Page 102 - Open-Hole Log Analysis and Formation Evaluation

ton
the
gain
5.15)
FIGURE
caliper
Value
readings
example).
sensitivity
Calibrated
Offset
5.16
tool
tion—other
Well Services.
resistor
Uncalibrated
Computer
|
environment
Conventional
in
Calibrations
and
is
The
a
of measurement
than
/
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zero
to
Principle
;
(e.g.,
12-in.
systems
logging
(putting
of
Cal
Response
offset
place
computer
Uncalibrated
the
ring).
Yo
Point
7
adjusted when
Sf
the
raw data into calibrated data
systems
6-in.
eliminate
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the
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system
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Measured
tool
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the caliper tool
the
to
ring
(see fig.
The
require
sensor
Value
be’
Calibrated
is
accepts
over
=
need
— FIGURE 5.15 Conventional Calibration Method. resistor — offset —- Variable output Calibrated input ave gain resistor Variable EVALUATION DATA OF GATHERING FORMATION I. METHODS

7
Calibration.
at
5.16).
ina 6-in.
calibration
2

Slope
the
human
variable
is adjusted when the logging sensor is at the
for
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the
ring),
calibrated
.
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raw,
Calibrate
high
offset
Courtesy
in
Change
caliper
human
end
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For example,
Gain
the

of
arms,
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low end of its range
and the variable
uncalibrated
resistor (fig.
both
for
interven-
equation to transform
correct
the
a caliper
Schlumberger

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.
.

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and
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way
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crepancy
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337
337.cps;
calibration
shown
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calibrated
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example,
to
calibration
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companies
in
cps
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calibration was
calibrations?”
can
the
equation
fall
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(528-526),
and
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528
check
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from
be
tolerance
numbers
figure
For
calibration
use
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528
number
consider
generated
on
cps.
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again
these
the
a
5.18
PGS:
count
survey,
specified
the
cps,
performed
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include
logging
the
The
13.6
and for the
tolerated
near
rate
310,
computerized
different
fora
the
shows
these
values-refer
techniques
density
count
set
to
in
PDH:
will
count
calibrated
of
that
wellsite
tolerances
company
log
computer
gives
same
between
a
(NFDC)
categories:
be
respectively.
rates
tails
measured as
as
394,
on
numbers
rates,
sales
was
agreement
far count rates
shop
518
for
SFT:
were
listed
of
required gain. Thus,
is
specific
calibration
engineering
there
ring:
in
there
to
all
their
354.
Schlumberger
calibration,
records
count rates
jig
September
is’a
measured
526 cps, respectively. The question, therefore,
raw
personnel.
shown
tools.
logs.
three
figure
service
The
23,
cps and was
of density equipment
Using
as
was
measured
were
is:
calibrations
dis-
isalsoa