Function
The Flow Head incorporates the following functions:
?● Gas indexed pneumatic inlet ports.
?● N2O gas flow cut off in the event of oxygen failure.
?● Flow control needle valves.
?● N2O/O2 flow ratio hypoxic mixture prevention proportioning system.
?● Flow tubes accurate to 10% of reading.
?● Color coded, market specific labels for flow tubes and flow tubes and flow control valves
?● Gas mixing chamber.
?● Mixed gas outlet.
?● O2 flush.
General Operation
?● The Flow Head integrates O2, N2O and Air channels (the N2O and Air channels are optional).
?● The O2 Air and N2O needle valves gas supply pressure is externally regulated to 200Kpa±10Kpa.
?● The N2O channel incorporates a pressure cut-off valve.
?● The O2 needle valve supply pressure in the circuit controls the output pressure of the pressure cut-off valve. Under all conditions of operation, the N2O flow shall reach zero before the O2 flow.
?● In this flow head the N2O pressure switch shall cut off the flow of N2O before the O2 pressure drops below 50+/-15Kpa. (adjust by customer)
?● Media: Medical grade O2, N2O and Air.
Performance
Note: Standard flow conditions defined at 20℃,101.3Kpa, (760mmHG)
Proportioning System
％Oxygen in Mixed Gas Total Flow
| Total Flow Below 1L/min | Total flow 1L/min and Above |
| Assemble | Min.22% | 22% to 28% |
| Field | Min.21% | 21% to 29% |
Assembly
Leakage from atmosphere shall not exceed 1SmL/min when a vacuum of 80cm H2O is applied to all internal passages of the flowhead assembly.
Operating and Storage Environment
Ambient Conditions:
| Operating | Storage |
| Temperature | 5 to 40℃ | -22 to 55℃ |
| Humidity | less than 80RH | less than 93RH |
| Pressure | 86 to 106kpa | 50 to 106kpa |
Materials
All wetted materials shall be compatible with all media gases and all anesthetic agents.