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 during construction and maintenance of a well, the method comprising the steps of moving a housing (102) of a continuous circulation tool (100) to a sub (10) having a bore (14) therethrough, the sub (10) in or for connection in a string of tubular s in the well and selectively allowing drilling mud to flow between the housing (102) and a side opening (13) in the sub (10), the continuous circulation 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 portion of the bore (14). Also disclosed in a system for continuous circulation wellbore operations, the system comprising a continuous circulation tool (100) positionable in fluid communication with a wellbore tubular string comprising a sub (10) therein, the continuous circulation tool (100) for selectively closing off flow to the wellbore tubular string, tubular manipulation apparatus (202) adjacent the sub, and the tubular manipulation apparatus comprising one of tong, tongs, tong and back-up, tong and spinning wrench, and iron roughneck.