Well bore liner hanger
Method of moving a through-the-flowline installed safety valve through a curved flow line
Subterranean well injection apparatus
Hydraulic tubing tensioner
Method and apparatus for multiple well completion
Completion apparatus and method for gas lift production
Method and system for maintaining and producing horizontal well bores
Dual hydraulic set packer
ApplicationNo. 989752 filed on 12/14/1992
US Classes:166/120, Anchor actuated by fluid pressure166/191, Spaced sealing portions166/212, Fluid pressure actuated166/217Expansible means translated by wedge or cam
ExaminersPrimary: Britts, Ramon S.
Assistant: Tsay, Frank
Attorney, Agent or Firm
International ClassesE21B 023/02
AbstractAn annular safety system for an oil well. The annular safety system is in the form of a hanger mechanism. The hanger mechanism is particularly effective in an oil well equipped for gas lift operation where gas is injected into an annular space between the well casing and the production tubing in order to aerate produced oil migrating up the wellbore through the production tubing. The hanger mechanism includes a casing nipple which is run into the well with the casing and a stationary threaded tubing holder which is run into the well with tubing. The hanger mechanism includes a device which, upon running the stationary threaded tubing holder into the well through the casing nipple, secures the stationary threaded tubing holder in a particular position relative to the casing nipple and prevents upward and downward movement of the stationary threaded tubing holder relative to the casing nipple. The hanger mechanism also includes a device allowing the hanger mechanism to selectively, independently seal each of the annular space between the well casing and the production tubing to prevent flow of injected gas and produced oil from the wellbore. Further, the hanger mechanism includes a release mechanism which may be selectively activated to allow the stationary threaded tubing holder and other downhole equipment to be upwardly retrieved from the well.