined value by measuring a separation distance of the drain hole. Drain hole closing tool described in 1.

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