초록 ▼

A method is provided for controlling operation of a subsurface hydraulically operated well tool. In a described embodiment, a surface controlled subsurface safety valve is controlled utilizing two control lines. The control lines are hydraulically connected to respective ones of two pistons in the s

A method is provided for controlling operation of a subsurface hydraulically operated well tool. In a described embodiment, a surface controlled subsurface safety valve is controlled utilizing two control lines. The control lines are hydraulically connected to respective ones of two pistons in the safety valve. Pressure applied to either of the two pistons is capable of independently operating the safety valve. In normal operation, pressure is applied to both of the pistons. However, when a failure occurs in one of the control lines, the other may still be used to operate the safety valve.

대표청구항 ▼

1. A method of controlling a subsurface hydraulically actuated well too, the method comprising the steps of:hydraulically connecting a first control line to a first piston of the well tool, the well tool being operable in response to pressure in the first control line; hydraulically connecting a sec

1. A method of controlling a subsurface hydraulically actuated well too, the method comprising the steps of:hydraulically connecting a first control line to a first piston of the well tool, the well tool being operable in response to pressure in the first control line; hydraulically connecting a second control line to a second piston of the well tool, the well tool being operable in response to pressure in the second control line; operating the well tool by simultaneously applying pressure to both of the first and second control lines; and then, in response to failure of the first control line, operating the well tool by applying pressure only to the second control line.