Length gauge for in situ measurement of water rod lengths in nuclear fuel bundles and methods of measurement

摘要

The length gauge includes an elongated standards rod, an indicator location block carrying a gauge and an indicator set block. The set block is applied to the location block and the gauge is zeroed out at a known distance between the movable element on the gauge and a reference surface. Water rods are assembled to a tie plate and the gauge is used to measure the length of the adjustable length water rods. The location block receives in a recess a portion of the tie bar of the water rod. The standards rod engages the tie plate and the gauge pin engages the opposite end of the standards rod. Any deviation in the length of the water rod from a designed length is indicated on the gauge.