The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 12, 2005
Filed:
Jul. 24, 2002
Richard Selinger, Edmonton, Alberta, CA;
Clifford J. Anderson, Edmonton, CA;
Brian R. Thicke, St. Albert, CA;
Michael F. Schoettler, Edmonton, CA;
Richard Selinger, Edmonton, Alberta, CA;
Clifford J. Anderson, Edmonton, CA;
Brian R. Thicke, St. Albert, CA;
Michael F. Schoettler, Edmonton, CA;
Other;
Abstract
A method and apparatus for causing pressure variations in a wellbore. A valve mechanism and a sealing device are provided in the wellbore. The valve mechanism is part of a valve device which may be actuated between an open position and a closed position. The valve device is actuated to the closed position to allow an increase in pressure below the sealing device and is actuated to the open position to allow a fluid to pass through the valve device up the wellbore. The valve device is alternately actuated between the closed position and the open position to cause cyclical pressure variations in the wellbore below the sealing device. The valve device includes the valve mechanism, a fluid passage, a control mechanism for controlling the valve mechanism, and a delay mechanism for delaying the actuation of the valve device from the open position to the closed position. The increase in pressure in the wellbore below the sealing device is caused by either or both of a fluid entering the wellbore from an adjacent formation or by the introduction of a pressurized fluid into the wellbore below the sealing device.