PCT53 is a highly visible and easy to understand pressure control process,
which uses pumped water to generate air pressure in a closed tank.
It comprises two clear acrylic vessels, an upper process vessel mounted
above an open sump tank. The process vessel is sealed and so the air
inside the tank is pressurised as water from the sump tank is pumped
into it. Water drains from the process tank back into the lower sump
tank via two outlets, one continuous and one incorporating a remotely
controlled solenoid valve. Both outlets incorporate interchangeable
orifices plus a hand operated variable valve, allowing the flow of water
to be varied continuously to suit particular demonstrations.