Core drilling appts for soft unconsolidated formations - using resilient tape with joinable edge for enclosing the core as formed

摘要

A core drilling appts. comprises a housing attached at the top to a splined expansion joint and at its lower end to a core bit, a core barrel suspended by bearings from the housing, and a resilient tape with one end outside the barrel and the other inside, the tape edges being joinable as the tape is drawn into the barrel to encase the core as it is formed. The sleeve is inexpensive and reusable, and it will not twist.