<p>A double shoulder drill stem connection for high torque applications includes a thread taper within a range between about 1.0 and 1.2 inch per foot. The thread form is characterized by a stab angle between about 35 and 42 degrees and a load angle between about 25 and 34 degrees and by a short thread height with elliptical roots and with crests having an angle which slopes in an opposite direction with respect to the joint centerline from the thread taper. A drill string includes a tool joint having different inner diameters for a substantial axial length to provide enhanced strength in the threaded portion of the joint.</p>
申请公布号
WO2006092649(A1)
申请公布日期
2006.09.08
申请号
WO2005IB00587
申请日期
2005.03.02
申请人
SHAWCOR LTD.;WILLIAMSON, JOSEPH, STEPHEN
发明人
WILLIAMSON, JOSEPH, STEPHEN;GRANGER, SCOTT, L.;CHANCEY, ROGER, D.