Valve actuator
AssigneeCanrig Drilling Technology Ltd.
InventorsLemuel T. York, Allan S. Richardson, Beat Kuttel
Life of this patent
Estimating the term…
Abstract
A valve actuator is provided in which a complementary set of pinions, each driven by a pair of racks, are located on opposite sides of the valve to be actuated. The racks are part of an annular bearing assembly and are coupled to one another through a hydraulic cylinder or some other displacement device. A pinion retaining shield is provided to shield the racks and pinions and prevents parts of the valve actuator from being thrown in operation. The piston retaining shield may include a maintenance aperture for installing or repairing a pinion and a second aperture for viewing the rotation of the pinion. The bearing assemblies each include a bearing housing and a bearing retainer ring that cooperate to shield the bearing assembly.
Claims26
A valve actuator for opening or closing a valve, comprising:
- at least two pinions, at least two of which are located opposite one another and include a crank opening at the axis of the pinion for closing the valve;
- for each pinion, at least two racks cooperating with each pinion and operable to rotate the pinion about its axis;
- a pinion retaining sleeve covering the pinions and racks;
- and
- wherein the valve actuator rotates at the same speed as the valve.
A valve actuator, comprising:
- first and second annular bearing assemblies, each of said annular bearing assemblies sized to encircle a valve to be actuated, each of said bearing assemblies including first and second racks, wherein the first rack of the first annular bearing assembly and the second of the second bearing assembly operate to turn a first pinion positioned on a first side of the valve actuator, and wherein a second rack of the first bearing assembly and a first rack of the second bearing assembly operate to turn a second pinion positioned on the second side of the valve actuator;
- wherein each of the first and second pinions include a crank hole;
- and
- a displacement device coupled between the first and second bearing assemblies to move the first and second bearing assemblies between two positions relative to each other and the body of the valve to be actuated, wherein the first position causes a valve to be actuated to be closed and the second position causes a valve to be actuated to be open.
A method for actuating a valve, comprising the steps of:
- coupling a valve actuator to the valve, the valve actuator comprising,
- first and second annular bearing assemblies, each of said annular bearing assemblies sized to encircle a valve to be actuated, each of said bearing assemblies including first and second racks, wherein the first rack of the first annular bearing assembly and the second of the second bearing assembly operate to turn a first pinion positioned on a first side of the valve actuator, and wherein a second rack of the first bearing assembly and a first rack of the second bearing assembly operate to turn a second pinion positioned on the second side of the valve actuator;
- wherein each of the first and second pinions include a crank hole;
- and
- a cylinder coupled between the first and second bearing assemblies to move the first and second bearing assemblies between two positions relative to each other and the body of the valve to be actuated, wherein the first position causes a valve to be actuated to be closed and the second position causes a valve to be actuated to be open;
- activating the cylinder to cause the racks of the first and second bearing assemblies to move relative to one another to rotate the pinion, wherein the rotation of the pinion causes the valve to open or close depending on the direction of rotation of the pinion.
Dependencies are inferred from the claim text.