Pressure Gauge

It would be unusual for a siphon to be used on a diaphragm-connected gauge. Siphons are usually to be found on steam service, where the combination of a condensate loop in the siphon and a snubber on the gauge do wonders in turning a pulsating steam pressure into a signal that can be read. It is extremely rare for a diaphragm gauge to be used on steam, therefore the likelihood of the combination appearing together would seem very remote.

I have seen a blankoff flange used with a siphon. The blankoff was tapped for the NPT used on the siphon. This connection was used on an air outlet from a Cat unit and measured pressure drop across the expander.