Patent ID: 11952846
Assignee: SAUDI ARABIAN OIL COMPANY
Field: Civil engineering (Other fields)
Classification: CPC E | IPC E

Claim 0:
1. A rotational continuous circulation system for connection into a drill pipe string, the system including:
a circulation sub having an internal bore extending along a central axis, the circulation sub having:
an uphole connector end and a downhole connector end for connection in-line with stands of the drill pipe string;
an uphole body that is a tubular member with an uphole internal bore, the uphole body having a first outer diameter along an uphole length of the uphole body and having a reduced outer diameter along a downhole length of the uphole body;
a central valve located within the uphole internal bore and operable to selectively open and close the uphole internal bore;
at least one check valve is located within a sidewall of the uphole body and operable to selectively allow fluid to flow into the uphole internal bore through the at least one check valve;
a downhole body that is a tubular member with a downhole internal bore, an uphole portion of the downhole body circumscribing a downhole portion of the uphole body; and
a sleeve assembly circumscribing the reduced outer diameter of the uphole body; where

the uphole body and the downhole body are configured to rotate about the central axis free of relative rotation between the uphole body and the downhole body;
the uphole body and the downhole body are configured to rotate about the central axis independently from the sleeve assembly; and
a side-entry port of the sleeve assembly is operable to provide a fluid flow path from an exterior of the sleeve assembly to the at least one check valve.