Abstract
The beryllium (Be) reflector elements of the SAFARI-1 Research Reactor were replaced in October 2011 as part of the Ageing Management Programme of the reactor. After more than three million MWh of operation over a period of 47 years, core reloading became more difficult due to the geometric deformation of the beryllium reflector elements. During the replacement of the reflector elements, criticality and reactivity worth experiments were performed and found to compare favorably with calculated values. A Beryllium Management Programme was established at SAFARI-1 to identify and apply effective and appropriate actions and practices for managing the ageing of the new beryllium reflector elements. This will provide timely detection and mitigation of ageing mechanisms relevant to beryllium reflector elements, supporting the life extension of these elements. These actions and practices include monitoring of the tritium levels in the primary water, calculating and measuring the fluxes within the beryllium reflector positions, measuring the straightness of the elements to track geometric deformation and visually inspecting the reflector elements for crack formation. Acceptance criteria indicating the end of life of the elements were established. These criteria take into account the smallest gap that could exist between elements, sudden changes in the tritium levels
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Kock, Marisa De;
Vlok, Jwh;
Steynberg, B J
[1]
- South Africa Atomic Energy Corporation (Necsa) (South Africa)
Citation Formats
Kock, Marisa De, Vlok, Jwh, and Steynberg, B J.
SAFARI-1 research reactor beryllium reflector element replacement, management and relocation.
Japan: N. p.,
2012.
Web.
Kock, Marisa De, Vlok, Jwh, & Steynberg, B J.
SAFARI-1 research reactor beryllium reflector element replacement, management and relocation.
Japan.
Kock, Marisa De, Vlok, Jwh, and Steynberg, B J.
2012.
"SAFARI-1 research reactor beryllium reflector element replacement, management and relocation."
Japan.
@misc{etde_22078597,
title = {SAFARI-1 research reactor beryllium reflector element replacement, management and relocation}
author = {Kock, Marisa De, Vlok, Jwh, and Steynberg, B J}
abstractNote = {The beryllium (Be) reflector elements of the SAFARI-1 Research Reactor were replaced in October 2011 as part of the Ageing Management Programme of the reactor. After more than three million MWh of operation over a period of 47 years, core reloading became more difficult due to the geometric deformation of the beryllium reflector elements. During the replacement of the reflector elements, criticality and reactivity worth experiments were performed and found to compare favorably with calculated values. A Beryllium Management Programme was established at SAFARI-1 to identify and apply effective and appropriate actions and practices for managing the ageing of the new beryllium reflector elements. This will provide timely detection and mitigation of ageing mechanisms relevant to beryllium reflector elements, supporting the life extension of these elements. These actions and practices include monitoring of the tritium levels in the primary water, calculating and measuring the fluxes within the beryllium reflector positions, measuring the straightness of the elements to track geometric deformation and visually inspecting the reflector elements for crack formation. Acceptance criteria indicating the end of life of the elements were established. These criteria take into account the smallest gap that could exist between elements, sudden changes in the tritium levels and formation of cracks. All the data obtained through the Beryllium Management Programme are recorded in a database. Additional benefits gained through a Beryllium Management Programme are the availability of a complete irradiation history of the beryllium reflector elements at any point in time and the establishment of a knowledge base to assists in the understanding of the behavior of the beryllium reflector elements in an irradiation environment. Straightness baseline measurements of the new beryllium reflector elements were performed with a beryllium straightness measurement tool, designed at SAFARI-1. The decommissioned beryllium elements were also measured to investigate the occurrence of ageing mechanisms and their consequences, and to determine the location of the element's vulnerable areas. This supports the Beryllium Management Programme in terms of an optimal shuffling scheme to mitigate the effects of ageing. Currently, the decommissioned beryllium reflector elements are stored in a storage rack within the reactor pool. Due to limited space it is necessary to relocate these elements. A proposed relocation strategy based on existing literature is discussed. This strategy covers the requirements, relocation process and types of storage to be considered. (author)}
place = {Japan}
year = {2012}
month = {Mar}
}
title = {SAFARI-1 research reactor beryllium reflector element replacement, management and relocation}
author = {Kock, Marisa De, Vlok, Jwh, and Steynberg, B J}
abstractNote = {The beryllium (Be) reflector elements of the SAFARI-1 Research Reactor were replaced in October 2011 as part of the Ageing Management Programme of the reactor. After more than three million MWh of operation over a period of 47 years, core reloading became more difficult due to the geometric deformation of the beryllium reflector elements. During the replacement of the reflector elements, criticality and reactivity worth experiments were performed and found to compare favorably with calculated values. A Beryllium Management Programme was established at SAFARI-1 to identify and apply effective and appropriate actions and practices for managing the ageing of the new beryllium reflector elements. This will provide timely detection and mitigation of ageing mechanisms relevant to beryllium reflector elements, supporting the life extension of these elements. These actions and practices include monitoring of the tritium levels in the primary water, calculating and measuring the fluxes within the beryllium reflector positions, measuring the straightness of the elements to track geometric deformation and visually inspecting the reflector elements for crack formation. Acceptance criteria indicating the end of life of the elements were established. These criteria take into account the smallest gap that could exist between elements, sudden changes in the tritium levels and formation of cracks. All the data obtained through the Beryllium Management Programme are recorded in a database. Additional benefits gained through a Beryllium Management Programme are the availability of a complete irradiation history of the beryllium reflector elements at any point in time and the establishment of a knowledge base to assists in the understanding of the behavior of the beryllium reflector elements in an irradiation environment. Straightness baseline measurements of the new beryllium reflector elements were performed with a beryllium straightness measurement tool, designed at SAFARI-1. The decommissioned beryllium elements were also measured to investigate the occurrence of ageing mechanisms and their consequences, and to determine the location of the element's vulnerable areas. This supports the Beryllium Management Programme in terms of an optimal shuffling scheme to mitigate the effects of ageing. Currently, the decommissioned beryllium reflector elements are stored in a storage rack within the reactor pool. Due to limited space it is necessary to relocate these elements. A proposed relocation strategy based on existing literature is discussed. This strategy covers the requirements, relocation process and types of storage to be considered. (author)}
place = {Japan}
year = {2012}
month = {Mar}
}