Patent ID: 11959349
Assignee: NATIONAL OILWELL VARCO, L.P.
Field: Civil engineering (Other fields)
Classification: CPC E | IPC E

Claim 0:
1. A pressure pulse system disposable in a wellbore, comprising:
a stator comprising a plurality of helical stator lobes;
a rotor rotatably positioned in the stator and comprising a plurality of helical rotor lobes; and
a valve assembly coupled to the stator and to the rotor and configured to induce a pressure pulse in response to rotation of the rotor within the stator, wherein the valve assembly comprises:
a first valve plate coupled to one of the stator and the rotor and comprising a flow passage; and
a second valve plate coupled to the other of the stator or the rotor to which the first valve plate is not coupled and comprising a first flow passage and a second flow passage that is spaced from the first flow passage of the second valve plate, wherein a central axis of the first valve plate is offset from a central axis of the second valve plate whereby the second valve plate is configured to rotate eccentrically relative to the first valve plate;
wherein the valve assembly comprises a first configuration that provides a first flowpath between the flow passage of the first valve plate and the second flow passage of the second valve plate, and wherein the second flow passage of the second valve plate is encompassed entirely within the flow passage of the first valve plate in an end view when the valve assembly is in the first configuration;
wherein the valve assembly comprises a second configuration that provides a second flowpath between the flow passage of the first valve plate and the first flow passage of the second valve plate.