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:
Jul. 17, 1984
Filed:
Nov. 24, 1982
Michael L Bowyer, Aberdeen, GB;
Baker Oil Tools, Inc., Orange, CA (US);
Abstract
An equalizing annulus valve for use in controlling flow in the annulus between two tubular conduits in a subterranean oil or gas well has a control pressure responsive main valve piston and a booster piston for closing radial flow ports. The booster piston is spring loaded relative to the main piston and excess annulus pressure below the valve acts on the booster piston rather than on the main piston. The main piston can be partially opened before abutting the booster piston to permit pressure below the valve to meter through an equalizing port in the main piston and through the main flow ports. When the pressure is equalized, the main piston and booster piston can be shifted to a fully open position. An auxiliary piston responsive to an increase in annulus pressure can also be used to shift the main piston.