Method and apparatus for pressure coring with non-invading gel
AssigneeBaker Hughes Incorporated
InventorPierre E. Collee
Life of this patent
Estimating the term…
Abstract
A pressure core barrel including an inner tube containing a non-invasive gel for encapsulating a core sample. An anti-whirl core bit is employed, and the core bit and inner tube pilot shoe are configured and arranged to prevent damage to the core from drilling fluid. A special high viscosity, low spurt loss coring fluid is employed in the coring operation. When the encapsulated, pressurized care sample is brought to the surface, pressure is bled off and the core sample's chemical and mechanical integrity are substantially preserved by the gel.
Claims17
An apparatus for taking a core sample of rock from a subterranean formation, comprising:
- a pressure core barrel including:
- an outer barrel having a core bit secured to the lower end thereof adapted to cut said core sample for receipt by said core barrel;
- an inner tube assembly adapted to receive said core sample and maintain said core sample under pressure;
- and
- a non-invasive gel disposed in said inner tube assembly for encapsulating said core sample as it is received by said inner tube.
A method of taking a core sample of rock from a subterranean formation at the bottom of a borehole filled with drilling fluid, comprising:
- providing a pressure core barrel including an outer barrel having a core bit secured to the lower end thereof, and an inner tube assembly structured to receive a core sample cut by said core bit and to maintain said core sample under pressure;
- disposing a quantity of non-invasive gel in said inner tube assembly;
- running said core barrel to the bottom of said borehole at the end of a drill string;
- cutting said core sample by rotating said outer barrel with said drill string and engaging said formation with said core bit;
- receiving said core sample in said inner tube assembly as it is cut and encapsulating said core sample as it is received with said non-invasive gel;
- trapping said core sample under pressure in said inner tube assembly;
- and
- retrieving said core barrel with said pressurized, encapsulated core sample contained in said inner tube assembly.
Dependencies are inferred from the claim text.