Learn about ANSTO's core activities; the OPAL research reactor, its science, safety culture, board and organisational structure, news visitors information and events.
OPAL Operating Cycles
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| View of OPAL's reflector vessel |
The OPAL research reactor operates on an annual (calendar year) program. This page provides details of OPAL's operating cycles, including maintenance information and a link to the neutron-scattering instruments' user schedule.
Typical operating cycles
OPAL typically operates in cycles of 30-35 days, followed by a short refuelling outage to remove two or three spent fuel assemblies and replace them with new fuel assemblies.
During these types of outages, ANSTO's Reactor Operations team perform predictive, preventive and corrective maintenance. These refuelling outages currently last around four to six days, although the intention is to reduce this in future.
The Reactor Operations team aims to operate OPAL for 300 days each calendar year.
Extended maintenance
In addition, there are longer maintenance outages that enable more extensive inspections, refurbishment and maintenance work to be carried out. These maintenance outages vary in length, depending on the work required, but are generally between one and four weeks in length. They would normally also include refuelling the reactor.
Scientific users
For users of Opal's neutron-scattering instruments, a day of beam time runs for 24 hours; for example from 9 am to 9 am the following day. The current beam users' schedule can be found on the Bragg Institute's online customer portal.
Reactor schedule - 2012/2013*
| CYCLE NUMBER | FROM | TO |
| 45 | 7/10/2012 | 4/11/2012 |
| 46 | 17/12/2012 | 20/1/2013 |
| 47 | 26/1/2013 | 24/2/2013 |
| 48 | 2/3/2013 | 1/4/2013 |
| 49 | 7/4/2013 | 12/5/2013 |
| 50 | 18/5/2013 | 16/6/2013 |
| 51 | 30/6/2013 | 4/8/2013 |
| 52 | 10/8/2013 | 8/9/2013 |
| 53 | 14/9/2013 | 13/10/2013 |
| 54 | 19/10/2013 | 23/11/2013 |
| 55 | 6/12/2013 | 5/1/2014 |
| 56 | 11/1/2014 | 16/2/2014 |
| 57 | 22/2/2014 | 23/3/2014 |
| 58 | 29/3/2014 | 27/4/2014 |
| 59 | 3/5/2014 | 6/6/2014 |
*This schedule is based on a fixed fuel management strategy and is subject to revision.
Page last updated 31.07.13. Revision no: 19.

