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US 7,451,819 B2Granted
Openhole perforating
AssigneeSchlumberger Technology Corporation
InventorsFrank F. Chang, Lawrence A. Behrmann, Ian C. Walton, Keng Seng Chan
Life of this patent
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Abstract
An underbalanced perforating system is disclosed for use in openhole completions to maximize the wellbore and matrix cleanup efficiency, to connect natural fracture patterns, and/or to enable application of new drilling fluid technology in difficult subsurface environments. The perforating system can be used for any hydrocarbon bearing formations with any lithology.
Claims8
An apparatus for use in an openhole well extending from a well surface, comprising:
- a closure member adapted to be positioned in the openhole well, the closure member defining a chamber therein, the chamber having a pressure lower than pressure in the wellbore at a selected wellbore interval;
- and
- at least one port selectively openable to establish communication between the chamber and the wellbore interval in the openhole well,
- wherein the at least one port when opened creating a fluid surge into the chamber to generate a transient underbalance pressure condition in the wellbore interval, the fluid surge to remove filtercake from the wellbore interval;
- wherein the closure member and at least one port are configured based on the transient underbalance pressure condition derived according to one of empirical data and modeling software for characteristics of an interval of the openhole well in which the transient underbalance pressure condition is to be created.
2 more elements
A method for use in an openhole well, comprising:
- ruining a surge tool in the openhole well to a target wellbore interval;
- activating the surge tool to generate a flow surge into the surge tool to create a transient underbalanced condition in the target wellbore interval;
- removing, by the How surge, filtercake from the target wellbore interval of the openhole well;
- and
- configuring the surge tool based on the transient underbalanced condition derived according to one of empirical data and modeling software for characteristics of the target wellbore interval in the openhole well in which the transient underbalanced condition is to be created.
2 more elements
Dependencies are inferred from the claim text.