National Oilwell Varco, L.p.

Derek James Stuart

Alan Martyn Eddison

Alan H Kitching

David Anderson Coull

A pulse generator comprises a stator coupled to a housing and a rotor that is rotatably disposed within the housing. An annulus is formed between the rotor and the stator. An inner bore is formed through the rotor. One or more outer flow ports provide fluid communication between the annulus and the inner bore. A retrievable valve assembly is rotationally coupled to the rotor and at least partially disposed within the inner bore. The retrievable valve assembly includes a rotary valve member having one or more primary flow ports. A fluid flow path is periodically formed by the one or more outer flow ports, the annulus, and the one or more primary flow ports as the rotor rotates.

Downhole pulse generating device

A method of translating a member through a bore involving moving fluid through a tubular member such as a drill string, and generating impulses on the member by varying the passage of fluid through the member using a valve which opens at a first rate and closes at a different second rate to urge the member to advance in a selected direction. The valve may close quickly and open slowly, or may close slowly and open quickly.

Growing community of inventors

Aberdeen, United Kingdom

Derek James Stuart