| 摘要 |
A shearing apparatus for installation on a wellhead and having capability of shearing drill collars. The improved apparatus includes a body with a vertical bore therethrough and ram guideways extending laterally from opposite sides of the bore, a pair of rams, each positioned in one of the guideways, each ram including a cutting blade, reciprocating means secured to each ram for moving the rams and their cutting blades into the vertical bore to shear tubular members therein and to retract the rams and cutting blades into the guideways, the reciprocating means having sufficient power to cause the cutting blades to shear large diameter casing and drill collars, and arms secured to the sides of the rams and extending toward the other ram, said arms engaging as the rams are moved toward the bore and providing a force resisting the forces tending to vertically separate the cutting blades during shearing, said arms also substantially filling the space of the guideways outside the vertical bore to prevent the forcing of members being sheared into this space. |
