PRE-IRRADIATION SURVEY OF DIMENSIONS OF NS SAVANNAH CONTROL ROD, NUMBER 19

Control material for the N.S. Savannah reactor is stainless steel containing 1.7% boron enriched to 92% in the high neutron-absorbing isotope, boron 10. The reaction of a neutron with a boron 10 atom produces lithium and an alpha particle with an attendant volume increase. Irradiation effects data indicate that this volume change increases with increasing temperature and burnup of boron. The Savannah control rod design was influenced by the probability of a volume increase in the absorber material; however insufficient data are available to predict the magnitude of the volume change under operating conditions. A control rod placed in a high flux position in the core, and removed after a period of service, is remeasured to monitor actual volume changes. Behaviour predictions for the control rod can be made from this data as well as future improved control rod designs. A description of the methods used in measuring control rod 19 and subsequent recommendations are presented. (Author)

• Supplemental Notes:
  • This document is available for review at the Department of Commerce Library, Main Commerce Building, Washington, D.C., under reference number BAW-SUP-25-1.
• Corporate Authors:

  Babcock and Wilcox Company

  Development Department
  Lynchburg, VA  United States 
• Authors:
  • Johnson, C R
• Publication Date: 0

Media Info

• Features: Figures; Tables;
• Pagination: 17 p.

Subject/Index Terms

• TRT Terms: Control systems; Fuel elements; Nuclear powered ships; Nuclear reactors; Stainless steel
• Old TRIS Terms: Nuclear reactor control systems; Nuclear reactor fuel elements
• Subject Areas: Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00026303
• Record Type: Publication
• Source Agency: Maritime Administration
• Report/Paper Numbers: SUP-25-1
• Contract Numbers: AT(3-1)-2468
• Files: TRIS, USDOT
• Created Date: May 4 1973 12:00AM