Receiver apparatus for use in logging while drilling
AssigneeSchlumberger Technology Corporation
InventorsSergio Kostek, Thomas J. Plona, Shu-Kong Chang
Life of this patent
Estimating the term…
Abstract
An apparatus for reducing or eliminating the effects of a quadrupole component of an acoustic signal received from a transversely mounted acoustic source in a drill collar of a logging while drilling tool. The apparatus includes a drill collar for supporting a drill bit, a transversely mounted transmitter situated in a first horizontal plane in the drill collar which transmits acoustic energy into an earth formation. The drill collar also houses at least one receiver mounted in a second horizontal plane in the drill collar at an angular displacement from the transmitter such that the effects of a quadrupole component of the acoustic energy detected by the receiver are rendered insignificant.
Claims20
An apparatus for obtaining sonic logging while drilling a borehole traversing an earth formation, comprising:
- a drill collar for supporting a drill bit to drill the borehole, said drill collar having a central axis;
- a transmitter having a first end and a second end, transversely mounted in said drill collar a first horizontal plane perpendicular to said central axis for transmitting acoustic energy into the earth formation;
- and
- a first plurality of receivers mounted in said drill collar in second horizontal plane perpendicular to said central axis wherein said receivers are positioned substantially equal distances apart from each other about the exterior of said drill collar.
An apparatus for obtaining sonic logging while drilling a borehole traversing an earth formation, comprising:
- a drill collar for supporting a drill bit to drill the borehole, said drill collar having a central axis;
- a transmitter having a first end and a second end mounted transversely in said drill collar in a first horizontal plane perpendicular to said central axis for transmitting acoustic energy into the earth formation;
- and
- a receiver mounted in said drill collar at a second horizontal plane perpendicular to said central axis in said drill collar at an angular displacement from said transmitter such that the effects of a quadrupole component of said acoustic energy detected by said receiver are insignificant.
Dependencies are inferred from the claim text.