Sealed connector for deep drilling tools - where drilling liq. can be fed to tool, or another liq. can be fed into drilled hole without reaching the tool

摘要

A train of drill rods uses two concentric rows of tubes sepd. by an annular gap. On the bottom end of the tubes is a connector: and a drilling tool is located on the underside of the connector, e.g. by a screw thread. The connector is provided with ball bearings so it can rotate in an outer skirt while rotating the drilling tool. On the outside of the skirt are two sealing rings pressed against the wall of a drilled hole to prevent the passage of a drilling liq. between the skirt and the wall of the hole. Inside the connector are several channels, and at least one spring-loaded ball valve. When required, a pressurised fluid can be fed down the inner drill rod tube and into the drilled hole without reaching the drilling tool. Various liqs. can be fed into the drilled hole, e.g. for consolidating the earth forming the wall of the hole.PS.