An autonomous BOP system is provided for stopping an uncontrolled flow of formation hydrocarbons comprising two or more sensors distributed along a length of a subsea blowout preventer to monitor a drill pipe inside a blowout preventer and measure critical parameters. A computer using predictive-software monitors a blowout preventer along with material critical parameters and calculates a blowout preventer configuration and sequence to arrest a well blowout. Blowout preventer components are fine-tuned and operational modes are added to aid an arrest of a well blowout under realistic conditions.

A blowout preventer (BOP) includes a main body comprising a bore extending therethrough and a pair of opposing upper and lower rams configured to shear a tubular extending through the bore. The upper ram includes a first sloped surface oriented crosswise to a vertical axis, the lower ram comprises a second sloped surface oriented crosswise to the vertical axis, and the first sloped surface and the second sloped surface are parallel to one another.

The method of providing blowout preventer shear rams which will shear pipe then provide a face-to-face compression seal comprising providing an upper shear ram having an upper shear ram blade and a pipe lifter, providing a lower shear ram having a lower shear ram blade, and a pipe lifter, providing a face-to-face seal, moving the upper and lower shear rams into the bore towards one another, shearing the pipe in the bore of the blowout preventer, engaging the upper sheared portion of the pipe with the pipe lifters, lifting the upper sheared portion of the pipe with the pipe lifters to a position above the face-to-face seal, engaging the face-to-face compression seal to effect a seal across the bore.

The method of preventing pressures higher than a predetermined pressure in the front ram seals of blowout preventer rams comprising providing blowout preventer rams suitable for sealing across the bore of a blowout preventer stack, providing seals on the blowout preventer rams which sealingly isolate the bore area below or upstream of the blowout preventer rams from the area above or downstream of the blowout preventer rams, providing a passageway from the front to the rear of the blowout preventer rams to vent the upstream or higher pressures to the rear of the blowout preventer rams, and communicating the resilient seal material in the front ram seals with a pressure release piston which will relieve the pressure at the predetermined pressure.

A blade includes a blade body extending a blade length and having a blade depth. The blade also includes a flat, arranged at a forward face, extending a flat length, less than the blade length. The blade further includes at least one slant, arranged at the forward face, the at least one slant being coupled to the flat and positioned at a slant angle, wherein the at least one slant includes a cutting edge.

The method of providing blowout preventer ram actuator which will move a blowout preventer shear ram into the bore of the blowout preventer and retract the blowout preventer shear ram from the bore of the blowout preventer, comprising providing a first and second piston, pressuring the second cylinder extension area to move the blowout preventer shear ram into contact with the pipe to be sheared while venting the second cylinder, sensing that the blowout preventer shear ram has contacted the pipe to be sheared, pressuring the first and the second cylinder to shear the pipe and pressuring the first cylinder to retract the shear ram.

A blowout preventer and method of operating a wellbore. The blowout preventer has a main body containing a wellbore, a passage transverse to the wellbore, a shearing device located in the passage; and a charge that, when activated, propels the shearing device along the passage and across the wellbore to close the wellbore and prevent a blowout.

A well pressure control device includes a housing having a through bore. A pressure chamber has a piston movably disposed therein. The pressure chamber is coupled at one end to the housing transversely to the through bore. The actuating piston defines a pressure source side and a through bore side of the pressure chamber. A fluid pressure source is coupled to the other end of the pressure chamber. A closure element is disposed in the pressure chamber on the through bore side. At least one locking element is coupled to the pressure chamber at an axial position along the pressure chamber on the through bore side.

A method includes initiating, by a computer system, a shear ram closure in a central bore of a blow-out preventer stack in response to a determination by the computer system of a loss of well control event and a determination by the computer system, based on a measurement received by the computer system from a joint locator sensor, that a tubing joint is not present within the central bore of the blow-out preventer stack. A pipe ram closure is initiated in response to a determination by the computer system that the shear ram has not fully closed after a predetermined time period since the initiation of the shear closure sequence.

A blowout preventer includes a main body having a through bore. A pressure chamber is located adjacent to and transverse to the through bore. A gate is disposed in the pressure chamber. An insert is disposed in the main body and defines an opening therethrough parallel to the through bore. The insert also defines a passage therethrough transverse to the through bore for passage of the gate.