30-54 Overview
D20x22 Series II Navigator HDD
H
OW
A
UTO
D
RILL
W
ORKS
In all three modes, the AutoDrill program maintains the constant speed or pressure by limiting the thrust pump
output.
The AutoDrill program monitors both the rotation and thrust/pullback pressures for:
•
how rapidly the pressures are rising
•
the duration of the pressure increase
•
whether the pressures are continuing to increase over time
Initial Settings
When AutoDrill is enabled, the initial thrust and rotation pressures become reference set points, which are
allowed to change within limits.
When
Constant Speed
mode is selected, thrust speed is limited to the initial speed used when AutoDrill was
enabled.
In either constant pressure mode, AutoDrill maintains pressure by reducing thrust speed.
In
Constant Thrust Pressure
mode, the controller continually monitors the actual rotation pressure and
compares it to the reference rotation pressure.
In
Constant Rotation Pressure
mode, the controller continually monitors the actual thrust pressure and
compares this value to the reference thrust pressure.
