Sage Acoustic Fluid Logger III, Справочное руководство

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Acoustic Fluid Logger and Pressure Pulse Gas Gun
23
Well Analysis
Identifying the fluid level kick
Remembering these few facts to make reading the fluid level tape easier.
• The fluid level is usually the deepest kick in the well.
• When shooting fluid levels with a positive pressure wave (as if is with compressed gas), the fluid
level always kicks
down on the tape.
• The fluid level is the only signal able to move over time, on a collar count basis. (If the acoustic
velocity of the gas in the well changes due to casing pressure changes, other signals in the well
can appear to move, but only as far as return time is considered.)
• Check the fluid level by allowing the printer to run long enough to print out the second reflection
of the fluid level at a distance equal to twice the original fluid level.
A double reflection from
the fluid level is an excellent confirmation of true fluid level.
What to do if more than one kick is observed
Many variables can affect the fluid level measurement on an oil or gas well, among them well depth,
the size of the compressed gas shot, debris in the wellbore, and external noise, to name only a few.
• Allow the casing pressure to build. And, the kick that moves on a collar basis will be the fluid
level.
• Shut down the pumping unit and give the well noise time to die down (i.e., one to five
minutes). Check for other sources of external noise. Then shoot the well again.
• Shut the casing flow line . When the casing flow line is left open, sound also reflects down the
flow line and this can interfere with the gas shot moving down the wellbore.
• Check the tubing tally for things like tubing anchor depth, liner depth, depth of special
oversized tools in the string, etc., for other objects that could show up as kicks on the fluid level
tape.
• If there is paraffin in this well, be aware that paraffin rings can cause false fluid levels in wells,
even in the face of increasing backpressure.
• Perforations in the well, or cracks in the casing, will kick up on the tape. Remember that the fluid
level will kick down .