I know this isnt Mechanical Engineering but I dont know where else to post it. Basically we braze copper tubing in which the brazer use flux which fills the plant with white smoke(Boric Acid). We have hood that are connected to 2 Air Horns creating the ventilation.

The problem is my employer has a Main line coming off the 3" Airline Pipe. It goes from the pipe through a 1.5" hose into a 3/4" T fittings where it splits and goes to 2 seperate Air Regulators which eac h go to a seperate Air Horn. The Main Line Pressure is abou 120-135PSI.

The problem is these things are only getting 60-70PSI turn all the way up and they are not sucking out the Boric Acid properly.

I am guessing its because its split at the regulators. If Its split at where it comes off the main 3" pipe or if I beefed up the 3/4" to 1.5" where it splits can I get an increase of pressure?