Abstract: A blowout preventer includes a main housing containing a through bore. A first chamber is arranged transverse to the through bore. A second chamber is transverse to the through bore and is diametrically opposed to the first chamber. A first shearing device is located in the first chamber and a second shearing device located in the second chamber. The blowout preventer includes a charge that when activated propels each shearing device along its respective chamber and across the through bore into the opposing chamber, such that the first and second shearing devices are adjacent each other.

Abstract: A blowout preventer has a main body having a through bore. A housing is mounted to the main body and defines a passage connected to and transverse to the through bore. An isolation ring cutter is initially disposed around the through bore and closes the passage to fluid flow. The isolation ring cutter is movable along the passage and has an opening coincident with the through bore. A piston and gate are disposed in the passage spaced apart from the isolation ring cutter. A propellant charge is disposed between the piston and an end.

Abstract: A blowout preventer has a main body having a through bore. A housing is mounted to the main body and defines a passage connected to and transverse to the through bore. An isolation ring cutter is initially disposed around the through bore and closes the passage to fluid flow. The isolation ring cutter is movable along the passage and has an opening coincident with the through bore. A piston and gate are disposed in the passage spaced apart from the isolation ring cutter. A propellant charge is disposed between the piston and an end.