Document: NUREG-0800
Document ID: 2f470ae0-e3dd-42c9-9e54-b33682023619
Document Type: srp
Title: CONTROL ROD DRIVE STRUCTURAL MATERIALS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0702/ML070230007.pdf
Revision Date: 2023-06
Chapter: 4
Section ID: 4.5.1
CFR Part: 
CFR Title: 

Content:
REVIEW RESPONSIBILITIES Primary - Organization responsible for the review of control drive structural materials Secondary - Organization responsible for the review of materials engineering issues related to flaw evaluation and welding I. AREAS OF REVIEW General Design Criterion (GDC) 26 requires that one of the reactivity control systems use control rods, preferably with a positive means for inserting the rods, and be capable of reliably controlling reactivity changes for assurance that fuel design limits are not exceeded under conditions of normal operation, including anticipated operational occurrences. The review areas are similar to those of Standard Review Plan (SRP) Section 5.2.3, "Reactor Coolant Pressure Boundary Materials." For purposes 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 to actuate the CRDMs. The specific areas of review are as follows: 1. Materials Specifications. The properties of the control rod drive materials are reviewed for adequate performance throughout the design life of the plant (or component). Materials commonly used include austenitic stainless steels (which may be cold-worked), chromium-plated stainless steels, martensitic stainless steels, precipitation-hardening stainless steels like 17-4 PH, and such other special-purpose materials as cobalt-base alloys (Stellites), Inconel-750, Colmonoy-6, and Graphitar-14. 4.5.1-2 Revision 3 - March 2007 2. Austenitic Stainless Steel Components. Areas of review for austenitic stainless steel components are similar to the applicable subsections of SRP Section 5.2.3 for fabrication and processing of austenitic stainless steels. The use of sensitized stainless steels is reviewed and should be controlled to prevent stress-corrosion cracking of the material during plant