A Reactivity Control Device for Storing Nuclear Fuel

Primary Inventor: Krishna P. Singh
Contributing Inventor(s): Stephen J. Agace
Date of Filing: January 23, 2018
Status: Granted
Jurisdiction: US
Assignee: Holtec International, Inc.
Equipment Type: HI-SERT
Docket Number: HOL-099
Application Number: 15/137,842
Patent Number: US 9,875,819 B2

Prior Publication Data: US 2016/0314863 A1 (Oct. 27, 2016)

Related US Application Data: Provisional application No. 62/151,566, filed on April 23, 2015

PCT Filed: Apr 25, 2016
PCT No: PCT/US2016/029206
PCT Pub. No.: WO 2016/172705 A1

Abstract: A reactivity control device for storing nuclear fuel includes a top tube sheet, plurality of neutron absorber rods fixedly attached to the sheet, and a floating guide plate slideably mounted on the absorber rods for upward and downward movement between a lower position and an upper position. The reactivity control device is insertable into a spent fuel assembly in either wet storage in a spent fuel pool or dry storage in a canister. The absorber rods are inserted into empty guide tubes when the fuel assembly is removed from the nuclear fuel core normally occupied by control rods when in the reactor vessel. During installation, the device is lowered to insert the absorber rods into the guide tubes. The guide plate first engages the fuel assembly as the rods continue to slide through the plate until the tube sheet then engages the plate signaling the device is fully installed.