CA1223983A - Machines for dismantling decommissioned nuclear reactors - Google Patents
Machines for dismantling decommissioned nuclear reactorsInfo
- Publication number
- CA1223983A CA1223983A CA000478533A CA478533A CA1223983A CA 1223983 A CA1223983 A CA 1223983A CA 000478533 A CA000478533 A CA 000478533A CA 478533 A CA478533 A CA 478533A CA 1223983 A CA1223983 A CA 1223983A
- Authority
- CA
- Canada
- Prior art keywords
- mast
- pressure vessel
- reactor
- machine
- dismantling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Abstract
Abstract Title: Machines for dismantling decommissioned nuclear reactors A machine for dismantling, unloading and transferring to a disposal facility, nuclear reactor structure and/or components, which have been irradiated during operation of the reactor. The machine includes in one example a gantry (12) mounted on a rigid, undismantled part of the reactor such as rails (10) on the refuelling level (9) of the reactor, a carriage (14) angularly movable on the gantry, a platform (141) movable linearly on the carriage, a mast (16) on and axially movable relative to the platform, a manipulator (17) mounted on the mast for angular and linear movement relative thereto, a variety of tools (18) selectively mountable on the manipulator for effecting dismantling of reactor structure and/or components, and hoist means (26) movable along a beam (21) rotable about the reactor centre line and alignable with other beams (23, 24) to allow transfer of the hoist means from one beam to another. Alternative arrangements for varying the elevation of the mast are also disclosed.
Description
~239~3 Machines for dismantling decommissioned nuclear reactors.
This invention relates to the decommissioning of nuclear reactors which are considered to have completed her operational life, and in particular, to machines for effecting dismantling of the reactor structure in a controlled and safe manner.
hen a nuclear reactor has reached the end of its planned operational fife, the alternatives, after removal of the nuclear fuel and reactor coolant, are to cover the whole structure with adequate shielding, such as a mound of soil 9 and take precautions for the covered reactor to be preserved BY shielded for all time as a permanent 'memorial', or to dismantle the structure of the reactor and dispose of the dismantled material in small amounts in conventional safe storage facilities, and as a result, restore the reactor site to its rebuilding state. The latter course is Jo be preferred, especially in view of doubts concerning the practicability of preserving the shielding integrity of the whole reactor structure over the period of thousands of years necessary before biologically unsafe amounts of radioactivity will have decayed away.
To put the present invention into context, consider a conventional gss-cooled, graphite moderated, nuclear reactor which has within a pressure vessel a core I including the moderator and the fuel elements, the ' latter being capable of being charged and discharged by a ~3~i~3 ruffling machine, and surrounding the core, heat exchangers which remove heat from coolant heated by circulation through the core and employ the removed heat to generate electricity for example employing steam and turbine. When such a reactor has completed its operational lifetime, let it be assumed that a decision has been reached to dismantle the reactor and restore the site. After normal discharge of the fuel elements and blow-down of the coolant gas it is considered acceptable from a safety point of view to employ conventional dismantling techniques for removal of the turbines, heat exchangers, refueling machine and, with adequate temporary shielding, the top dome of the pressure vessel 80 as to expose the core. In order to dismantle and remove the pressure vessel and to unload and transfer to a disposal facility the graphite moderator (which it in discrete block form) and other vessel internal, a machine is required which will perform these operation safely and expeditiously, and it it an object of the present invention to provide such a machine.
According to the invention, a machine for dismantling, unloading and transferring to a disposal facility, nuclear reactor structure including components which have been irradiated during operation of the reactor, comprises a vertically extending mast of adjustable longitudinal extent, means supporting the mast from a rigid undismantled part of the reactor whereby I, ;!.~
3~3 the mast extends into a pressure vessel of the reactor located beneath the supporting means, means for moving the mast transversely of its longitudinal axis whereby the mast can be moved into different positions within the interior of the pressure vessel, a manipulator mounted on the mast for movement relative thereto and for supporting and operating a variety of tool for effecting dismantling of the structure, a movable beam mounted beneath the supporting mean and above the pressure vessel, the beam extending transversely of the mast and being movable angularly in a horizontal plane over an area encompassing the range of the transverse movement of the mast, hoist means mounted for traverse along the beam and extendible into the pressure vessel for lifting parts of the pressure vessel after such parts have been prepared for disentailing by the tool-supporting manipulator, and at least one fixed beam mounted in the same horizontal plane as the movable beam for registration with the movable beam when the latter is in a predetermined angular orientation, the fixed beam when a registered forming a continuation of the movable beam whereby the hoist can be transferred from the movable beam onto the fixed beam and traversed to an unloading station. Preferably, all the features of the machine are controllable remotely. The movable beam may be mounted on & ring girder secured to the reactor structure to enable the movable beam to be rotated about the center ire of the pressure vessel. The movable beam may be ~2~3~3 mounted on the mast The supporting means may include structure rotatable about a vertical axis whereby the mast can be moved along an arc-shaped path within the pressure vessel. The machine may include a radiation S shield mounted for rotation above the movable beam, the radiation shield including an eccentrically-disposed entry opening through which the mast and the tool-carrying manipulator pass when the mast is extended into the pressure vessel, the mast being retractable in its entirety through the opening together with the manipulator, and the radiation shield including a removable section for insertion into the entry opening when the mast is 80 retracted. The mast may comprise an assembly of sections arranged so that sections can be added to and removed from the assembly to extend and retract the mast respectively. The mast may be of telescopic construction.
Also in accordance with the invention, a machine for dismantling, unloading and transferring to a disposal facility, nuclear reactor structure, including components which have been irradiated during operation of the reactor comprises a gantry, means mounting the gantry on a rigid, undismantled part of the reactor, a carriage mounted on the gantry for rotation about a vertical axis, a platform mounted on the carriage for movement diametrally thereof, a vertically extending mast of adjustable longitudinal extent supported by the platform whereby the mast extends into a pressure vessel aye of the reactor located beneath the gantry, the gantry, carriage and platform serving to move the mast transversely of its longitudinal axis whereby the mast can be moved into different positions within the interior of the pressure vessel, a manipulator mounted on the mast for movement relative thereto and for supporting and operating a variety of tools for effecting dismantling of the structure, a radiation shield mounted for rotation beneath the carriage and platform, the shield including an eccentrically disposed entry opening through which the mast passes when extended into the pressure vessel, the mast being retractable in its entirety through the opening together with the manipulator, and the shield including a removable closure section for insertion into the opening when the mast is a retracted, a movable beam mounted beneath the radiation shield and above the pressure vessel, the beam extending transversely of the mast and being movable angularly in a horizontal plane over an area encompassing the range of the transverse movement of the mast, hoist means mounted for traverse along the beam and extendible into the pressure vesflel for lifting parts of the pressure vessel after such part have been prepared for dismantling by said tool-supporting manipulator, and at least one fixed beam mounted in the same horizontal plane as the movable beam for registration with the movable beam when the latter it in a predetermined angular orientation, the fixed beam Lyle when 80 registered forming a continuation of the movable beam whereby the hoist can be transferred from the movable beam onto the fixed beam and traversed to an unloading station Constructional examples of machine according to the invention will now be described with reference to the accompanying diagrammatic drawings, wherein:-Figure 1 is a side view in section and Figure 2 a plan view of a nuclear reactor which it 0 it intended to dismantle with the aid of one of the machines shown in Figures 3 lo Figure 3 is a side view, Figure a plan view and Figure 5 a perspective view of one construction of -machine in operative position, Figure 6 is a side view, Figure 7 a plan view and Figure 8 a perspective view of another construction of machine in operative positlon9 I Figure 9 1B a side view and Figure 10 a plan view of a modification.
like reference numerals in the drawings illustrate like parts.
Referring firstly to Figures 1 and I these Figures show in diagrammatic form the gas-cooled, graphite moderated, nucleate reactor known as the Wind scale Advanced Gas-Cooled Reactor (WAR), which has now I,,, completed it useful life and it to be dismantled. The reactor core (not shown), which includes the graphite moderator and fuel element channels, and other internals such as core support (not shown), hot box 1 and refueling standplpe~ 2, are contained in a pressure vessel 3, the upper dome and the upper parts of the atandpipes 2 of which are shown removed. The volume which the upper dome occupied 18 intended to be employed for a dismantling, unloading and transferring machine, lo arch as one of those subsequently described heroin and referred to hereinafter inclusively a a 'handling motion The reactor also ha four heat exchanger housings 4, from which the heat exchangers have been dismantled and removed by conventional means with shielding precautions, since the radioactivity level of these structures is such as to permit such operations.
One of the buildings 4 (when emptied) it employed as a temporary repository 5 for dismantled material, in which sorting and designation for packaging in a communicating building 6 18 carried out, small sloe material which can be disposed of in bulk being dropped into a waste container 7 beneath the temporary repository I The outer containment of the reactor is retained end helps to retain integrity during dismantling and related operations. The packaging building 6 is outside the containment a and communicates via an air lock (not shown).
~23~3 The ruffling floor level it designated 9 in Figure 1, and it provided with rails 10 for the reactor refueling machine (already removed to run on.
Figures 3-5 show the reactor with a handling machine 11 in poaltlon. The machine 11 consists of a gantry 12 with wheel 13 funning on the acid rails 10, and a carriage I able to move angularly relative to the gantry 12 on a rail 15 on the gantry 12 (see particular Figures 4 and 5). The carriage 14 carries on a platform 14' movable linearly on the carriage 14 a mast 16 able to be extended and made shorter relative to the carriage 14 in a direction parallel to the axis of the reactor pressure vessel 3. There is a manipulator 17 mounted on the lower end of the mast 16 and movable in an angular and linear manner relative thereto, the manipulator 17 being capable of carrying cutting and the like tools 18 by mean of which the pressure vessel 3 and vessel internals may be dismantled prior to transfer for packaging. The mast 16 can be extended or made shorter by adding or taking away separate auctions provided with appropriate secure fastening expedients (not shown) of conventional kind.
A ring girder 19 carried by the reactor concrete structure 20 provides a track for a slew beam 21 to be rotated about the vessel center line and in one angular po~ltlon to be aligned and reglatered with fixed beams 22, 23. The beam 22 is an intermediate between the beam 21 and another slew beam 24 rotatable about the center by ~L~Z3~33 fine of that heat exchanger housing 4 which is used as the temporary repository 5. The beam 23 it a fixed beam extending into another heat exchanger housing 4, designated 25 and employed as a maintenance cell. There are for example two hoists 26, 27 movable along the beams 21, 22, 23, 24, the hoist 26 operating normally over the vessel 3 and movable into the cell 25, and the hoist 21 being normally situated over the repository 5 and on the clew beam 24 but being movable from the beam lo 24 to the beam 21 via the beam 22 and vice versa for transfer of material between the area of vessel 3 and the repository 5. There it soother fixed beam 28 with which beam 24 can be aligned and registered and which extends between repository 5 and another of the empty heat exchanger housings 4, this being designated 29 and employed for temporary waste storage. The hoist 27 can be made to travel from beam 24 to beam 28 and vice versa.
There 18 remotely controlled mechanism provided (not shown) for controlling and rotating the beams 21, I and for moving and operating the hoists 26, 27.
It 18 envisaged that the manipulator 17 and tools 18 are to be employed to cut the material of the pressure vessel into manageably-sized pieces, and that the hoist 26 with the aid of conventional gripping or possibly magnetic ].iftlng means on the end of the hoist cable (none shown), be used to transfer the pieces when cut to the repository 5 and thence to the packaging building 6 I' ~Z3~3 or to the temporary storage area 29. Furthermore, the hoist 26 would be used to pick up and transfer dismantled moderator blocks piecemeal to 5, 6 or 29.
In order to permit short-term access to the gantry S 12, carriage 14 and the upper area occupied by these components, and to obviate undue exposure of the component to radiation from vessel 3 and the vessel internals, rotatable shielding 30 with an eccentrically deposed removable shield circle 31 is provided to span the ring girder 20 (see Figures 3 and 4), the mast 16 being extendible, and the hoist 26 being operable, through the hole provided in the shielding 30 suitably rotated, when the circle 31 it removed. Figure 5 shows the mast 16 in its extended position with the manipulator 17 and tool I in position for attacking the material of vessel 3, whereas Figure 3 shows the mast 16, manipulator 17 and tool 18 in retracted position.
In an alternstlve construction, illustrated in Figures 6, 7 and 8, the handling machine if' has a 20 gantry 12 similar to the gantry 12 of the Figures 3-5 construction, with wheels 13 able to run on the existing falls 10 on the reactor charge face 9. A carriage 32 is mounted on the gantry 12 for cross-tra~el thereon.
mat 16 similar to the mat 16 of the Figures 3-5 construction is mounted on the carriage 32 and carries, a in the Figure 3-5 construction, a manipulator 17 capable of holding a tool 18.
AYE
isle The main difference from the Figures 3-S
construction 18 that there 18 a beam 33 radially mounted on a collar 34 rotatable on the mast 16. The beam 33 can be rotated by remote control of the collar 34 and can be made to align and register with an intermediate beam 22 or with a fixed beam 23, as was the beam 21 in the Figures 3-5 construction, except that, in this cave, alternative but not simultaneous registration 19 only possible. There is a slew beam 24 and fixed beam 28 as in the Figures 3-5 construction, and a hoist 27 operates between vessel 3 space and repository 5 or storage I
hoist 26 operates on beam 33 and can move on to beam 23 to operate in maintenance cell 25 or on to beam 24 via beam 22 to operate in cell 5. As in the Figures 3-5 construction, the mast 16 can be extended and shortened by adding or subtracting section.
The construction shown in Figures 9 and 10 provides a handling machine 11' which combines the slew beam 21 construction shown in Figures 3-5 with the gantry 12 and cross-travel carriage 32 of the Figures 6-8 construction, but is varied by having a telescopic mast 35 mounted on a platform 36 on the carriage 32 and having equipment, diagrammatically indicated as a windlass 37 and cable 38, for controlling the telescoping and untelescoping of the sections 39 of the mast 35.
In a modification, not illustrated, the slew beam 21 of the Figures 3-5 construction can, instead of being , I
~3~lS3 mounted on the separate ring girder 20 on the reactor building, be suspended rigidly from the rotatable carriage 14 of that construction, and be rotatable by virtue of the controlled rotation of that carriage 14 on the gantry 12, the beam corresponding to slew beam 21 thereby having its loading transferred to the falls 10 via the wheels 13 of gantry 12.
In another modification, not illustrated, the mast may be a rigid structure, and the elevation of the manipulator and tooting mounted thereon can be varied by providing means, operable remotely, for raising and towering the carriage relative to the gantry, whose elevation 18 fixed by being mounted on the said rails.
If desired, the manipulator may be mounted on an elevatable platform.
It will be appreciated that suitable biological shielding may be installed as and where necessary. For example, as floor mounted retractable shielding, and on the gantry itself, and for a maintenance cell beneath the gantry.
13~47
This invention relates to the decommissioning of nuclear reactors which are considered to have completed her operational life, and in particular, to machines for effecting dismantling of the reactor structure in a controlled and safe manner.
hen a nuclear reactor has reached the end of its planned operational fife, the alternatives, after removal of the nuclear fuel and reactor coolant, are to cover the whole structure with adequate shielding, such as a mound of soil 9 and take precautions for the covered reactor to be preserved BY shielded for all time as a permanent 'memorial', or to dismantle the structure of the reactor and dispose of the dismantled material in small amounts in conventional safe storage facilities, and as a result, restore the reactor site to its rebuilding state. The latter course is Jo be preferred, especially in view of doubts concerning the practicability of preserving the shielding integrity of the whole reactor structure over the period of thousands of years necessary before biologically unsafe amounts of radioactivity will have decayed away.
To put the present invention into context, consider a conventional gss-cooled, graphite moderated, nuclear reactor which has within a pressure vessel a core I including the moderator and the fuel elements, the ' latter being capable of being charged and discharged by a ~3~i~3 ruffling machine, and surrounding the core, heat exchangers which remove heat from coolant heated by circulation through the core and employ the removed heat to generate electricity for example employing steam and turbine. When such a reactor has completed its operational lifetime, let it be assumed that a decision has been reached to dismantle the reactor and restore the site. After normal discharge of the fuel elements and blow-down of the coolant gas it is considered acceptable from a safety point of view to employ conventional dismantling techniques for removal of the turbines, heat exchangers, refueling machine and, with adequate temporary shielding, the top dome of the pressure vessel 80 as to expose the core. In order to dismantle and remove the pressure vessel and to unload and transfer to a disposal facility the graphite moderator (which it in discrete block form) and other vessel internal, a machine is required which will perform these operation safely and expeditiously, and it it an object of the present invention to provide such a machine.
According to the invention, a machine for dismantling, unloading and transferring to a disposal facility, nuclear reactor structure including components which have been irradiated during operation of the reactor, comprises a vertically extending mast of adjustable longitudinal extent, means supporting the mast from a rigid undismantled part of the reactor whereby I, ;!.~
3~3 the mast extends into a pressure vessel of the reactor located beneath the supporting means, means for moving the mast transversely of its longitudinal axis whereby the mast can be moved into different positions within the interior of the pressure vessel, a manipulator mounted on the mast for movement relative thereto and for supporting and operating a variety of tool for effecting dismantling of the structure, a movable beam mounted beneath the supporting mean and above the pressure vessel, the beam extending transversely of the mast and being movable angularly in a horizontal plane over an area encompassing the range of the transverse movement of the mast, hoist means mounted for traverse along the beam and extendible into the pressure vessel for lifting parts of the pressure vessel after such parts have been prepared for disentailing by the tool-supporting manipulator, and at least one fixed beam mounted in the same horizontal plane as the movable beam for registration with the movable beam when the latter is in a predetermined angular orientation, the fixed beam when a registered forming a continuation of the movable beam whereby the hoist can be transferred from the movable beam onto the fixed beam and traversed to an unloading station. Preferably, all the features of the machine are controllable remotely. The movable beam may be mounted on & ring girder secured to the reactor structure to enable the movable beam to be rotated about the center ire of the pressure vessel. The movable beam may be ~2~3~3 mounted on the mast The supporting means may include structure rotatable about a vertical axis whereby the mast can be moved along an arc-shaped path within the pressure vessel. The machine may include a radiation S shield mounted for rotation above the movable beam, the radiation shield including an eccentrically-disposed entry opening through which the mast and the tool-carrying manipulator pass when the mast is extended into the pressure vessel, the mast being retractable in its entirety through the opening together with the manipulator, and the radiation shield including a removable section for insertion into the entry opening when the mast is 80 retracted. The mast may comprise an assembly of sections arranged so that sections can be added to and removed from the assembly to extend and retract the mast respectively. The mast may be of telescopic construction.
Also in accordance with the invention, a machine for dismantling, unloading and transferring to a disposal facility, nuclear reactor structure, including components which have been irradiated during operation of the reactor comprises a gantry, means mounting the gantry on a rigid, undismantled part of the reactor, a carriage mounted on the gantry for rotation about a vertical axis, a platform mounted on the carriage for movement diametrally thereof, a vertically extending mast of adjustable longitudinal extent supported by the platform whereby the mast extends into a pressure vessel aye of the reactor located beneath the gantry, the gantry, carriage and platform serving to move the mast transversely of its longitudinal axis whereby the mast can be moved into different positions within the interior of the pressure vessel, a manipulator mounted on the mast for movement relative thereto and for supporting and operating a variety of tools for effecting dismantling of the structure, a radiation shield mounted for rotation beneath the carriage and platform, the shield including an eccentrically disposed entry opening through which the mast passes when extended into the pressure vessel, the mast being retractable in its entirety through the opening together with the manipulator, and the shield including a removable closure section for insertion into the opening when the mast is a retracted, a movable beam mounted beneath the radiation shield and above the pressure vessel, the beam extending transversely of the mast and being movable angularly in a horizontal plane over an area encompassing the range of the transverse movement of the mast, hoist means mounted for traverse along the beam and extendible into the pressure vesflel for lifting parts of the pressure vessel after such part have been prepared for dismantling by said tool-supporting manipulator, and at least one fixed beam mounted in the same horizontal plane as the movable beam for registration with the movable beam when the latter it in a predetermined angular orientation, the fixed beam Lyle when 80 registered forming a continuation of the movable beam whereby the hoist can be transferred from the movable beam onto the fixed beam and traversed to an unloading station Constructional examples of machine according to the invention will now be described with reference to the accompanying diagrammatic drawings, wherein:-Figure 1 is a side view in section and Figure 2 a plan view of a nuclear reactor which it 0 it intended to dismantle with the aid of one of the machines shown in Figures 3 lo Figure 3 is a side view, Figure a plan view and Figure 5 a perspective view of one construction of -machine in operative position, Figure 6 is a side view, Figure 7 a plan view and Figure 8 a perspective view of another construction of machine in operative positlon9 I Figure 9 1B a side view and Figure 10 a plan view of a modification.
like reference numerals in the drawings illustrate like parts.
Referring firstly to Figures 1 and I these Figures show in diagrammatic form the gas-cooled, graphite moderated, nucleate reactor known as the Wind scale Advanced Gas-Cooled Reactor (WAR), which has now I,,, completed it useful life and it to be dismantled. The reactor core (not shown), which includes the graphite moderator and fuel element channels, and other internals such as core support (not shown), hot box 1 and refueling standplpe~ 2, are contained in a pressure vessel 3, the upper dome and the upper parts of the atandpipes 2 of which are shown removed. The volume which the upper dome occupied 18 intended to be employed for a dismantling, unloading and transferring machine, lo arch as one of those subsequently described heroin and referred to hereinafter inclusively a a 'handling motion The reactor also ha four heat exchanger housings 4, from which the heat exchangers have been dismantled and removed by conventional means with shielding precautions, since the radioactivity level of these structures is such as to permit such operations.
One of the buildings 4 (when emptied) it employed as a temporary repository 5 for dismantled material, in which sorting and designation for packaging in a communicating building 6 18 carried out, small sloe material which can be disposed of in bulk being dropped into a waste container 7 beneath the temporary repository I The outer containment of the reactor is retained end helps to retain integrity during dismantling and related operations. The packaging building 6 is outside the containment a and communicates via an air lock (not shown).
~23~3 The ruffling floor level it designated 9 in Figure 1, and it provided with rails 10 for the reactor refueling machine (already removed to run on.
Figures 3-5 show the reactor with a handling machine 11 in poaltlon. The machine 11 consists of a gantry 12 with wheel 13 funning on the acid rails 10, and a carriage I able to move angularly relative to the gantry 12 on a rail 15 on the gantry 12 (see particular Figures 4 and 5). The carriage 14 carries on a platform 14' movable linearly on the carriage 14 a mast 16 able to be extended and made shorter relative to the carriage 14 in a direction parallel to the axis of the reactor pressure vessel 3. There is a manipulator 17 mounted on the lower end of the mast 16 and movable in an angular and linear manner relative thereto, the manipulator 17 being capable of carrying cutting and the like tools 18 by mean of which the pressure vessel 3 and vessel internals may be dismantled prior to transfer for packaging. The mast 16 can be extended or made shorter by adding or taking away separate auctions provided with appropriate secure fastening expedients (not shown) of conventional kind.
A ring girder 19 carried by the reactor concrete structure 20 provides a track for a slew beam 21 to be rotated about the vessel center line and in one angular po~ltlon to be aligned and reglatered with fixed beams 22, 23. The beam 22 is an intermediate between the beam 21 and another slew beam 24 rotatable about the center by ~L~Z3~33 fine of that heat exchanger housing 4 which is used as the temporary repository 5. The beam 23 it a fixed beam extending into another heat exchanger housing 4, designated 25 and employed as a maintenance cell. There are for example two hoists 26, 27 movable along the beams 21, 22, 23, 24, the hoist 26 operating normally over the vessel 3 and movable into the cell 25, and the hoist 21 being normally situated over the repository 5 and on the clew beam 24 but being movable from the beam lo 24 to the beam 21 via the beam 22 and vice versa for transfer of material between the area of vessel 3 and the repository 5. There it soother fixed beam 28 with which beam 24 can be aligned and registered and which extends between repository 5 and another of the empty heat exchanger housings 4, this being designated 29 and employed for temporary waste storage. The hoist 27 can be made to travel from beam 24 to beam 28 and vice versa.
There 18 remotely controlled mechanism provided (not shown) for controlling and rotating the beams 21, I and for moving and operating the hoists 26, 27.
It 18 envisaged that the manipulator 17 and tools 18 are to be employed to cut the material of the pressure vessel into manageably-sized pieces, and that the hoist 26 with the aid of conventional gripping or possibly magnetic ].iftlng means on the end of the hoist cable (none shown), be used to transfer the pieces when cut to the repository 5 and thence to the packaging building 6 I' ~Z3~3 or to the temporary storage area 29. Furthermore, the hoist 26 would be used to pick up and transfer dismantled moderator blocks piecemeal to 5, 6 or 29.
In order to permit short-term access to the gantry S 12, carriage 14 and the upper area occupied by these components, and to obviate undue exposure of the component to radiation from vessel 3 and the vessel internals, rotatable shielding 30 with an eccentrically deposed removable shield circle 31 is provided to span the ring girder 20 (see Figures 3 and 4), the mast 16 being extendible, and the hoist 26 being operable, through the hole provided in the shielding 30 suitably rotated, when the circle 31 it removed. Figure 5 shows the mast 16 in its extended position with the manipulator 17 and tool I in position for attacking the material of vessel 3, whereas Figure 3 shows the mast 16, manipulator 17 and tool 18 in retracted position.
In an alternstlve construction, illustrated in Figures 6, 7 and 8, the handling machine if' has a 20 gantry 12 similar to the gantry 12 of the Figures 3-5 construction, with wheels 13 able to run on the existing falls 10 on the reactor charge face 9. A carriage 32 is mounted on the gantry 12 for cross-tra~el thereon.
mat 16 similar to the mat 16 of the Figures 3-5 construction is mounted on the carriage 32 and carries, a in the Figure 3-5 construction, a manipulator 17 capable of holding a tool 18.
AYE
isle The main difference from the Figures 3-S
construction 18 that there 18 a beam 33 radially mounted on a collar 34 rotatable on the mast 16. The beam 33 can be rotated by remote control of the collar 34 and can be made to align and register with an intermediate beam 22 or with a fixed beam 23, as was the beam 21 in the Figures 3-5 construction, except that, in this cave, alternative but not simultaneous registration 19 only possible. There is a slew beam 24 and fixed beam 28 as in the Figures 3-5 construction, and a hoist 27 operates between vessel 3 space and repository 5 or storage I
hoist 26 operates on beam 33 and can move on to beam 23 to operate in maintenance cell 25 or on to beam 24 via beam 22 to operate in cell 5. As in the Figures 3-5 construction, the mast 16 can be extended and shortened by adding or subtracting section.
The construction shown in Figures 9 and 10 provides a handling machine 11' which combines the slew beam 21 construction shown in Figures 3-5 with the gantry 12 and cross-travel carriage 32 of the Figures 6-8 construction, but is varied by having a telescopic mast 35 mounted on a platform 36 on the carriage 32 and having equipment, diagrammatically indicated as a windlass 37 and cable 38, for controlling the telescoping and untelescoping of the sections 39 of the mast 35.
In a modification, not illustrated, the slew beam 21 of the Figures 3-5 construction can, instead of being , I
~3~lS3 mounted on the separate ring girder 20 on the reactor building, be suspended rigidly from the rotatable carriage 14 of that construction, and be rotatable by virtue of the controlled rotation of that carriage 14 on the gantry 12, the beam corresponding to slew beam 21 thereby having its loading transferred to the falls 10 via the wheels 13 of gantry 12.
In another modification, not illustrated, the mast may be a rigid structure, and the elevation of the manipulator and tooting mounted thereon can be varied by providing means, operable remotely, for raising and towering the carriage relative to the gantry, whose elevation 18 fixed by being mounted on the said rails.
If desired, the manipulator may be mounted on an elevatable platform.
It will be appreciated that suitable biological shielding may be installed as and where necessary. For example, as floor mounted retractable shielding, and on the gantry itself, and for a maintenance cell beneath the gantry.
13~47
Claims (9)
1. A machine for dismantling, unloading and transferring to a disposal facility, nuclear reactor structure, including components which have been irradiated during operation of the reactor, the machine comprising:
a. a vertically extending mast of adjustable longitudinal extent;
b. means supporting the mast from a rigid, undismantled part of the reactor whereby the mast extends into a pressure vessel of the reactor located beneath said supporting means;
c. means for moving the mast transversely of its longitudinal axis whereby the mast can be moved into different positions within the interior of said pressure vessel;
d. a manipulator mounted on the mast for movement relative thereto and for supporting and operating a variety of tools for effecting dismantling of said structure;
e. a movable beam mounted beneath said supporting means and above the pressure vessel, said beam extending transversely of the mast and being movable angularly in a horizontal plane over an area encompassing the range of said transverse movement of the mast;
f. hoist means mounted for traverse along said beam and extendable into said pressure vessel for lifting parts of the pressure vessel after such parts have been prepared for dismantling by said tool-supporting manipulator; and g. at least one fixed beam mounted in the same horizontal plane as said movable beam for registration with the movable beam when the latter is in a predetermined angular orientation, said fixed beam when so registered forming a continuation of the movable beam whereby the hoist can be transferred from the movable beam on to the fixed beam and traversed to an unloading station.
a. a vertically extending mast of adjustable longitudinal extent;
b. means supporting the mast from a rigid, undismantled part of the reactor whereby the mast extends into a pressure vessel of the reactor located beneath said supporting means;
c. means for moving the mast transversely of its longitudinal axis whereby the mast can be moved into different positions within the interior of said pressure vessel;
d. a manipulator mounted on the mast for movement relative thereto and for supporting and operating a variety of tools for effecting dismantling of said structure;
e. a movable beam mounted beneath said supporting means and above the pressure vessel, said beam extending transversely of the mast and being movable angularly in a horizontal plane over an area encompassing the range of said transverse movement of the mast;
f. hoist means mounted for traverse along said beam and extendable into said pressure vessel for lifting parts of the pressure vessel after such parts have been prepared for dismantling by said tool-supporting manipulator; and g. at least one fixed beam mounted in the same horizontal plane as said movable beam for registration with the movable beam when the latter is in a predetermined angular orientation, said fixed beam when so registered forming a continuation of the movable beam whereby the hoist can be transferred from the movable beam on to the fixed beam and traversed to an unloading station.
2. A machine as claimed in Claim 1 in which said movable beam is mounted on a ring girder secured to the reactor structure to enable the movable beam to be rotated about the centre line of said pressure vessel.
3. A machine as claimed in Claim 1 in which said movable beam is mounted on the mast.
4. A machine as claimed in Claim 1 in which said supporting means includes structure rotatable about a vertical axis whereby the mast can be moved along an arc-shaped path within said pressure vessel.
5. machine as claimed in Claim 4 including a radiation shield mounted for rotation above said movable beam, said radiation shield including an eccentrically-disposed entry opening through which the mast and said tool-carrying manipulator pass when the mast is extended into said pressure vessel, the mast being retractable in its entirety through said opening together with said manipulator and said radiation shield including a removable section for insertion into said entry opening when the mast is so retracted.
6. A machine as claimed in Claim 5 in which the upper part of the mast is located above said radiation shield.
7. A machine as claimed in Claim 1 in which the mast comprises an assembly of sections arranged so that sections can be added to and removed from the assembly to extend and retract the mast respectively.
8. A machine as claimed in Claim 1 in which the mast is of telescopic construction.
9. A machine for dismantling, unloading and transferring to a disposal facility, nuclear reactor structure, including components which have been irradiated during operation of the 'reactor, the machine comprising:
a. a gantry;
b. means mounting the gantry on a rigid, undismantled part of the reactor;
c. a carriage mounted on the gantry for rotation about a vertical axis;
d. a platform mounted on the carriage for movement diametrally thereof;
e. a vertically extending mast of adjustable longitudinal extent supported by said platform whereby the mast extends into a pressure vessel of the reactor located beneath said gantry, said gantry, carriage and platform serving to move the mast transversely of its longitudinal axis whereby the mast can be moved into different positions within the interior of said pressure vessel;
f. a manipulator mounted on the mast for movement relative thereto and for supporting and operating a variety of tools for effecting dismantling of said structure;
g. a radiation shield mounted for rotation beneath said carriage and platform, said shield including an eccentrically disposed entry opening through which the mast passes when extended into the pressure vessel, the mast being retractable in its entirety through said opening together with said manipulator and the shield including a removable closure section for insertion into said opening when the mast is so retracted;
h. a movable beam mounted beneath said radiation shield and above the pressure vessel, said beam extending transversely of the mast and being movable angularly in a horizontal plane over an area encompassing the range of said transverse movement of the mast;
i. hoist means mounted for traverse along said beam and extendable into said pressure vessel for lifting parts of the pressure vessel after such parts have been prepared for dismantling by said tool-supporting manipulator; and j. at least one fixed beam mounted in the same horizontal plane as said movable beam for registration with the movable beam when the latter is in a predetermined angular orientation, said fixed beam when so registered forming a continuation of the movable beam whereby the hoist can be transferred from the movable beam onto the fixed beam and traversed to an unloading station.
a. a gantry;
b. means mounting the gantry on a rigid, undismantled part of the reactor;
c. a carriage mounted on the gantry for rotation about a vertical axis;
d. a platform mounted on the carriage for movement diametrally thereof;
e. a vertically extending mast of adjustable longitudinal extent supported by said platform whereby the mast extends into a pressure vessel of the reactor located beneath said gantry, said gantry, carriage and platform serving to move the mast transversely of its longitudinal axis whereby the mast can be moved into different positions within the interior of said pressure vessel;
f. a manipulator mounted on the mast for movement relative thereto and for supporting and operating a variety of tools for effecting dismantling of said structure;
g. a radiation shield mounted for rotation beneath said carriage and platform, said shield including an eccentrically disposed entry opening through which the mast passes when extended into the pressure vessel, the mast being retractable in its entirety through said opening together with said manipulator and the shield including a removable closure section for insertion into said opening when the mast is so retracted;
h. a movable beam mounted beneath said radiation shield and above the pressure vessel, said beam extending transversely of the mast and being movable angularly in a horizontal plane over an area encompassing the range of said transverse movement of the mast;
i. hoist means mounted for traverse along said beam and extendable into said pressure vessel for lifting parts of the pressure vessel after such parts have been prepared for dismantling by said tool-supporting manipulator; and j. at least one fixed beam mounted in the same horizontal plane as said movable beam for registration with the movable beam when the latter is in a predetermined angular orientation, said fixed beam when so registered forming a continuation of the movable beam whereby the hoist can be transferred from the movable beam onto the fixed beam and traversed to an unloading station.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000478533A CA1223983A (en) | 1985-04-09 | 1985-04-09 | Machines for dismantling decommissioned nuclear reactors |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000478533A CA1223983A (en) | 1985-04-09 | 1985-04-09 | Machines for dismantling decommissioned nuclear reactors |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1223983A true CA1223983A (en) | 1987-07-07 |
Family
ID=4130206
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000478533A Expired CA1223983A (en) | 1985-04-09 | 1985-04-09 | Machines for dismantling decommissioned nuclear reactors |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1223983A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023159299A1 (en) * | 2022-02-28 | 2023-08-31 | Ats Corporation | Systems, tools and methods for disassembling and segmenting a calandria nuclear reactor |
-
1985
- 1985-04-09 CA CA000478533A patent/CA1223983A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023159299A1 (en) * | 2022-02-28 | 2023-08-31 | Ats Corporation | Systems, tools and methods for disassembling and segmenting a calandria nuclear reactor |
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| MKEX | Expiry |