Abstract: A method of completing a well includes lowering a wellhead onto a base at an upper end of the well. A hub with internal threads and an external circumferential stepped recess is secured to external threads of the wellhead. A blowout preventer assembly with an annular locking member having a plurality of locking elements is landed on the hub, and the locking elements are engaged with the recess of the hub. The well is drilled through the blowout preventer assembly to a greater depth then the blowout preventer assembly and the hub are removed. A threaded flange with a plurality of bolt holes spaced around the flange is secured to the external threads of the wellhead and a wellhead member is bolted to the bolt holes of the threaded flange.

Abstract: A method of completing a well includes Lowering a wellhead onto a base al as upper end of the well. A hub with internal threads and an external circumferential stepped recess is secured to external threads of the wellhead. A blowout preventer assembly with an annular locking member having a plurality of locking demerits is landed on the hub, and the looking elements are engaged with the recess of the hub. The well is drilled through the blowout preventer assembly to a greater depth then the blowout preventer assembly and the hub are removed. A threaded flange with & plurality of bolt holes spaced around die flange is secured to the external threads of the wellhead and a wellhead member is bolted to the bolt holes of the threaded flange.

Abstract: A A wellbore system includes a hub and an annular locking member. The hub can be adapted to couple to a wellhead. The annular locking member can couple to an external diameter of a blowout preventer assembly. The annular locking member can include a plurality of locking elements configured to couple the annular locking member to the hub. Further a method of completing a well includes lowering a wellhead onto a base at an upper end of the well. A hub with internal threads and an external circumferential stepped recess is secured The method can include securing the hub to external threads of the wellhead. A The method further includes landing a blowout preventer assembly with an annular locking member having a plurality of locking elements is landed on the hub, and the locking elements are engaged and engaging the annular locking member with the recess of the hub.