Top drive systems
Report 87.3.OS.2316, Transport Engineering and Logistics.
Several ways of letting the bit rotate do exist. This text emphasises the
difference between drilling with the use of a rotary table and the use of a
top drive (power swivel).
The idea of a top drive is not new, but lack of sufficient power made the
use of it impossible. Today's top drive systems can compete on an economical
basis with a rotary table, contrary to ideas that exist with some people.
Reports on Transport Engineering and Logistics (in Dutch)
, TU Delft