MANUAL – REFLEX EZ-TRAC™ | 64
10.5 Zeroing
An applicable reference value (zeroing) is needed to correctly
calculate the orientation of the wedge.
The zeroing value is automatically stored in
REFLEX™ EZ-COM at the
end of the Orientation survey. A stored zeroing may be used instead
of registering a new reference value, when starting up a survey.
Registering a new zeroing value eliminates the risk of using a
reference that is not applicable to the survey. Follow the instructions
in the section entitled Register new zeroing below.
If you are sure the stored zeroing value is applicable, continue to the
section Use stored zeroing below.
10.5.1 Register new zeroing
With the mule shoe sleeve attached to the wedge, you align the tool
face by setting the reference position to zero.
Note, the positioning of the instrument during the zeroing depends on
the survey mode; Gravity Tool Face or Magnetic Tool Face.
10.5.1.1 Position for zeroing – Gravity Tool Face
The gravity method shall be used for boreholes with inclinations from
-85 to +85 degrees. The instrument should be positioned as close to
horizontal as possible when the zeroing is performed.
If the wedge with the mule shoe sleeve is already in the borehole, the
zeroing measurement can be made with the mule shoe slot directed
vertically upwards. With this method however, the results will be
slightly less accurate.
Position for zeroing – Gravity Tool Face
1. Ensure that the mule shoe is clean and free from roughness.
2. Thread the bull plug onto the mule shoe.
3. Remove the bottom nose from the instrument.
4. Thread the bull plug, with the mule shoe attached, onto the
bottom of the instrument. Ensure that the locking nut located on
the bull plug is tight so the shaft does not rotate.
5. Slide the mule shoe into the mule shoe sleeve (see section Mule
shoe sleeve above).
6. Verify that the mule shoe rotates as necessary and that it slides in
correctly over the pin in the mule shoe sleeve.
7. Ensure that the kick direction of the wedge is still pointing
upwards and level.
8. Remove the top coupling of the
REFLEX EZ-TRAC™.
9. The instrument is now ready for the registration of the zero
position. Continue to the section Register zero position.
To Next Page
Loading...
Need help?
General
