| 摘要 |
Abstract Core lifter 5 A method of forming a core lifter (126) for use in a drilling system (100), the core lifter (126) having a central axis, the method comprising: forming a tubular body of the core lifter (126) by stamping a sheet of material; and forming a plurality of longitudinally-oriented recesses in an exterior surface of the tubular body of the core lifter (126) by stamping the sheet of material, the plurality of longitudinally .0 oriented recesses extending radially inwardly relative to the central axis, wherein the core lifter has a length, and wherein the plurality of longitudinally-oriented recesses formed in the exterior surface of the tubular body of the core lifter (126) extend along at least 50 percent of the length of the core lifter (126). WO 2011/056809 PCT/US2010/055196 Tu i Fig. 2 |
