초록

When adjacent pipes are made up by tool joints on outer tubes of dual conduit drill pipe, radially spaced pin and box on inner tubes shrink fitted in tool joints are sealed by bullet shaped seal rings around pin and in box compressed against shoulders and almost enclosed.

대표청구항 ▼

Dual flow passage drill stem member comprising: a tube having a flow passage therethrough, a pipe about said tube providing a flow passage between said pipe and tube, connector means at each end of said tube for making connection with correlative connector means on the tube of an adjacent drill stem

Dual flow passage drill stem member comprising: a tube having a flow passage therethrough, a pipe about said tube providing a flow passage between said pipe and tube, connector means at each end of said tube for making connection with correlative connector means on the tube of an adjacent drill stem member, joint means at each end of said pipe for making a rotary shouldered connection with correlative joint means on the pipe of an adjacent drill stem member, said connector means and said joint means at one end of said drill stem member being correlative to those at the other end of said drill stem member, said connector means at one end of said tube comprising a tubular pin having an annular external shoulder thereabout facing the extreme end of the pin and an external smooth cylindrical stabbing portion between said shoulder and said end of the pin and an external annular groove therearound adjacent the shoulder between the shoulder and the stabbing portion and a seal ring disposed in the groove having a protuberant portion lying against the shoulder, said connector means at the other end and said tube comprising a tubular box having an annular internal shoulder therewithin facing the mouth of the box and an internal smooth cylindrical stabbing portion between said shoulder and said mouth of the pin and an internal annular groove therearound adjacent the shoulder between the shoulder and the stabbing portion thereof and a seal ring disposed in the groove having a protuberant portion lying against the shoulder, the end of said pin and the mouth of said box of said tube connector means providing compressing surfaces which are positioned to compress protuberant portions of seal rings of correlative connector means of adjacent drill stem members when said joint means are made up with correlative joint means of adjacent drill stem members, and said protuberant portions of said seal rings being positioned to be compressed by the compressing suRfaces of the connector means of adjacent drill stem members with said joint drill stem members, thereby to form a double compression seal at each made up pair of connector means, the outer diameter of said stabbing portion of the connector means pin being smaller than the inner diameter of said stabbing portion of the connector means boxy by a distance of the order of at least 0.1 inch, whereby when said connector means are box up with correlative connector means on adjacent drill stem members there is formed an annulus between each pair of pin and box stabbing portions, closed off at the ends by the seal rings to prevent the entrance of detritus when the connector means are made up, and of sufficient size to receive without harm to the stabbing portion surfaces detritus paticles of the order of at least 0.050 inch maximum transversesection, and said stabbing portions do not fret under expected bending moments of said joint means, said joint means at one end of said pipe comprising a tubular pin having an annular shoulder thereabout and an externally tapered and threaded portion between the shoulder and the extreme end of the pin and an unthreaded portion between said shoulder and said threaded portion thereof, said joint means at the other end of said pipe comprising a tubular box adapted to receive such a joint pin and the mouth of the joint box providing a shoulder adapted to engage the shoulder on such a joint pin and having an internally tapered and threaded portion adapted to engage the threaded portion on such a joint pin and having an unthreaded portion between said mouth and the threaded portion of the box thereof, said shoulders on said joint pin and joint box limiting the axial makeup of said joint pin and joint box with correlative joint means on adjacent pipes, the connector means of each end of the tube being affixed to the joint means at the same end of the member to prevent relative axial motion therebetween so that the axial makeup of said connecotr means with correlative connector means on adjacent tubes is limited by said shoulders on the joint pin and joint box of said joint means on the pipe.