Abstract: A selectively operable downhole valve for use with core sampling apparatus, the valve comprising a throughbore through which a first body may pass, and an obstructing member which is capable of selectively obturating the throughbore, the obstructing member being arranged to open or close the throughbore by movement of the first body with respect to the valve. A core sample of the formation may then be obtained and retrieved from the bore under pressure since the valve seals the bore downhole. Retrieving the sample under pressure maintains the integrity of the core sample so that subsequent analysis of the sample will more closely reflect the true characteristics of the formation.

Abstract: A selectively operable downhole valve for use with core sampling apparatus, the valve comprising a throughbore through which a first body may pass, and an obstructing member which is capable of selectively obturating the throughbore, the obstructing member being arranged to open or close the throughbore by movement of the first body with respect to the valve. A core sample of the formation may then be obtained and retrieved from the bore under pressure since the valve seals the bore downhole. Retrieving the sample under pressure maintains the integrity of the core sample so that subsequent analysis of the sample will more closely reflect the true characteristics of the formation.

Abstract: The present invention relates to an apparatus and method for recovering a sample from a subterranean formation. The apparatus comprises a receptacle for receiving a sample and at least two seal assemblies disposed on an inner surface of the receptacle. The seal assemblies can be arranged to allow a portion of the sample therethrough during the sampling process and to retain fluids within the receptacle during recovery of the sample. The seal assemblies can comprise at least one seal. The at least one seal can be provided with at least one fluid pocket configured to change shape as the volume of fluid therein alters in response to a pressure differential. A plurality of pairs of seal assemblies can be spaced along the length of the inner surface of the receptacle.

Abstract: The present invention relates to an apparatus and method for recovering a sample from a subterranean formation. The apparatus comprises a receptacle for receiving a sample and at least two seal assemblies disposed on an inner surface of the receptacle. The seal assemblies can be arranged to allow a portion of the sample therethrough during the sampling process and to retain fluids within the receptacle during recovery of the sample. The seal assemblies can comprise at least one seal. The at least one seal can be provided with at least one fluid pocket configured to change shape as the volume of fluid therein alters in response to a pressure differential. A plurality of pairs of seal assemblies can be spaced along the length of the inner surface of the receptacle.

Abstract: A method and apparatus for handling a geological sample, such as a core from a formation. The formation may be a formation of an oil and/or gas well. The apparatus includes a container for receiving the sample and is characterized in that the container comprises at least one wall with a surface which can change its configuration in response to pressure changes. The method of handling a geological sample obtained includes providing a container for receiving the sample. The container has a surface which is capable of changing its configuration in response to pressure changes. The sample is introduced into the container, and the configuration of the surface is changed to contact the sample. The container is then withdrawn from the formation.

Abstract: Core machine intended particularly to the oil prospection field, comprising a core crown (2), an external tube (3) for the rotational driving of the core crown (2), and an internal tube (4) having a free front end element (7) intended to receive a core (5), and a revolution surface (8) of the free end element (7) on the crown side (2), arranged to cooperate with an internal surface (9) thereof, or optionally of the external tube (3), so as to adjust between the two a predetermined passage for the core drilling fluid, the free end element (7) being mounted in the core drilling machine (1) so as to slide coaxially on an extremity section (13) of the internal tube (4), between a position wherein the revolution surface (8) is in contact with the internal surface (9) of the crown (2), or respectively of the external tube (3), and an extreme position away from said internal surface (9).