APPARATUS FOR CARRYING OUT UNDERGROUND MEASUREMENTS DURING DRILLING OF UNDERGROUND STRATA

摘要

The invention concerns apparatus for performing underground measurements during drilling of underground strata using conventional measuring instruments. It comprises a closed instrument casing filled with oil, an adaptor coupling the casing to the drilling pipe, a spring holder connected to the instrument casing and carrying damping spring means, a helical plate controlling angular displacement and a piston-and-cylinder displacement control device, a first bore in the adaptor for conveying mud to a downward section of the drilling pipe, a second closable bore in the adaptor for permitting mud to flow from the annular space around the pipe through the instrument casing, and a closable bore in the instrument casing for communicating the pressure in the interior of the drilling pipe to the instrument casing.