Abstract: A welding apparatus for internally welding sleeves to tubes comprises a central shaft with an electrode attached thereto which are capable of being inserted in a tubular member. A plurality of remotely actuable seals are disposed on the welding apparatus and around the electrode for establishing a sealed chamber in the sleeve in which the welding may take place. The welding apparatus is capable of supplying an inert shielding gas to the sealed chamber for pressurizing the sealed chamber during the welding process and while the electrode completes a weld around the inner circumference of the sleeve. The apparatus may also be used to internally braze the sleeve to the tube.

Abstract: A welding apparatus for internally welding sleeves to tubes comprises a central shaft with an electrode attached thereto which are capable of being inserted in a tubular member. A plurality of remotely actuable seals are disposed on the welding apparatus and around the electrode for establishing a sealed chamber in the sleeve in which the welding may take place. The welding apparatus is capable of supplying an inert shielding gas to the sealed chamber for pressurizing the sealed chamber during the welding process and while the electrode completes a weld around the inner circumference of the sleeve. The apparatus may also be used to internally braze the sleeve to the tube.

Abstract: A robotic manipulator wrist has one part 10 rotatable relative to the other part 12 of the wrist, and gear trains 16, 18, 20, operates to rotate the end effector shaft 14 when a brake 36 is applied to prevent relative movement between the two parts 10 and 12, and to rotate one part 10 relative to the other part 12 when a second brake 38 is applied to prevent relative movement between the end effector gear 18 and the intermediate gear 16.

Abstract: A segmented manipulator arm for a nuclear reactor vessel inspection device is disclosed. The several segments of the arm are linked in a manner which permits independent movement of each segment in a different plane of motion. The transducer array which is utilized to conduct the examination of any appropriate point in the reactor vessel is cooperably linked to the final or most forward segment of the manipulator arm.The first segment of the manipulator arm is appropriately coupled to the main column of the inspection device for independent movement in one of three planes relative to the main column. Additional segments are employed and cooperatively linked to the first segment to yield a total of nine planes of movement for one or more of the segments. In addition, brackets are used to constrain segment movement in parallel or predetermined planes as desired.

Abstract: An emergency disconnect means is disclosed for uncoupling a portion of the linkage means which connects the several segments of an articulating manipulator arm employed in a nuclear reactor vessel inspection device. One of the motor housings included in the manipulator arm's segmented drive train is pivotably coupled between two segments thereof. In the event of power failure or the necessity of manual retraction of the manipulator arm from within the vessel, a lever is manually operated and moved from its normally locked position wherein the motor housing is positionally fixed to a release position wherein the motor housing and the remainder of the manipulator arm segments connected forwardly thereof are pivotally released to shorten the normal arm reach and alter the normal orientation of the manipulator arm to expedite removal without danger of collision.

Abstract: An emergency retraction means is provided for removing the extended manipulator arm of a nuclear reactor vessel inspection device from within a nozzle thereof or from a fully extended position should power for normal extension drive fail. A cable is looped about the interior of a carriage assembly which drivingly engages the remainder of the manipulator arm. The cable is fixedly clamped at one location within the carriage assembly and looped about a first idler pulley mounted in the manipulator arm and is guided therefrom by another idler to an accessible point where the end of the cable is formed into a ring. The ring is detachably secured thereat to the carriage assembly.When an emergency occurs, a hook is lowered to engage the ring and is then lifted to detach it from the carriage assembly and move it upwardly therefrom.