Document: NUREG-0800
Document ID: e9dbc75a-6786-40b3-b3a8-314219224fde
Document Type: srp
Title: -2
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1233/ML12334A360.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.9.3
CFR Part: 
CFR Title: 

Content:
e design of safety and relief valve systems with respect to the load combinations postulated for the safety or relief valves, upstream piping or header, downstream or vent piping, system supports, and BWR suppression pool discharge devices such as ramsheads and quenchers. The load combinations should include the most severe combination of the applicable loads due to internal fluid weight, momentum and pressure, dead weight of valves and piping, thermal load under heatup, steady state and transient valve operation, reaction forces when valves are discharging (thrust, bending, and torsion), seismic forces, and dynamic forces due to BWR safety relief valve discharge into the suppression pool as applicable. The reaction loads due to discharge of loop seal water slugs and subcooled or saturated liquid under transient or accident conditions shall also be included as valve discharge loads. The structural response of the piping and support system with particular attention to the dynamic or time-history analyses employed in evaluating the appropriate support and restraint stiffness effects under dynamic loadings when valves are discharging. If the use of hydraulic snubbers is proposed, the snubber performance characteristics are reviewed to ensure that their effects have been considered in the analyses under steady state valve operation and repetitive load applications caused by cyclic valve opening and closing during the course of a pressure transient. 3. Component Supports. The information submitted by the applicant includes an evaluation of Code Class 1, 2, and 3 components supports. An assessment of design and structural integrity of the supports. The review addresses three types of supports: plate and shell, linear, component standard types. All the component supports of these three types are covered in this SRP section. Although classified as component standard supports, snubbers require special consideration due to their unique function.