| 摘要 |
<p>A specialized large diameter, low pressure, subsea blowout preventer stack for drilling deep water wells from a floating drilling vessel is conveyed to the subsea wellhead on a unique, drill pipe riser. The combination of the two elements and the unique method using the same allows the driller to start a subsea well with larger diameter casing, and to control shallow flow zones often encountered in deep water wells. The unique combination of existing elements and novel method allows the driller the option of allowing mud to return to the sea floor, or of establishing circulation with mud returned to the floating rig.</p> |
