SYSTEMS AND METHODS FOR MANAGING PRESSURE IN A WELLBORE

摘要

A method for drilling a subsea well 130 from a rig through a subsea wellhead 122 below the rig includes employing a single gradient or dual gradient drilling system that includes a drill string 136 that extends from the rig into the well and surface mud pumps for pumping drilling fluid through the drill string 136 and into a well annulus 150 of the well. The drilling system includes a subsea rotating device 110 for conducting the drilling fluid from the well annulus 150 and through a solids processing unit 114. A subsea pump 108 then conducts the drilling fluid from the solids processing unit 114 to a return line 20 back to the rig. The surface mud pump and subsea pump 108 are staged in coordination to trap pressure and/or remove pressure in the well annulus 150 to maintain a selected pressure gradient in the well annulus.