Abstract: Nuclear logging tool. At least some of the illustrative embodiments are methods comprising placing a logging tool within a borehole proximate to an earth formation, releasing energetic neutrons from the logging tool, and receiving (at a detector within the logging tool) gamma returns indicative of interactions of the neutrons with elements of the logging tool and elements of the formation, and the gammas indicative of neutron interactions with elements of the logging tool are substantially free from gammas indicative of interactions with iron atoms.

Abstract: Nuclear logging tool. At least some of the illustrative embodiments are methods comprising placing a logging tool within a borehole proximate to an earth formation, releasing energetic neutrons from the logging tool, and receiving (at a detector within the logging tool) gamma returns indicative of interactions of the neutrons with elements of the logging tool and elements of the formation, and the gammas indicative of neutron interactions with elements of the logging tool are substantially free from gammas indicative of interactions with iron atoms.

Abstract: Various apparatus and systems, as well as methods and articles, may include the use of several compositions, such as solder formulations, including about 78%-83% by weight of lead, about 9%-11% by weight of antimony, about 1%-3% by weight of silver, and a balance of tin. Some embodiments include a process of removing a previously-existing lead finish, and applying a new finish to the lead to improve solder operation compatibility, as well as solder joint reliability in high temperature environments.

Abstract: A formation fluid sampling probe uses two hydraulic lines to recover formation fluids from two zones in a borehole. One of the zones is a guard zone and the other is a probe zone. The guard zone and the probe zone are isolated from each other by mechanical means, with the guard zone surrounding the probe zone and shielding it from the direct access to the borehole fluids. Operation of the tool involves withdrawal of fluid from both zones. Borehole fluids are preferentially drawn into the guard zone so that the probe zone recovers the formation fluid substantially free of borehole fluids. Separation of the guard zone from the probe zone may be accomplished by means of an elastomeric guard ring, by inflatable packers or by tubing. The device can be adapted for use either on a wireline or in an early evaluation system on a drillstring.

Abstract: This invention provides a formation evaluation tool for collecting a formation fluid in a chamber at a predetermined pressure and for maintaining the pressure of the collected fluid at a desired level during the retrieval of the chamber to the surface. The formation fluid is pumped into the chamber while a piston exposed to the hydrostatic pressure maintains the chamber pressure at the hydrostatic pressure. During retrieval of the chamber, the pressure in the chamber is maintained at a predetermined level by pumping wellbore fluid to the piston. A control unit at the surface is utilized for controlling the operation of the formation tool.

Abstract: A fluid flow velocity measuring device is shown. In the preferred and illustrated embodiment, an elongate body receives a removable spinner cartridge assembly. The assembly is formed of an elongate sleeve surrounding a rotating shaft supported by bearing assemblies at opposite ends of the shaft. The shaft supports a spinner. Particular sizes of spinners are calibrated to a particular flow velocity ranges and density of material. The insert is held in position by a compressed spring behind the insert so that fluid flow is directed from an inlet port in the tool adjacent a petal basket, along an axial passage in the tool, and through the spinner and out through an outlet port.