| 主权项 |
1. Apparatus useful for providing a liquid-tight seal around an opening formed in the earth's surface to the underground borehole of a hydrocarbon exploration or production well, the borehole having a wall extending around it, downwardly below the earth's surface and not above the earth's surface, the borehole wall having a top edge, the apparatus comprising:
a clamp configured to be positioned inside the borehole proximate to the opening thereof and firmly engage the inside of the borehole wall around the entirety of the borehole, said clamp comprising at least first and second interconnectable sections, each said clamp section having an inwardly projecting connection bracket proximate to each end thereof, respectively, each said connection bracket of each said clamp section being releasably engageable with one of said connection brackets of another said clamp section to connect said clamp sections together and firmly engage the borehole wall; at least one platform configured to extend outwardly from the top of said clamp relative to the borehole, over the top edge of the borehole wall and across the earth's surface adjacent to and around the borehole when said clamp is engaged with the borehole wall; and at least one seal member configured to be disposed between the borehole wall and at least one among said clamp and said platform to form a liquid-tight seal therebeteween, wherein liquid exiting the borehole through the borehole opening is prevented from contacting the earth around the borehole opening. |
