Control rod blade extension for a nordic nuclear reactor

Abstract

An apparatus or system that may incorporate a single component to connect the control rod blade to the control rod drive system (CRD) of a Nordic-type of BWR. The apparatus or system may eliminate the need of using multiple components to connect the control rod blade with the CRD.

1 . An apparatus for connecting a control rod blade (CRB) to a control rod drive (CRD) in a Nordic nuclear reactor pressure vessel (RPV), the CRB extending in an axial direction, the CRB including a neutron absorber section, the CRB shaped and sized to fit between a plurality of fuel bundles in the RPV, the CRD configured for linearly moving the CRB in the axial direction, the apparatus comprising:
 an adapter having a single-piece construction, wherein,
 the single-piece adapter includes a top axial end shaped to directly mate with a receptor in a bottom terminal edge of a single-piece lower fin configured to connect to the CRB directly below the neutron absorber section, 
 the single-piece adapter includes a bottom axial end with a fastener that removably connects directly to the CRD, 
 the single-piece adapter has an axial length spanning an entire distance between the receptor in the bottom terminal edge of the receptor and at least the top of the CRD, and 
 the single-piece adapter is configured to connect the single-piece lower fin and the CRD via only the single-piece adapter. 
   
     
     
         2 . The apparatus of  claim 1 , wherein the CRB includes the single-piece lower fin joined directly below the neutron absorber section, and wherein the single-piece adapter is configured to connect the CRM and CRD via only the single-piece adapter. 
     
     
         3 . The apparatus of  claim 1 , further comprising:
 the lower fin including the bottom terminal edge with the bottom terminal edge with the receptor to which the adapter is directly joined, wherein the lower fin is configured to join directly below the neutron absorber section of the CRB, and wherein the single-piece adapter is configured to connect the CRM and CRD via only the single-piece adapter and the lower fin.   
     
     
         4 . The apparatus of  claim 1 , wherein the CRB is cruciform and is configured to fit between the fuel bundles in to perpendicular transverse directions. 
     
     
         5 . The apparatus of  claim 1 , wherein the top axial end of the single-piece adapter is configured to be welded with the receptor in the bottom terminal edge of the lower fin, and wherein the adapter supports a weight of the CRB as the CRB is moved in a linear motion. 
     
     
         6 . The apparatus of  claim 5 , wherein the single-piece adapter is cylindrical. 
     
     
         7 . The apparatus of  claim 6 , wherein the axial length of the single-piece adapter is about 95 inches to about 105 inches. 
     
     
         8 . The apparatus of  claim 7 , wherein the single-piece adapter has an outside cylindrical diameter of about 2.5 inches to about 3.5 inches. 
     
     
         9 . The apparatus of  claim 9 , wherein the adapter is configured to affixed to an aft end of the CRB. 
     
     
         10 . A method of using the apparatus of  claim 3 , the method comprising:
 lowering the CRB through the fuel bundles so that the CRB is accessible below the fuel bundles;   connecting the single-piece adaptor to the CRB by mating the single-piece lower fin directly to the CRB; and   removably attaching the bottom axial end of the single-piece adaptor directly to the CRD.   
     
     
         11 . The method of  claim 10 , wherein the mating includes welding the top axial end of the single-piece adaptor directly to the receptor of the bottom terminal edge of the single-piece lower fin. 
     
     
         12 . The method of  claim 10 , wherein the removably attaching includes fastening the bottom axial end of the single-piece adaptor directly to the CRD. 
     
     
         13 . The method of  claim 10 , further comprising:
 driving the CRD to move the CRB in the axial direction.