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:
Dec. 27, 1994
Filed:
Oct. 14, 1992
Brown L Wilson, Tulsa, OK (US);
Oil Dynamics, Inc., Tulsa, OK (US);
Abstract
An electric submersible pumping system uses a small diameter capillary tube and a high pressure injection pump. The tube size is selected so that the frictional flow resistance of the tubing at the desired flow volumes balances the pressure caused by the height difference in the columns of fluid. The flexibility of the system is expanded by tapering the capillary tubing string, preferably, but not necessarily, using a larger inner diameter tube above and a smaller inner diameter tube below. Using calculated lengths of different diameter tubing, the pressure loss due to flow can be adjusted to suit the anticipated well conditions. For example, for a flow rate of two gallons per day of oil, a 4,000 foot well might start with 1,500 feet of 0.069' inner diameter tubing at the top and 2,500 feet of 0.055' inner diameter tubing on the bottom. The high pressure injection pump assures that the surface pressure will never go negative, even if the well productivity or other conditions are unknown or changing. Thus, there is a continual but limited flow of oil through the unit and into the well bore. The injection pump at the surface can be used in place of the electric submersible pump downhole oil reservoir. The oil that is supplied to the motor by the capillary tube system is injected directly into the motor head. Internal passages in the motor head introduce the fresh oil directly to the pothead or electrical connection cavity, which is the most failure prone area of the electrical system.