DESCRIPTION
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Table Kelly equipment components description
Component
Description / Function
Drilling tool
Erodes and conveys soil.
Rotary drive
Generates rotary movement and torque for the
drilling tool and/or casing tube.
Its final gear is driven by planetary gears which
take power from hydraulic motors.
Casing drive adapter
Serves as a connector between the cardan joint
and the casing tube and transfers the torque.
Shock absorber
Absorbs shocks from the Kelly bar.
Cardan joint
Transfers torque from rotary drive to casing drive
adapter and prevents torsional stress.
Kelly driver
Transfers torque from rotary drive to Kelly bar.
Kelly bar (Kelly)
Consists of telescoping tubes the total length of
which determines the achievable depth of the bore.
It transfers torque from the rotary drive to the drill-
ing tool.