Document: NUREG-0800
Document ID: e4b3ba58-3c25-4846-b7b0-40b8e2866ecf
Document Type: srp
Title: CONTROL ROD DRIVE STRUCTURAL MATERIALS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340667.pdf
Revision Date: 2023-06
Chapter: 4
Section ID: 4.5.1
CFR Part: 
CFR Title: 

Content:
REVIEW RESPONSIBILITIES Primary - Materials Engineering Branch (NTEB) Secondary - None I. AREAS OF REVIEW General Design Criterion 26 requires that one of the reactivity control systems shall use control rods, preferably including a positive means for inserting the rods, and shall be capable of reliably controlling reactivity changes to assure that fuel design limits are not exceeded under conditions of normal operation, including anticipated operational occurrences. The areas listed below relating to materials considerations in the design of the control rod drive mechanism are reviewed. The review areas are similar to those given in Standard Review Plan Section 5.2.3, "Reactor Coolant Pressure Boundary Materials." For the purpose of this SRP section, the control rod system is comprised of the control rod drive mechanism (CRDM) and extends only to the coupling interface with the reactivity control (poison) elements in the reactor vessel; it does not include the electrical and hydraulic systems necessary for actuating the CRDOs. 1. Materials Specifications The properties of the materials used in the control rod drive are reviewed from the standpoint of adequate performance throughout the design life of the plant (or component). Materials commonly used include austentic stainless steels (which may be cold worked) chromium-plated stainless steels, martensi- tic stainless steels, precipitation-hardening stainless steels such as 17-4 PH, and other special-purpose materials such as cobalt-base alloys (Stellites), Inconel-750, Colmonoy-6, and Graphitar-14. 2. Austentic Stainless Steel Components Areas of review for austenitic stainless steel components are similar to the applicable subsections of SRP Section 5.2.3 covering fabrication and process- ing of austenitic stainless steels. Rev. 2 - July 1981 USNRC STANDARD REVIEW PLAN Standard review plans are prepared for the guidance of ihe Office of Nubesr Reactor Regulation staf responsible for the review of ppUco to construt