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U.S. Department of Energy
Office of Scientific and Technical Information

Fluid sampling apparatus

Patent ·
OSTI ID:5287731

The patent describes an apparatus for extracting virgin fluid from a selected formation of a subterranean well isolated by a pair of vertically spaced packing units, comprising: an outer tubular housing sealably connectable between the packing units to lie adjacent to the selected formation; at least one radial port in the wall of the outer tubular housing communicating with the well annulus between the outer tubular housing and the selected formation; a hollow mandrel slidably mounted within the tubular outer housing and defining an isolated annular sampling chamber in the annulus between the hollow mandrel and the bore of the outer tubular housing. The bore of the hollow mandrel is communicable with a surface source of fluid pressure; a valve sleeve shiftable mounted within the annulus adjacent the radial port; first sealing means on the exterior of the valve sleeve preventing communication between the radial port and the sampling chamber in the run-in position of the apparatus; means responsive to a first fluid pressure in the hollow mandrel for axially shifting the valve sleeve from the run-in position to a first position to open communication between the radial port and the sampling chamber; thereby permitting flow of virgin fluid from the selected formation into the sampling chamber; second sealing means on the valve sleeve operative in a second axial position of the valve sleeve to block communication between the radial port and the sampling chamber; and means responsive to a second higher fluid pressure in the hollow mandrel bore for further shifting the valve sleeve to the second position.

Assignee:
Baker Oil Tools, Inc., Orange, CA
Patent Number(s):
US 4721157
OSTI ID:
5287731
Country of Publication:
United States
Language:
English