| 摘要 |
A blowout preventer (100) to hydraulically seal a wellbore includes a housing (102) configured to be positioned above a wellhead and to surround a drillstring (112), a plurality of rams (120) positioned perpendicular to an axis (114) of the drillstring to engage the drillstring (112) and hydraulically isolate an annulus (116) between the wellbore and the drillstring (112) when in a closed position, and a roller lock (350, 250) positioned about a thrust rod (326, 226, 126) of each ram (120) configured to maintain the rams (120) in the closed position. |
