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Pre-outage activities

Procurement and design work for the cold source upgrade outage has already begun.  The NG-5, NG-6, and NG-7 neutron guides required to achieve confinement and restart the reactor have been ordered and are all scheduled to arrive by the end of 2021. New guide casings, casing supports, and shutters for these guides should arrive by the end of the first quarter of 2022.  The new guide system will then be pre-assembled in order to minimize the length of the outage as much as possible.

Because of the high radiation levels in the work environment, one of the biggest challenges is the removal of the existing cold source and the installation of the liquid D2 source. As part of our effort to reduce this exposure, we are building mock-up of the reactor, cold-source beam tube, and the cold beam penetrations allowing us to practice both the removal of the existing in-pile elements and cold source and the installation and alignment of the new components.  Through practice, we expect to become proficient with these tasks and identify improvements to our procedures thereby minimizing the radiation exposure to our staff.

In the last quarter of 2022, we will begin disassembly of NG-5, NG-6, and NG-7 in the Guide Hall. Disassembling these guides is necessary to make room for the removal of the components in D100. This work will close the instruments on these guides before the reactor outage begins.  However, this will shorten the outage, thereby reducing the downtime for all other instruments at the NCNR.

567 Pre-Shutdown Disassembly
Created April 8, 2020, Updated September 21, 2020