DEVICE FOR WELLHEAD SEALING, UNIT OF SEALS AND UNIT OF STOP SLIPS Russian patent published in 1997 - IPC

FIELD: oil and gas production; applicable in overhauls and underground repairs of oil and gas wells in round trip operations of continuous pipe string and tubings. SUBSTANCE: device has units of pipe, stop and blind slips. There is also unit of seals, unit of pipe pinching, line of leak discharge and means for pipe piercing. Provision is made for operation of unit of seals in the mode of self-sealing. Units are made in form of module units and combined by quick-break connecting members into preventer assembly. There is removable base for connection to any module unit. EFFECT: higher reliability of wellhead sealing and extended field of application. 17 cl, 11 dwg