seismic bracing of pipes

huangyhg

seismic bracing of pipes
the unistrut catalog specifies, "when supporting pressure piping, spacing of seismic bracing should not exceed two times the vertical support spacing.  stress in the pipes that are comparable to those required by asme b31.1 will be maintained."  i am providing seismic bracing above the roof for refrigerant piping in california.  do i need to provide seismic bracing at two times the vertical spacing?
from what one reads, and if you need to meet the specs in the catalog, yes. this resolves to any mandatory or contractual condition, as always. refrigerant piping will be understood pressure piping.
it all depends on the pipe diameter and support spacing. lateral bracing every other support is not out of the ordinary. there are some cases for large diameter pipes that the racks are say 30 feet appart, in that case the lateral bracing is provided at every support.
the key issue is whether the pipe can handle the lateral seismic loads applied and whether the lateral deformations are within acceptable limits.
if your vertical support spacing is very small and much less than the minimum required for the pipe, then you may be able to space the seismic braces further out.