Hello,

I have the following problem. I have to calculated a pipingsystem according to B31.3 which contains a static mixer. Does this mixer has any effect (except from the extra weight) on the caculation of the system and if so, what are the effects?
All help is appreciated.

Greetings,
W. Schmidt

The quick answer is maybe.

If your mixer is rather small, and rigid (compared to the piping system), then you could model it as a rigid element. It won't do anything significant to the system except for the addition of its weight.

If the mixer is rather large (and perhaps flexible) compared to the piping system, then you should model it as a pipe element. If necessary add weight to the nodes of the mixer using short rigid elements that don't connect to anything. With this alternative, the mixer shell may see some deflection and alter the loads on the connecting pipes.