Method and apparatus for removing mudcake from borehole walls
AssigneeSchlumberger Technology Corporation
InventorsFran.cedilla.ois M. Auzerais, Kenneth K. Liang
Life of this patent
Estimating the term…
Abstract
A portion of a borehole wall is isolated from surrounding borehole fluids by placing a chamber of a borehole tool against the borehole wall. The chamber comprises a cylindrical recess in an exterior surface of the borehole tool. The recess is open at one end to receive borehole fluids, and closed at the opposite end by a concave ultrasonic acoustic transducer. Mudcake present within the chamber and on the isolated portion of the borehole wall is disintegrated by the concave ultrasonic transducer. This approach can be used to remove mudcake from a borehole wall with a moving or stationary borehole tool.
Claims20
A method for treating an earth formation comprising:
- placing a tool in a borehole in a formation;
- isolating a portion of the formation by placing a chamber of the tool against a portion wall of the borehole, the chamber comprising a recess in an exterior surface of the tool;
- and
- producing acoustic energy as a spherically focused pulse within the chamber and loosening material from the borehole wall.
Method of treating an earth formation, the steps comprising:
- placing against a portion of a borehole wall of a formation, a partially spherical member recessed in an exterior surface of a borehole tool, the portion containing fluid and mudcake;
- and
- vibrating the partially spherical member such that the mudcake moves into fluid suspension at the isolated portion of the borehole wall.
Apparatus for treating an earth formation comprising:
- a borehole tool for positioning in a borehole in an earth formation, the borehole containing fluids and material and having a wall, the borehole tool being engageable with the borehole wall;
- at least one recess in the exterior surface of the borehole tool, the recess open to fluids contained in the borehole;
- an acoustic transducer positioned in each recess to contact the fluids contained in the borehole, the acoustic transducer arranged to produce a spherically focused acoustic pulse through the fluids and remove material from the borehole wall.
Apparatus for use in an earth formation, comprising:
- a body for passage within a borehole in a formation, the borehole containing fluid and having a wall;
- the body having a chamber for receiving and isolating some of the fluid;
- and
- an acoustic element substantially comprising the chamber for moving material in the chamber into suspension within the fluid.
Dependencies are inferred from the claim text.