| 摘要 |
An improved blowout preventer having a body with a vertical bore and opposed aligned guideways extending out from the bore, a pair of studs secured to the body, one at each side of each guideway and extending into the bonnets closing the guideways, a cylinder in each bonnet, a piston in each cylinder, a rod extending from each piston and connecting to a ram in its guideway, pressure responsive means connecting between the body and each bonnet for urging the bonnets toward and away from the body, nuts rotatable and captured in the bonnets and threaded onto the studs to retain the bonnets in position on the body and means for supplying hydraulic pressure to the cylinders to move the rams and to the pressure responsive means to move the bonnets. In one form of the invention, the studs coact as a part of the pressure responsive means for urging the bonnets toward the body and are hydarulically tensioned thereby. |
