Graphite component structural integrity

Like the coolant channels, the neutron absorber channels are maintained by the structural integrity of the graphite elements and other components within the RS. (These channels are the control rod channels in the reflector columns adjacent to the active core and the reserve shutdown channels in the innermost ring of fuel columns.) Although some limited cracking of the graphite elements is possible (see discussion in Section 4.2.5.2.4.4),... 

Structural evaluation of core support and PSR blocks under horizontal dynamic SSE loads and impact conditions will be based on reactor vessel and CLR response. Adjustments to vessel and CLR response characteristics can be made, if required, to limit reactor graphite array loads and deflections to acceptable levels to assure safe control rod insertion and structural integrity of the internals components. 

Integral-type monolithic structures are produced by extrusion. The extrusion mixture generally includes the following components a type of carbon or carbon precursor such as activated carbon particles, graphite, carbon fibres, etc., a blinder such as phenol resin, hydroxylcellidose, coal tar pitch etc. and extrusion aids/plasticizers such as water or polymers. Typical preparation steps are mixing, extrusion, diying/solidification and carbonization. 

Todoroki, A., 2003. High performance estimations of delamination of graphite/epoxy laminates with electric resistance change method. Compos. Sci. Technol. 63 (13), 1911-1920. Weder, A., et al., 2012. A novel technology for the high-volume production of inteUigent composite structures with integrated piezoceramic sensors and electronic components. Sensors Actuators A 202, 106-110. 

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