Document: NUREG-0800
Document ID: d2857477-655b-4e97-aa7c-3321de2d556e
Document Type: srp
Title: CONTROL ROD DRIVE SYSTEMS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0631/ML063190004.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.9.4
CFR Part: 
CFR Title: 

Content:
CRDS are reviewed to determine the acceptability of design margins for allowable values of stress, deformation, and fatigue used in the analyses. If an experimental testing program is used in lieu of analysis, the program is reviewed to determine whether it adequately covers stress, deformation, and fatigue. 3. A review of applicable design loads and their appropriate combinations, the corresponding design stress limits, and the corresponding allowable deformations is performed. The deformations are of interest in the present context only in those instances where a failure of movement due to excessive deformation could be postulated and such movement would be necessary for a safety-related function. If the applicant selects an experimental testing option in lieu of establishing a set of stress and deformation allowables, a detailed description of the testing program must be provided for review. The load combinations, design stress limits and allowable deformations criteria should be provided for review in the preliminary safety analysis report (PSAR). In the final safety analysis report (FSAR) for an operating license, or the final safety evaluation report (FSER) for design certification (DC) applications, the actual design should be compared with the design criteria and limits to demonstrate that the criteria and limits have not been exceeded. 3.9.4-3 Revision 3 - March 2007 Loadings imposed during normal plant operation and startup and shutdown transients include but are not limited to pressure, deadweight, temperature effects, and anticipated operational occurrences. Loadings associated with specific seismic and other dynamic events are then combined with the above plant-type loads. For boiling water reactors (BWRs) only, the CRDS is reviewed to verify that the system is capable of withstanding adverse dynamic loads such as water hammer. The response to each set of combined loads has a selected stress or deformation limit. The selection of a specific limit is