HIGH PRESSURE WIRELINE TOP-ENTRY PACKOFF APPARATUS AND METHOD

摘要

A high-pressure packoff (50) apparatus and method. The packoff (50) allows wireline (20) entering a top drive drilling head through a top entry access system (12) to be isolated to minimize the leakage and escape of drillstring fluids. An extension housing (122) containing a flow tube assembly (124) can be employed to effectuate a pressure drop along a wireline conduit (20).