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3. Design and basic technical data
Scubatech demand regulators are two-staged diving regulators with pressure
reduction stages separated by an interstage hose. They are composed of a first-
stage pressure reduction (pressure reducing valve), interstage hose and a second-
stage pressure reduction (diving regulator).
The first pressure reduction stages of demand regulators are pressure relief valves.
They are equipped with 2 or 4 reduced pressure ports marked with the letters LP and
1 or 2 high-pressure ports marked with the HP letters. The HP ports have larger
diameter than medium pressure ports. The first pressure reduction stages of
Scubatech demand regulators are also equipped with diaphragm, which protects
operating environment of the high-pressure valve and other valve components
against external conditions. This solution allows for using the valve in extreme
conditions and the regulator is also designed for use by advanced divers.
The main task of the first pressure reduction stages of demand regulators is to
reduce pressure in a diving cylinder (twinset) to the pressure value that corresponds
to the total pressure of ambient pressure (hydrostatic pressure variable depending on
depth) and constant overpressure of 0.9-0.95 MPa.
Figure 1.
The first stages of pressure reduction of demand regulators
The second pressure reduction stages of Scubatech demand regulators
are based
on a standard, concurrent relief pressure reducing system. They are equipped with a
Venturi nozzle with a setpoint adjusted by a diver that allows delivery of maximum
flow of breathing gases. Using an adjustable deflector that directs appropriately the
