Method for internal inspection of a pressurized water nuclear reactor pressure vessel
AssigneeWestinghouse Electric Corp.
InventorsDavid E. Boyle, Edward J. Rusnica
Life of this patent
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Abstract
An inservice inspection of a surface area or welds of a nuclear reactor pressure vessel is carried out, without the need to remove the core barrel and lower internals therefrom, by providing access to the annular chamber between the core barrel and the pressure vessel wall through an aperture in the upper flange of the core barrel. An inspection means, such as an ultrasonic testing device is inserted into the annular chamber through the access and positioned proximate the weld to be inspected and inspection of the weld effected by the device.
Claims11
A method for inservice inspection of a predetermined area of the wall of a pressurized water nuclear reactor pressure vessel wherein said nuclear reactor has a substantially cylindrical pressure vessel wall, with a plurality of inlet and outlet nozzles therein, and a generally cylindrical vertically oriented core barrel having an upper flange disposed within said pressure vessel, with an annular chamber formed between said pressure vessel wall and said barrel, said upper flange resting upon a ledge about the inner periphery of the upper section of said pressure vessel wall, comprising:
- providing access to said annular chamber through the flange of said core barrel, while said core barrel is disposed within said pressure vessel;
- inserting a means for inspecting said predetermined area through said access;
- positioning said inspecting means in proximity to said predetermined area of said pressure vessel wall to be inspected;
- and
- inspecting said predetermined area by said inspecting means while said barrel remains disposed within said pressure vessel.
A method for inservice inspection of predetermined welds present in the wall of a pressurized water nuclear reactor pressure vessel wherein said nuclear reactor has a substantially cylindrical pressure vessel wall, with a plurality of inlet and outlet nozzles therein, and a generally cylindrical, vertically oriented core barrel having an upper flange disposed within said pressure vessel, with an annular chamber formed between said pressure vessel wall and said barrel, said upper flange resting upon a ledge about the inner periphery of the upper section of said pressure vessel wall, comprising:
- providing access to said annular chamber through the flange of said core barrel, while said core barrel is disposed within said pressure vessel, and wherein the upper flange of said core barrel has a plurality of apertures therethrough which communicate with said annular chamber and a removable plug within each said aperture, by removing at least one of said plugs;
- inserting a means for inspecting a weld, present in the wall of the pressure vessel, through said aperture with said plug removed;
- positioning said inspecting means in proximity to said weld in said pressure vessel wall to be inspected;
- and
- inspecting said weld by said inspecting means while said barrel remains disposed within said pressure vessel.
Dependencies are inferred from the claim text.