Abstract: A downhole tool for use in measurement-while-drilling applications includes modular ring connectors on opposed ends thereof with the ring connectors being interconnected by a single bus for delivering both power and ground.

Abstract: An apparatus for nuclear logging is presented. In accordance with the present invention, nuclear detectors and electronic components are all mounted in chambers within the sub wall with covers being removably attached to the chambers. A single bus for delivering both power and signals extends through the sub wall between either end of the tool. This bus terminates at a modular ring connector positioned on each tool end. This tool construction (including sub wall mounted sensors and electronics, single power and signal bus, and ring connectors) is also well suited for other formation evaluation tools used in measurement-while-drilling applications.

Abstract: An apparatus for nuclear logging is presented. In accordance with the present invention, nuclear detectors and electronic components are all mounted in chambers within the sub wall with covers being removably attached to the chambers. A single bus for delivering both power and signals extends through the sub wall between either end of the tool. This bus terminates at a modular ring connector positioned on each tool end. This tool construction (including sub wall mounted sensors and electronics, single power and signal bus, and ring connectors) is also well suited for other formation evaluation tools used in measurement-while-drilling applications.

Abstract: A method of thread timing for a rotary shouldered connection is presented. A ring gage which has a first and second scribe line thereon is used to establish a male timed rotary connection of a first tool. The angular distance between the first and second scribe lines is the advance timing correction (ATC), i.e., the angular distance between hand tight face-up and full torque make-up of a rotary connection comprising the male timed rotary connection of the first tool and a female timed rotary connection of a second tool. The second scribe line (indicative of the ATC) is transferred onto the first tool. A pin gage which has a third scribe line thereon is used to establish the female connection of the second tool. The third scribe line on the pin gage corresponds to the first scribe line on the ring gage. The third scribe line is transferred onto the second tool. When the first and second tools are rotatively connected at full torque, the transferred lines on the tools are in general angular alignment.

Abstract: A measurement-while-drilling (MWD) density tool is provided which incorporates a single gamma ray source and a pair of longitudinally displaced and mutually aligned detector assemblies (i.e., dual scintillation counters). A nuclear source is mounted in a pocket in the sub wall and partially surrounded by gamma ray shielding. The subwall section adjacent the source is expanded radially so as to define a lobe which displaces mud thus reducing borehole and mudcake effects. The two detector assemblies are mounted within a cavity or hatch formed in the subwall and enclosed by a detector hatch cover under ambient pressure. The detector assemblies are fixedly spaced from the source and are also partially surrounded by gamma ray shielding to provide good formation response. The hatch cover is secured to the sub by bolts and contains radiation transparent windows therethrough in alignment with the detector assemblies. A threaded-on fluid displacement sleeve is positioned on the sub and over the detector hatch cover.

Abstract: A method and apparatus for nuclear logging is presented. In accordance with the present invention, a radioactive source is mounted within the sub wall in alignment with the radiation detectors and orthogonal to the longitudinal axis of the sub. In addition, a novel radioactive source container and insertion tool is disclosed.