Abstract: A downhole tool includes a mandrel and a deformable seal positioned around the mandrel to hold overpressure. An extrusion limiter is positioned around the mandrel, and adjacent to the deformable seal. The extrusion limiter includes a body, and grooves formed into the body that separate fins. The grooves have at least one portion formed at an acute angle relative to a circumferential line centered on the central axis of the extrusion limiter body. After the bending of the fins that occurs in use of the extrusion limiter, the gaps left by the grooves between the fins may be smaller than gaps left by straight grooves that are perpendicular to circumferential lines centered on the central axis of the body. The smaller gaps reduce extrusion of the deformable seal.

Abstract: A slip assembly for downhole tools comprises a slip ring for engaging a surface of a wellbore and a cone for expanding the slip ring into engagement with the surface of the wellbore. The slip ring has an interior surface defining a trough. The cone has an exterior surface defining a ridge. The trough is wider than the ridge, whereby the slip ring can bend over a top of the ridge.

Abstract: A slip assembly for downhole tools comprises a slip ring for engaging a surface of a wellbore and a cone for expanding the slip ring into engagement with the surface of the wellbore. The slip ring has an interior surface defining a trough. The cone has an exterior surface defining a ridge. The ridge is wider than the trough, whereby the slip ring can unbend over a top of the ridge.

Abstract: A downhole tool includes a mandrel and a deformable seal positioned around the mandrel to hold overpressure. An extrusion limiter is positioned around the mandrel, and adjacent to the deformable seal. The extrusion limiter includes a body, and grooves formed into the body that separate fins. The grooves have at least one portion formed at an acute angle relative to a circumferential line centered on the central axis of the extrusion limiter body. After the bending of the fins that occurs in use of the extrusion limiter, the gaps left by the grooves between the fins may be smaller than gaps left by straight grooves that are perpendicular to circumferential lines centered on the central axis of the body. The smaller gaps reduce extrusion of the deformable seal.

Abstract: A slip assembly for downhole tools comprises a slip ring for engaging a surface of a wellbore and a cone for expanding the slip ring into engagement with the surface of the wellbore. The slip ring has an interior surface defining a trough. The cone has an exterior surface defining a ridge. The trough is wider than the ridge, whereby the slip ring can bend over a top of the ridge.

Abstract: A slip assembly for downhole tools comprises a slip ring for engaging a surface of a wellbore and a cone for expanding the slip ring into engagement with the surface of the wellbore. The slip ring has an interior surface defining a trough. The cone has an exterior surface defining a ridge. The ridge is wider than the trough, whereby the slip ring can unbend over a top of the ridge.

Abstract: The invention relates to novel processes for the purification of radiolabelled tracers, using a solid-support bound scavenger group.

Abstract: This invention relates to the miniaturisation of radiosyntheses onto microfabricated devices, and in particular to use of microfabricated devices for radiosynthesis, isolation, and analysis of radiotracers for use in Positron Emission Tomography (PET).