Abstract: A rotary coring device and a method for acquiring a sidewall core from an earth formation adjacent a wellbore are provided. The rotary coring device includes a coring tool having a housing with a core receptacle therein and being adapted for positioning at selected depths within the wellbore. The coring tool further includes a first gear assembly operably coupled to a rotary coring bit. The first gear assembly is configured to rotate the rotary coring bit. The rotary coring device further includes an electrical motor configured to drive the first gear assembly for rotating the rotary coring bit at one of a plurality of rotational speeds. The rotary coring device further includes a hydraulic actuator configured to move the rotary coring bit in a first direction toward the earth formation for obtaining the sidewall core and to move the rotary coring bit in a second direction away from the earth formation.

Abstract: A variable reluctance position sensor and a method for determining a position of a rotating body are provided. The variable reluctance position sensor includes a rotatable member configured to be operably coupled to the rotating body. The rotatable member has a first non-magnetic body portion and a plurality of magnets disposed equidistant from one another around an exterior region of the first non-magnetic body portion. The variable reluctance position sensor further includes a stator assembly having a second non-magnetic body portion with an aperture extending therethrough for receiving the rotatable member therein. The stator assembly further includes a plurality of coils and a plurality of coil brackets. Each coil of the plurality of coils is attached to a respective coil bracket of the plurality of coil brackets. The plurality of coil brackets are fixedly attached equidistant from one another to the second non-magnetic body portion.

Abstract: A variable reluctance position sensor and a method for determining a position of a rotating body are provided. The variable reluctance position sensor includes a rotatable member configured to be operably coupled to the rotating body. The rotatable member has a first non-magnetic body portion and a plurality of magnets disposed equidistant from one another around an exterior region of the first non-magnetic body portion. The variable reluctance position sensor further includes a stator assembly having a second non-magnetic body portion with an aperture extending therethrough for receiving the rotatable member therein. The stator assembly further includes a plurality of coils and a plurality of coil brackets. Each coil of the plurality of coils is attached to a respective coil bracket of the plurality of coil brackets. The plurality of coil brackets are fixedly attached equidistant from one another to the second non-magnetic body portion.

Abstract: A rotary coring device and a method for acquiring a sidewall core from an earth formation adjacent a wellbore are provided. The rotary coring device includes a coring tool having a housing with a core receptacle therein and being adapted for positioning at selected depths within the wellbore. The coring tool further includes a first gear assembly operably coupled to a rotary coring bit. The first gear assembly is configured to rotate the rotary coring bit. The rotary coring device further includes an electrical motor configured to drive the first gear assembly for rotating the rotary coring bit at one of a plurality of rotational speeds. The rotary coring device further includes a hydraulic actuator configured to move the rotary coring bit in a first direction toward the earth formation for obtaining the sidewall core and to move the rotary coring bit in a second direction away from the earth formation.