Patent ID: 8505635

Claim:
A device comprising: a top drive; a self-contained and releasable drive shaft assembly which is arranged for both driven insertion into and retrieval from the top drive and connectable to a first end portion of a drill pipe, said drive shaft assembly is provided with a centre bore extending therethrough, said center bore is arranged for fluid communication between a drilling mud plant and a fluid bore of the drill pipe; a connection housing including a first chamber and a second chamber, said connection housing is integrated as part of the top drive for synchronous movement with the top drive; the first chamber being provided with a releasable, drive-shaft/pipe-surrounding first pressure seal; the second chamber being provided with a releasable, drill-string-surrounding second pressure seal; and an interface between the first and second chambers being made up of a valve which is arranged to provide, in an open position, a passage for the drill pipe or drive shaft; and a drilling mud inlet arranged for the second chamber and arranged for fluid communication between the drilling mud plant and the connection housing; wherein the drive shaft assembly and the connection housing enable continuous circulation of drilling mud during drilling operations.