Abstract: A system includes a valve subassembly configured to be disposed along an internal flowline exit of a first internal flowline within a downhole drilling module. The valve subassembly includes an active valve configured to regulate flow of a fluid through the internal flowline exit and a passive valve configured to be passively controlled based on a differential pressure between a first volume of the downhole drilling module and a second volume surrounding the downhole drilling module.

Abstract: A system includes a valve subassembly configured to be disposed along an internal flowline exit of a first internal flowline within a downhole drilling module. The valve subassembly includes an active valve configured to regulate flow of a fluid through the internal flowline exit and a passive valve configured to be passively controlled based on a differential pressure between a first volume of the downhole drilling module and a second volume surrounding the downhole drilling module.

Abstract: A system includes a valve subassembly configured to be disposed along an internal flowline exit of a first internal flowline within a downhole drilling module. The valve subassembly includes an active valve configured to regulate flow of a fluid through the internal flowline exit and a passive valve configured to be passively controlled based on a differential pressure between a first volume of the downhole drilling module and a second volume surrounding the downhole drilling module.

Abstract: A downhole tool for a wellbore within a geological formation may include a housing to be lowered into the wellbore, a probe carried by the housing having a first opening therein, and a packer carried by the probe. The packer may include a rigid base having a second opening therein aligned with the first opening, an inner elastomeric ring carried by the rigid base and having a third opening aligned with the second opening, a rigid intermediate containment ring carried by the rigid base and surrounding the inner elastomeric ring, and an outer elastomeric ring carried by the rigid base and surrounding the rigid intermediate containment ring.

Abstract: A downhole tool for a wellbore within a geological formation may include a housing to be lowered into the wellbore, a probe carried by the housing, and a packer carried by the probe. The packer may include a rigid base, an elastomeric member carried by the rigid base and having a recess therein, and a support member within the recess and comprising a plurality of rigid segments interconnected to allow relative movement between adjacent rigid segments. The rigid base, the elastomeric member, and the support member may each have respective aligned openings therein defining a fluid sampling inlet.

Abstract: An apparatus comprising a downhole tool having a body defining an outer surface, a plurality of standoffs distributed about the outer surface, and a hydraulic circuit operatively coupled to the standoffs. The hydraulic circuit includes a plurality of hydraulically actuated pistons, each of which is operatively coupled to a respective one of the standoffs to extend and retract the respective standoff. The pistons are hydraulically coupled and sized to extend or retract the respective standoffs at substantially the same rate in response to a hydraulic control signal.

Abstract: A downhole tool for a wellbore within a geological formation may include a housing to be lowered into the wellbore, a probe carried by the housing, and a packer carried by the probe. The packer may include a rigid base, an elastomeric member carried by the rigid base and having a recess therein, and a support member within the recess and comprising a plurality of rigid segments interconnected to allow relative movement between adjacent rigid segments. The rigid base, the elastomeric member, and the support member may each have respective aligned openings therein defining a fluid sampling inlet.

Abstract: A downhole tool for a wellbore within a geological formation may include a housing to be lowered into the wellbore, a probe carried by the housing having a first opening therein, and a packer carried by the probe. The packer may include a rigid base having a second opening therein aligned with the first opening, an inner elastomeric ring carried by the rigid base and having a third opening aligned with the second opening, a rigid intermediate containment ring carried by the rigid base and surrounding the inner elastomeric ring, and an outer elastomeric ring carried by the rigid base and surrounding the rigid intermediate containment ring.

Abstract: A system includes a valve subassembly configured to be disposed along an internal flowline exit of a first internal flowline within a downhole drilling module. The valve subassembly includes an active valve configured to regulate flow of a fluid through the internal flowline exit and a passive valve configured to be passively controlled based on a differential pressure between a first volume of the downhole drilling module and a second volume surrounding the downhole drilling module.

Abstract: Hydraulically actuated standoffs for downhole tools are described. An example apparatus includes a downhole tool having a body defining an outer surface and a plurality of standoffs distributed about the outer surface. The example apparatus also includes a hydraulic circuit operatively coupled to the standoffs. The hydraulic circuit includes a plurality of hydraulically actuated pistons, each of which is operatively coupled to a respective one of the standoffs to extend and retract the respective standoff. The pistons are hydraulically coupled and sized to extend or retract the respective standoffs at substantially the same rate in response to a hydraulic control signal.

Abstract: Conventional formation evaluation with dual inflatable packers includes the steps of pressurizing the packers so as to isolate an annular portion of the borehole wall, collecting one or more samples of formation fluid via the isolated portion of the borehole wall, and depressurizing the packers so as to permit movement of the mandrel within the borehole. A sampling method and apparatus that utilize one or more of the following to advantage is provided: restricting deformation of the packers during inflation using an annular bracing assembly; actively retracting the packers using ambient borehole pressure; and substantially centralizing the mandrel intermediate the packers so as to resist buckling of the mandrel.

Abstract: In one embodiment, an apparatus includes a base plate having a first aperture to receive an inlet in fluid communication with a downhole tool; a compliant outer cover having a first end terminating at the base plate and a second end terminating adjacent a forward opening of the inlet, the compliant outer cover having a first surface configured to engage a borehole wall and a second surface forming an inner cavity with the base plate; and a core disposed within the inner cavity and having a second aperture forming at least a portion of the inlet, wherein the outer cover comprises a first material and the core comprises a second material more compliant than the first material.

Abstract: Conventional formation evaluation with dual inflatable packers includes the steps of pressurizing the packers so as to isolate an annular portion of the borehole wall, collecting one or more samples of formation fluid via the isolated portion of the borehole wall, and depressurizing the packers so as to permit movement of the mandrel within the borehole. A sampling method and apparatus that utilize one or more of the following to advantage is provided: restricting deformation of the packers during inflation using an annular bracing assembly; actively retracting the packers using ambient borehole pressure; and substantially centralizing the mandrel intermediate the packers so as to resist buckling of the mandrel.

Abstract: Hydraulically actuated standoffs for downhole tools are described. An example apparatus includes a downhole tool having a body defining an outer surface and a plurality of standoffs distributed about the outer surface. The example apparatus also includes a hydraulic circuit operatively coupled to the standoffs. The hydraulic circuit includes a plurality of hydraulically actuated pistons, each of which is operatively coupled to a respective one of the standoffs to extend and retract the respective standoff. The pistons are hydraulically coupled and sized to extend or retract the respective standoffs at substantially the same rate in response to a hydraulic control signal.

Abstract: An apparatus comprising a downhole tool having a body defining an outer surface, a plurality of standoffs distributed about the outer surface, and a hydraulic circuit operatively coupled to the standoffs. The hydraulic circuit includes a plurality of hydraulically actuated pistons, each of which is operatively coupled to a respective one of the standoffs to extend and retract the respective standoff. The pistons are hydraulically coupled and sized to extend or retract the respective standoffs at substantially the same rate in response to a hydraulic control signal.

Abstract: Compliant packers for formation testers are disclosed. An example apparatus includes a base plate having a first aperture to receive an inlet in fluid communication with a downhole tool; a compliant outer cover having a first end terminating at the base plate and a second end terminating adjacent a forward opening of the inlet, the compliant outer cover having a first surface configured to engage a borehole wall and a second surface forming an inner cavity with the base plate; and a core disposed within the inner cavity and having a second aperture forming at least a portion of the inlet, wherein the outer cover comprises a first material and the core comprises a second material more compliant than the first material.

Abstract: Conventional formation evaluation with dual inflatable packers includes the steps of pressurizing the packers so as to isolate an annular portion of the borehole wall, collecting one or more samples of formation fluid via the isolated portion of the borehole wall, and depressurizing the packers so as to permit movement of the mandrel within the borehole. A sampling method and apparatus that utilize one or more of the following to advantage is provided: restricting deformation of the packers during inflation using an annular bracing assembly; actively retracting the packers using ambient borehole pressure; and substantially centralizing the mandrel intermediate the packers so as to resist buckling of the mandrel.

Abstract: Conventional formation evaluation with dual inflatable packers includes the steps of pressurizing the packers so as to isolate an annular portion of the borehole wall, collecting one or more samples of formation fluid via the isolated portion of the borehole wall, and depressurizing the packers so as to permit movement of the mandrel within the borehole. A sampling method and apparatus that utilize one or more of the following to advantage is provided: restricting deformation of the packers during inflation using an annular bracing assembly; actively retracting the packers using ambient borehole pressure; and substantially centralizing the mandrel intermediate the packers so as to resist buckling of the mandrel.

Abstract: A method for controlling fluid flow through a passageway includes slidably disposing a piston having a conduit that reduces the flow area through the passageway in the passageway and selectively closing the conduit of the piston by moving at least one of the piston and a plug.

Abstract: Conventional formation evaluation with dual inflatable packers includes the steps of pressurizing the packers so as to isolate an annular portion of the borehole wall, collecting one or more samples of formation fluid via the isolated portion of the borehole wall, and depressurizing the packers so as to permit movement of the mandrel within the borehole. A sampling method and apparatus that utilize one or more of the following to advantage is provided: restricting deformation of the packers during inflation using an annular bracing assembly; actively retracting the packers using ambient borehole pressure; and substantially centralizing the mandrel intermediate the packers so as to resist buckling of the mandrel.