Reverse-geometry pump pushes sand away
Schlumberger recommended the Left Helix PCP. The main cause of sand
plugging is accumulation of sand at the PCP intake. The Left Helix pump design
incorporates two changes to a conventional PCP design to reduce future plugging
risks. First, the conventional PCP bottom tag is replaced by a top tag, which
increases the area to flow at the intake. In addition, a second rotor is added
to the rotor string to pump a small fraction of the total rate downward
(reverse geometry) and prevent sand accumulation at the pump intake.
Both wells restored to economic production without sand problems
To verify the technology, Casabe Consortium installed Left Helix PCPs in
two pilot wells; installations proceeded normally and incurred no NPT.
In the first well, the Left Helix pump eliminated interventions and
deferred production related to sand flushing, enabling incremental production
valued at USD 50,000 at USD 50 per bbl. In addition, the improved sand
management enabled increased drawdown, improving oil production by 13%.
Finally, the new pump doubled the PCP run life from an average of 363 days to
732 days, further reducing interventions and production deferral.