HYDROLOGICAL SERVICES PTY LTD
_______________________________________________________________________________________
The Hydrological Services bubble unit follows this layout closely, with the optional facilities
of bypassing the constant flow regulator valve and supplying the delivery pressure to river line
to expedite cleaning of line.
Dual Line Connections
For long line, the effect referred to in Fig.2 becomes significant and it is usual to make the
connection to the system near the orifice, so in effect there are two lines running the orifice.
Hence the term dual line.
The operation of Hydrological Services units is described in more details in diagrams 15 and
16 of “instruction Manual for Sherlock Pressure Sensing Units”.
Pressure Bulb or Closed System
The pressure bulb system relies on the normal
= constant relationship for gases under
PV
T
i
i
i
pressure.
Using similar diagrams to before, the closed system can be illustrated follows:-
Fig. 7- Atmosphere- up to the level at which the water seals off the bottom of the bulb.
Gas Purge Compressor
Issue 7:
16/12/03
© Copyright
HS55 110-019
