Document: NUREG-0800
Document ID: b3748a15-3b80-4626-a0a5-eb9f270739ad
Document Type: srp
Title: DETERMINATION OF RUPTURE LOCATIONS AND DYNAMIC EFFECTS ASSOCIATED
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340555.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.6.2
CFR Part: 
CFR Title: 

Content:
hould include: (1) A representative mathematical model. of the piping system or piping and restraint system. (2) The analytical method of solution selected. (3) Solutions for the most severe responses among the piping breaks analyzed. (4) Solutions with demonstrable accuracy or justifiable conservatism. The extent of mathematical modeling and analysis should be governed by the method of 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 ASME Class 1, 2, and 3 piping systems and other nonsafety class high energy piping systems include the following: (1) Lumped Parameter Analysis Model: Lumped mass points are inter- connected 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. (2) Energy Balance Analysis Model: Kinetic energy generated during the first guarter 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 uon impact on the restraint, an amplification factor of 1.1 should be used to establish the magnitude of the forcing function in order to deter- mine the maximum reaction force of the restraint beyond the