发明名称 |
Drilling system and method for controlling equivalent circulating density during drilling of wellbores |
摘要 |
A drilling system for drilling subsea wellbores includes a tubing-conveyed drill bit that passes through a subsea wellhead. Surface supplied drillng fluid flows through the tubing, discharges at the drill bit, returns to the wellhead through a wellbore annulus, and flows to the surface via a riser extending from the wellhead. A flow restriction device positioned in the riser restricts the flow of the returning fluid while an active fluid device controllably discharges fluid from a location below to just above the flow restriction device in the riser, thereby controlling bottomhole pressure and equivalent circulating density ("ECD"). Alternatively, the fluid is discharged into a separate return line thereby providing dual gradient drilling while controlling bottomhole pressure and ECD. A controller controls the energy and thus the speed of the pump in response to downhole measurement(s) to maintain the ECD at a predetermined value or within a predetermined range. |
申请公布号 |
GB2389130(B) |
申请公布日期 |
2006.01.11 |
申请号 |
GB20030005720 |
申请日期 |
2002.07.09 |
申请人 |
BAKER HUGHES INCORPORATED |
发明人 |
PETER FONTANA;PETER S ARONSTAM;LARRY WATKINS |
分类号 |
E21B7/12;E21B21/00;E21B21/08;E21B33/076;E21B43/12;E21B47/00 |
主分类号 |
E21B7/12 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|