Well tools

Claim 2

A well tool for controlling fluid flow in a tubing string in a well bore comprising: a housing having a longitudinal bore therethrough for flow of fluids; a valve secured at the lower end of said housing for movement between open and closed positions for controlling the flow of fluids into said bore of said housing; a valve operator tube supported for longitudinal movement in said Housing, a lower end of said operator tube being engageable with said valve for moving said valve from a closed to an open position responsive to downward movement of said operator tube; means associated with said operator tube for biasing said tube upwardly to an upper position at which said valve is closed; means for selectively urging said operator tube downwardly to a lower position for opening and holding said valve open; and means associated with said operator tube in said housing for equalizing the pressure across said valve when said valve is closed to reduce the force required for opening said valve including first and second equalizing valve means, said first and second equalizing valve means being opened and closed in a sequence adapted to prevent flow cutting of said first equalizing valve means.

Claim 3

A well tool in accordance with claim 1 wherein said second equalizing valve means opens after the opening of said first equalizing valve means during the opening of said valve and said second equalizing valve means closes in advance of the closing of said first equalizing valve means during the closing of said valve.

Claim 4

A well tool in accordance with claim 2 wherein said first equalizing valve means comprises an annular resilient ring seal disposed in an internal annular recess of said housing and an external annular flange on said operator tube engageable with said resilient seal when said tube is at a position at which said valve is closed and said second equalizing valve means includes an annular tapered valve seat within said housing around said operator tube between said first equalizing valve means and said valve and a sleeve member having an annular tapered seat engageable with said seat of said housing, means biasing said sleeve member toward said housing seat, and means on said operator tube for engaging and retracting said sleeve to open said second equalizing valve means by pulling said sleeve valve seat away from said housing valve seat after said first equalizing valve means is opened.

Claim 5

A well tool in accordance with claim 3 including a spring around said operator tube within said housing engaged at one end with a flange in said housing and at the other end with said sleeve member of said second equalizing valve means comprising said means for biasing said sleeve member toward said valve seat in said housing whereby said sleeve remains engaged with said seat until said flange on said valve operator tube is disengaged from said resilient seal during the opening of said valve and said sleeve member re-engages said valve seat in said housing in advance of the engagement of said valve operator tube flange with said resilient seal during the closing of said valve.

Claim 6

A well tool in accordance with claim 3 including a spring on said valve operator tube engaged between said sleeve member of said second equalizing valve means and said valve operator tube comprising said means for biasing said sleeve member toward said valve seat of said housing whereby said second equalizing valve means remains closed until said first equalizing valve means is opened and said second equalizing valve means closes in advance of the closing of said first equalizing valve means.

Claim 7

A well tool in accordance with claim 1 wherein: said means for urging said operator tube downwardly includes a piston on said valve operator tube, an annular control fluid chamber around said valve operator tube within said housing, said piston being movable in said control fluid chamber, and means for supplying a control fluid into said chamber for applying a control fluid pressure to said piston for moving said valve operator tube toward said valve to open said valve; and said means for equalizing the pressure across said valve when said valve is closed includes means defining a side port in said housing to communicate with a well bore around said well tool, means providing a port in said valve operator tube communicating with the bore of said well tool, means defining an annular flow space aroUnd said operator tube within said housing between said side port in said housing and said side port in said operator tube, said first and second equalizing valve means being positioned along said annular space between said side ports for controlling flow between said ports within said annular space to equalize the pressure between the bore of said well tool above said valve and a well bore around said well tool housing, said first and second equalizing valve means being operable responsive to longitudinal movement of said valve operator tube and including a resilient internal annular seal within an annular recess of said housing around said valve operator tube, an external annular tapered first flange on said valve operator tube engageable with said resilient seal when said flange is longitudinally aligned with said seal forming said first valve means, an internal annular tapered metal valve seat within said housing between said resilient seal and said valve, a valve sleeve member movably disposed on said operator tube within said annular space and having an annular tapered valve seat engageable with said housing valve seat forming said second equalizing valve means, a second external annular flange on said valve operator tube spaced from said first flange and movable within said valve sleeve member for actuating said valve sleeve member relative to said housing seat, said sleeve member having an internal annular operator shoulder facing said valve engageable by said second flange on said operator tube limiting movement of said operator tube away from said valve at a position to align said first flange within said resilient seal, said sleeve member having means providing internal operating surfaces facing away from said valve for engagement by said second flange on said operator tube to move said sleeve member toward said valve to open said second equalizing valve means, the distance between said operator shoulder of said member and said operator surfaces being greater than the length of said second flange on said second flange on said operator tube whereby said first equalizing valve means opens before said second flange engages said valve sleeve member to open said second equalizing valve means and a spring engaged with said valve sleeve member biasing said valve sleeve away from said valve toward said valve housing seat.

Claim 8

A well tool in accordance with claim 6 wherein said spring is confined between a shoulder in said housing facing away from said valve and the end of said valve sleeve member facing said valve.

Claim 9

A well tool in accordance with claim 6 wherein said valve sleeve member is provided with resilient collet fingers projecting toward the valve, said collet fingers having inwardly turned collet heads defining said internal operating shoulder in said valve sleeve member and a spring confined within said valve sleeve member around said valve operator tube between said flange on said operator tube and said operator shoulder in said valve sleeve member facing said valve providing means biasing said valve sleeve toward said housing seat on said valve operator tube.