Thermal Generator Inert Gas Propellant (Models TDA-5A, 5B & 5C)

All ATI thermal condensation generators use approximately 20 standard cubic feet per hour of compressed inert gas during normal operation.  An inert gas is used since the heater block operating temperature is above the flashpoint of both DOP and PAO-4.

Nitrogen, either Oil Pumped (OP) or Water Pumped (WP), is generally readily available in size ‘B’ tanks or 60 cubic foot cylinders and therefore the most commonly used.  A ‘B’ tank allows approximately 3 hours of operation and a 60 cubic foot cylinder will allow approximately 4 hours of operation.  Another advantage of the size ‘B’ tank and the 60 cubic foot cylinder is that they are portable, weighing only about 30 pounds.

Other gases that are typically available are CO2, argon, neon, and helium. CO2 is available in smaller cylinders which lends to portability.

Two-stage regulators are required to maintain a constant output pressure as the internal bottle pressure continually drops during use.  A single stage regulator’s output varies extensively due to the starting bottle pressure of 2200 lbs. per square inch gauge.  It is imperative that the pressure supplied to the aerosol generator be adjusted and maintained at 50 psig due to internal pressure regulator adjustment for optimum performance.

If the aerosol output should become “wet”, use of the generator must be discontinued until the unit is repaired.

Nitrogen properties:
Molecular Weight: 28.01
Specific Volume: 13.8 CF/lb.
Flammable Limits: Nonflammable
CGA Valve: 580
DOT Name: Nitrogen, Compressed
UN #: UN1066
DOT Class: 2.2
DOT Label: Nonflammable Gas
CAS Registry: 7727-37-9
Inert Gas Consumption rate: ~20 CFH @ 50 PSIG generator inlet pressure.