| 摘要 |
<p>A system for providing a barrier between two different fluid densities in a riser while drilling in deep water. An internal housing (20) and a rotating control head (28) are positioned in a first housing (R) when a blowout preventer (GM) is in the sealed position. When the blowout preventer is in the sealed position about the internal housing, a pipe (P) can be rotated for drilling with the pressure of the fluid in the open borehole at one density (M) and the fluid above the seal at another density (SW). When the blowout preventer seal is in the open position, the threadedly connected bearing assembly and internal housing can be removed relatively quickly from the riser (R). Advantageously, a method for use of the system is also disclosed.</p> |
