| 摘要 |
The invention relates to a tool and a method for obtaining samples from the wall of a pressure tube which fits out a nuclear reactor, such as a CANDU-type reactor. According to the invention, the tool comprises a cylindrical body () which is provided with a central axis () and which comprises some carriage, drive and hydraulic regulator modules (), respectively, which are connected to one another by means of some flexible joints (), some hydraulically actuated bearing pads () being mounted to the body () while, within the carriage module () there are placed, in front of some apertures () cut therein, some cutter assemblies () in connection with some carriages () connected by means of some splined couplers () to a drive shaft () driven by an electric motor (). The method claimed by the invention consists in moving the first cutter against the internal wall of the tube and then describing a circular arc in order to cut a portion from the internal wall, moving the first cutter away from the internal wall and moving the second cutter against the first surface of the tube, followed by moving the second cutter in the shape of a circular arc in order to cut a first sample and moving the second cutter away from the first surface; further on, the third cutter is moved against the internal wall and then moved so as to describe a circular arc in order to cut a portion from the internal wall, followed by moving the third cutter away from the internal wall and moving the fourth cutter against a second surface of the tube for cutting another portion of the internal wall, finally the fourth cutter being moved so as to describe a circular arc along the second surface for cutting a second sample and then moved away from the second surface. |
