Patent Number: 
Section: claims

1. A nuclear reactor support system comprising:an elongated reactor vessel having a weight and an internal cavity configured for containing a primary coolant, the reactor vessel extending along a substantially vertical axis;a reactor core disposed within the internal cavity;an upper portion of the reactor vessel located above a ground plane and a lower portion of the reactor vessel located below the ground plane;the upper portion of the reactor vessel comprising a primary coolant outlet port fluidly coupled to the cavity;a first flange fixedly attached to the upper portion of the reactor vessel and contacting the ground plane, the first flange supporting the reactor vessel; a second flange fixedly attached to the upper portion of the reactor vessel above the ground plane, the second flange spaced vertically apart from the first flange; anda plurality of welded lugs extending vertically between the first and second flanges. 2. The system according to claim 1, wherein the first flange supports the entire weight of the reactor vessel in a cantilevered manner. 3. The system according to claim 2, wherein the lower portion of the reactor vessel is disposed in a reactor well below the ground plane. 4. The system according to claim 3, wherein a bottom of the reactor vessel is spaced vertically above a floor of the reactor well. 5. The system according to claim 4, wherein the lower portion represents a majority of a length of the reactor vessel. 6. The system according to claim 1, wherein the upper portion of the reactor vessel further comprises a primary coolant inlet port located above the ground plane and fluidly coupled to the cavity. 7. The system according to claim 6, wherein the primary coolant inlet and outlet ports are fluidly coupled to a steam generator. 8. The system according to claim 1, wherein the ground plane is defined by a top surface of a concrete slab. 9. The system according to claim 8, wherein the concrete slab forms a portion of a reactor well which accepts the lower portion of the reactor vessel, the reactor well further comprising a plurality of sidewalls and a floor. 10. The system according to claim 9, wherein a bottom end of the reactor vessel is spaced apart from the floor of the reactor well such that the first flange supports the reactor vessel in a cantilevered manner. 11. The system according to claim 2, further comprising a domed head detachably coupled to the upper portion above the first flange. 12. The system according to claim 11, wherein the upper portion of the reactor vessel is terminated with a first bolting flange coupled to a mating second bolting of the domed head via a plurality of bolts.