State the three purposes of the control rods.
The control rod blade assembly and associated drive mechanism (CRDM) serve three purposes:
1. Control of reactor power.
2. Shaping of both the axial and radial flux profiles to achieve optimum core performance and fuel utilization.
3. Insertion of adequate negative reactivity to shut down the reactor from any normal or abnormal operating condition.
State the purpose of the control rod blade.
3 types of blades in the core: