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 The PackScan™ Gravel Pack Imager is a gamma-gamma density tool that measures changes in the bulk density of the gravel pack region. Washpipe conveyance reduces rig costs and speeds time to production.
The memory-based density logging tool identifies small voids in the gravel pack, and is unaffected by the presence of radioactive tracers used to evaluate proppant placement. Effects of borehole fluid variations and changes in tubular size and geometry are minimized.
Used as either a stand-alone pack evaluation tool or as a complementary technique in conjunction with ZeroWash® radioactive tracers, PackScan™ provides:
- Improved diagnostic sensitivity
- Quantifiable pack density calculations
- Accurate evaluation even with
tracers present
- Washpipe, slickline, electric line or
coiled tubing conveyance.
 The PackScan™ is designed for measuring the gravel pack quality. The principle of operation is that gamma rays leaving the source will be shielded by the annular gravel pack. Low pack quality or voids will allow more gamma rays to reach the detector. This is seen on the log as a higher count rate response. Also, to enable interpretation of this log it is necessary to superimpose an exact graphic of the well completion hardware. This completion graphic is exact in relative wall thickness and depth. The importance of the well diagram is to determine the difference between count rate increases and decreases that are caused by hardware from those that are caused by changes in the annular pack.
 Track 1 - Short Space Detector (SS)
The SS curve is presented in counts per second (CPS). Increasing CPS indicates a decrease in density and decreasing CPS indicates an increase in density. Changes in the hardware and Gravel Pack density affect the count rate. By reviewing the changes in count rate compared to the hardware diagram in Track - 2, these influences can be interpreted as being due to changes in the hardware or changes in the Gravel Pack density. Higher count rate response not associated with a hardware change identifies lower quality pack, voids, or top of pack.
Track 2 - Hardware and Interpreted Gravel Pack Quality
The depicted hardware is to exact scale based on the completion data provided by Service
Company (Depth, OD and ID dimensions). The hardware presentation in conjunction with the
SS and LS curves is used to make the interpretation of the Gravel Pack quality. The interpretation
is then graphically represented by the shading pattern in the annulus representing the gravel
packed intervals.
Track 3 - Long Space Detector (LS)
The LS curve is presented in counts per second (CPS). Increasing CPS indicates a decrease in
density and decreasing CPS indicates an increase in density. Changes in the hardware and
Gravel Pack density affect the count rate. By reviewing the changes in count rate compared to the
hardware diagram in Track - 2 these influences can be interpreted as being due to changes in the
hardware or changes in the Gravel Pack density. Higher count rate response not associated with
a hardware change identifies lower quality pack, voids, or top of pack.
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