WELLBORE CIRCULATION SYSTEM, KELLY BUSHING, KELLY AND TONG

摘要

A system (10) for continuously circulating fluid to and through a tubular string either of coiled tubing or made up of a plurality of tubulars connected end-to-end while an upper tubular (32) is added to or removed from a top tubular (26) of the plurality of tubulars, all tubulars having a top-to-bottom fluid flow channel therethrough. The system has an upper chamber (43) with an upper sealing apparatus (34) for sealingly encompassing a portion of the upper tubular, a lower chamber (45) with a lower sealing apparatus (36) for sealingly encompassing a portion of the top tubular (26), one of the upper chamber and the lower chamber sized for accommodating connection and disconnection therein of the upper tubular and the top tubular, and gate apparatus (60) between and in fluid communication with the upper chamber and the lower chamber.