Abstract: A pellet stack length recording switch, for use in a measurement system having a movable measuring head and a measuring device for measuring a length of a nuclear fuel pellet stack segment, includes a probe for contacting and applying a compression force to an end of the pellet stack segment, a compression spring having a predetermined compression force and cooperating with the measuring head and the probe, a pin mechanism attached to the probe, and a sensor for sensing a position of the pin mechanism and outputting a position signal for triggering a measurement by the measuring device of the length of the pellet stack segment when the compression force applied by the probe is at least equal to the predetermined compression force. The probe may include a slider block, for compressing the spring, and a probe member attached to the slider block. The pin mechanism may include a trip screw for tripping the sensor.

Abstract: A capture row storage tray for holding rows of nuclear fuel pellets includes an array of laterally spaced elongated guide members extending parallel to one another, and stiffening members attached to the guide members for mounting them in the array. Pairs of adjacent guide members define elongated channels therebetween which extend parallel to one another. Each channel is open at one end for receiving a plurality of nuclear fuel pellets therethrough. The adjacent guide members of each pair have laterally spaced bottom portions attached to the stiffening members, laterally spaced and converging side portion with inclined surfaces for confining the pellets in the channel and for guiding and supporting the pellets into and at an end-to-end aligned relationship within the channel, and laterally spaced top portions which define an elongated open slot of a width less than the diameter of the pellets for capturing the pellets in the channel.

Abstract: A pellet collating system includes a tray positioning station located adjacent a pellet collating line with a tray transfer robot located therebetween. The tray positioning station has mobile carts lodged thereat, some supporting pellet supply trays and others supporting pellet storage trays. Pellets on one supply tray and later placed on one storage tray are of the same enrichment. Pellet enrichments on some trays are different from on others. The collating line includes pellet input, work and output stations arranged in tandem. The robot is operable to transfer supply and storage trays one at a time to and from the positioning station and the respective input and output stations. An input sweep head is operable for sweeping pellets onto the work station from a supply tray on the input station. A gripping and measuring head is operable for measuring a desired length of pellets on the work station and then separating the measured desired length of pellets from the remaining pellets, if any.

Abstract: A method and apparatus for passively scanning for the gamma radiation emission count of nuclear fuel contained within a nuclear fuel rod to determine enrichment uniformity are enclosed, and wherein a nuclear fuel rod containing a nuclear fuel is advanced along a linear path of travel and its natural gamma radiation emission count is repeatedly detected at each of a plurality of regularly spaced apart discrete segments along the length of the rod. The outputs from each of the detecting steps are summed to obtain a total gamma radiation count for each segment from which the enrichment values for each segment as well as the average enrichment of said fuel rod may be calculated.

Abstract: A system for identifying a bar code label affixed to a rod wherein the bar code label including each bar thereof generally circumferentially spans on the rod an angle (the bar code angle) greater than 180.degree. and less than 360.degree. about the rod's longitudinal axis. The system includes a bar code reading optical scanner and a rod positioning mechanism. The scanner has a light beam from a single source and creates two scanning lines which superimposingly intersect at an angle which is greater than 360.degree. minus the bar code angle and which is less than or equal to 180.degree.. The rod positioning mechanism colinearly (or close enough to such) aligns the rod's longitudinal axis with the intersection line of the scanning lines so that the bar code label may be identified independent of the rotational position of the rod about its longitudinal axis.

Abstract: An individual nuclear fuel rod weighing system for rods carried on a tray which moves along a materials handling conveyor. At a first tray position on the conveyor, a lifting device raises the rods off the tray and places them on an overhead ramp. A loading mechanism conveys the rods singly from the overhead ramp onto an overhead scale for individual weighing. When the tray is at a second position on the conveyor, a transfer apparatus transports each weighed rod from the scale back onto the tray.

Abstract: A fuel rod puller in the form of a collet for pulling fuel rods from a storage area into grids of a nuclear reactor fuel assembly. The rod puller moves longitudinally through the grids to a storage area where projections on the end of leaf springs grasp onto an end plug in a fuel rod. Drive apparatus then pulls the rod puller and connected fuel rod from the storage area into the fuel assembly grids. The rod puller includes an outer tube having leaf springs on one end thereof in one modification, mounted within the outer tube is a movable plunger which acts to urge the leaf springs outwardly to a position to permit passing or with the end of a end plug. Upon withdrawal of the plunger, the leaf springs move into a groove formed in the end of a fuel rod end plug, and the fuel rod subsequently is pulled into the fuel assembly grids.