Device and method for carrying out maintenance work in a region of a plant delimited by a wall having at least two facing surfaces

Abstract

The maintenance device comprises a robot ( 2 ) for carrying out maintenance work in a remote-controlled or programmed way in the maintenance region. The robot ( 2 ) comprises a supporting part ( 2 a ) connected to a clamping support ( 3 ) secured to a means ( 4 ) of transporting the maintenance device ( 1 ) between an introductory region and the maintenance region. The clamping support ( 3 ) comprises clamping shoes ( 11, 13 a , 13 b ) which can be moved in roughly parallel and opposite directions so as to clamp the maintenance device ( 1 ) in the maintenance region. The transport means ( 4 ) may be constructed in the form of a carriage comprising two motorized wheelsets. The device and the method of the invention make it possible in particular to carry out machining or inspection work inside primary pipes of a pressurized water nuclear reactor.

1 . Method for carrying out maintenance work in a region of a plant delimited by at least one wall ( 32 ) having at least two facing surfaces between which the maintenance work is carried out and which is accessible from an introductory region ( 31 ), comprising: 
 using a remote-controlled robot ( 2 ) comprising a supporting part ( 2   a ) and at least one moving part ( 2   b ,  2   c ,  2   d ,  2   e ,  2   f ) that can move with respect to the supporting part ( 2   a ),    fixing the supporting part ( 2   a ) of the robot is fixed to a support ( 3 ) secured to a remote-controlled motorized transport carriage ( 4 ),    placing an assembly consisting of the robot ( 2 ), the support ( 3 ) and the transport carriage ( 4 ) in the introductory region ( 31 ) of the plant ( 32 ), in a position for accessing the maintenance region,    moving the motorized transport means bearing the support ( 3 ) and the robot ( 2 ) by remote control of motorized means ( 23 ) of the transport means ( 4 ), between the introductory region ( 31 ) and the maintenance region ( 37 ),    stopping the transport carriage ( 4 ) in the maintenance region ( 37 ),    operating the clamping means ( 11 ,  13   a ,  13   b ) of the support ( 3 ) secured to the transport means ( 4 ) remotely between two bearing surfaces in the maintenance region ( 37 ), and    initiating at least the start of the maintenance work in the maintenance region ( 37 ) using at least one moving part ( 2   b ,  2   c ,  2   d ,  2   e ,  2   f ) of the robot ( 2 ).    
   
   
       2 . Method according to  claim 1 , wherein the bearing surfaces for the clamping means are the two facing surfaces of the wall ( 32 ) of the region of the plant.  
   
   
       3 . Method according to  claim 1 , wherein at least one of the bearing surfaces for the clamping means ( 11 ,  13   a ,  13   b ) is a surface attached to the plant such as a surface of a support ( 40 ,  40   a ) or of a positioning hoop ( 41 ).  
   
   
       4 . Method according to  claim 1 , wherein the maintenance work in the maintenance region ( 37 ) is at least one of the following operations: machining, inspecting and welding on a surface of the plant in the maintenance region ( 37 ).  
   
   
       5 . Method according to  claim 1 , wherein the maintenance work is carried out in successive phases between which a tool ( 26 ,  28 ,  29 ,  30 ) carried by a mobile end part ( 2   f ) of the robot ( 2 ) is changed.  
   
   
       6 . Method according to  claim 1 , comprising carrying at least some of the phases of the maintenance work in a programmed way within the maintenance region ( 37 ).  
   
   
       7 . Maintenance method according to  claim 1 , for performing maintenance in a maintenance region inside a primary pipe of a pressurized water nuclear reactor, characterized in that the introductory region of the plant in which the assembly consisting of the robot ( 2 ), the support ( 3 ) and the transport carriage ( 4 ) is placed in a position for accessing the maintenance region, is a region situated inside at least one of the following: the casing ( 31 ) of a primary pump of the nuclear reactor, the nuclear reactor vessel and the water box of a steam generator.  
   
   
       8 . Maintenance method according to  claim 2 , for performing maintenance in a maintenance region inside a primary pipe of a pressurized water nuclear reactor, characterized in that the introductory region of the plant in which the assembly consisting of the robot ( 2 ), the support ( 3 ) and the transport carriage ( 4 ) is placed in a position for accessing the maintenance region, is a region situated inside at least one of the following: the casing ( 31 ) of a primary pump of the nuclear reactor, the nuclear reactor vessel and the water box of a steam generator.  
   
   
       9 . Maintenance method according to  claim 3 , for performing maintenance in a maintenance region inside a primary pipe of a pressurized water nuclear reactor, characterized in that the introductory region of the plant in which the assembly consisting of the robot ( 2 ), the support ( 3 ) and the transport carriage ( 4 ) is placed in a position for accessing the maintenance region, is a region situated inside at least one of the following: the casing ( 31 ) of a primary pump of the nuclear reactor, the nuclear reactor vessel and the water box of a steam generator.  
   
   
       10 . Maintenance method according to  claim 4 , for performing maintenance in a maintenance region inside a primary pipe of a pressurized water nuclear reactor, characterized in that the introductory region of the plant in which the assembly consisting of the robot ( 2 ), the support ( 3 ) and the transport carriage ( 4 ) is placed in a position for accessing the maintenance region, is a region situated inside at least one of the following: the casing ( 31 ) of a primary pump of the nuclear reactor, the nuclear reactor vessel and the water box of a steam generator. to be in immediate condition for allowance. Accordingly, the Examiner is respectfully requested to pass this application to issue.