SYSTEMS AND METHODS FOR MANAGING PRESSURE IN A WELLBORE

摘要

A method for drilling a subsea well from a rig through a subsea wellhead below the rig includes employing a single gradient or dual gradient drilling system that includes a drill string that extends from the rig into the well and surface mud pumps for pumping drilling fluid through the drill string and into a well annulus of the well. The drilling system includes a subsea rotating device for conducting the drilling fluid from the well annulus and through a solids processing unit. A subsea pump then conducts the drilling fluid from the solids processing unit to a return line back to the rig. The surface mud pump and subsea pump are staged in coordination to trap pressure and/or remove pressure in the well annulus to maintain a selected pressure gradient in the well annulus.