Apparatus for reconditioning a heavy workpiece and method

Abstract

A method for the in-situ reconditioning of a heavy workpiece mounted on the floor. The method comprises assembling a jig mounted on the floor so as to be arranged around the workpiece to be reconditioned, that is also mounted on the floor, the jig supporting a gantry at the two ends of same, on which there is mounted a precision robotic arm carrying at least one machining apparatus. The method also comprises the alignment of the workpiece and the jig using a precision laser alignment tool in order to allow the jig, the gantry and the robotic arm to form a precision machining apparatus. The method also comprises the reconditioning of the workpiece using the precision machining apparatus.

1 . A method for the in-situ reconditioning of a heavy workpiece mounted on a floor, the method characterized in that it comprises:
 assembling a jig mounted on said floor to be placed in the vicinity of said workpiece to recondition, also mounted on said floor, said jig supporting a frame on which is mounted a precision robotic arm carrying at least one machining unit;   aligning said workpiece and said jig with a laser precision alignment tool to allow said jig, said mount and said robotic arm to form a precision machining apparatus; and   machining said workpiece using said precision machining apparatus.   
     
     
         2 . The method of  claim 1 , characterized in that said assembly of said jig is performed such that said jig is arranged around said workpiece to be reconditioned, said frame comprising a gantry, and said jig supporting said gantry at both ends. 
     
     
         3 . The method of  claim 2 , characterized in that said jig is configured such that a portion of said jig moves relative to said floor, said reconditioning comprising moving said portion of said jig relative to said floor. 
     
     
         4 . The method of  claim 3 , characterized in that said moving of said portion of said jig is performed by means of a precision system of bearing-supported roller pinions which engages with a rack joined to said jig. 
     
     
         5 . The method of  claim 3  or  4 , characterized in that said jig comprises a central stilt and an annular turntable centered around said center stilt, said assembling step comprising placing said workpiece around said central stilt, and said gantry supported at one of said two ends on said central stilt and at the other of its said two ends on said turntable. 
     
     
         6 . The method of  claim 5 , characterized in that said annular turntable comprises segments forming two superposed rings, said assembling comprising placing and assembling said segments forming said two superposed rings around said workpiece. 
     
     
         7 . The method according to one of  claim 5  or  6 , characterized in that said assembling comprises positioning of said turntable and said workpiece such that said turntable and said workpiece are concentric. 
     
     
         8 . The method as claimed in any one of the preceding claims, characterized in that said method comprises, prior to said assembling, positioning stilts on the floor using a precision laser alignment tool and adjusting height of said stilts using a precision laser alignment tool, said stilts positioned to receive said workpiece and said jig. 
     
     
         9 . The method of  claim 8 , characterized in that said assembling comprises bolting said stilts to the floor. 
     
     
         10 . The method according to  claim 8  or  9 , characterized in that said method comprises adjusting said stilts with a precision laser alignment tool once said stilts have received said workpiece and said jig in order to compensate for deformation of floor on which are placed said stilts which received said workpiece and said jig. 
     
     
         11 . The method according to any one of  claims 8  to  10 , characterized in that said assembling comprises the use of wedges between said stilts and said jig and between said stilts and said workpiece to minimize the wear of said stilts during reconditioning. 
     
     
         12 . The method as claimed in any one of the preceding claims, characterized in that said precision robotic arm carries a welding tool adapted to add metal to said workpiece. 
     
     
         13 . A method of producing renewable electricity through an electricity generation system consisting of heavy parts used in said electricity generation system, said electricity producing method characterized by comprising.
 producing electricity;   determining whether one of said parts of the electricity generation system requires reconditioning;   reconditioning said one of said parts according to the in-situ reconditioning method of any of  claims 1  to  12 ; and   resumption of producing electricity.   
     
     
         14 . The method according to  claim 13 , characterized in that it is a method of producing hydroelectricity, said electricity generation system is a hydroelectric power plant, and said part is a part of a hydraulic turbine. 
     
     
         15 . The method according to  claim 13  or  14 , characterized in that said reconditioning of said one of said parts is the reconditioning of either:
 a Francis type mobile wheel; 
 a Kaplan type mobile wheel; 
 a wicket gate; 
 a draft tube; 
 an alternator; 
 a runner blade; 
 a bottom floor; 
 an upper floor; 
 a crown; 
 a shaft; or 
 a gate opening ring. 
 
     
     
         16 . A precision reconditioning apparatus of a heavy workpiece mounted on a floor, said apparatus characterized in that it comprises:
 a jig comprising:
 a central stilt; and 
 an annular turntable centered around said central stilt; 
   a gantry with two ends configured to be supported at one of said two ends on said central stilt and the other of its said two ends on said turntable; and   a robotic arm mountable on said gantry, said robotic arm configured to receive a machining apparatus for readjusting said heavy workpiece.   
     
     
         17 . The apparatus according to  claim 16 , characterized in that said robotic arm comprises at least one machining apparatus. 
     
     
         18 . The apparatus according to  claim 17 , characterized in that said at least one machining apparatus comprises a welding tool adapted to add metal to said workpiece. 
     
     
         19 . The apparatus according to any of the claims of  claims 16  to  18 , characterized in that said turntable comprises a fixed portion and a movable portion, said fixed portion being connected to said movable portion by a precision rolling system. 
     
     
         20 . The apparatus according to  claim 19 , characterized in that said precision rolling system is a precision system of bearing-supported roller pinions which engages with a rack joined to said jig. 
     
     
         21 . The apparatus of any of  claims 16  to  20 , characterized in that said apparatus comprises at least three height-adjustable stilts for receiving said turntable to enable said turntable to be leveled. 
     
     
         22 . The apparatus of  claim 21 , characterized in that each of said height-adjustable stilts for receiving said turntable comprises a wedge configured to be positioned between said turntable and said each of said stilts for receiving said turntable. 
     
     
         23 . The apparatus of any one of  claims 16  to  22 , characterized in that said apparatus comprises at least three height-adjustable stilts for receiving said heavy workpiece and for enabling said heavy workpiece to be leveled. 
     
     
         24 . The apparatus according to  claim 23 , characterized in that each of said height-adjustable stilts to receive said heavy workpiece include a wedge configured to be placed between said heavy workpiece and said each of said stilts to receive said heavy workpiece. 
     
     
         25 . The apparatus according to any one of  claims 16  to  24 , characterized in that said turntable is composed of an assembly of arc-shaped segments. 
     
     
         26 . A robotic jig used for the machining or precision reconditioning of a heavy workpiece mounted to the floor, the jig characterized in that it comprises:
 An annular turntable composed of an assembly of arc-shaped segments to constitute a fixed portion and a movable portion, said fixed portion being connected to said movable portion by a precision rolling system, said turntable being capable of surrounding said heavy workpiece mounted on the floor;   at least three height-adjustable stilts to enable said turntable to be leveled; and   a precision displacement system comprising said precision rolling system for moving said movable portion relative to said fixed portion of the turntable.   
     
     
         27 . The jig according to  claim 26 , characterized in that it comprises a mount for a robotic tool on said movable portion allowing said tool to access said heavy workpiece mounted to the floor from all sides. 
     
     
         28 . The jig according to  claim 27 , characterized in that said mount comprises a gantry having two ends, said gantry supported on a first of its said two ends on said turntable. 
     
     
         29 . The jig according to  claim 28 , characterized in that said jig comprises a central stilt. 
     
     
         30 . The jig according to  claim 29 , characterized in that said gantry is supported at a second of its said two ends on the central stilt. 
     
     
         31 . The jig according to any one of  claims 26  to  30 , characterized in that said precision rolling system is a precision system of bearing-supported roller pinions which engages with a rack joined to said jig. 
     
     
         32 . The jig of any one of  claims 26  to  31 , characterized in that each of said stilts comprises a wedge configured to be placed between said turntable and said each of said stilts.