Abstract: A locking ring holds a control rod drive housing tube of a nuclear power plant when a pressure chamber having a contact wall is pressurized. The contact wall faces the control rod drive housing tube presses against it when the pressure chamber is pressurized. The locking ring can lock a threaded nut after it has been screwed onto the control rod drive housing tube. In a method for securing a threaded nut of a control rod drive housing tube of a nuclear power plant in the vicinity of the threaded nut, a body is attached to the control rod drive housing tube, as a result of a contact surface of the body engaging the control rod drive housing tube. A contact surface of the pressure chamber is pressed onto the control rod drive housing tube when the pressure chamber is pressurized.

Abstract: A self-propelled inspection vehicle for piping systems includes a vehicle body in the form of a rigid, tightly-sealed housing having forward and rearward end faces as seen in a given insertion direction of the vehicle into the piping, a power supply disposed in the housing, a propulsion mechanism for resiliently bracing the housing against the inner surface of the piping, at least one motor connected to the power supply and to the propulsion mechanism for driving the propulsion mechanism, a television camera optical system having a given field of view being supported on the forward end face of the housing, and at least one light source associated with the given field of view being supported on the forward end face of the housing.

Abstract: A manipulator head for the remotely controlled positioning and operation of a tool in the interior of a pipe includes:first support flanges having guiding elements and clamping devices;a tubular tool holder frame having second support flanges interconnecting the first support flanges and being rotatably supported thereby;a rotating tool including a milling cutter at an assembly opening in the tool holder for machining the inner wall surface of a pipe;a first guide rail attached to the inner wall surface of the tool holder, a first slide axially movable on the first guide rail, a first driving device coupled to the first slide for axially moving the tool;a second guide rail fastened to the first slide, a second slide radially movable on the second guide rail, a second driving device coupled to the second slide for radially setting the tool;the milling cutter being fastened to the second slide, a third driving device coupled to the milling cutter for a working motion of the tool; anda fourth driving device disp

Abstract: A manipulator head for the remote-controlled positioning and operation of a grinding device within a pipe, which includes two support flanges having clamping devices and guide elements for extending the manipulator head; a frame rotatably mounted in the support flanges; a grinding device, fastened to the frame, with a drive and bearing member for a grinding tool, a drive device for axially adjusting the grinding device, and a feed device for radially fine-feeding the grinding tool, a motor for rotating the frame relative to the support flanges; feed line connections of the drive devices disposed on only one of the support flanges; the frame formed of two bearing flanges clamped together by spacer sleeves and clamping bolts; a base carriage guided on the spacer sleeves to travel axially to the manipulator head; a support carriage mounted on the base carriage and carring the drive motor for the grinding tool; a base plate secured, in parallel with the support flange, to the support carriage; the grinding tool c