Improved annulus pressure operated well testing apparatus and its method of operation

Claim 1

A method for conducting formation testing utilizing a formation testing string; a formation testing valve assembly incorporated in a lower portion of said formation testing string; and a packer assembly incorporated in a lower portion of said formation testing string and operable to isolate a formation to be tested from an upper portion of a well bore within which said formation testing string is positioned, with said formation testing valve assembly being operable to control a flow of formation fluid between said formation and the interior of said formation testing string; said method being characterized by improvements in testing valve operation comprising: providing full opening formation testing valve means in said formation testing valve assembly operable to move between closed and open conditions, said full opening formation testing valve means, in said open condition, being operable to provide a formation fluid transmitting opening extending generally centrally and longitudinally of said formation testIng string; providing annulus pressure responsive, full opening formation testing valve closing means in said formation testing valve and having first, annulus pressure responsive, force generating means operably responsive to the pressure of fluid in an annulus in a well bore generally adjacent said formation testing valve assembly to generate in said well bore a first biasing force, and first, annulus pressure responsive, force transmitting means operable to transmit said first annulus pressure generated biasing force to said full opening formation testing valve means and urge said full opening formation testing valve means to said closed condition; providing annulus pressure responsive, full opening formation testing valve opening means in said formation testing valve assembly and having second, annulus pressure responsive, force generating means operably responsive to the pressure of fluid in said annulus of said well bore generally adjacent said formation testing valve assembly to generate in said well bore a second biasing force, and second, annulus pressure responsive, force transmitting means operable to transmit said second annulus pressure generated biasing force to said full opening formation testing valve means and urge said full opening formation testing valve means to said open condition; and operating said annulus pressure responsive, full opening formation testing valve closing means, said annulus pressure responsive, full opening formation testing valve opening means, and said full opening formation testing valve means in combination to provide said closed and open conditions in response to changes in fluid pressure in said annulus while permitting a relatively unobstructed flow of formation fluid generally centrally and longitudinally of said formation testing string through said formation testing valve assembly when said full opening formation testing valve means is in said open condition.

Claim 2

A method for conducting formation testing utilizing a formation testing string; a formation testing valve assembly incorporated in a lower portion of said formation testing string; and a packer assembly incorporated in a lower portion of said formation testing string and operable to isolate a formation to be tested from an upper portion of a well bore within which said formation testing string is positioned, with said formation testing valve assembly being operable to control a flow of formation fluid between said formation and the interior of said formation testing string; said method being characterized by improvements in testing valve operation comprising: providing full opening formation testing valve means in said formation testing valve assembly operable to move between closed and open conditions, said full opening formation testing valve means, in said open condition, being operable to provide a formation fluid transmitting opening extending generally centrally and longitudinally of said formation testIng string; providing annulus pressure responsive, full opening formation testing valve closing means in said formation testing valve and having first, annulus pressure responsive, force generating means operably responsive to the pressure of fluid in an annulus in a well bore generally adjacent said formation testing valve assembly to generate in said well bore a first biasing force, and first, annulus pressure responsive, force transmitting means operable to transmit said first annulus pressure generated biasing force to said full opening formation testing valve means and urge said full opening formation testing valve means to said closed condition; providing annulus pressure responsive, full opening formation testing valve opening means in said formation testing valve assembly and having second, annulus pressure responsive, force generating means operably responsive to the pressure of fluid in said annulus of said well bore generally adjacent said formation testing valve assembly to generate in said well bore a second biasing force, and second, annulus pressure responsive, force transmitting means operable to transmit said second annulus pressure generated biasing force to said full opening formation testing valve means and urge said full opening formation testing valve means to said open condition; and operating said annulus pressure responsive, full opening formation testing valve closing means, said annulus pressure responsive, full opening formation testing valve opening means, and said full opening formation testing valve means in combination to provide said closed and open conditions in response to changes in fluid pressure in said annulus while permitting a relatively unobstructed flow of formation fluid generally centrally and longitudinally of said formation testing string through said formation testing valve assembly when said full opening formation testing valve means is in said open condition.

Claim 6

An apparatus for conducting formation testing including a formation testing string; a formation testing valve assembly incorporated in a lower portion of said formation testing string; a packer assembly incorporated in a lower portion of said formation testing string and operable to isolate a formation to be tested from an upper portion of a well bore within which said formation testIng string is positioned, with said formation testing valve assembly being operable to control a flow of formation fluid between said formation and the interior of said formation testing string; said apparatus being characterized by improvements in said formation testing valve assembly comprising: full opening formation testing valve means included in said formation testing valve assembly and movable between closed and open conditions, said full opening formation testing valve means, in said open condition, being operable to provide a formation fluid transmitting opening extending generally centrally and longitudinally of said formation testing string; and annulus pressure responsive, full opening formation testing valve opening means included in said formation testing valve assembly and having annulus pressure responsive, force generating means operably responsive to the pressure of fluid in said annulus of said well bore generally adjacent said formation testing valve assembly to generate in said well bore a biasing force, and annulus pressure responsive, force transmitting means operable to transmit said annulus pressure generated biasing force to said full opening formation testing valve means and urge said full opening formation testing valve means to said open condition; said annulus pressure responsive, full opening formation testing valve opening means, and said full opening formation testing valve means being operable to provide said open condition in response to a change in fluid pressure in said annulus while permitting a relatively unobstructed flow of formation fluid generally centrally and longitudinally of said formation testing string through said formation testing valve assembly when said full opening formation testing valve means is in said open condition; said full opening formation testing valve means including a rotary ball valve, and a housing supporting said rotary ball valve in generally fixed longitudinal position within said formation testing valve assembly; and said annulus pressure responsive, force transmitting means includes arm means extending generally longitudinally of said formation testing string and operable to undergo longitudinal and circumferential movement relative thereto, recess means carried by said rotary ball valve, extending generally radially of the outer periphery thereof and located eccentrically thereon, and lug means carried by said arm means and rotatably and slidably received by said recess means, said arm means being operable, in response to an imposition of longitudinal force thereon by said annulus pressure responsive force generating means, to transmit rotary movement inducing force through said lug means and recess means to said rotary ball valve while being free to move longitudinally and circumferentially of said formation testing string as the position of said recess means changes during rotation of said rotary ball valve.

Claim 7

An apparatus for conducting formation testing including a formation testing string; a formation testing valve assembly incorporated in a lower portion of said formation testing string; a packer assembly incorporated in a lower portion of said formation testing string and operable to isolate a formation to be tested from an upper portion of a well bore within which said formation testIng string is positioned, with said formation testing valve assembly being operable to control a flow of formation fluid between said formation and the interior of said formation testing string; said apparatus being characterized by improvements in said formation testing valve assembly comprising: full opening formation testing valve means included in said formation testing valve assembly and movable between closed and open conditions, said full opening formation testing valve means, in said open condition, being operable to provide a formation fluid transmitting opening extending generally centrally and longitudinally of said formation testing string; and annulus pressure responsive, full opening formation testing valve opening means included in said formation testing valve assembly and having annulus pressure responsive, force generating means operably responsive to the pressure of fluid in said annulus of said well bore generally adjacent said formation testing valve assembly to generate in said well bore a biasing force, and annulus pressure responsive, force transmitting means operable to transmit said annulus pressure generated biasing force to said full opening formation testing valve means and urge said full opening formation testing valve means to said open condition; said annulus pressure responsive, full opening formation testing valve opening means, and said full opening formation testing valve means being operable to provide said open condition in response to a change in fluid pressure in said annulus while permitting a relatively unobstructed flow of formation fluid generally centrally and longitudinally of said formation testing string through said formation testing valve assembly when said full opening formation testing valve means is in said open condition; said full opening formation testing valve means including a rotary ball valve, and a housing supporting said rotary ball valve in generally fixed longitudinal position within said formation testing valve assembly; and said annulus pressure responsive, force transmitting means includes arm means extending generally longitudinally of said formation testing string and operable to undergo longitudinal and circumferential movement relative thereto, recess means carried by said rotary ball valve, extending generally radially of the outer periphery thereof and located eccentrically thereon, and lug means carried by said arm means and rotatably and slidably received by said recess means, said arm means being operable, in response to an imposition of longitudinal force thereon by said annulus pressure responsive force generating means, to transmit rotary movement inducing force through said lug means and recess means to said rotary ball valve while being free to move longitudinally and circumferentially of said formation testing string as the position of said recess means changes during rotation of said rotary ball valve.