The Applied Physics Systems Model AP600 near bit sub measures inclination and gamma count data approximately two feet behind the bit. Data is wirelessly transmitted by the Model AP250 electric dipole transmission system around the downhole motor to the AP600. Received data is decoded by the AP600 electronics, where it is logged and periodically transmitted to the surface.
Read MoreInclination is sent continuously to the MWD system even while the drillstring is rotating and tracks very closely with the inclination measurement in the MWD system located above.
The azimuthal gamma sensor in the AP600 collects gamma counts while rotating and places this data into 1 of 8 bins. System software then tabulates the counts that correspond
to top and bottom bins and sends “up/down” or “high/low” information to the MWD System so that drilling decisions can be made in real time.
Versions
- 3.5 API Regular (for use with 4.75” to 5” mud motors)
- 4.5 API Regular (for use with 6.5” to 6.75” mud motors)
The 3.5 API Regular sub has four pockets, one each for inclinometer, gamma, transmission electronics, and battery.
The 4.5 API Regular sub has five pockets, with the same contents as the 3.5 API Regular sub, but with an extra battery. Battery life is typically between 80 to 120 hours per single battery stack.