Coring in Slim Hole Wells
When drilling downsized conventional holes, conventional core barrels can be used. The addition of the anti-vibration technology (soft torque, thruster, Moineau motor, etc.) will improve penetration rates and reduce downhole failures in a similar manner to destructive drilling. More importantly, reducing vibrations should reduce core damage and core jamming.
Experience have shown the detrimental effects of core barrel vibrations on core quality and recovery factors, especially in weak, friable, unconsolidated sandstones.
The shortcomings of conventional coring are:
·The only force stopping the inner barrel rotating is the . . .