Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: The wireline release includes a shaft having one end releasably connected to the end of the wireline by a connector and being held in the latched position by a fusible material ring. Upon activating heaters in the cable head from the surface via conductors in the wireline, the fusible material ring is melted allowing the shaft, under the tension of the wireline, to shift to an unlatched position whereby the connector releases the wireline from the shaft and cable head. The connector includes a plurality of collet members which, in the latched position, are biased into the connection with the end of the wireline and are then released upon being shifted to the unlatched position where the collet members move to a disengaged position.