Drilling system with electromagnetic transmission of information from the bottom, and insulating connector for this system

摘要

The transmission of the results of a measurement made at the bottom of a drill hole is performed by applying an a.c. electric signal between two metal areas 101, 111 of the drilling column. The insulation between these areas is made by an insulating connector which must transmit the mechanical forces used and which comprises for this purpose a screw 109 interacting with a nut 110. The thread 103 of the screw carries a ceramic coating which is permanently compressed on a support face by screwing to a high torque with abutment on a stop 105 provided for this purpose. The invention applies to all types of drilling. <IMAGE>