Importance

Loading Importance Indicators...

Abstract

The device is operated with a conventional rotary drive with pile hammer. The torque and the ramming impacts of the drill head are transmitted to a drilling initial tube with drill bit. A sleeve without rotation stands inside the rotating initial tube. It rests at the bottom on the inside of the drill bit rotating below it. As a special feature, the sleeve is connected to the rotating drill head by means of a sleeve adapter with axially consecutive parts that can be rotated against each other and a PFR pressure, flushing and recovery tube connected to it. The PFR rotates with the drill head and the drill pipe, and the sleeve adapter communicates with the non-rotating sleeve. The PFR is used firstly to apply compressive force to the sleeve from above, secondly to flush it by guiding the flushing water for drilling in the PFR and forcing it out of the sleeve, and thirdly to allow the sleeve to be recovered for an almost undisturbed drilling test.

Loading the Abstract Image...

First Claim