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:
Mar. 06, 2001
Filed:
Jun. 21, 1999
Rudolf Antonius Henskens, Whitecairns, GB;
David Brands, Aberdeen, GB;
Western Atlas International, Inc., Houston, TX (US);
Abstract
An apparatus and method for removing sand and other debris from a wellbore. The apparatus is particularly suited for wireline operation, and requires minimal surface equipment. A housing is lowered into the wellbore until the housing is proximate to the sand, and a valve is opened to permit entry of the sand into a housing chamber. The housing can be raised to the wellbore surface so that the sand can be removed from the housing chamber. In one embodiment of the invention, the housing has two chambers each having a floating piston. A liquid is initially retained within the first chamber and is pressurized as the housing is lowered into the wellbore. Activation of a valve and differential pressures acting across the first piston move the liquid into the second chamber and draw the sand into the first chamber. The second chamber captures the liquid and facilitates return of the pistons to the initial position after the sand is emptied from the first chamber.