SUBSURFACE SAFETY VALVE Russian patent published in 2002 - IPC

FIELD: oil and gas producing industry, particularly, devices for cutting-off of producing formation from well. SUBSTANCE: subsurface safety valve includes packer with landing joint and check valve, kelly, stem, flange installed on lift string, and X-mass tree. Packer has fork installed by means of tie-rods into body recesses. Fork tie-rods are connected with bracing member located on body lower stage with seal. Tubular seal with sealing members is installed on seal and connected with body lower stage. Circular sectors with catching shoulders on landing joint are connected by screws with valve installed in its passage channel. Circular sectors are located in bore of body cover. Catching shoulders of sectors are located in windows of body upper stage for their transverse motion with conjugation of sectors with fork tubular part in process of packer fixing in sealing string coupling by joint. Circular sectors fix fork end in its motion by landing joint with internal bypass channels installed concentrically in its cavity. Landing joint and stem are connected in lower parts with joint. Joint has clamps installed in coaxial windows of joint body with possible closing-unclosing of plunger end piece in their engagement with wedge bosses of spring-loaded ring. Kelly is located in case and connected with it by subs for laying of current-supply cable between kelly and case and cable insulating from well medium by seal unit. Flange is installed between casing head and X-mass tree and connected with them by separate connectors and conjugated with kelly case by sealing member installed in flange bore. After packer lowering into well, valve in landing joint is sheared off, circular sectors are unwedged, packer is lowered to some extent. After installation of packer into well, electric centrifugal pump in assembly with liner is lowered. X-mass tree is installed on flange. Circulation windows in liner communicate producing formation of well with pump intake. EFFECT: higher operating reliability of subsurface safety valve in performance of well repairs without its killing by squeezing fluid. 4 cl, 6 dwg