D7x11 Series II Navigator Directional Drill Operation 50-29
A compact Portable Breakout system is required whenever you loosen a joint away from the machine. Serious
injury or death can occur if drill rod rotation starts and you are struck by the wrench.
Refer to the Controls section, “Rod Joint Position Indicator,” page 20-18, for additional information on
positioning rod for breaking rod joints.
TRAILING ROD WHILE PRE-REAMING
Pre-reaming can be used in difficult drilling conditions when the desired bore diameter cannot be attained with
one pullback. One or more intermediate pre-reams can be made with increasingly larger reamers until reaching
the full diameter. Time can be saved by pulling in additional rod behind each pre-reaming pass. The next size
reamer can then be attached to the rod already in the bore. This process can be repeated as many times as
needed.
Swivel Use
Refer to “Swivel Use,” page 50-25, for information on swivel use when pre-reaming.