Method and apparatus for annulus pressure responsive circulation and tester valve manipulation
AssigneeHalliburton Company
InventorsRobert L. Jessup, Joe E. Coleman
Life of this patent
Estimating the term…
Abstract
A releasably locked closed circulation valve is introduced into a well bore as part of a drill string. The annulus between the drill string and the well bore, or casing affixed to the well bore, is sealed. Pressure is applied to the annulus and the valve unlocks and opens once the annulus pressure reaches a certain level to allow circulation between the annulus and the interior of the drill string. An optional locking device preferably locks the opened valve in the open position. A second embodiment includes a tester valve simultaneously operable with the circulation valve.
Claims7
In a pipe string located in a fluid filled well bore so as to vertically separate said well bore into an annulus region and an axial bore region, said pipe string including a circulation valve, the method of movement of said circulating valve from a first position preventing to a second position allowing fluid communication between said regions, comprising the steps of:
- isolating a negligible pressure gas chamber within said pipe string from said axial bore and said annulus region;
- pressurizing one of said regions to a pressure of at least a predetermined magnitude above the pressure in said isolated chamber;
- unlocking said circulating valve when the pressure in said pressurized region reaches said predetermined magnitude;
- moving said unlocked circulating valve from said first position to said second position in response to the pressure in said pressurized region;
- and
- maintaining said moved valve in said second position.
Apparatus for circulation of well fluids in response to pressure in an isolated portion of an annulus between a pipe string and a surrounding well bore, comprising:
- a. a hollow cylindrical housing having a recess communicating with the isolated portion of the annulus, an axial interior bore, a passageway communicating the axial interior bore with the annulus, and means for connecting the housing in said pipe string;
- b. a valve body carried by said housing and at least partially overlying the recess and movable between a first position closing said passageway and a second position opening said passageway;
- c. a first locking means for locking said valve body in said first position to said housing and for releasing said valve body from said housing upon a predetermined force applied to said valve body;
- and
- d. piston means, attached to said valve body, including:
- seal means for sealingly contacting said recess so as to divide said recess into a negligible pressure compressible chamber isolated from both said axial bore and said annulus, and an annulus pressure chamber isolated from said axial bore but communicating with said isolated portion of said annulus and differential means for applying said predetermined force upon said valve body urging said valve body toward said second position in response to a predetermined higher pressure in said annulus pressure chamber than in said isolated negligible pressure chamber.
Dependencies are inferred from the claim text.