We have three way valves up to 2-1/2 http://www.rosscontrols.com/PDFs/27Sol.pdfWe have also made a 3″ Lockout valve. It contains two parallel 2″ valves in one assembly with the ability to lock it out for OSHA 1910.147 requirements. I can email”
A cheaper method might be to use an actuated ball valve. 3 L ported ball valves are available with either electrical (slow… typically 12-20 secs) or with pneumatic actuation (reaction of around 1 sec) via either a double acting or single actin”