Abstract: Three-position fluid valves for use in downhole environments are disclosed. An example valve includes first, second and third ports, a chamber coupled to the second port, a first sleeve to selectively couple the first port to the chamber and the second port, a second sleeve to selectively couple the third port to the chamber and the second port, and a piston that forms at least part of the chamber and is coupled to the sleeves. The piston moves between a first position in which the piston displaces the first sleeve to couple the first port to the chamber and the second port, a second position in which neither of the first or third ports is coupled to the second port, and a third position in which the piston displaces the second sleeve to couple the third port to the chamber and the second port.

Abstract: An apparatus includes a downhole tool for conveyance in a wellbore extending into a subterranean formation. The downhole tool includes a modular cartridge assembly that includes a chassis assembly within a housing and that includes a flow line and an electrical pathway. The modular cartridge assembly includes a first connector at a first end and a second connector at a second end. The first connector and the second connector are in fluid communication with the flow line and are further in electrical communication with the electrical pathway.

Abstract: The present disclosure relates to mandrel loading techniques for downhole tools. In One embodiment, a downhole tool field connection segment a chassis extending between field connection ends. The field connection segment includes first and second collars each including a chassis portion. A collar connector is coupled to each of the collars and compresses a first axial load device disposed in the first collar. A second axial load device is disposed in the second collar.

Abstract: Detecting a failure mode of a fluid flow controller configured to control fluid flow between first and second chambers of a downhole positive displacement pump and a flow line, wherein the positive displacement pump comprises a piston moving in an axial reciprocating motion, and subsequently adjusting operation of the downhole positive displacement pump based on the detected failure mode such that the downhole positive displacement pump piston operates differently in different axial directions.

Abstract: An apparatus including a downhole tool for conveyance in a wellbore extending into a subterranean formation and method of use thereof. The downhole tool may include a turbo-alternator disposed in a passageway for drilling mud, and a controller to: track operating points of the turbo-alternator, determine from the operating points a flow rate of the drilling mud, and control a component of the downhole tool based on the flow rate.

Abstract: Formation fluid sample container apparatus are described. An example apparatus includes a downhole tool having a body including an opening and a cavity extending into the body from the opening. The sample container includes an elongated container for holding a formation fluid sample and a sheath coupled to an outer surface of the elongated container and at least partially surrounding the elongated container. The sample container is fixed in the cavity and the sheath is to increase the mechanical integrity of the elongated container in a downhole environment.

Abstract: Three-position fluid valves for use in downhole environments are disclosed. An example valve includes first, second and third ports, a chamber coupled to the second port, a first sleeve to selectively couple the first port to the chamber and the second port, a second sleeve to selectively couple the third port to the chamber and the second port, and a piston that forms at least part of the chamber and is coupled to the sleeves. The piston moves between a first position in which the piston displaces the first sleeve to couple the first port to the chamber and the second port, a second position in which neither of the first or third ports is coupled to the second port, and a third position in which the piston displaces the second sleeve to couple the third port to the chamber and the second port.