The Fairchild 30 is designed for applications that require high capacity and accurate process control in a small package. A poppet valve which is balanced by utilising a convoluted diaphragm, insures a constant output pressure even during wide supply pressure variations. Stability of regulated pressure is maintained under varying flow conditions through the use of an aspirator tube which adjusts the air supply in accordance with the flow velocity.
The Fairchild 30 Regulator uses the force balance principal to control the movement of the valve assembly which in turn controls the output pressure. When the regulator is adjusted for a specific set point, the downward force of the Positive Bias Spring causes the Diaphragm Assembly to move downward. The Supply Valve opens and allows air to pass to the Outlet Port. As the set point is reached, the downward force exerted by the Positive Bias spring is balanced by the upward force of the downstream pressure acting on the bottom of the Diaphragm Assembly. The resultant force moves the supply Valve upward to reduce the flow of air to the Outlet Port.
Outlet pressure is maintained as a result of balance between forces acting on the top and bottom of the Diaphragm Assembly.
250 psig, [17.0 BAR], (1700 kPa) Maximum
40 SCFM (68 m3/HR) @ 100 psig, [7.0 BAR], (700 kPa) supply and 20 psig, [1.5 BAR], (150 kPa) setpoint
Exhaust Capacity 2.0 SCFM (3.4 m3/HR) where downstream pressure is 5 psig, [.35 BAR], (35 kPa) above 20 psig, [1.5 BAR], (150 kPa) setpoint
Supply Pressure Effect
Less than 0.2 psig, [.014 BAR], (.14 kPa) for 100 psig, [7.0 BAR], (700 kPa) change in supply pressure
1/4" (.63cm) Water Column
-40°F to +200°F, (-40°C to 93.3°C)
Acceptable for use in Zones 1 and 2 for gas atmosphere:
Groups IIA and IIB and Zones 21 and 22 for dust atmospheres
Materials of Construction
Body and Housing: Aluminum
Diaphragms: Nitrile on Dacron