BLOWOUT PREVENTER Russian patent published in 2003 - IPC

FIELD: equipment applicable in oil and gas servicing. SUBSTANCE: preventer has double-section body with axial channel. Each body section has two pipe-rams with drive and sealing rings. Pipe-rams serve for sealing of pipes run into well through body axial channel. Body lower section has pipe-rams with diameter of sealed hole differing from diameter of sealed hole of upper section. Lower section has plate and drive. Plate has supporting ring and movable plug. Drive is made for plate motion up to coincidence of plug symmetry axes and sealed hole. Due to pressure action from well side, subsequent raising of plate is provided to zone of sealing rings until force thrust against plate supporting ring and closing of sealed hole remaining between sealing rings of shifted pipe-rams with no pipes in well. In case of well seal failure, plug is forced downward with subsequent moving apart of pipe- rams with plate. EFFECT: provided double-section blowout preventer capable of sealing two different type-size of pipes and axial channel in body in absence of pipes in well without disassembly of sections and replacement of pipe-rams under field conditions. 6 dwg