If you decide to use a purge option with your 80 GHz radar, here is what it looks like. The purge option is available on these antennas and process connections:
Lens, DN40 (1-1/2”) with 1-1/2” threaded connections
Lens, DN70 (2-3/4”) with 3” threaded connections
It comes with a G 1/4 threaded connection on the air hose connection.
What's interesting is that the purge connection merely becomes an extension of your existing process connection.
Remember that a radar sees through dust. But if you have an application where you think the build up will be so severe that it may cake and/or crust up very thick on the antenna, then a purge may be a good option and save some maintenance time.