Abstract: A holding fixture for assisting in assembly of a support grid for nuclear fuel rods and including a plurality of straps each having a plurality of slots extending approximately half a height of the straps and tabs formed beside or between the slots. The holding fixture includes an actuation plate, a support plate having a plurality of receiving members structured to receive therein straps of the support grid and having a plurality of cells, and a plurality of cam assemblies structured to move to deflect every other tab of the straps received in the plurality of receiving members. The cam assemblies are disposed in every other cell of the support plate.

Abstract: A supercritical carbon dioxide power generation Brayton cycle system and method that employs an alternate heat recuperation method and apparatus that utilizes switched banks of bead filled tanks to accumulate and recover the thermal energy of the two streams of working fluid in such a way that the variable thermal properties of the supercritical carbon dioxide can be accommodated without significant loss of thermal efficiency.

Abstract: A thermal actuator for a rotating shaft shutdown seal that has a piston with a portion of its axial length enclosed within a chamber shell with a material that expands upon a rise in temperature. The portion of the actual length of the piston within the chamber has at least two different diameters with the larger diameter leading in the direction of travel of the piston. Upon a rise in temperature, expansion of the material surrounding the piston within the chamber creates a force on the piston in the desired direction of travel. Below a preselected temperature the piston is positively locked with a passive release when the preselected temperature is reached.

Abstract: An electrochemical machining apparatus is modular and includes a power module, an electrolyte processing module, an actuator module, and a control module that are connected with one another via a connection apparatus. The components are modular and are mounted on separate supports, many of which additionally include caster, and the connection apparatus is in the form of a removable umbilical. The modules can be individually moved to a location within a facility where a component is installed, and the modules can be interconnected to form the modular electrochemical machining apparatus at the location of the installed component. The apparatus can then perform an electrochemical machining operation in situ on the installed component.

Abstract: A delivery device that is usable in a laser peening operation emits a columnar flow of a fluid that contains therein a beam of electromagnetic energy. The beam is retained within the interior of the flow of fluid since the total internal reflectivity of the flow is sufficient to do so. The flow of fluid that serves as a conduit for the beam also itself impinges on a workpiece and thus contains and washes away the plasma that forms from a laser peening operation, and this resists the plasma from reaching and possibly damaging the delivery device. The carrying of the beam in the columnar flow of fluid avoids the need to maintain a fixed distance between the delivery device and the workpiece, which simplifies the movement by a robotic manipulator of the delivery device along a non-planar surface of a workpiece during a laser peening operation.

Abstract: A delivery system for remotely driving an eddy current probe through the tubing of a heat exchanger. The system uses a flexible shaft and air pressure to move an inspection probe through the heat exchanger tubes. The flexible shaft initially drives the probe through a sealed conduit to deliver the probe to the tube end at which point a seal on the shaft near the probe head contacts the tube inner surface allowing a buildup of air pressure behind the seal, thus driving the probe through the tube.

Abstract: A supercritical carbon dioxide power generation Brayton cycle system and method that employs an alternate heat recuperation method and apparatus that utilizes switched banks of bead filled tanks to accumulate and recover the thermal energy of the two streams of working fluid in such a way that the variable thermal properties of the supercritical carbon dioxide can be accommodated without significant loss of thermal efficiency.

Abstract: A probe for transporting a nondestructive inspection sensor through a tube, that employs wheels to reduce friction. The radial travel of the wheels are mechanically linked through a cam and axially reciprocal plunger arrangement that centers the probe at tube diameter transitions. Internal wire bending is minimized and a dynamic seal is provided to facilitate an insertion force at the probe and reduce or eliminate compressive load buckling of the flexible cable carried by the probe. Like the wheel arrangement, radial travel of the seal segments are mechanically linked to provide probe centering.

Abstract: A delivery system for remotely driving an eddy current probe through the tubing of a heat exchanger. The system uses a flexible shaft and air pressure to move an inspection probe through the heat exchanger tubes. The flexible shaft initially drives the probe through a sealed conduit to deliver the probe to the tube end at which point a seal on the shaft near the probe head contacts the tube inner surface allowing a buildup of air pressure behind the seal, thus driving the probe through the tube.

Abstract: A thermal actuator for a rotating shaft shutdown seal that has a piston with a portion of its axial length enclosed within a chamber shell with a material that expands upon a rise in temperature. The portion of the actual length of the piston within the chamber has at least two different diameters with the larger diameter leading in the direction of travel of the piston. Upon a rise in temperature, expansion of the material surrounding the piston within the chamber creates a force on the piston in the desired direction of travel. Below a preselected temperature the piston is positively locked with a passive release when the preselected temperature is reached.

Abstract: A delivery system for remotely driving an eddy current probe through the tubing of a heat exchanger. The system uses a flexible shaft and air pressure to move an inspection probe through the heat exchanger tubes. The flexible shaft initially drives the probe through a sealed conduit to deliver the probe to the tube end at which point a seal on the shaft near the probe head contacts the tube inner surface allowing a buildup of air pressure behind the seal, thus driving the probe through the tube.

Abstract: A thermal actuator for a rotating shaft shutdown seal that has a piston with a portion of its axial length enclosed within a cylinder shell with a material, such as a fusible link that changes state or deforms above a given temperature, interposed between a closed end of the cylinder and one end of the piston. The piston is spring biased toward the material and moves toward the closed end of the cylinder when the given temperature is reached and the deformation or change of state of the material makes room for the piston to move toward the closed end. Movement of the piston is transferred through a piston rod to activate the seal.

Abstract: A thermal actuator for a rotating shaft shutdown seal that has a piston with a portion of its axial length enclosed within a cylinder shell with a material, such as a fusible link that changes state or deforms above a given temperature, interposed between a closed end of the cylinder and one end of the piston. The piston is spring biased toward the material and moves toward the closed end of the cylinder when the given temperature is reached and the deformation or change of state of the material makes room for the piston to move toward the closed end. Movement of the piston is transferred through a piston rod to activate the seal.

Abstract: A tubesheet anchor for suspending a tool from the underside of a heat exchanger tubesheet that inserts one end of two fingers into corresponding openings in the tubesheet and leverages one finger off the other to apply a frictional force to the sides of the tubesheet openings in which the fingers are inserted to clamp the fingers to the tubesheet.

Abstract: A robotic tubesheet walker having two rails connected by a central hinge, wherein the central hinge can be opened or closed by an actuation device. Upon each rail is mounted a carriage, wherein each carriage can move along its respective rail toward or away from the central hinge by means of a drive mechanism. Each carriage further contains at least two “gripper” attachment mechanisms, such as camlocks, to grip the tubesheet. The grippers either insert into tube holes within the tubesheet to fasten the respective carriage to the tubesheet, or retract to disengage. Further attached to the central hinge is a tool support fixture, and attached to the tool support fixture is a coupler that holds maintenance or inspection tools.

Abstract: A delivery system for remotely driving an eddy current probe through the tubing of a heat exchanger. The system uses a flexible shaft and air pressure to move an inspection probe through the heat exchanger tubes. The flexible shaft initially drives the probe through a sealed conduit to deliver the probe to the tube end at which point a seal on the shaft near the probe head contacts the tube inner surface allowing a buildup of air pressure behind the seal, thus driving the probe through the tube.

Abstract: A method of and apparatus for securing tubes within a steam generator against vibration with a metallic anti-vibration bar in a tube bundle. The tube bundle has a plurality of tubes, arranged in rows and columns, with lanes between the tube columns. The method comprises the steps of: inserting the anti-vibration bar in the tube bundle; plastically expanding the wall of the anti-vibration bar from an unexpanded position to an expanded position. In the unexpanded position there are a plurality of gaps between the anti-vibration bar and the tubes of the tube bundle. The gaps decrease in size as the wall of the anti-vibration bar moves from the unexpanded position to the expanded position.

Abstract: A robotic tubesheet walker having two rails connected by a central hinge, wherein the central hinge can be opened or closed by an actuation device. Upon each rail is mounted a carriage, wherein each carriage can move along its respective rail toward or away from the central hinge by means of a drive mechanism. Each carriage further contains at least two “gripper” attachment mechanisms, such as camlocks, to grip the tubesheet. The grippers either insert into tube holes within the tubesheet to fasten the respective carriage to the tubesheet, or retract to disengage. Further attached to the central hinge is a tool support fixture, and attached to the tool support fixture is a coupler that holds maintenance or inspection tools.

Abstract: An eddy current probe for inspecting steam generator tubing, that has radially outwardly biased rollers that function to center the probe within the tubing and reduce friction as the probe moves along the interior of the steam generator heat exchanger tube walls. The rollers may include a braking system which controls the drag on the rollers and thus the speed of the probe along the tubing. The direction of travel of the rollers is remotely adjustable to control the inspection pattern and the force of the rollers against the interior surface of the tubing can be remotely controlled.

Abstract: Apparatus and a method to inspect tubing by means of a free flying, autonomous inspection head that is not attached by wires to external control and data acquisition equipment. The inspection head travels through the tube with an attached module that integrates all the necessary support for the electronic and mechanical control of a nondestructive sensor within the inspection head.