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, 2016
Filed:
Jul. 17, 2013
Applicant:
Weatherford Technology Holdings, Llc, Houston, TX (US);
Inventor:
Michael Boyd, Nisku, CA;
Assignee:
Weatherford Technology Holdings, LLC, Houston, TX (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B 21/08 (2006.01); E21B 21/06 (2006.01);
U.S. Cl.
CPC ...
E21B 21/08 (2013.01); E21B 21/063 (2013.01);
Abstract
An apparatus and method to control and exert a predetermined force back on the wellbore thereby controlling the hydrostatic force on the formation surrounding the well-bore, the inflow of fluids from the surrounding formation and the drilling circulating medium. The apparatus comprises and the method utilizes a pump having at least one pair of intermeshing and opposite-handed helical screws disposed within a chamber for restricting the flow of well bore returns. The speed of the pump may be varied to selectively restrict the flow of well bore returns from the well bore.