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:
Nov. 13, 1990
Filed:
Dec. 13, 1989
Applicant:
Inventor:
William W Dollison, Dallas, TX (US);
Assignee:
Otis Engineering Corporation, Dallas, TX (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
166133 ; 166188 ;
Abstract
A lock system for wells which includes a landing nipple in the well tubing and two embodiments of a lock mandrel, which are sealingly engageable and releasably lockable in the landing nipple to control flow through the well tubing. One lock mandrel is closed to flow and 'plugs' the landing nipple. The other lock mandrel, which will operate as a standing valve, has a through flow passage and a check valve preventing downward flow through the flow passage and lock mandrel. Both lock mandrels utilize 'C' rings for locking in landing nipples and may be released for expending downwardly from landing nipples by a predetermiend downward force.