Abstract: A nuclear fuel channel has four corners and four elongated sidewalls disposed between the corners so as to provide a polygonal transverse cross-section. Each of the channel sidewalls has a longitudinal centerline that coincides with a line of maximum stress that is imposed on the sidewall during in-reactor service. The sidewalls have one or more longitudinal off-center lines that are located between the longitudinal centerline and one of the corners abutting the elongated sidewall. The longitudinal off-center line coincides with a line of minimum stress imposed on an elongated sidewall during in-reactor service. A weld is formed along the length of the off-center line on at least two of the sidewalls. At least one of the off-center line welds is also a seam weld. The disclosed arrangement provides improved resistance to bulging of the channel sidewalls during in-reactor service.

Abstract: An in-basin measuring system for determining changes in the longitudinal profile of nuclear fuel channel members which have been subjected to radiation in the reactor core section while maintaining the protective shield provided by the deep water in the storage basin of a boiling water nuclear reactor. A holder is provided having a support for a channel member with means for moving the channel member into a stepped gage coupled with means for indicating the position of the channel member in the gage to determine the dimensional changes along the length of the channel member.