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. 12, 1995
Filed:
Aug. 26, 1994
Applicant:
Inventors:
Martin L Samuels, Houston, TX (US);
Bashir M Koleilat, Spring, TX (US);
David E Cain, Houston, TX (US);
John R Herold, Houston, TX (US);
Neil C Crawford, Spring, TX (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
166 851 ; 166 98 ; 166237 ; 294 8618 ; 294 8625 ;
Abstract
A wellhead retrieval tool assembly for retrieving a check valve has a spear formed as a solid ring at the bottom with free fingers extending upward. The fingers are resilient and have protrusions adapted to engage a retrieval groove in the check valve. A wedge ring is provided on the tool body to positively lock the fingers in radially outward engagement with the retrieval groove. The wedge ring is fixed to the body by a shear pin so that upon a predetermined axial force the pin shears and releases the wedge allowing withdrawal of the tool assembly.