METHOD AND APPARATUS FOR FACILITATING CONTINUOUS CIRCULATION OF DRILLING MUD DURING CONSTRUCTION AND MAINTENANCE OF A WELL

摘要

A method for facilitating continuous circulation of drilling mud duringconstruction and maintenance of a well,the method comprising the steps of moving a housing (102) of a continuouscirculation tool (100) to a sub (10) having a bore (14)therethrough, the sub (10) in or for connection in a string of tubular s inthe well and selectively allowing drilling mud to flow betweenthe housing (102) and a side opening (13) in the sub (10), the continuouscirculation tool (100) further comprising a closure apparatus(40), activating a closure mechanism (41,44) to insert a closure member (42)of the closure apparatus (40) through the side opening(13) in the sub (10) to isolate of drilling fluid through at least a portionof the bore (14). Also disclosed in a system for continuouscirculation wellbore operations, the system comprising a continuouscirculation tool (100) positionable in fluid communication witha wellbore tubular string comprising a sub (10) therein, the continuouscirculation tool (100) for selectively closing off flow to thewellbore tubular string, tubular manipulation apparatus (202) adjacent thesub, and the tubular manipulation apparatus comprisingone of tong, tongs, tong and back-up, tong and spinning wrench, and ironroughneck.