Machines for dismantling decommissioned nuclear reactors

Claim 2

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.

Claim 3

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.

Claim 4

A machine a claimed in claim 1 in which said movable beam is mounted on the mast.

Claim 5

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.

Claim 6

A machine as claimed in clain 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 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.

Claim 7

A machine as claimed in claim 5 in which the upper part of the mast is located above said radiation shield.

Claim 8

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.

Claim 9

A machine as claimed in claim 1 in which the mast is of telescopic construction.

Claim 10

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, th 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.

Claim 11

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, th 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.