Patent Number: 
Section: claims

1. An absorber rod for a nuclear reactor, comprising:a rod cladding defining an internal volume, the rod cladding having an upper end and a lower end;an upper end fitting positioned in the upper end of the rod cladding, the upper end fitting sealing the upper end of the rod cladding;a rod internal arrangement configured in the internal volume of the rod cladding, the rod internal arrangement made of a neutron absorbing material;an absorber rod lower end cap positioned at the lower end of the rod cladding, the lower end cap having an upper surface and a lower surface;a stack support made of a non-corrosive material and configured as a structural support, the stack support including a stack support upper end, a stack support lower end and an elongated stem connecting the stack support upper end to the stack support lower end, the stack support lower end placed in contact with the upper surface of the absorber rod lower end cap; andan annulus of material configured around the elongated stem and contacting the upper surface of the absorber rod lower end cap, the annulus of material made of a neutron absorbing material,wherein the stack support upper end supports the rod internal arrangement and separates the rod internal arrangement from the annulus of material, the load of the rod internal arrangement transferred through the elongated stem to the upper surface of the absorber rod lower end cap, the elongated stem extending through a center of the annulus of material. 2. The absorber rod according to claim 1, wherein the annulus of material is made of a silver-indium-cadmium alloy. 3. The absorber rod according to claim 1, wherein the cladding is configured in a tube shape. 4. The absorber rod according to claim 1, wherein an external surface of the rod cladding and an external surface of the lower end cap are flush where the rod cladding and lower end cap form a connection. 5. The absorber rod according to claim 1, wherein the stack support is configured to carry an entire weight of the rod internal arrangement and transport the entire weight to the lower end cap. 6. The absorber rod according to claim 1, wherein the stack support upper end is configured to have a larger outer perimeter than an outer perimeter of a stem of the stack support. 7. The absorber rod according to claim 1, wherein a diameter of the absorber rod is approximately 2.41 centimeters. 8. The stack support according to claim 1, wherein the stack support is made of a corrosion-resistant zirconium alloy.