<p>A casing assembly comprising: a first casing joint including a pin end and an outer surface adjacent the pin end; an external shoulder ring on the outer surface; and a casing coupling threaded onto the pin end and shouldered against the external torque shoulder ring. The external torque shoulder may be positioned before or after the coupling is installed on the pin end of the casing.</p>
申请公布号
WO2007093047(A1)
申请公布日期
2007.08.23
申请号
WO2007CA00218
申请日期
2007.02.14
申请人
ANGMAN, PER, G.;TESCO CORPORATION;TESSARI, ROBERT, M.