Abstract: A multi-conduit tubular having fluid conduits (30) and electrical conduits (108), with associated surface fluid (182) and electrical (186) commutators, and downhole sensors (18, 20, 290) for providing surface monitors (22) with instantaneous formation data. Each tubular (50) includes a plurality of uniform linear conduits (30) therethrough, with a gasketed seal plate (86) interposed between joined tubulars for assuring a high pressure seal between joined conduits. The seal plate (86) includes an intermediate electrical connector (126) for connecting electrical conduit connectors (116) of one tubular to another. A coupling collar (84) with uniform diameter internal coarse and fine threads (92, 94) joins the tubular ends having similar threads by differential thread action without respective tubular rotation.

Abstract: Apparatus for coupling multi-conduit drill pipes to maintain arcuate registry between connected pipes, and for transferring the drive torque of one drill pipe to the next drill pipe. One end of one drill pipe (50) includes drive lugs (100) matable with corresponding drive recesses (102) in the end of the next drill pipe (52). An index lug (104) in the drill pipe end, different that the drive lugs (100), is matable with a corresponding index recess (106) in another pipe end ot maintain arcuate registry of the coupled pipes and thus longitudinal alignment of the respective conduits (30) throughout the drill string. An internally threaded coupling collar (84) with different thread pitches at each end thereof is threadable onto the joined lug and recess mated drill pipe ends to hold the pipes mated. The joined pipe ends respectively include external threads (88, 90) of pitches corresponding to that of the coupling collar (84) so that a differential thread action draws the pipes together.