The present invention provides a blowout preventer in which a first set of hydraulic ports communicate with either side of a first piston coupled to a first piston rod, a second set of hydraulic ports communicate with either side of a second piston coupled to a second piston rod, and the first and second pistons and associated piston rods may be actuated independent of each other. Each piston rod is coupled to a ram, and preferably, the first piston rod is coupled to a pipe ram and the second piston rod is coupled to a slip ram. A feature of the present invention provides that all of these elements are contained within a single chamber extending laterally of and communicating with the bore of a BOP.
A method and a device for replacing a seal element in an undersea blowout preventer is provided. A complete system includes a control center on the surface, an umbilical from the control center to a remotely operated vehicle (ROV), and a seal element carrier manipulated by the ROV. The carrier includes either retrieving tool or a running tool, which retains a cartridge which is to be inserted into or has been retrieved from a BOP. The cartridge is split along a vertical plane, with each half of the cartridge becoming a temporarily integral part of a pipe ram on either side of the BOP. Alignment ramps on the cartridge mate with complementary surfaces on the respective faces of the pipe rams.
A method and a device for replacing a seal element in an undersea blowout preventer is provided. A complete system includes a control center on the surface, an umbilical from the control center to a remotely operated vehicle (ROV), and a seal element carrier manipulated by the ROV. The carrier includes either retrieving tool or a running tool, which retains a cartridge which is to be inserted into or has been retrieved from a BOP. The cartridge is split along a vertical plane, with each half of the cartridge becoming a temporarily integral part of a pipe ram on either side of the BOP. Alignment ramps on the cartridge mate with complementary surfaces on the respective faces of the pipe rams.
A method and a device for replacing a seal element in an undersea blowout preventer is provided. A complete system includes a control center on the surface, an umbilical from the control center to a remotely operated vehicle (ROV), and a seal element carrier manipulated by the ROV. The carrier includes either a retrieving tool or a running tool, which retains a cartridge which is to be inserted into or has been retrieved from a BOP. The cartridge is split along a vertical plane, with each half of the cartridge becoming a temporarily integral part of a pipe ram on either side of the BOP. Alignment ramps on the cartridge mate with complementary surfaces on the respective faces of the pipe rams. The retrieving tool preferably includes means for hydraulically actuating the retrieving tool with pressure through the umbilical, such as coiled tubing.
A ram actuating mechanism 20 for a blowout preventer 10, the ram actuating mechanism 20 including a hydraulic booster for enhancing the ram closing force. The ram actuating mechanism 20 may be compatible for use with primary pistons 25 which include internal moving components, such as self locking pistons. The ram actuating mechanism 20 providing a hydraulic booster without increasing the diameter of the booster pistons above the diameter of the primary piston, such that BOP stack height need not be increased to accommodate a relatively large diameter hydraulic booster. The ram actuating mechanism 20 may utilize the same piston housing 60 as used by the primary piston, and the booster pistons 26, 28 may act mechanically in series upon the primary piston 25 to increase axial ram closing force. The ram actuating mechanism 20 may be capable of retro-fitting existing ram actuating mechanisms.
An improved shear/seal ram assembly used in ram-type BOPs is disclosed. The disclosed invention is a unique shear/seal ram assembly in which rail seal actuators attached to or integrally formed in a planar surface of one shear blade mate with and slide within corresponding rail guide grooves formed in a planar surface of a second shear blade. As the shear blades move over each other, the rail seal actuators slide within the rail guide grooves, eventually coming into contact with a seal actuator plate of a unique blade-to-blade seal assembly placed within a shear blade seal groove. Continued movement of the shear blades over each other causes the rail seal actuators to compress, or "energize," the blade-to-blade seal of the blade-to-blade seal assembly, thereby providing a pressure tight seal between the shear blade assemblies.
