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:
Aug. 29, 2000

Filed:

Aug. 20, 1997
Applicant:
Inventor:

Miles F Caraway, Shreveport, LA (US);

Assignee:

Other;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
166 843 ; 175195 ; 251-11 ; 277324 ;
Abstract

A rotating blowout preventor having a spring-steel reinforced stripper rubber removably mounted in a rotating inner housing, wherein the stripper rubber is sealed against the drill pipe by well bore pressure and externally-applied hydraulic pressure. In a preferred embodiment the externally-applied hydraulic pressure is maintained against the middle and upper portion of the stripper rubber by using a pump at a level of about ten percent above the well bore pressure to insure rotation of the stripper rubber with the drilling string and minimize rotation of the drill pipe inside the stripper rubber. A bayonet-type locking mechanism is attached to the stripper rubber for selectively removing the stripper rubber from the rotating inner housing and changing or repairing the stripper rubber.


Find Patent Forward Citations

Loading…