Geotech Bladder Pumps, Installation And Operation Manual

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If planning to use an air compressor, use one with a reserve tank to insure proper air
supply to the pump. If using a Nitrogen Tank, see figure 5 for Nitrogen Tank Volume vs.
Bladder Pump consumption.
Determining PSI
Determine the air pressure needed to operate the Bladder Pump based on the length of
the air supply line to the pump (well depth).
Use the simplified formula:
0.5 PSI (per foot) + 10 PSI (to account for tubing friction) = required PSI
0.12 bar (per meter) + 0.7 bar (to account for tubing friction) = required bar
As mentioned above, the additional 10 PSI/ 0.7 bar is to account for the pump itself and
friction loss along the airline tubing. When the length of the airline is 50 ft./15 meters or
less, there is no need for the additional pressure.
To determine minimum operating pressures for the specific Bladder Pump model you are
using, consult the pump’s specifications. Typically, the minimum operating pressure will be
5 PSI/ 0.4 bar above static head.
Flowrates
Flowrates depend on pump size and pump depth. For example, a large pump at shallow
depths will produce the most flow, and a small pump at maximum depths will product the
least amount of flow. Speak with a Geotech representative to determine the best
configuration to meet sampling needs.
If using a nitrogen tank as an air source, see figure 5, Nitrogen Tank Volume vs. Bladder
Pump consumption.
For determining the number of cycles it will take to receive sample fluid at the well head,
see figure 6, Cycles vs. Depth.
The formulas stated above are not absolute, and are meant to
provide baseline information.