Document: NUREG-0800
Document ID: b6b57a00-5b85-4f0c-965c-ca89ef4265e7
Document Type: srp
Title: DETERMINATION OF RUPTURE LOCATIONS AND DYNAMIC EFFECTS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1608/ML16088A041.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.6.2
CFR Part: 
CFR Title: 

Content:
and restraint system. 3.6.2-9 Revision 3 – December 2016 ii. The dynamic analytical method selected. iii. Solutions for the most severe responses among the piping breaks analyzed. iv. Solutions with demonstrable accuracy or justifiable conservatism. The extent of mathematical modeling and analysis should be governed by the method of dynamic analysis selected. B. Dynamic Analysis Models for Piping Systems. Analysis should be conducted of the postulated ruptured pipe and pipe-whip restraint system response to the fluid dynamic force. Acceptable models for the analysis of American Society of Mechanical Engineers (ASME) Class 1, 2, and 3 piping systems and other nonsafety-class high-energy piping systems include the following: i. Lumped Parameter Analysis Model: Lumped mass points are interconnected by springs to take into account inertia and stiffness properties of the system and time histories of responses are computed by numerical integration, taking into account clearances at restraints and inelastic effects. In the calculation, the maximum possible initial clearance should be used to account for the most adverse dynamic effects of pipe-whip. ii. Energy Balance Analysis Model: Kinetic energy generated during the first quarter cycle movement of the rupture pipe and imparted to the piping and restraint system through impact is converted into equivalent strain energy. In the calculation, the maximum possible initial clearance at restraints should be used to account for the most adverse dynamic effects of pipe-whip. Deformations of the pipe and the restraint should be compatible with the level of absorbed energy. The energy absorbed by the pipe deformation may be deducted from the total energy imparted to the system. For applications where pipe rebound may occur upon impact on the restraint, an amplification factor of 1.1 should be used to establish the magnitude of the forcing function to determine the maximum reaction force of the restraint beyond the first quarter