Method of using a subsurface safety valve
AssigneeHydril Company
InventorJames D. Mott
Life of this patent
Estimating the term…
Abstract
A pressure operated safety valve adapted to be mounted in a well tubing, which may be moved to open or closed positions independently of pressure in the tubing and locked in and unlocked from the open position using control fluid pressure.
Claims20
A method of regulating flow through a well tubing with a subsurface safety valve having a controllable stopper operating independently of the pressure in the tubing comprising the step of:
- forming a pressure differential independent of well tubing pressure between first and second expansible control chambers formed by the valve when a greater pressure is selectively introduced in one of either first and second expansible chambers to control the movement of the stopper;
- and
- adjusting the position of the stopper in response to the pressure differential between the first and second chambers to enable flow through the well tubing when the greater pressure is selectively introduced into one of either of the first and second expansible chambers.
A method of operating a controllable valve having a movable stopper for controlling flow through a well tubing at a subsurface location in the well in response to use of one of first and second controls from the surface to open the valve, comprising the steps of:
- moving the stopper to an open position by selective use of one of the first and second controls of the valve at the surface independent of the well tubing for enabling flow to the surface through the well tubing;
- and
- locking the stopper in the open position when the second control is selectively used for moving the stopper to the open position.
The method of operating a safety valve having a movable stopper for controlling flow through a well tubing at a subsurface location, comprising the steps of:
- moving the stopper to an open position for enabling flow through the well tubing by selective use at the surface independent of the well tubing of one control of a first control and a second control;
- and
- locking in an unlockable manner the stopper in the open position when the second control is used to move the stopper to the open position.
A method of operating a safety valve having a movable stopper for controlling flow through a well tubing at a subsurface location, comprising the steps of:
- moving the stopper to an open position for enabling flow through the well tubing by selective use at the surface independent of the well tubing of one control of a first control and a second control;
- locking in an unlockable manner the stopper in the open position when the second control is used to move the stopper to the open position;
- and
- unlocking the stopper from the open position with the first control.
The method of regulating flow through a well tubing with a subsurface safety valve having a controllable stopper comprising the steps of:
- forming a pressure differential between first and second expansible control chambers provided by the safety valve independent of the well tubing when a greater pressure is selectively introduced in one of either the first and second expansible chambers;
- and
- adjusting the position of the stopper in response to the pressure differential provided by increased pressure in one of either the first and second expansible chambers to enable flow through the well tubing.
The method of operating from the surface a controllable valve having a movable stopper for controlling flow through a well tubing at a subsurface location, comprising the steps of:
- providing a first control having a control conduit communicating to the controllable valve from the surface for operation to move the stopper to the open position for enabling flow through the well tubing;
- providing a second control having a control conduit communicating to the controllable valve from the surface for operation to move the stopper to the open position for enabling flow through the well tubing;
- and
- operating selectively one of the first and second controls at the surface to move the stopper to the open position to enable flow through the well tubing.
Dependencies are inferred from the claim text.