초록 ▼

A subsurface well tool having a hydraulic piston and cylinder assembly actuator which is adapted to be connected to and controlled by a hydraulic control line extending to the well surface. The assembly has a cross-sectional area exposed to the hydraulic control fluid which increases in one directio

A subsurface well tool having a hydraulic piston and cylinder assembly actuator which is adapted to be connected to and controlled by a hydraulic control line extending to the well surface. The assembly has a cross-sectional area exposed to the hydraulic control fluid which increases in one direction of movement of the assembly and decreases in the opposite direction for reducing surface operating pressure problems. Preferably, one of the piston and cylinder includes a tapered surface, and includes a flexible seal between the piston and cylinder.

대표청구항 ▼

In a subsurface well tool having a housing and a hydraulic piston and cylinder assembly actuator, the improvement in the actuator comprising, said piston and cylinder assembly adapted to be connected to a hydraulic control line extending to the well surface, said cylinder assembly including an inlet

In a subsurface well tool having a housing and a hydraulic piston and cylinder assembly actuator, the improvement in the actuator comprising, said piston and cylinder assembly adapted to be connected to a hydraulic control line extending to the well surface, said cylinder assembly including an inlet connected to said hydraulic control line, and said assembly having a cross-sectional area exposed to hydraulic fluid in the control line, said area increasing in one direction of movement of the assembly and decreasing in the opposite direction.