TM 9-2320-269-10
LOCATION AND DESCRIPTION OF MAJOR COMPONENTS - CONTINUED
DERRICK - EXTERIOR - CONTINUED
Fiberglass Insulating Extension
Fiberglass insulating section is housed inside the outer derrick leg. This fiberglass section Is manually extended. The
fiberglass section Insulates the steel hydraulic extension against contact with high voltage power lines when crew
personnel are working in the aerial baskets.
Hydraulic Leg Extension
The hydraulic leg extension telescopes out and retracts hydraulically from the outer steel derrick leg tube. The hydraulic
leg extension is controlled from the operator's station and aerial basket.
Derrick Leg Elevation Cylinder
A hydraulic cylinder which elevates and lowers the derrick leg assembly. The elevating cylinder is controlled from the
operator's station and aerial basket.
TA 222502
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