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.

Date of Patent:
Feb. 26, 1991

Filed:

Mar. 30, 1990
Applicant:
Inventors:

David Sask, Calgary, CA;

Marcel Obrejanu, Calgary, CA;

Allen Grimshaw, Calgary, CA;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ; E21B / ;
U.S. Cl.
CPC ...
166304 ; 166332 ;
Abstract

Dewaxing control apparatus is adapted for use in a well casing containing a production tubing string defining an annulus within the well casing and a down hole pump which pumps oil upwardly through the production tubing. The apparatus has a housing adapted to be installed in-line with the production tubing. A passage in the housing places the annulus in communication with the interior of the production tubing for purposes of circulating a hot dewaxing oil. A cup packer positioned below the passage closes the annulus against downward liquid flows. A gas by-pass passage in the housing permits gases to be exhausted upwardly through the annulus during oil production despite the presence of the packer. A valve mechanism responsive to pressure developed by pumping hot dewaxing oil down the annulus closes the gas by-pass passage and opens the liquid transfer passage so that the dewaxing oil can flow into the production tubing and back up to the surface. Flow of dewaxing oil into the oil-bearing formation is prevented.


Find Patent Forward Citations

Sask, David. (1991). Dewaxing control apparatus for oil well (U.S. Patent No. 4995462). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4995462

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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