Nozzle load calculation 1

OP,
Piping Codes directs designer to follow ASCE Code for seismic design. The ASCE Code provide guidance for designing piping systems that can withstand seismic forces. These codes specify requirements for seismic forces, support systems, and other design elements.
Seismic support systems, including hangers and bracings, are designed to withstand the forces generated by earthquakes. These systems are essential for maintaining structural integrity and preventing damage to the piping system.
You will find Vendors who design supports for seismic.
The Piping Code B31 which is based on Allowable Stress Design (ASD) will generally allow a higher SUS + OCC limit.
However, structural codes such as ASCE -7 is based on load resistance factor design (LRFD). ASCE 7 states that if ASCE loads used for ASD, the ASCE loads can be reduced by 30%, i.e., ASD=0.7(LRFD). But that is only for stress evaluation. Those ASCE loads should be used without reduction if you are after structural response of the piping system - pipe position and restraint load. This implies that there should be two analyses - one for stress - with the lower seismic load and a second analysis for system response - with the full load.

Kevin Chiu said:

Should seismic parameters be included in the calculation of nozzle loads?
Or are there separate standards or criteria specifically for assessing occasional loads such as seismic or wind?


Thanks

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Yes do allow for EQ, unless you are allowed to have the EQ rip the nozzles off the vessel.

Good advice from GDD on the design process.

Even plastic piping codes like ISO 14692 have allowance for occasional loads. You have not said what your vessel code is?