Leaders in Pipelin
e Survey Systems
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C
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A
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2
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SYSTEM MANUAL Version 6.03i
34
6.4.3. Locate Overhead
In order to take a reading the Detector needs to be directly over the pipeline – overhead.
Having located the pipeline as above, the surveyor will now move the Detector carefully
until the two black ‘overhead’ bars at the top of the SEARCH screen begin to close, as
shown below. The precise overhead position is achieved when they are as close together
as possible. A sample can now be taken.
Fig. 6.1
Locating the ‘overhead’ position
Fig. 6.2
Overhead bars closing
Fig. 6.3
Overhead bars meeting
6.4.4. Record Sample
i) Take Reading
Once the Detector has secured an overhead, two newly available function keys are
displayed: the
CALCULATION
and
CLOSE
keys.
CALCULATION
(
≈
►
=)
The
CALCULATION
key takes a large sample of readings and
converts these readings into accurate data. During this sampling
it is important that the Detector is held stationary and
perpendicular to the pipeline. Any movement will upset the
readings resulting in data errors.
CLOSE
(CLOSE)
The
CLOSE
key is for
CLOSE INTERVAL CURRENT SURVEY
mode. This is discussed in section 6.8.2
Keep the instrument still and press the
CALCULATION
key (
) now and the Detector
screen will temporarily change while the samples are being taken. Once the required
number of samples has been gathered the CALCULATE screen will be displayed.
Fig. 6.4
Preparing to take samples
Fig. 6.5
Taking samples
NOTE:
If the Detector is in DEMO mode, the display will loop through the process of
searching for the pipeline and obtaining an overhead signal. Press the
CALCULATION key when its symbol (
) appears.
